bevy/Cargo.toml

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2019-11-13 03:36:02 +00:00
[package]
name = "bevy"
version = "0.12.0"
edition = "2021"
categories = ["game-engines", "graphics", "gui", "rendering"]
2020-08-10 00:24:27 +00:00
description = "A refreshingly simple data-driven game engine and app framework"
exclude = ["assets/", "tools/", ".github/", "crates/", "examples/wasm/assets/"]
2020-08-10 00:24:27 +00:00
homepage = "https://bevyengine.org"
keywords = ["game", "engine", "gamedev", "graphics", "bevy"]
Relicense Bevy under the dual MIT or Apache-2.0 license (#2509) This relicenses Bevy under the dual MIT or Apache-2.0 license. For rationale, see #2373. * Changes the LICENSE file to describe the dual license. Moved the MIT license to docs/LICENSE-MIT. Added the Apache-2.0 license to docs/LICENSE-APACHE. I opted for this approach over dumping both license files at the root (the more common approach) for a number of reasons: * Github links to the "first" license file (LICENSE-APACHE) in its license links (you can see this in the wgpu and rust-analyzer repos). People clicking these links might erroneously think that the apache license is the only option. Rust and Amethyst both use COPYRIGHT or COPYING files to solve this problem, but this creates more file noise (if you do everything at the root) and the naming feels way less intuitive. * People have a reflex to look for a LICENSE file. By providing a single license file at the root, we make it easy for them to understand our licensing approach. * I like keeping the root clean and noise free * There is precedent for putting the apache and mit license text in sub folders (amethyst) * Removed the `Copyright (c) 2020 Carter Anderson` copyright notice from the MIT license. I don't care about this attribution, it might make license compliance more difficult in some cases, and it didn't properly attribute other contributors. We shoudn't replace it with something like "Copyright (c) 2021 Bevy Contributors" because "Bevy Contributors" is not a legal entity. Instead, we just won't include the copyright line (which has precedent ... Rust also uses this approach). * Updates crates to use the new "MIT OR Apache-2.0" license value * Removes the old legion-transform license file from bevy_transform. bevy_transform has been its own, fully custom implementation for a long time and that license no longer applies. * Added a License section to the main readme * Updated our Bevy Plugin licensing guidelines. As a follow-up we should update the website to properly describe the new license. Closes #2373
2021-07-23 21:11:51 +00:00
license = "MIT OR Apache-2.0"
readme = "README.md"
repository = "https://github.com/bevyengine/bevy"
rust-version = "1.70.0"
[workspace]
exclude = [
"benches",
"crates/bevy_ecs_compile_fail_tests",
bevy_derive: Add `#[deref]` attribute (#8552) # Objective Bevy code tends to make heavy use of the [newtype]( https://doc.rust-lang.org/rust-by-example/generics/new_types.html) pattern, which is why we have a dedicated derive for [`Deref`](https://doc.rust-lang.org/std/ops/trait.Deref.html) and [`DerefMut`](https://doc.rust-lang.org/std/ops/trait.DerefMut.html). This derive works for any struct with a single field: ```rust #[derive(Component, Deref, DerefMut)] struct MyNewtype(usize); ``` One reason for the single-field limitation is to prevent confusion and footguns related that would arise from allowing multi-field structs: <table align="center"> <tr> <th colspan="2"> Similar structs, different derefs </th> </tr> <tr> <td> ```rust #[derive(Deref, DerefMut)] struct MyStruct { foo: usize, // <- Derefs usize bar: String, } ``` </td> <td> ```rust #[derive(Deref, DerefMut)] struct MyStruct { bar: String, // <- Derefs String foo: usize, } ``` </td> </tr> <tr> <th colspan="2"> Why `.1`? </th> </tr> <tr> <td colspan="2"> ```rust #[derive(Deref, DerefMut)] struct MyStruct(Vec<usize>, Vec<f32>); let mut foo = MyStruct(vec![123], vec![1.23]); // Why can we skip the `.0` here? foo.push(456); // But not here? foo.1.push(4.56); ``` </td> </tr> </table> However, there are certainly cases where it's useful to allow for structs with multiple fields. Such as for structs with one "real" field and one `PhantomData` to allow for generics: ```rust #[derive(Deref, DerefMut)] struct MyStruct<T>( // We want use this field for the `Deref`/`DerefMut` impls String, // But we need this field so that we can make this struct generic PhantomData<T> ); // ERROR: Deref can only be derived for structs with a single field // ERROR: DerefMut can only be derived for structs with a single field ``` Additionally, the possible confusion and footguns are mainly an issue for newer Rust/Bevy users. Those familiar with `Deref` and `DerefMut` understand what adding the derive really means and can anticipate its behavior. ## Solution Allow users to opt into multi-field `Deref`/`DerefMut` derives using a `#[deref]` attribute: ```rust #[derive(Deref, DerefMut)] struct MyStruct<T>( // Use this field for the `Deref`/`DerefMut` impls #[deref] String, // We can freely include any other field without a compile error PhantomData<T> ); ``` This prevents the footgun pointed out in the first issue described in the previous section, but it still leaves the possible confusion surrounding `.0`-vs-`.#`. However, the idea is that by making this behavior explicit with an attribute, users will be more aware of it and can adapt appropriately. --- ## Changelog - Added `#[deref]` attribute to `Deref` and `DerefMut` derives
2023-05-16 18:29:09 +00:00
"crates/bevy_macros_compile_fail_tests",
"crates/bevy_reflect_compile_fail_tests",
]
members = [
"crates/*",
"examples/mobile",
"tools/ci",
"tools/build-templated-pages",
"tools/build-wasm-example",
"tools/example-showcase",
"errors",
]
2019-11-13 03:36:02 +00:00
2020-03-11 05:20:49 +00:00
[features]
default = [
"animation",
"bevy_asset",
"bevy_audio",
"bevy_gilrs",
"bevy_scene",
"bevy_winit",
"bevy_core_pipeline",
"bevy_pbr",
"bevy_gltf",
"bevy_render",
"bevy_sprite",
"bevy_text",
"bevy_ui",
"multi-threaded",
"png",
"hdr",
"vorbis",
"x11",
Immediate Mode Line/Gizmo Drawing (#6529) # Objective Add a convenient immediate mode drawing API for visual debugging. Fixes #5619 Alternative to #1625 Partial alternative to #5734 Based off https://github.com/Toqozz/bevy_debug_lines with some changes: * Simultaneous support for 2D and 3D. * Methods for basic shapes; circles, spheres, rectangles, boxes, etc. * 2D methods. * Removed durations. Seemed niche, and can be handled by users. <details> <summary>Performance</summary> Stress tested using Bevy's recommended optimization settings for the dev profile with the following command. ```bash cargo run --example many_debug_lines \ --config "profile.dev.package.\"*\".opt-level=3" \ --config "profile.dev.opt-level=1" ``` I dipped to 65-70 FPS at 300,000 lines CPU: 3700x RAM Speed: 3200 Mhz GPU: 2070 super - probably not very relevant, mostly cpu/memory bound </details> <details> <summary>Fancy bloom screenshot</summary> ![Screenshot_20230207_155033](https://user-images.githubusercontent.com/29694403/217291980-f1e0500e-7a14-4131-8c96-eaaaf52596ae.png) </details> ## Changelog * Added `GizmoPlugin` * Added `Gizmos` system parameter for drawing lines and wireshapes. ### TODO - [ ] Update changelog - [x] Update performance numbers - [x] Add credit to PR description ### Future work - Cache rendering primitives instead of constructing them out of line segments each frame. - Support for drawing solid meshes - Interactions. (See [bevy_mod_gizmos](https://github.com/LiamGallagher737/bevy_mod_gizmos)) - Fancier line drawing. (See [bevy_polyline](https://github.com/ForesightMiningSoftwareCorporation/bevy_polyline)) - Support for `RenderLayers` - Display gizmos for a certain duration. Currently everything displays for one frame (ie. immediate mode) - Changing settings per drawn item like drawing on top or drawing to different `RenderLayers` Co-Authored By: @lassade <felipe.jorge.pereira@gmail.com> Co-Authored By: @The5-1 <agaku@hotmail.de> Co-Authored By: @Toqozz <toqoz@hotmail.com> Co-Authored By: @nicopap <nico@nicopap.ch> --------- Co-authored-by: Robert Swain <robert.swain@gmail.com> Co-authored-by: IceSentry <c.giguere42@gmail.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2023-03-20 20:57:54 +00:00
"bevy_gizmos",
"android_shared_stdcxx",
Revamp Bloom (#6677) ![image](https://user-images.githubusercontent.com/47158642/220197588-25e11022-02e4-45f3-b2e5-392c4ce7a025.png) Huge credit to @StarLederer, who did almost all of the work on this. We're just reusing this PR to keep everything in one place. # Objective 1. Make bloom more physically based. 1. Improve artistic control. 1. Allow to use bloom as screen blur. 1. Fix #6634. 1. Address #6655 (although the author makes incorrect conclusions). ## Solution 1. Set the default threshold to 0. 2. Lerp between bloom textures when `composite_mode: BloomCompositeMode::EnergyConserving`. 1. Use [a parametric function](https://starlederer.github.io/bloom) to control blend levels for each bloom texture. In the future this can be controlled per-pixel for things like lens dirt. 3. Implement BloomCompositeMode::Additive` for situations where the old school look is desired. ## Changelog * Bloom now looks different. * Added `BloomSettings:lf_boost`, `BloomSettings:lf_boost_curvature`, `BloomSettings::high_pass_frequency` and `BloomSettings::composite_mode`. * `BloomSettings::scale` removed. * `BloomSettings::knee` renamed to `BloomPrefilterSettings::softness`. * `BloomSettings::threshold` renamed to `BloomPrefilterSettings::threshold`. * The bloom example has been renamed to bloom_3d and improved. A bloom_2d example was added. ## Migration Guide * Refactor mentions of `BloomSettings::knee` and `BloomSettings::threshold` as `BloomSettings::prefilter_settings` where knee is now `softness`. * If defined without `..default()` add `..default()` to definitions of `BloomSettings` instances or manually define missing fields. * Adapt to Bloom looking visually different (if needed). Co-authored-by: Herman Lederer <germans.lederers@gmail.com>
2023-03-04 12:05:26 +00:00
"tonemapping_luts",
"default_font",
Webgpu support (#8336) # Objective - Support WebGPU - alternative to #5027 that doesn't need any async / await - fixes #8315 - Surprise fix #7318 ## Solution ### For async renderer initialisation - Update the plugin lifecycle: - app builds the plugin - calls `plugin.build` - registers the plugin - app starts the event loop - event loop waits for `ready` of all registered plugins in the same order - returns `true` by default - then call all `finish` then all `cleanup` in the same order as registered - then execute the schedule In the case of the renderer, to avoid anything async: - building the renderer plugin creates a detached task that will send back the initialised renderer through a mutex in a resource - `ready` will wait for the renderer to be present in the resource - `finish` will take that renderer and place it in the expected resources by other plugins - other plugins (that expect the renderer to be available) `finish` are called and they are able to set up their pipelines - `cleanup` is called, only custom one is still for pipeline rendering ### For WebGPU support - update the `build-wasm-example` script to support passing `--api webgpu` that will build the example with WebGPU support - feature for webgl2 was always enabled when building for wasm. it's now in the default feature list and enabled on all platforms, so check for this feature must also check that the target_arch is `wasm32` --- ## Migration Guide - `Plugin::setup` has been renamed `Plugin::cleanup` - `Plugin::finish` has been added, and plugins adding pipelines should do it in this function instead of `Plugin::build` ```rust // Before impl Plugin for MyPlugin { fn build(&self, app: &mut App) { app.insert_resource::<MyResource> .add_systems(Update, my_system); let render_app = match app.get_sub_app_mut(RenderApp) { Ok(render_app) => render_app, Err(_) => return, }; render_app .init_resource::<RenderResourceNeedingDevice>() .init_resource::<OtherRenderResource>(); } } // After impl Plugin for MyPlugin { fn build(&self, app: &mut App) { app.insert_resource::<MyResource> .add_systems(Update, my_system); let render_app = match app.get_sub_app_mut(RenderApp) { Ok(render_app) => render_app, Err(_) => return, }; render_app .init_resource::<OtherRenderResource>(); } fn finish(&self, app: &mut App) { let render_app = match app.get_sub_app_mut(RenderApp) { Ok(render_app) => render_app, Err(_) => return, }; render_app .init_resource::<RenderResourceNeedingDevice>(); } } ```
2023-05-04 22:07:57 +00:00
"webgl2",
]
# Force dynamic linking, which improves iterative compile times
Remove the bevy_dylib feature (#9516) # Objective There is a `bevy_dylib` feature that cargo automatically creates due to the bevy_dylib crate being optional. This can be a footgun as I think we want users to always use the `dynamic_linking` feature for this. For example `bevy_dylib` was used in [ridiculous_bevy_hot_reloading:lib.rs#L93](https://github.com/DGriffin91/ridiculous_bevy_hot_reloading/blob/400099bcc10f4ef974af491f55e8acefe273e4bc/src/lib.rs#L93) and since I was using dynamic_linking it ended up hot reloading with a slightly different configured library causing hot reloading to fail. ## Solution Use "dep:" syntax in the `dynamic_linking` feature to prevent bevy_dylib automatically becoming a cargo feature. This is documented here: https://doc.rust-lang.org/cargo/reference/features.html#optional-dependencies It will now raise this error when you try to compile with the bevy_dylib feature: > error: Package `bevy v0.12.0-dev (C:\Users\Paul\Projects\Rust\bevy)` does not have feature `bevy_dylib`. It has an optional dependency with that name, but that dependency uses the "dep:" syntax in the features table, so it does not have an implicit feature with that name. --- ## Changelog `bevy_dylib` is no longer a feature ## Migration Guide If you were using Bevy's `bevy_dylib` feature, use Bevy's `dynamic_linking` feature instead. ```shell # 0.11 cargo run --features bevy/bevy_dylib # 0.12 cargo run --features bevy/dynamic_linking ``` ```toml [dependencies] # 0.11 bevy = { version = "0.11", features = ["bevy_dylib"] } # 0.12 bevy = { version = "0.12", features = ["dynamic_linking"] } ```
2023-08-21 01:38:00 +00:00
dynamic_linking = ["dep:bevy_dylib", "bevy_internal/dynamic_linking"]
# Provides animation functionality
bevy_animation = ["bevy_internal/bevy_animation"]
# Provides asset functionality
bevy_asset = ["bevy_internal/bevy_asset"]
# Provides audio functionality
bevy_audio = ["bevy_internal/bevy_audio"]
# Provides cameras and other basic render pipeline features
bevy_core_pipeline = [
"bevy_internal/bevy_core_pipeline",
"bevy_asset",
"bevy_render",
]
# Plugin for dynamic loading (using [libloading](https://crates.io/crates/libloading))
bevy_dynamic_plugin = ["bevy_internal/bevy_dynamic_plugin"]
# Adds gamepad support
bevy_gilrs = ["bevy_internal/bevy_gilrs"]
# [glTF](https://www.khronos.org/gltf/) support
bevy_gltf = ["bevy_internal/bevy_gltf", "bevy_asset", "bevy_scene", "bevy_pbr"]
# Adds PBR rendering
bevy_pbr = [
"bevy_internal/bevy_pbr",
"bevy_asset",
"bevy_render",
"bevy_core_pipeline",
]
# Provides rendering functionality
bevy_render = ["bevy_internal/bevy_render"]
# Provides scene functionality
bevy_scene = ["bevy_internal/bevy_scene", "bevy_asset"]
# Provides sprite functionality
bevy_sprite = ["bevy_internal/bevy_sprite", "bevy_render", "bevy_core_pipeline"]
# Provides text functionality
bevy_text = ["bevy_internal/bevy_text", "bevy_asset", "bevy_sprite"]
# A custom ECS-driven UI framework
bevy_ui = [
"bevy_internal/bevy_ui",
"bevy_core_pipeline",
"bevy_text",
"bevy_sprite",
]
# winit window and input backend
bevy_winit = ["bevy_internal/bevy_winit"]
Immediate Mode Line/Gizmo Drawing (#6529) # Objective Add a convenient immediate mode drawing API for visual debugging. Fixes #5619 Alternative to #1625 Partial alternative to #5734 Based off https://github.com/Toqozz/bevy_debug_lines with some changes: * Simultaneous support for 2D and 3D. * Methods for basic shapes; circles, spheres, rectangles, boxes, etc. * 2D methods. * Removed durations. Seemed niche, and can be handled by users. <details> <summary>Performance</summary> Stress tested using Bevy's recommended optimization settings for the dev profile with the following command. ```bash cargo run --example many_debug_lines \ --config "profile.dev.package.\"*\".opt-level=3" \ --config "profile.dev.opt-level=1" ``` I dipped to 65-70 FPS at 300,000 lines CPU: 3700x RAM Speed: 3200 Mhz GPU: 2070 super - probably not very relevant, mostly cpu/memory bound </details> <details> <summary>Fancy bloom screenshot</summary> ![Screenshot_20230207_155033](https://user-images.githubusercontent.com/29694403/217291980-f1e0500e-7a14-4131-8c96-eaaaf52596ae.png) </details> ## Changelog * Added `GizmoPlugin` * Added `Gizmos` system parameter for drawing lines and wireshapes. ### TODO - [ ] Update changelog - [x] Update performance numbers - [x] Add credit to PR description ### Future work - Cache rendering primitives instead of constructing them out of line segments each frame. - Support for drawing solid meshes - Interactions. (See [bevy_mod_gizmos](https://github.com/LiamGallagher737/bevy_mod_gizmos)) - Fancier line drawing. (See [bevy_polyline](https://github.com/ForesightMiningSoftwareCorporation/bevy_polyline)) - Support for `RenderLayers` - Display gizmos for a certain duration. Currently everything displays for one frame (ie. immediate mode) - Changing settings per drawn item like drawing on top or drawing to different `RenderLayers` Co-Authored By: @lassade <felipe.jorge.pereira@gmail.com> Co-Authored By: @The5-1 <agaku@hotmail.de> Co-Authored By: @Toqozz <toqoz@hotmail.com> Co-Authored By: @nicopap <nico@nicopap.ch> --------- Co-authored-by: Robert Swain <robert.swain@gmail.com> Co-authored-by: IceSentry <c.giguere42@gmail.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2023-03-20 20:57:54 +00:00
# Adds support for rendering gizmos
bevy_gizmos = ["bevy_internal/bevy_gizmos"]
# Tracing support, saving a file in Chrome Tracing format
trace_chrome = ["trace", "bevy_internal/trace_chrome"]
# Tracing support, exposing a port for Tracy
trace_tracy = ["trace", "bevy_internal/trace_tracy"]
# Tracing support, with memory profiling, exposing a port for Tracy
trace_tracy_memory = [
"trace",
"bevy_internal/trace_tracy",
"bevy_internal/trace_tracy_memory",
]
# Tracing support
trace = ["bevy_internal/trace"]
# Save a trace of all wgpu calls
wgpu_trace = ["bevy_internal/wgpu_trace"]
# EXR image format support
exr = ["bevy_internal/exr"]
# HDR image format support
hdr = ["bevy_internal/hdr"]
# PNG image format support
png = ["bevy_internal/png"]
# TGA image format support
tga = ["bevy_internal/tga"]
# JPEG image format support
jpeg = ["bevy_internal/jpeg"]
# BMP image format support
bmp = ["bevy_internal/bmp"]
Added `WebP` image format support (#8220) # Objective WebP is a modern image format developed by Google that offers a significant reduction in file size compared to other image formats such as PNG and JPEG, while still maintaining good image quality. This makes it particularly useful for games with large numbers of images, such as those with high-quality textures or detailed sprites, where file size and loading times can have a significant impact on performance. By adding support for WebP images in Bevy, game developers using this engine can now take advantage of this modern image format and reduce the memory usage and loading times of their games. This improvement can ultimately result in a better gaming experience for players. In summary, the objective of adding WebP image format support in Bevy is to enable game developers to use a modern image format that provides better compression rates and smaller file sizes, resulting in faster loading times and reduced memory usage for their games. ## Solution To add support for WebP images in Bevy, this pull request leverages the existing `image` crate support for WebP. This implementation is easily integrated into the existing Bevy asset-loading system. To maintain compatibility with existing Bevy projects, WebP image support is disabled by default, and developers can enable it by adding a feature flag to their project's `Cargo.toml` file. With this feature, Bevy becomes even more versatile for game developers and provides a valuable addition to the game engine. --- ## Changelog - Added support for WebP image format in Bevy game engine ## Migration Guide To enable WebP image support in your Bevy project, add the following line to your project's Cargo.toml file: ```toml bevy = { version = "*", features = ["webp"]} ```
2023-03-28 19:53:55 +00:00
# WebP image format support
webp = ["bevy_internal/webp"]
# Basis Universal compressed texture support
basis-universal = ["bevy_internal/basis-universal"]
# DDS compressed texture support
dds = ["bevy_internal/dds"]
# KTX2 compressed texture support
ktx2 = ["bevy_internal/ktx2"]
# PNM image format support, includes pam, pbm, pgm and ppm
pnm = ["bevy_internal/pnm"]
# For KTX2 supercompression
zlib = ["bevy_internal/zlib"]
# For KTX2 supercompression
zstd = ["bevy_internal/zstd"]
# FLAC audio format support
flac = ["bevy_internal/flac"]
# MP3 audio format support
mp3 = ["bevy_internal/mp3"]
# OGG/VORBIS audio format support
vorbis = ["bevy_internal/vorbis"]
# WAV audio format support
wav = ["bevy_internal/wav"]
# MP3 audio format support (through minimp3)
minimp3 = ["bevy_internal/minimp3"]
# AAC audio format support (through symphonia)
symphonia-aac = ["bevy_internal/symphonia-aac"]
# AAC, FLAC, MP3, MP4, OGG/VORBIS, and WAV audio formats support (through symphonia)
symphonia-all = ["bevy_internal/symphonia-all"]
# FLAC audio format support (through symphonia)
symphonia-flac = ["bevy_internal/symphonia-flac"]
# MP4 audio format support (through symphonia)
symphonia-isomp4 = ["bevy_internal/symphonia-isomp4"]
# OGG/VORBIS audio format support (through symphonia)
symphonia-vorbis = ["bevy_internal/symphonia-vorbis"]
# WAV audio format support (through symphonia)
symphonia-wav = ["bevy_internal/symphonia-wav"]
# Enable serialization support through serde
serialize = ["bevy_internal/serialize"]
# Enables multithreaded parallelism in the engine. Disabling it forces all engine tasks to run on a single thread.
multi-threaded = ["bevy_internal/multi-threaded"]
# Use async-io's implementation of block_on instead of futures-lite's implementation. This is preferred if your application uses async-io.
async-io = ["bevy_internal/async-io"]
# Wayland display server support
wayland = ["bevy_internal/wayland"]
# X11 display server support
x11 = ["bevy_internal/x11"]
2020-05-06 01:44:32 +00:00
# Enable rendering of font glyphs using subpixel accuracy
subpixel_glyph_atlas = ["bevy_internal/subpixel_glyph_atlas"]
# Enable systems that allow for automated testing on CI
bevy_ci_testing = ["bevy_internal/bevy_ci_testing"]
# Enable animation support, and glTF animation loading
animation = ["bevy_internal/animation", "bevy_animation"]
# Enable using a shared stdlib for cxx on Android
android_shared_stdcxx = ["bevy_internal/android_shared_stdcxx"]
# Enable detailed trace event logging. These trace events are expensive even when off, thus they require compile time opt-in
Introduce detailed_trace macro, use in TrackedRenderPass (#7639) Profiles show that in extremely hot loops, like the draw loops in the renderer, invoking the trace! macro has noticeable overhead, even if the trace log level is not enabled. Solve this by introduce a 'wrapper' detailed_trace macro around trace, that wraps the trace! log statement in a trivially false if statement unless a cargo feature is enabled # Objective - Eliminate significant overhead observed with trace-level logging in render hot loops, even when trace log level is not enabled. - This is an alternative solution to the one proposed in #7223 ## Solution - Introduce a wrapper around the `trace!` macro called `detailed_trace!`. This macro wraps the `trace!` macro with an if statement that is conditional on a new cargo feature, `detailed_trace`. When the feature is not enabled (the default), then the if statement is trivially false and should be optimized away at compile time. - Convert the observed hot occurrences of trace logging in `TrackedRenderPass` with this new macro. Testing the results of ``` cargo run --profile stress-test --features bevy/trace_tracy --example many_cubes -- spheres ``` ![image](https://user-images.githubusercontent.com/1222141/218298552-38551717-b062-4c64-afdc-a60267ac984d.png) shows significant improvement of the `main_opaque_pass_3d` of the renderer, a median time decrease from 6.0ms to 3.5ms. --- ## Changelog - For performance reasons, some detailed renderer trace logs now require the use of cargo feature `detailed_trace` in addition to setting the log level to `TRACE` in order to be shown. ## Migration Guide - Some detailed bevy trace events now require the use of the cargo feature `detailed_trace` in addition to enabling `TRACE` level logging to view. Should you wish to see these logs, please compile your code with the bevy feature `detailed_trace`. Currently, the only logs that are affected are the renderer logs pertaining to `TrackedRenderPass` functions
2023-02-13 18:20:27 +00:00
detailed_trace = ["bevy_internal/detailed_trace"]
Log a warning when the `tonemapping_luts` feature is disabled but required for the selected tonemapper. (#10253) # Objective Make it obvious why stuff renders pink when rendering stuff with bevy with `default_features = false` and bevy's default tonemapper (TonyMcMapFace, it requires a LUT which requires the `tonemapping_luts`, `ktx2`, and `zstd` features). Not sure if this should be considered as fixing these issues, but in my previous PR (https://github.com/bevyengine/bevy/pull/9073, and old discussions on discord that I only somewhat remember) it seemed like we didn't want to make ktx2 and zstd required features for bevy_core_pipeline. Related https://github.com/bevyengine/bevy/issues/9179 Related https://github.com/bevyengine/bevy/issues/9098 ## Solution This logs an error when a LUT based tonemapper is used without the `tonemapping_luts` feature enabled, and cleans up the default features a bit (`tonemapping_luts` now includes the `ktx2` and `zstd` features, since it panics without them). Another solution would be to fall back to a non-lut based tonemapper, but I don't like this solution as then it's not explicitly clear to users why eg. a library example renders differently than a normal bevy app (if the library forgot the `tonemapping_luts` feature). I did remove the `ktx2` and `zstd` features from the list of default features in Cargo.toml, as I don't believe anything else currently in bevy relies on them (or at least searching through every hit for `ktx2` and `zstd` didn't show anything except loading an environment map in some examples), and they still show up in the `cargo_features` doc as default features. --- ## Changelog - The `tonemapping_luts` feature now includes both the `ktx2` and `zstd` features to avoid a panic when the `tonemapping_luts` feature was enable without both the `ktx2` and `zstd` feature enabled.
2023-10-27 02:07:24 +00:00
# Include tonemapping Look Up Tables KTX2 files. If everything is pink, you need to enable this feature or change the `Tonemapping` method on your `Camera2dBundle` or `Camera3dBundle`.
tonemapping_luts = ["bevy_internal/tonemapping_luts", "ktx2", "zstd"]
# Enable AccessKit on Unix backends (currently only works with experimental screen readers and forks.)
accesskit_unix = ["bevy_internal/accesskit_unix"]
# Enable assertions to check the validity of parameters passed to glam
glam_assert = ["bevy_internal/glam_assert"]
# Enable assertions in debug builds to check the validity of parameters passed to glam
debug_glam_assert = ["bevy_internal/debug_glam_assert"]
# Include a default font, containing only ASCII characters, at the cost of a 20kB binary size increase
default_font = ["bevy_internal/default_font"]
# Enable support for shaders in GLSL
shader_format_glsl = ["bevy_internal/shader_format_glsl"]
# Enable support for shaders in SPIR-V
shader_format_spirv = ["bevy_internal/shader_format_spirv"]
`StandardMaterial` Light Transmission (#8015) # Objective <img width="1920" alt="Screenshot 2023-04-26 at 01 07 34" src="https://user-images.githubusercontent.com/418473/234467578-0f34187b-5863-4ea1-88e9-7a6bb8ce8da3.png"> This PR adds both diffuse and specular light transmission capabilities to the `StandardMaterial`, with support for screen space refractions. This enables realistically representing a wide range of real-world materials, such as: - Glass; (Including frosted glass) - Transparent and translucent plastics; - Various liquids and gels; - Gemstones; - Marble; - Wax; - Paper; - Leaves; - Porcelain. Unlike existing support for transparency, light transmission does not rely on fixed function alpha blending, and therefore works with both `AlphaMode::Opaque` and `AlphaMode::Mask` materials. ## Solution - Introduces a number of transmission related fields in the `StandardMaterial`; - For specular transmission: - Adds logic to take a view main texture snapshot after the opaque phase; (in order to perform screen space refractions) - Introduces a new `Transmissive3d` phase to the renderer, to which all meshes with `transmission > 0.0` materials are sent. - Calculates a light exit point (of the approximate mesh volume) using `ior` and `thickness` properties - Samples the snapshot texture with an adaptive number of taps across a `roughness`-controlled radius enabling “blurry” refractions - For diffuse transmission: - Approximates transmitted diffuse light by using a second, flipped + displaced, diffuse-only Lambertian lobe for each light source. ## To Do - [x] Figure out where `fresnel_mix()` is taking place, if at all, and where `dielectric_specular` is being calculated, if at all, and update them to use the `ior` value (Not a blocker, just a nice-to-have for more correct BSDF) - To the _best of my knowledge, this is now taking place, after 964340cdd. The fresnel mix is actually "split" into two parts in our implementation, one `(1 - fresnel(...))` in the transmission, and `fresnel()` in the light implementations. A surface with more reflectance now will produce slightly dimmer transmission towards the grazing angle, as more of the light gets reflected. - [x] Add `transmission_texture` - [x] Add `diffuse_transmission_texture` - [x] Add `thickness_texture` - [x] Add `attenuation_distance` and `attenuation_color` - [x] Connect values to glTF loader - [x] `transmission` and `transmission_texture` - [x] `thickness` and `thickness_texture` - [x] `ior` - [ ] `diffuse_transmission` and `diffuse_transmission_texture` (needs upstream support in `gltf` crate, not a blocker) - [x] Add support for multiple screen space refraction “steps” - [x] Conditionally create no transmission snapshot texture at all if `steps == 0` - [x] Conditionally enable/disable screen space refraction transmission snapshots - [x] Read from depth pre-pass to prevent refracting pixels in front of the light exit point - [x] Use `interleaved_gradient_noise()` function for sampling blur in a way that benefits from TAA - [x] Drill down a TAA `#define`, tweak some aspects of the effect conditionally based on it - [x] Remove const array that's crashing under HLSL (unless a new `naga` release with https://github.com/gfx-rs/naga/pull/2496 comes out before we merge this) - [ ] Look into alternatives to the `switch` hack for dynamically indexing the const array (might not be needed, compilers seem to be decent at expanding it) - [ ] Add pipeline keys for gating transmission (do we really want/need this?) - [x] Tweak some material field/function names? ## A Note on Texture Packing _This was originally added as a comment to the `specular_transmission_texture`, `thickness_texture` and `diffuse_transmission_texture` documentation, I removed it since it was more confusing than helpful, and will likely be made redundant/will need to be updated once we have a better infrastructure for preprocessing assets_ Due to how channels are mapped, you can more efficiently use a single shared texture image for configuring the following: - R - `specular_transmission_texture` - G - `thickness_texture` - B - _unused_ - A - `diffuse_transmission_texture` The `KHR_materials_diffuse_transmission` glTF extension also defines a `diffuseTransmissionColorTexture`, that _we don't currently support_. One might choose to pack the intensity and color textures together, using RGB for the color and A for the intensity, in which case this packing advice doesn't really apply. --- ## Changelog - Added a new `Transmissive3d` render phase for rendering specular transmissive materials with screen space refractions - Added rendering support for transmitted environment map light on the `StandardMaterial` as a fallback for screen space refractions - Added `diffuse_transmission`, `specular_transmission`, `thickness`, `ior`, `attenuation_distance` and `attenuation_color` to the `StandardMaterial` - Added `diffuse_transmission_texture`, `specular_transmission_texture`, `thickness_texture` to the `StandardMaterial`, gated behind a new `pbr_transmission_textures` cargo feature (off by default, for maximum hardware compatibility) - Added `Camera3d::screen_space_specular_transmission_steps` for controlling the number of “layers of transparency” rendered for transmissive objects - Added a `TransmittedShadowReceiver` component for enabling shadows in (diffusely) transmitted light. (disabled by default, as it requires carefully setting up the `thickness` to avoid self-shadow artifacts) - Added support for the `KHR_materials_transmission`, `KHR_materials_ior` and `KHR_materials_volume` glTF extensions - Renamed items related to temporal jitter for greater consistency ## Migration Guide - `SsaoPipelineKey::temporal_noise` has been renamed to `SsaoPipelineKey::temporal_jitter` - The `TAA` shader def (controlled by the presence of the `TemporalAntiAliasSettings` component in the camera) has been replaced with the `TEMPORAL_JITTER` shader def (controlled by the presence of the `TemporalJitter` component in the camera) - `MeshPipelineKey::TAA` has been replaced by `MeshPipelineKey::TEMPORAL_JITTER` - The `TEMPORAL_NOISE` shader def has been consolidated with `TEMPORAL_JITTER`
2023-10-31 20:59:02 +00:00
# Enable support for transmission-related textures in the `StandardMaterial`, at the risk of blowing past the global, per-shader texture limit on older/lower-end GPUs
pbr_transmission_textures = ["bevy_internal/pbr_transmission_textures"]
# Enable some limitations to be able to use WebGL2. If not enabled, it will default to WebGPU in Wasm. Please refer to the [WebGL2 and WebGPU](https://github.com/bevyengine/bevy/tree/latest/examples#webgl2-and-webgpu) section of the examples README for more information on how to run Wasm builds with WebGPU.
Webgpu support (#8336) # Objective - Support WebGPU - alternative to #5027 that doesn't need any async / await - fixes #8315 - Surprise fix #7318 ## Solution ### For async renderer initialisation - Update the plugin lifecycle: - app builds the plugin - calls `plugin.build` - registers the plugin - app starts the event loop - event loop waits for `ready` of all registered plugins in the same order - returns `true` by default - then call all `finish` then all `cleanup` in the same order as registered - then execute the schedule In the case of the renderer, to avoid anything async: - building the renderer plugin creates a detached task that will send back the initialised renderer through a mutex in a resource - `ready` will wait for the renderer to be present in the resource - `finish` will take that renderer and place it in the expected resources by other plugins - other plugins (that expect the renderer to be available) `finish` are called and they are able to set up their pipelines - `cleanup` is called, only custom one is still for pipeline rendering ### For WebGPU support - update the `build-wasm-example` script to support passing `--api webgpu` that will build the example with WebGPU support - feature for webgl2 was always enabled when building for wasm. it's now in the default feature list and enabled on all platforms, so check for this feature must also check that the target_arch is `wasm32` --- ## Migration Guide - `Plugin::setup` has been renamed `Plugin::cleanup` - `Plugin::finish` has been added, and plugins adding pipelines should do it in this function instead of `Plugin::build` ```rust // Before impl Plugin for MyPlugin { fn build(&self, app: &mut App) { app.insert_resource::<MyResource> .add_systems(Update, my_system); let render_app = match app.get_sub_app_mut(RenderApp) { Ok(render_app) => render_app, Err(_) => return, }; render_app .init_resource::<RenderResourceNeedingDevice>() .init_resource::<OtherRenderResource>(); } } // After impl Plugin for MyPlugin { fn build(&self, app: &mut App) { app.insert_resource::<MyResource> .add_systems(Update, my_system); let render_app = match app.get_sub_app_mut(RenderApp) { Ok(render_app) => render_app, Err(_) => return, }; render_app .init_resource::<OtherRenderResource>(); } fn finish(&self, app: &mut App) { let render_app = match app.get_sub_app_mut(RenderApp) { Ok(render_app) => render_app, Err(_) => return, }; render_app .init_resource::<RenderResourceNeedingDevice>(); } } ```
2023-05-04 22:07:57 +00:00
webgl2 = ["bevy_internal/webgl"]
# Enables the built-in asset processor for processed assets.
asset_processor = ["bevy_internal/asset_processor"]
Bevy Asset V2 (#8624) # Bevy Asset V2 Proposal ## Why Does Bevy Need A New Asset System? Asset pipelines are a central part of the gamedev process. Bevy's current asset system is missing a number of features that make it non-viable for many classes of gamedev. After plenty of discussions and [a long community feedback period](https://github.com/bevyengine/bevy/discussions/3972), we've identified a number missing features: * **Asset Preprocessing**: it should be possible to "preprocess" / "compile" / "crunch" assets at "development time" rather than when the game starts up. This enables offloading expensive work from deployed apps, faster asset loading, less runtime memory usage, etc. * **Per-Asset Loader Settings**: Individual assets cannot define their own loaders that override the defaults. Additionally, they cannot provide per-asset settings to their loaders. This is a huge limitation, as many asset types don't provide all information necessary for Bevy _inside_ the asset. For example, a raw PNG image says nothing about how it should be sampled (ex: linear vs nearest). * **Asset `.meta` files**: assets should have configuration files stored adjacent to the asset in question, which allows the user to configure asset-type-specific settings. These settings should be accessible during the pre-processing phase. Modifying a `.meta` file should trigger a re-processing / re-load of the asset. It should be possible to configure asset loaders from the meta file. * **Processed Asset Hot Reloading**: Changes to processed assets (or their dependencies) should result in re-processing them and re-loading the results in live Bevy Apps. * **Asset Dependency Tracking**: The current bevy_asset has no good way to wait for asset dependencies to load. It punts this as an exercise for consumers of the loader apis, which is unreasonable and error prone. There should be easy, ergonomic ways to wait for assets to load and block some logic on an asset's entire dependency tree loading. * **Runtime Asset Loading**: it should be (optionally) possible to load arbitrary assets dynamically at runtime. This necessitates being able to deploy and run the asset server alongside Bevy Apps on _all platforms_. For example, we should be able to invoke the shader compiler at runtime, stream scenes from sources like the internet, etc. To keep deployed binaries (and startup times) small, the runtime asset server configuration should be configurable with different settings compared to the "pre processor asset server". * **Multiple Backends**: It should be possible to load assets from arbitrary sources (filesystems, the internet, remote asset serves, etc). * **Asset Packing**: It should be possible to deploy assets in compressed "packs", which makes it easier and more efficient to distribute assets with Bevy Apps. * **Asset Handoff**: It should be possible to hold a "live" asset handle, which correlates to runtime data, without actually holding the asset in memory. Ex: it must be possible to hold a reference to a GPU mesh generated from a "mesh asset" without keeping the mesh data in CPU memory * **Per-Platform Processed Assets**: Different platforms and app distributions have different capabilities and requirements. Some platforms need lower asset resolutions or different asset formats to operate within the hardware constraints of the platform. It should be possible to define per-platform asset processing profiles. And it should be possible to deploy only the assets required for a given platform. These features have architectural implications that are significant enough to require a full rewrite. The current Bevy Asset implementation got us this far, but it can take us no farther. This PR defines a brand new asset system that implements most of these features, while laying the foundations for the remaining features to be built. ## Bevy Asset V2 Here is a quick overview of the features introduced in this PR. * **Asset Preprocessing**: Preprocess assets at development time into more efficient (and configurable) representations * **Dependency Aware**: Dependencies required to process an asset are tracked. If an asset's processed dependency changes, it will be reprocessed * **Hot Reprocessing/Reloading**: detect changes to asset source files, reprocess them if they have changed, and then hot-reload them in Bevy Apps. * **Only Process Changes**: Assets are only re-processed when their source file (or meta file) has changed. This uses hashing and timestamps to avoid processing assets that haven't changed. * **Transactional and Reliable**: Uses write-ahead logging (a technique commonly used by databases) to recover from crashes / forced-exits. Whenever possible it avoids full-reprocessing / only uncompleted transactions will be reprocessed. When the processor is running in parallel with a Bevy App, processor asset writes block Bevy App asset reads. Reading metadata + asset bytes is guaranteed to be transactional / correctly paired. * **Portable / Run anywhere / Database-free**: The processor does not rely on an in-memory database (although it uses some database techniques for reliability). This is important because pretty much all in-memory databases have unsupported platforms or build complications. * **Configure Processor Defaults Per File Type**: You can say "use this processor for all files of this type". * **Custom Processors**: The `Processor` trait is flexible and unopinionated. It can be implemented by downstream plugins. * **LoadAndSave Processors**: Most asset processing scenarios can be expressed as "run AssetLoader A, save the results using AssetSaver X, and then load the result using AssetLoader B". For example, load this png image using `PngImageLoader`, which produces an `Image` asset and then save it using `CompressedImageSaver` (which also produces an `Image` asset, but in a compressed format), which takes an `Image` asset as input. This means if you have an `AssetLoader` for an asset, you are already half way there! It also means that you can share AssetSavers across multiple loaders. Because `CompressedImageSaver` accepts Bevy's generic Image asset as input, it means you can also use it with some future `JpegImageLoader`. * **Loader and Saver Settings**: Asset Loaders and Savers can now define their own settings types, which are passed in as input when an asset is loaded / saved. Each asset can define its own settings. * **Asset `.meta` files**: configure asset loaders, their settings, enable/disable processing, and configure processor settings * **Runtime Asset Dependency Tracking** Runtime asset dependencies (ex: if an asset contains a `Handle<Image>`) are tracked by the asset server. An event is emitted when an asset and all of its dependencies have been loaded * **Unprocessed Asset Loading**: Assets do not require preprocessing. They can be loaded directly. A processed asset is just a "normal" asset with some extra metadata. Asset Loaders don't need to know or care about whether or not an asset was processed. * **Async Asset IO**: Asset readers/writers use async non-blocking interfaces. Note that because Rust doesn't yet support async traits, there is a bit of manual Boxing / Future boilerplate. This will hopefully be removed in the near future when Rust gets async traits. * **Pluggable Asset Readers and Writers**: Arbitrary asset source readers/writers are supported, both by the processor and the asset server. * **Better Asset Handles** * **Single Arc Tree**: Asset Handles now use a single arc tree that represents the lifetime of the asset. This makes their implementation simpler, more efficient, and allows us to cheaply attach metadata to handles. Ex: the AssetPath of a handle is now directly accessible on the handle itself! * **Const Typed Handles**: typed handles can be constructed in a const context. No more weird "const untyped converted to typed at runtime" patterns! * **Handles and Ids are Smaller / Faster To Hash / Compare**: Typed `Handle<T>` is now much smaller in memory and `AssetId<T>` is even smaller. * **Weak Handle Usage Reduction**: In general Handles are now considered to be "strong". Bevy features that previously used "weak `Handle<T>`" have been ported to `AssetId<T>`, which makes it statically clear that the features do not hold strong handles (while retaining strong type information). Currently Handle::Weak still exists, but it is very possible that we can remove that entirely. * **Efficient / Dense Asset Ids**: Assets now have efficient dense runtime asset ids, which means we can avoid expensive hash lookups. Assets are stored in Vecs instead of HashMaps. There are now typed and untyped ids, which means we no longer need to store dynamic type information in the ID for typed handles. "AssetPathId" (which was a nightmare from a performance and correctness standpoint) has been entirely removed in favor of dense ids (which are retrieved for a path on load) * **Direct Asset Loading, with Dependency Tracking**: Assets that are defined at runtime can still have their dependencies tracked by the Asset Server (ex: if you create a material at runtime, you can still wait for its textures to load). This is accomplished via the (currently optional) "asset dependency visitor" trait. This system can also be used to define a set of assets to load, then wait for those assets to load. * **Async folder loading**: Folder loading also uses this system and immediately returns a handle to the LoadedFolder asset, which means folder loading no longer blocks on directory traversals. * **Improved Loader Interface**: Loaders now have a specific "top level asset type", which makes returning the top-level asset simpler and statically typed. * **Basic Image Settings and Processing**: Image assets can now be processed into the gpu-friendly Basic Universal format. The ImageLoader now has a setting to define what format the image should be loaded as. Note that this is just a minimal MVP ... plenty of additional work to do here. To demo this, enable the `basis-universal` feature and turn on asset processing. * **Simpler Audio Play / AudioSink API**: Asset handle providers are cloneable, which means the Audio resource can mint its own handles. This means you can now do `let sink_handle = audio.play(music)` instead of `let sink_handle = audio_sinks.get_handle(audio.play(music))`. Note that this might still be replaced by https://github.com/bevyengine/bevy/pull/8424. **Removed Handle Casting From Engine Features**: Ex: FontAtlases no longer use casting between handle types ## Using The New Asset System ### Normal Unprocessed Asset Loading By default the `AssetPlugin` does not use processing. It behaves pretty much the same way as the old system. If you are defining a custom asset, first derive `Asset`: ```rust #[derive(Asset)] struct Thing { value: String, } ``` Initialize the asset: ```rust app.init_asset:<Thing>() ``` Implement a new `AssetLoader` for it: ```rust #[derive(Default)] struct ThingLoader; #[derive(Serialize, Deserialize, Default)] pub struct ThingSettings { some_setting: bool, } impl AssetLoader for ThingLoader { type Asset = Thing; type Settings = ThingSettings; fn load<'a>( &'a self, reader: &'a mut Reader, settings: &'a ThingSettings, load_context: &'a mut LoadContext, ) -> BoxedFuture<'a, Result<Thing, anyhow::Error>> { Box::pin(async move { let mut bytes = Vec::new(); reader.read_to_end(&mut bytes).await?; // convert bytes to value somehow Ok(Thing { value }) }) } fn extensions(&self) -> &[&str] { &["thing"] } } ``` Note that this interface will get much cleaner once Rust gets support for async traits. `Reader` is an async futures_io::AsyncRead. You can stream bytes as they come in or read them all into a `Vec<u8>`, depending on the context. You can use `let handle = load_context.load(path)` to kick off a dependency load, retrieve a handle, and register the dependency for the asset. Then just register the loader in your Bevy app: ```rust app.init_asset_loader::<ThingLoader>() ``` Now just add your `Thing` asset files into the `assets` folder and load them like this: ```rust fn system(asset_server: Res<AssetServer>) { let handle = Handle<Thing> = asset_server.load("cool.thing"); } ``` You can check load states directly via the asset server: ```rust if asset_server.load_state(&handle) == LoadState::Loaded { } ``` You can also listen for events: ```rust fn system(mut events: EventReader<AssetEvent<Thing>>, handle: Res<SomeThingHandle>) { for event in events.iter() { if event.is_loaded_with_dependencies(&handle) { } } } ``` Note the new `AssetEvent::LoadedWithDependencies`, which only fires when the asset is loaded _and_ all dependencies (and their dependencies) have loaded. Unlike the old asset system, for a given asset path all `Handle<T>` values point to the same underlying Arc. This means Handles can cheaply hold more asset information, such as the AssetPath: ```rust // prints the AssetPath of the handle info!("{:?}", handle.path()) ``` ### Processed Assets Asset processing can be enabled via the `AssetPlugin`. When developing Bevy Apps with processed assets, do this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev())) ``` This runs the `AssetProcessor` in the background with hot-reloading. It reads assets from the `assets` folder, processes them, and writes them to the `.imported_assets` folder. Asset loads in the Bevy App will wait for a processed version of the asset to become available. If an asset in the `assets` folder changes, it will be reprocessed and hot-reloaded in the Bevy App. When deploying processed Bevy apps, do this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::processed())) ``` This does not run the `AssetProcessor` in the background. It behaves like `AssetPlugin::unprocessed()`, but reads assets from `.imported_assets`. When the `AssetProcessor` is running, it will populate sibling `.meta` files for assets in the `assets` folder. Meta files for assets that do not have a processor configured look like this: ```rust ( meta_format_version: "1.0", asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: FromExtension, ), ), ) ``` This is metadata for an image asset. For example, if you have `assets/my_sprite.png`, this could be the metadata stored at `assets/my_sprite.png.meta`. Meta files are totally optional. If no metadata exists, the default settings will be used. In short, this file says "load this asset with the ImageLoader and use the file extension to determine the image type". This type of meta file is supported in all AssetPlugin modes. If in `Unprocessed` mode, the asset (with the meta settings) will be loaded directly. If in `ProcessedDev` mode, the asset file will be copied directly to the `.imported_assets` folder. The meta will also be copied directly to the `.imported_assets` folder, but with one addition: ```rust ( meta_format_version: "1.0", processed_info: Some(( hash: 12415480888597742505, full_hash: 14344495437905856884, process_dependencies: [], )), asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: FromExtension, ), ), ) ``` `processed_info` contains `hash` (a direct hash of the asset and meta bytes), `full_hash` (a hash of `hash` and the hashes of all `process_dependencies`), and `process_dependencies` (the `path` and `full_hash` of every process_dependency). A "process dependency" is an asset dependency that is _directly_ used when processing the asset. Images do not have process dependencies, so this is empty. When the processor is enabled, you can use the `Process` metadata config: ```rust ( meta_format_version: "1.0", asset: Process( processor: "bevy_asset::processor::process::LoadAndSave<bevy_render::texture::image_loader::ImageLoader, bevy_render::texture::compressed_image_saver::CompressedImageSaver>", settings: ( loader_settings: ( format: FromExtension, ), saver_settings: ( generate_mipmaps: true, ), ), ), ) ``` This configures the asset to use the `LoadAndSave` processor, which runs an AssetLoader and feeds the result into an AssetSaver (which saves the given Asset and defines a loader to load it with). (for terseness LoadAndSave will likely get a shorter/friendlier type name when [Stable Type Paths](#7184) lands). `LoadAndSave` is likely to be the most common processor type, but arbitrary processors are supported. `CompressedImageSaver` saves an `Image` in the Basis Universal format and configures the ImageLoader to load it as basis universal. The `AssetProcessor` will read this meta, run it through the LoadAndSave processor, and write the basis-universal version of the image to `.imported_assets`. The final metadata will look like this: ```rust ( meta_format_version: "1.0", processed_info: Some(( hash: 905599590923828066, full_hash: 9948823010183819117, process_dependencies: [], )), asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: Format(Basis), ), ), ) ``` To try basis-universal processing out in Bevy examples, (for example `sprite.rs`), change `add_plugins(DefaultPlugins)` to `add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev()))` and run with the `basis-universal` feature enabled: `cargo run --features=basis-universal --example sprite`. To create a custom processor, there are two main paths: 1. Use the `LoadAndSave` processor with an existing `AssetLoader`. Implement the `AssetSaver` trait, register the processor using `asset_processor.register_processor::<LoadAndSave<ImageLoader, CompressedImageSaver>>(image_saver.into())`. 2. Implement the `Process` trait directly and register it using: `asset_processor.register_processor(thing_processor)`. You can configure default processors for file extensions like this: ```rust asset_processor.set_default_processor::<ThingProcessor>("thing") ``` There is one more metadata type to be aware of: ```rust ( meta_format_version: "1.0", asset: Ignore, ) ``` This will ignore the asset during processing / prevent it from being written to `.imported_assets`. The AssetProcessor stores a transaction log at `.imported_assets/log` and uses it to gracefully recover from unexpected stops. This means you can force-quit the processor (and Bevy Apps running the processor in parallel) at arbitrary times! `.imported_assets` is "local state". It should _not_ be checked into source control. It should also be considered "read only". In practice, you _can_ modify processed assets and processed metadata if you really need to test something. But those modifications will not be represented in the hashes of the assets, so the processed state will be "out of sync" with the source assets. The processor _will not_ fix this for you. Either revert the change after you have tested it, or delete the processed files so they can be re-populated. ## Open Questions There are a number of open questions to be discussed. We should decide if they need to be addressed in this PR and if so, how we will address them: ### Implied Dependencies vs Dependency Enumeration There are currently two ways to populate asset dependencies: * **Implied via AssetLoaders**: if an AssetLoader loads an asset (and retrieves a handle), a dependency is added to the list. * **Explicit via the optional Asset::visit_dependencies**: if `server.load_asset(my_asset)` is called, it will call `my_asset.visit_dependencies`, which will grab dependencies that have been manually defined for the asset via the Asset trait impl (which can be derived). This means that defining explicit dependencies is optional for "loaded assets". And the list of dependencies is always accurate because loaders can only produce Handles if they register dependencies. If an asset was loaded with an AssetLoader, it only uses the implied dependencies. If an asset was created at runtime and added with `asset_server.load_asset(MyAsset)`, it will use `Asset::visit_dependencies`. However this can create a behavior mismatch between loaded assets and equivalent "created at runtime" assets if `Assets::visit_dependencies` doesn't exactly match the dependencies produced by the AssetLoader. This behavior mismatch can be resolved by completely removing "implied loader dependencies" and requiring `Asset::visit_dependencies` to supply dependency data. But this creates two problems: * It makes defining loaded assets harder and more error prone: Devs must remember to manually annotate asset dependencies with `#[dependency]` when deriving `Asset`. For more complicated assets (such as scenes), the derive likely wouldn't be sufficient and a manual `visit_dependencies` impl would be required. * Removes the ability to immediately kick off dependency loads: When AssetLoaders retrieve a Handle, they also immediately kick off an asset load for the handle, which means it can start loading in parallel _before_ the asset finishes loading. For large assets, this could be significant. (although this could be mitigated for processed assets if we store dependencies in the processed meta file and load them ahead of time) ### Eager ProcessorDev Asset Loading I made a controversial call in the interest of fast startup times ("time to first pixel") for the "processor dev mode configuration". When initializing the AssetProcessor, current processed versions of unchanged assets are yielded immediately, even if their dependencies haven't been checked yet for reprocessing. This means that non-current-state-of-filesystem-but-previously-valid assets might be returned to the App first, then hot-reloaded if/when their dependencies change and the asset is reprocessed. Is this behavior desirable? There is largely one alternative: do not yield an asset from the processor to the app until all of its dependencies have been checked for changes. In some common cases (load dependency has not changed since last run) this will increase startup time. The main question is "by how much" and is that slower startup time worth it in the interest of only yielding assets that are true to the current state of the filesystem. Should this be configurable? I'm starting to think we should only yield an asset after its (historical) dependencies have been checked for changes + processed as necessary, but I'm curious what you all think. ### Paths Are Currently The Only Canonical ID / Do We Want Asset UUIDs? In this implementation AssetPaths are the only canonical asset identifier (just like the previous Bevy Asset system and Godot). Moving assets will result in re-scans (and currently reprocessing, although reprocessing can easily be avoided with some changes). Asset renames/moves will break code and assets that rely on specific paths, unless those paths are fixed up. Do we want / need "stable asset uuids"? Introducing them is very possible: 1. Generate a UUID and include it in .meta files 2. Support UUID in AssetPath 3. Generate "asset indices" which are loaded on startup and map UUIDs to paths. 4 (maybe). Consider only supporting UUIDs for processed assets so we can generate quick-to-load indices instead of scanning meta files. The main "pro" is that assets referencing UUIDs don't need to be migrated when a path changes. The main "con" is that UUIDs cannot be "lazily resolved" like paths. They need a full view of all assets to answer the question "does this UUID exist". Which means UUIDs require the AssetProcessor to fully finish startup scans before saying an asset doesnt exist. And they essentially require asset pre-processing to use in apps, because scanning all asset metadata files at runtime to resolve a UUID is not viable for medium-to-large apps. It really requires a pre-generated UUID index, which must be loaded before querying for assets. I personally think this should be investigated in a separate PR. Paths aren't going anywhere ... _everyone_ uses filesystems (and filesystem-like apis) to manage their asset source files. I consider them permanent canonical asset information. Additionally, they behave well for both processed and unprocessed asset modes. Given that Bevy is supporting both, this feels like the right canonical ID to start with. UUIDS (and maybe even other indexed-identifier types) can be added later as necessary. ### Folder / File Naming Conventions All asset processing config currently lives in the `.imported_assets` folder. The processor transaction log is in `.imported_assets/log`. Processed assets are added to `.imported_assets/Default`, which will make migrating to processed asset profiles (ex: a `.imported_assets/Mobile` profile) a non-breaking change. It also allows us to create top-level files like `.imported_assets/log` without it being interpreted as an asset. Meta files currently have a `.meta` suffix. Do we like these names and conventions? ### Should the `AssetPlugin::processed_dev` configuration enable `watch_for_changes` automatically? Currently it does (which I think makes sense), but it does make it the only configuration that enables watch_for_changes by default. ### Discuss on_loaded High Level Interface: This PR includes a very rough "proof of concept" `on_loaded` system adapter that uses the `LoadedWithDependencies` event in combination with `asset_server.load_asset` dependency tracking to support this pattern ```rust fn main() { App::new() .init_asset::<MyAssets>() .add_systems(Update, on_loaded(create_array_texture)) .run(); } #[derive(Asset, Clone)] struct MyAssets { #[dependency] picture_of_my_cat: Handle<Image>, #[dependency] picture_of_my_other_cat: Handle<Image>, } impl FromWorld for ArrayTexture { fn from_world(world: &mut World) -> Self { picture_of_my_cat: server.load("meow.png"), picture_of_my_other_cat: server.load("meeeeeeeow.png"), } } fn spawn_cat(In(my_assets): In<MyAssets>, mut commands: Commands) { commands.spawn(SpriteBundle { texture: my_assets.picture_of_my_cat.clone(), ..default() }); commands.spawn(SpriteBundle { texture: my_assets.picture_of_my_other_cat.clone(), ..default() }); } ``` The implementation is _very_ rough. And it is currently unsafe because `bevy_ecs` doesn't expose some internals to do this safely from inside `bevy_asset`. There are plenty of unanswered questions like: * "do we add a Loadable" derive? (effectively automate the FromWorld implementation above) * Should `MyAssets` even be an Asset? (largely implemented this way because it elegantly builds on `server.load_asset(MyAsset { .. })` dependency tracking). We should think hard about what our ideal API looks like (and if this is a pattern we want to support). Not necessarily something we need to solve in this PR. The current `on_loaded` impl should probably be removed from this PR before merging. ## Clarifying Questions ### What about Assets as Entities? This Bevy Asset V2 proposal implementation initially stored Assets as ECS Entities. Instead of `AssetId<T>` + the `Assets<T>` resource it used `Entity` as the asset id and Asset values were just ECS components. There are plenty of compelling reasons to do this: 1. Easier to inline assets in Bevy Scenes (as they are "just" normal entities + components) 2. More flexible queries: use the power of the ECS to filter assets (ex: `Query<Mesh, With<Tree>>`). 3. Extensible. Users can add arbitrary component data to assets. 4. Things like "component visualization tools" work out of the box to visualize asset data. However Assets as Entities has a ton of caveats right now: * We need to be able to allocate entity ids without a direct World reference (aka rework id allocator in Entities ... i worked around this in my prototypes by just pre allocating big chunks of entities) * We want asset change events in addition to ECS change tracking ... how do we populate them when mutations can come from anywhere? Do we use Changed queries? This would require iterating over the change data for all assets every frame. Is this acceptable or should we implement a new "event based" component change detection option? * Reconciling manually created assets with asset-system managed assets has some nuance (ex: are they "loaded" / do they also have that component metadata?) * "how do we handle "static" / default entity handles" (ties in to the Entity Indices discussion: https://github.com/bevyengine/bevy/discussions/8319). This is necessary for things like "built in" assets and default handles in things like SpriteBundle. * Storing asset information as a component makes it easy to "invalidate" asset state by removing the component (or forcing modifications). Ideally we have ways to lock this down (some combination of Rust type privacy and ECS validation) In practice, how we store and identify assets is a reasonably superficial change (porting off of Assets as Entities and implementing dedicated storage + ids took less than a day). So once we sort out the remaining challenges the flip should be straightforward. Additionally, I do still have "Assets as Entities" in my commit history, so we can reuse that work. I personally think "assets as entities" is a good endgame, but it also doesn't provide _significant_ value at the moment and it certainly isn't ready yet with the current state of things. ### Why not Distill? [Distill](https://github.com/amethyst/distill) is a high quality fully featured asset system built in Rust. It is very natural to ask "why not just use Distill?". It is also worth calling out that for awhile, [we planned on adopting Distill / I signed off on it](https://github.com/bevyengine/bevy/issues/708). However I think Bevy has a number of constraints that make Distill adoption suboptimal: * **Architectural Simplicity:** * Distill's processor requires an in-memory database (lmdb) and RPC networked API (using Cap'n Proto). Each of these introduces API complexity that increases maintenance burden and "code grokability". Ignoring tests, documentation, and examples, Distill has 24,237 lines of Rust code (including generated code for RPC + database interactions). If you ignore generated code, it has 11,499 lines. * Bevy builds the AssetProcessor and AssetServer using pluggable AssetReader/AssetWriter Rust traits with simple io interfaces. They do not necessitate databases or RPC interfaces (although Readers/Writers could use them if that is desired). Bevy Asset V2 (at the time of writing this PR) is 5,384 lines of Rust code (ignoring tests, documentation, and examples). Grain of salt: Distill does have more features currently (ex: Asset Packing, GUIDS, remote-out-of-process asset processor). I do plan to implement these features in Bevy Asset V2 and I personally highly doubt they will meaningfully close the 6115 lines-of-code gap. * This complexity gap (which while illustrated by lines of code, is much bigger than just that) is noteworthy to me. Bevy should be hackable and there are pillars of Distill that are very hard to understand and extend. This is a matter of opinion (and Bevy Asset V2 also has complicated areas), but I think Bevy Asset V2 is much more approachable for the average developer. * Necessary disclaimer: counting lines of code is an extremely rough complexity metric. Read the code and form your own opinions. * **Optional Asset Processing:** Not all Bevy Apps (or Bevy App developers) need / want asset preprocessing. Processing increases the complexity of the development environment by introducing things like meta files, imported asset storage, running processors in the background, waiting for processing to finish, etc. Distill _requires_ preprocessing to work. With Bevy Asset V2 processing is fully opt-in. The AssetServer isn't directly aware of asset processors at all. AssetLoaders only care about converting bytes to runtime Assets ... they don't know or care if the bytes were pre-processed or not. Processing is "elegantly" (forgive my self-congratulatory phrasing) layered on top and builds on the existing Asset system primitives. * **Direct Filesystem Access to Processed Asset State:** Distill stores processed assets in a database. This makes debugging / inspecting the processed outputs harder (either requires special tooling to query the database or they need to be "deployed" to be inspected). Bevy Asset V2, on the other hand, stores processed assets in the filesystem (by default ... this is configurable). This makes interacting with the processed state more natural. Note that both Godot and Unity's new asset system store processed assets in the filesystem. * **Portability**: Because Distill's processor uses lmdb and RPC networking, it cannot be run on certain platforms (ex: lmdb is a non-rust dependency that cannot run on the web, some platforms don't support running network servers). Bevy should be able to process assets everywhere (ex: run the Bevy Editor on the web, compile + process shaders on mobile, etc). Distill does partially mitigate this problem by supporting "streaming" assets via the RPC protocol, but this is not a full solve from my perspective. And Bevy Asset V2 can (in theory) also stream assets (without requiring RPC, although this isn't implemented yet) Note that I _do_ still think Distill would be a solid asset system for Bevy. But I think the approach in this PR is a better solve for Bevy's specific "asset system requirements". ### Doesn't async-fs just shim requests to "sync" `std::fs`? What is the point? "True async file io" has limited / spotty platform support. async-fs (and the rust async ecosystem generally ... ex Tokio) currently use async wrappers over std::fs that offload blocking requests to separate threads. This may feel unsatisfying, but it _does_ still provide value because it prevents our task pools from blocking on file system operations (which would prevent progress when there are many tasks to do, but all threads in a pool are currently blocking on file system ops). Additionally, using async APIs for our AssetReaders and AssetWriters also provides value because we can later add support for "true async file io" for platforms that support it. _And_ we can implement other "true async io" asset backends (such as networked asset io). ## Draft TODO - [x] Fill in missing filesystem event APIs: file removed event (which is expressed as dangling RenameFrom events in some cases), file/folder renamed event - [x] Assets without loaders are not moved to the processed folder. This breaks things like referenced `.bin` files for GLTFs. This should be configurable per-non-asset-type. - [x] Initial implementation of Reflect and FromReflect for Handle. The "deserialization" parity bar is low here as this only worked with static UUIDs in the old impl ... this is a non-trivial problem. Either we add a Handle::AssetPath variant that gets "upgraded" to a strong handle on scene load or we use a separate AssetRef type for Bevy scenes (which is converted to a runtime Handle on load). This deserves its own discussion in a different pr. - [x] Populate read_asset_bytes hash when run by the processor (a bit of a special case .. when run by the processor the processed meta will contain the hash so we don't need to compute it on the spot, but we don't want/need to read the meta when run by the main AssetServer) - [x] Delay hot reloading: currently filesystem events are handled immediately, which creates timing issues in some cases. For example hot reloading images can sometimes break because the image isn't finished writing. We should add a delay, likely similar to the [implementation in this PR](https://github.com/bevyengine/bevy/pull/8503). - [x] Port old platform-specific AssetIo implementations to the new AssetReader interface (currently missing Android and web) - [x] Resolve on_loaded unsafety (either by removing the API entirely or removing the unsafe) - [x] Runtime loader setting overrides - [x] Remove remaining unwraps that should be error-handled. There are number of TODOs here - [x] Pretty AssetPath Display impl - [x] Document more APIs - [x] Resolve spurious "reloading because it has changed" events (to repro run load_gltf with `processed_dev()`) - [x] load_dependency hot reloading currently only works for processed assets. If processing is disabled, load_dependency changes are not hot reloaded. - [x] Replace AssetInfo dependency load/fail counters with `loading_dependencies: HashSet<UntypedAssetId>` to prevent reloads from (potentially) breaking counters. Storing this will also enable "dependency reloaded" events (see [Next Steps](#next-steps)) - [x] Re-add filesystem watcher cargo feature gate (currently it is not optional) - [ ] Migration Guide - [ ] Changelog ## Followup TODO - [ ] Replace "eager unchanged processed asset loading" behavior with "don't returned unchanged processed asset until dependencies have been checked". - [ ] Add true `Ignore` AssetAction that does not copy the asset to the imported_assets folder. - [ ] Finish "live asset unloading" (ex: free up CPU asset memory after uploading an image to the GPU), rethink RenderAssets, and port renderer features. The `Assets` collection uses `Option<T>` for asset storage to support its removal. (1) the Option might not actually be necessary ... might be able to just remove from the collection entirely (2) need to finalize removal apis - [ ] Try replacing the "channel based" asset id recycling with something a bit more efficient (ex: we might be able to use raw atomic ints with some cleverness) - [ ] Consider adding UUIDs to processed assets (scoped just to helping identify moved assets ... not exposed to load queries ... see [Next Steps](#next-steps)) - [ ] Store "last modified" source asset and meta timestamps in processed meta files to enable skipping expensive hashing when the file wasn't changed - [ ] Fix "slow loop" handle drop fix - [ ] Migrate to TypeName - [x] Handle "loader preregistration". See #9429 ## Next Steps * **Configurable per-type defaults for AssetMeta**: It should be possible to add configuration like "all png image meta should default to using nearest sampling" (currently this hard-coded per-loader/processor Settings::default() impls). Also see the "Folder Meta" bullet point. * **Avoid Reprocessing on Asset Renames / Moves**: See the "canonical asset ids" discussion in [Open Questions](#open-questions) and the relevant bullet point in [Draft TODO](#draft-todo). Even without canonical ids, folder renames could avoid reprocessing in some cases. * **Multiple Asset Sources**: Expand AssetPath to support "asset source names" and support multiple AssetReaders in the asset server (ex: `webserver://some_path/image.png` backed by an Http webserver AssetReader). The "default" asset reader would use normal `some_path/image.png` paths. Ideally this works in combination with multiple AssetWatchers for hot-reloading * **Stable Type Names**: this pr removes the TypeUuid requirement from assets in favor of `std::any::type_name`. This makes defining assets easier (no need to generate a new uuid / use weird proc macro syntax). It also makes reading meta files easier (because things have "friendly names"). We also use type names for components in scene files. If they are good enough for components, they are good enough for assets. And consistency across Bevy pillars is desirable. However, `std::any::type_name` is not guaranteed to be stable (although in practice it is). We've developed a [stable type path](https://github.com/bevyengine/bevy/pull/7184) to resolve this, which should be adopted when it is ready. * **Command Line Interface**: It should be possible to run the asset processor in a separate process from the command line. This will also require building a network-server-backed AssetReader to communicate between the app and the processor. We've been planning to build a "bevy cli" for awhile. This seems like a good excuse to build it. * **Asset Packing**: This is largely an additive feature, so it made sense to me to punt this until we've laid the foundations in this PR. * **Per-Platform Processed Assets**: It should be possible to generate assets for multiple platforms by supporting multiple "processor profiles" per asset (ex: compress with format X on PC and Y on iOS). I think there should probably be arbitrary "profiles" (which can be separate from actual platforms), which are then assigned to a given platform when generating the final asset distribution for that platform. Ex: maybe devs want a "Mobile" profile that is shared between iOS and Android. Or a "LowEnd" profile shared between web and mobile. * **Versioning and Migrations**: Assets, Loaders, Savers, and Processors need to have versions to determine if their schema is valid. If an asset / loader version is incompatible with the current version expected at runtime, the processor should be able to migrate them. I think we should try using Bevy Reflect for this, as it would allow us to load the old version as a dynamic Reflect type without actually having the old Rust type. It would also allow us to define "patches" to migrate between versions (Bevy Reflect devs are currently working on patching). The `.meta` file already has its own format version. Migrating that to new versions should also be possible. * **Real Copy-on-write AssetPaths**: Rust's actual Cow (clone-on-write type) currently used by AssetPath can still result in String clones that aren't actually necessary (cloning an Owned Cow clones the contents). Bevy's asset system requires cloning AssetPaths in a number of places, which result in actual clones of the internal Strings. This is not efficient. AssetPath internals should be reworked to exhibit truer cow-like-behavior that reduces String clones to the absolute minimum. * **Consider processor-less processing**: In theory the AssetServer could run processors "inline" even if the background AssetProcessor is disabled. If we decide this is actually desirable, we could add this. But I don't think its a priority in the short or medium term. * **Pre-emptive dependency loading**: We could encode dependencies in processed meta files, which could then be used by the Asset Server to kick of dependency loads as early as possible (prior to starting the actual asset load). Is this desirable? How much time would this save in practice? * **Optimize Processor With UntypedAssetIds**: The processor exclusively uses AssetPath to identify assets currently. It might be possible to swap these out for UntypedAssetIds in some places, which are smaller / cheaper to hash and compare. * **One to Many Asset Processing**: An asset source file that produces many assets currently must be processed into a single "processed" asset source. If labeled assets can be written separately they can each have their own configured savers _and_ they could be loaded more granularly. Definitely worth exploring! * **Automatically Track "Runtime-only" Asset Dependencies**: Right now, tracking "created at runtime" asset dependencies requires adding them via `asset_server.load_asset(StandardMaterial::default())`. I think with some cleverness we could also do this for `materials.add(StandardMaterial::default())`, making tracking work "everywhere". There are challenges here relating to change detection / ensuring the server is made aware of dependency changes. This could be expensive in some cases. * **"Dependency Changed" events**: Some assets have runtime artifacts that need to be re-generated when one of their dependencies change (ex: regenerate a material's bind group when a Texture needs to change). We are generating the dependency graph so we can definitely produce these events. Buuuuut generating these events will have a cost / they could be high frequency for some assets, so we might want this to be opt-in for specific cases. * **Investigate Storing More Information In Handles**: Handles can now store arbitrary information, which makes it cheaper and easier to access. How much should we move into them? Canonical asset load states (via atomics)? (`handle.is_loaded()` would be very cool). Should we store the entire asset and remove the `Assets<T>` collection? (`Arc<RwLock<Option<Image>>>`?) * **Support processing and loading files without extensions**: This is a pretty arbitrary restriction and could be supported with very minimal changes. * **Folder Meta**: It would be nice if we could define per folder processor configuration defaults (likely in a `.meta` or `.folder_meta` file). Things like "default to linear filtering for all Images in this folder". * **Replace async_broadcast with event-listener?** This might be approximately drop-in for some uses and it feels more light weight * **Support Running the AssetProcessor on the Web**: Most of the hard work is done here, but there are some easy straggling TODOs (make the transaction log an interface instead of a direct file writer so we can write a web storage backend, implement an AssetReader/AssetWriter that reads/writes to something like LocalStorage). * **Consider identifying and preventing circular dependencies**: This is especially important for "processor dependencies", as processing will silently never finish in these cases. * **Built-in/Inlined Asset Hot Reloading**: This PR regresses "built-in/inlined" asset hot reloading (previously provided by the DebugAssetServer). I'm intentionally punting this because I think it can be cleanly implemented with "multiple asset sources" by registering a "debug asset source" (ex: `debug://bevy_pbr/src/render/pbr.wgsl` asset paths) in combination with an AssetWatcher for that asset source and support for "manually loading pats with asset bytes instead of AssetReaders". The old DebugAssetServer was quite nasty and I'd love to avoid that hackery going forward. * **Investigate ways to remove double-parsing meta files**: Parsing meta files currently involves parsing once with "minimal" versions of the meta file to extract the type name of the loader/processor config, then parsing again to parse the "full" meta. This is suboptimal. We should be able to define custom deserializers that (1) assume the loader/processor type name comes first (2) dynamically looks up the loader/processor registrations to deserialize settings in-line (similar to components in the bevy scene format). Another alternative: deserialize as dynamic Reflect objects and then convert. * **More runtime loading configuration**: Support using the Handle type as a hint to select an asset loader (instead of relying on AssetPath extensions) * **More high level Processor trait implementations**: For example, it might be worth adding support for arbitrary chains of "asset transforms" that modify an in-memory asset representation between loading and saving. (ex: load a Mesh, run a `subdivide_mesh` transform, followed by a `flip_normals` transform, then save the mesh to an efficient compressed format). * **Bevy Scene Handle Deserialization**: (see the relevant [Draft TODO item](#draft-todo) for context) * **Explore High Level Load Interfaces**: See [this discussion](#discuss-on_loaded-high-level-interface) for one prototype. * **Asset Streaming**: It would be great if we could stream Assets (ex: stream a long video file piece by piece) * **ID Exchanging**: In this PR Asset Handles/AssetIds are bigger than they need to be because they have a Uuid enum variant. If we implement an "id exchanging" system that trades Uuids for "efficient runtime ids", we can cut down on the size of AssetIds, making them more efficient. This has some open design questions, such as how to spawn entities with "default" handle values (as these wouldn't have access to the exchange api in the current system). * **Asset Path Fixup Tooling**: Assets that inline asset paths inside them will break when an asset moves. The asset system provides the functionality to detect when paths break. We should build a framework that enables formats to define "path migrations". This is especially important for scene files. For editor-generated files, we should also consider using UUIDs (see other bullet point) to avoid the need to migrate in these cases. --------- Co-authored-by: BeastLe9enD <beastle9end@outlook.de> Co-authored-by: Mike <mike.hsu@gmail.com> Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com>
2023-09-07 02:07:27 +00:00
# Enables watching the filesystem for Bevy Asset hot-reloading
Multiple Asset Sources (#9885) This adds support for **Multiple Asset Sources**. You can now register a named `AssetSource`, which you can load assets from like you normally would: ```rust let shader: Handle<Shader> = asset_server.load("custom_source://path/to/shader.wgsl"); ``` Notice that `AssetPath` now supports `some_source://` syntax. This can now be accessed through the `asset_path.source()` accessor. Asset source names _are not required_. If one is not specified, the default asset source will be used: ```rust let shader: Handle<Shader> = asset_server.load("path/to/shader.wgsl"); ``` The behavior of the default asset source has not changed. Ex: the `assets` folder is still the default. As referenced in #9714 ## Why? **Multiple Asset Sources** enables a number of often-asked-for scenarios: * **Loading some assets from other locations on disk**: you could create a `config` asset source that reads from the OS-default config folder (not implemented in this PR) * **Loading some assets from a remote server**: you could register a new `remote` asset source that reads some assets from a remote http server (not implemented in this PR) * **Improved "Binary Embedded" Assets**: we can use this system for "embedded-in-binary assets", which allows us to replace the old `load_internal_asset!` approach, which couldn't support asset processing, didn't support hot-reloading _well_, and didn't make embedded assets accessible to the `AssetServer` (implemented in this pr) ## Adding New Asset Sources An `AssetSource` is "just" a collection of `AssetReader`, `AssetWriter`, and `AssetWatcher` entries. You can configure new asset sources like this: ```rust app.register_asset_source( "other", AssetSource::build() .with_reader(|| Box::new(FileAssetReader::new("other"))) ) ) ``` Note that `AssetSource` construction _must_ be repeatable, which is why a closure is accepted. `AssetSourceBuilder` supports `with_reader`, `with_writer`, `with_watcher`, `with_processed_reader`, `with_processed_writer`, and `with_processed_watcher`. Note that the "asset source" system replaces the old "asset providers" system. ## Processing Multiple Sources The `AssetProcessor` now supports multiple asset sources! Processed assets can refer to assets in other sources and everything "just works". Each `AssetSource` defines an unprocessed and processed `AssetReader` / `AssetWriter`. Currently this is all or nothing for a given `AssetSource`. A given source is either processed or it is not. Later we might want to add support for "lazy asset processing", where an `AssetSource` (such as a remote server) can be configured to only process assets that are directly referenced by local assets (in order to save local disk space and avoid doing extra work). ## A new `AssetSource`: `embedded` One of the big features motivating **Multiple Asset Sources** was improving our "embedded-in-binary" asset loading. To prove out the **Multiple Asset Sources** implementation, I chose to build a new `embedded` `AssetSource`, which replaces the old `load_interal_asset!` system. The old `load_internal_asset!` approach had a number of issues: * The `AssetServer` was not aware of (or capable of loading) internal assets. * Because internal assets weren't visible to the `AssetServer`, they could not be processed (or used by assets that are processed). This would prevent things "preprocessing shaders that depend on built in Bevy shaders", which is something we desperately need to start doing. * Each "internal asset" needed a UUID to be defined in-code to reference it. This was very manual and toilsome. The new `embedded` `AssetSource` enables the following pattern: ```rust // Called in `crates/bevy_pbr/src/render/mesh.rs` embedded_asset!(app, "mesh.wgsl"); // later in the app let shader: Handle<Shader> = asset_server.load("embedded://bevy_pbr/render/mesh.wgsl"); ``` Notice that this always treats the crate name as the "root path", and it trims out the `src` path for brevity. This is generally predictable, but if you need to debug you can use the new `embedded_path!` macro to get a `PathBuf` that matches the one used by `embedded_asset`. You can also reference embedded assets in arbitrary assets, such as WGSL shaders: ```rust #import "embedded://bevy_pbr/render/mesh.wgsl" ``` This also makes `embedded` assets go through the "normal" asset lifecycle. They are only loaded when they are actually used! We are also discussing implicitly converting asset paths to/from shader modules, so in the future (not in this PR) you might be able to load it like this: ```rust #import bevy_pbr::render::mesh::Vertex ``` Compare that to the old system! ```rust pub const MESH_SHADER_HANDLE: Handle<Shader> = Handle::weak_from_u128(3252377289100772450); load_internal_asset!(app, MESH_SHADER_HANDLE, "mesh.wgsl", Shader::from_wgsl); // The mesh asset is the _only_ accessible via MESH_SHADER_HANDLE and _cannot_ be loaded via the AssetServer. ``` ## Hot Reloading `embedded` You can enable `embedded` hot reloading by enabling the `embedded_watcher` cargo feature: ``` cargo run --features=embedded_watcher ``` ## Improved Hot Reloading Workflow First: the `filesystem_watcher` cargo feature has been renamed to `file_watcher` for brevity (and to match the `FileAssetReader` naming convention). More importantly, hot asset reloading is no longer configured in-code by default. If you enable any asset watcher feature (such as `file_watcher` or `rust_source_watcher`), asset watching will be automatically enabled. This removes the need to _also_ enable hot reloading in your app code. That means you can replace this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::default().watch_for_changes())) ``` with this: ```rust app.add_plugins(DefaultPlugins) ``` If you want to hot reload assets in your app during development, just run your app like this: ``` cargo run --features=file_watcher ``` This means you can use the same code for development and deployment! To deploy an app, just don't include the watcher feature ``` cargo build --release ``` My intent is to move to this approach for pretty much all dev workflows. In a future PR I would like to replace `AssetMode::ProcessedDev` with a `runtime-processor` cargo feature. We could then group all common "dev" cargo features under a single `dev` feature: ```sh # this would enable file_watcher, embedded_watcher, runtime-processor, and more cargo run --features=dev ``` ## AssetMode `AssetPlugin::Unprocessed`, `AssetPlugin::Processed`, and `AssetPlugin::ProcessedDev` have been replaced with an `AssetMode` field on `AssetPlugin`. ```rust // before app.add_plugins(DefaultPlugins.set(AssetPlugin::Processed { /* fields here */ }) // after app.add_plugins(DefaultPlugins.set(AssetPlugin { mode: AssetMode::Processed, ..default() }) ``` This aligns `AssetPlugin` with our other struct-like plugins. The old "source" and "destination" `AssetProvider` fields in the enum variants have been replaced by the "asset source" system. You no longer need to configure the AssetPlugin to "point" to custom asset providers. ## AssetServerMode To improve the implementation of **Multiple Asset Sources**, `AssetServer` was made aware of whether or not it is using "processed" or "unprocessed" assets. You can check that like this: ```rust if asset_server.mode() == AssetServerMode::Processed { /* do something */ } ``` Note that this refactor should also prepare the way for building "one to many processed output files", as it makes the server aware of whether it is loading from processed or unprocessed sources. Meaning we can store and read processed and unprocessed assets differently! ## AssetPath can now refer to folders The "file only" restriction has been removed from `AssetPath`. The `AssetServer::load_folder` API now accepts an `AssetPath` instead of a `Path`, meaning you can load folders from other asset sources! ## Improved AssetPath Parsing AssetPath parsing was reworked to support sources, improve error messages, and to enable parsing with a single pass over the string. `AssetPath::new` was replaced by `AssetPath::parse` and `AssetPath::try_parse`. ## AssetWatcher broken out from AssetReader `AssetReader` is no longer responsible for constructing `AssetWatcher`. This has been moved to `AssetSourceBuilder`. ## Duplicate Event Debouncing Asset V2 already debounced duplicate filesystem events, but this was _input_ events. Multiple input event types can produce the same _output_ `AssetSourceEvent`. Now that we have `embedded_watcher`, which does expensive file io on events, it made sense to debounce output events too, so I added that! This will also benefit the AssetProcessor by preventing integrity checks for duplicate events (and helps keep the noise down in trace logs). ## Next Steps * **Port Built-in Shaders**: Currently the primary (and essentially only) user of `load_interal_asset` in Bevy's source code is "built-in shaders". I chose not to do that in this PR for a few reasons: 1. We need to add the ability to pass shader defs in to shaders via meta files. Some shaders (such as MESH_VIEW_TYPES) need to pass shader def values in that are defined in code. 2. We need to revisit the current shader module naming system. I think we _probably_ want to imply modules from source structure (at least by default). Ideally in a way that can losslessly convert asset paths to/from shader modules (to enable the asset system to resolve modules using the asset server). 3. I want to keep this change set minimal / get this merged first. * **Deprecate `load_internal_asset`**: we can't do that until we do (1) and (2) * **Relative Asset Paths**: This PR significantly increases the need for relative asset paths (which was already pretty high). Currently when loading dependencies, it is assumed to be an absolute path, which means if in an `AssetLoader` you call `context.load("some/path/image.png")` it will assume that is the "default" asset source, _even if the current asset is in a different asset source_. This will cause breakage for AssetLoaders that are not designed to add the current source to whatever paths are being used. AssetLoaders should generally not need to be aware of the name of their current asset source, or need to think about the "current asset source" generally. We should build apis that support relative asset paths and then encourage using relative paths as much as possible (both via api design and docs). Relative paths are also important because they will allow developers to move folders around (even across providers) without reprocessing, provided there is no path breakage.
2023-10-13 23:17:32 +00:00
file_watcher = ["bevy_internal/file_watcher"]
# Enables watching in memory asset providers for Bevy Asset hot-reloading
embedded_watcher = ["bevy_internal/embedded_watcher"]
Bevy Asset V2 (#8624) # Bevy Asset V2 Proposal ## Why Does Bevy Need A New Asset System? Asset pipelines are a central part of the gamedev process. Bevy's current asset system is missing a number of features that make it non-viable for many classes of gamedev. After plenty of discussions and [a long community feedback period](https://github.com/bevyengine/bevy/discussions/3972), we've identified a number missing features: * **Asset Preprocessing**: it should be possible to "preprocess" / "compile" / "crunch" assets at "development time" rather than when the game starts up. This enables offloading expensive work from deployed apps, faster asset loading, less runtime memory usage, etc. * **Per-Asset Loader Settings**: Individual assets cannot define their own loaders that override the defaults. Additionally, they cannot provide per-asset settings to their loaders. This is a huge limitation, as many asset types don't provide all information necessary for Bevy _inside_ the asset. For example, a raw PNG image says nothing about how it should be sampled (ex: linear vs nearest). * **Asset `.meta` files**: assets should have configuration files stored adjacent to the asset in question, which allows the user to configure asset-type-specific settings. These settings should be accessible during the pre-processing phase. Modifying a `.meta` file should trigger a re-processing / re-load of the asset. It should be possible to configure asset loaders from the meta file. * **Processed Asset Hot Reloading**: Changes to processed assets (or their dependencies) should result in re-processing them and re-loading the results in live Bevy Apps. * **Asset Dependency Tracking**: The current bevy_asset has no good way to wait for asset dependencies to load. It punts this as an exercise for consumers of the loader apis, which is unreasonable and error prone. There should be easy, ergonomic ways to wait for assets to load and block some logic on an asset's entire dependency tree loading. * **Runtime Asset Loading**: it should be (optionally) possible to load arbitrary assets dynamically at runtime. This necessitates being able to deploy and run the asset server alongside Bevy Apps on _all platforms_. For example, we should be able to invoke the shader compiler at runtime, stream scenes from sources like the internet, etc. To keep deployed binaries (and startup times) small, the runtime asset server configuration should be configurable with different settings compared to the "pre processor asset server". * **Multiple Backends**: It should be possible to load assets from arbitrary sources (filesystems, the internet, remote asset serves, etc). * **Asset Packing**: It should be possible to deploy assets in compressed "packs", which makes it easier and more efficient to distribute assets with Bevy Apps. * **Asset Handoff**: It should be possible to hold a "live" asset handle, which correlates to runtime data, without actually holding the asset in memory. Ex: it must be possible to hold a reference to a GPU mesh generated from a "mesh asset" without keeping the mesh data in CPU memory * **Per-Platform Processed Assets**: Different platforms and app distributions have different capabilities and requirements. Some platforms need lower asset resolutions or different asset formats to operate within the hardware constraints of the platform. It should be possible to define per-platform asset processing profiles. And it should be possible to deploy only the assets required for a given platform. These features have architectural implications that are significant enough to require a full rewrite. The current Bevy Asset implementation got us this far, but it can take us no farther. This PR defines a brand new asset system that implements most of these features, while laying the foundations for the remaining features to be built. ## Bevy Asset V2 Here is a quick overview of the features introduced in this PR. * **Asset Preprocessing**: Preprocess assets at development time into more efficient (and configurable) representations * **Dependency Aware**: Dependencies required to process an asset are tracked. If an asset's processed dependency changes, it will be reprocessed * **Hot Reprocessing/Reloading**: detect changes to asset source files, reprocess them if they have changed, and then hot-reload them in Bevy Apps. * **Only Process Changes**: Assets are only re-processed when their source file (or meta file) has changed. This uses hashing and timestamps to avoid processing assets that haven't changed. * **Transactional and Reliable**: Uses write-ahead logging (a technique commonly used by databases) to recover from crashes / forced-exits. Whenever possible it avoids full-reprocessing / only uncompleted transactions will be reprocessed. When the processor is running in parallel with a Bevy App, processor asset writes block Bevy App asset reads. Reading metadata + asset bytes is guaranteed to be transactional / correctly paired. * **Portable / Run anywhere / Database-free**: The processor does not rely on an in-memory database (although it uses some database techniques for reliability). This is important because pretty much all in-memory databases have unsupported platforms or build complications. * **Configure Processor Defaults Per File Type**: You can say "use this processor for all files of this type". * **Custom Processors**: The `Processor` trait is flexible and unopinionated. It can be implemented by downstream plugins. * **LoadAndSave Processors**: Most asset processing scenarios can be expressed as "run AssetLoader A, save the results using AssetSaver X, and then load the result using AssetLoader B". For example, load this png image using `PngImageLoader`, which produces an `Image` asset and then save it using `CompressedImageSaver` (which also produces an `Image` asset, but in a compressed format), which takes an `Image` asset as input. This means if you have an `AssetLoader` for an asset, you are already half way there! It also means that you can share AssetSavers across multiple loaders. Because `CompressedImageSaver` accepts Bevy's generic Image asset as input, it means you can also use it with some future `JpegImageLoader`. * **Loader and Saver Settings**: Asset Loaders and Savers can now define their own settings types, which are passed in as input when an asset is loaded / saved. Each asset can define its own settings. * **Asset `.meta` files**: configure asset loaders, their settings, enable/disable processing, and configure processor settings * **Runtime Asset Dependency Tracking** Runtime asset dependencies (ex: if an asset contains a `Handle<Image>`) are tracked by the asset server. An event is emitted when an asset and all of its dependencies have been loaded * **Unprocessed Asset Loading**: Assets do not require preprocessing. They can be loaded directly. A processed asset is just a "normal" asset with some extra metadata. Asset Loaders don't need to know or care about whether or not an asset was processed. * **Async Asset IO**: Asset readers/writers use async non-blocking interfaces. Note that because Rust doesn't yet support async traits, there is a bit of manual Boxing / Future boilerplate. This will hopefully be removed in the near future when Rust gets async traits. * **Pluggable Asset Readers and Writers**: Arbitrary asset source readers/writers are supported, both by the processor and the asset server. * **Better Asset Handles** * **Single Arc Tree**: Asset Handles now use a single arc tree that represents the lifetime of the asset. This makes their implementation simpler, more efficient, and allows us to cheaply attach metadata to handles. Ex: the AssetPath of a handle is now directly accessible on the handle itself! * **Const Typed Handles**: typed handles can be constructed in a const context. No more weird "const untyped converted to typed at runtime" patterns! * **Handles and Ids are Smaller / Faster To Hash / Compare**: Typed `Handle<T>` is now much smaller in memory and `AssetId<T>` is even smaller. * **Weak Handle Usage Reduction**: In general Handles are now considered to be "strong". Bevy features that previously used "weak `Handle<T>`" have been ported to `AssetId<T>`, which makes it statically clear that the features do not hold strong handles (while retaining strong type information). Currently Handle::Weak still exists, but it is very possible that we can remove that entirely. * **Efficient / Dense Asset Ids**: Assets now have efficient dense runtime asset ids, which means we can avoid expensive hash lookups. Assets are stored in Vecs instead of HashMaps. There are now typed and untyped ids, which means we no longer need to store dynamic type information in the ID for typed handles. "AssetPathId" (which was a nightmare from a performance and correctness standpoint) has been entirely removed in favor of dense ids (which are retrieved for a path on load) * **Direct Asset Loading, with Dependency Tracking**: Assets that are defined at runtime can still have their dependencies tracked by the Asset Server (ex: if you create a material at runtime, you can still wait for its textures to load). This is accomplished via the (currently optional) "asset dependency visitor" trait. This system can also be used to define a set of assets to load, then wait for those assets to load. * **Async folder loading**: Folder loading also uses this system and immediately returns a handle to the LoadedFolder asset, which means folder loading no longer blocks on directory traversals. * **Improved Loader Interface**: Loaders now have a specific "top level asset type", which makes returning the top-level asset simpler and statically typed. * **Basic Image Settings and Processing**: Image assets can now be processed into the gpu-friendly Basic Universal format. The ImageLoader now has a setting to define what format the image should be loaded as. Note that this is just a minimal MVP ... plenty of additional work to do here. To demo this, enable the `basis-universal` feature and turn on asset processing. * **Simpler Audio Play / AudioSink API**: Asset handle providers are cloneable, which means the Audio resource can mint its own handles. This means you can now do `let sink_handle = audio.play(music)` instead of `let sink_handle = audio_sinks.get_handle(audio.play(music))`. Note that this might still be replaced by https://github.com/bevyengine/bevy/pull/8424. **Removed Handle Casting From Engine Features**: Ex: FontAtlases no longer use casting between handle types ## Using The New Asset System ### Normal Unprocessed Asset Loading By default the `AssetPlugin` does not use processing. It behaves pretty much the same way as the old system. If you are defining a custom asset, first derive `Asset`: ```rust #[derive(Asset)] struct Thing { value: String, } ``` Initialize the asset: ```rust app.init_asset:<Thing>() ``` Implement a new `AssetLoader` for it: ```rust #[derive(Default)] struct ThingLoader; #[derive(Serialize, Deserialize, Default)] pub struct ThingSettings { some_setting: bool, } impl AssetLoader for ThingLoader { type Asset = Thing; type Settings = ThingSettings; fn load<'a>( &'a self, reader: &'a mut Reader, settings: &'a ThingSettings, load_context: &'a mut LoadContext, ) -> BoxedFuture<'a, Result<Thing, anyhow::Error>> { Box::pin(async move { let mut bytes = Vec::new(); reader.read_to_end(&mut bytes).await?; // convert bytes to value somehow Ok(Thing { value }) }) } fn extensions(&self) -> &[&str] { &["thing"] } } ``` Note that this interface will get much cleaner once Rust gets support for async traits. `Reader` is an async futures_io::AsyncRead. You can stream bytes as they come in or read them all into a `Vec<u8>`, depending on the context. You can use `let handle = load_context.load(path)` to kick off a dependency load, retrieve a handle, and register the dependency for the asset. Then just register the loader in your Bevy app: ```rust app.init_asset_loader::<ThingLoader>() ``` Now just add your `Thing` asset files into the `assets` folder and load them like this: ```rust fn system(asset_server: Res<AssetServer>) { let handle = Handle<Thing> = asset_server.load("cool.thing"); } ``` You can check load states directly via the asset server: ```rust if asset_server.load_state(&handle) == LoadState::Loaded { } ``` You can also listen for events: ```rust fn system(mut events: EventReader<AssetEvent<Thing>>, handle: Res<SomeThingHandle>) { for event in events.iter() { if event.is_loaded_with_dependencies(&handle) { } } } ``` Note the new `AssetEvent::LoadedWithDependencies`, which only fires when the asset is loaded _and_ all dependencies (and their dependencies) have loaded. Unlike the old asset system, for a given asset path all `Handle<T>` values point to the same underlying Arc. This means Handles can cheaply hold more asset information, such as the AssetPath: ```rust // prints the AssetPath of the handle info!("{:?}", handle.path()) ``` ### Processed Assets Asset processing can be enabled via the `AssetPlugin`. When developing Bevy Apps with processed assets, do this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev())) ``` This runs the `AssetProcessor` in the background with hot-reloading. It reads assets from the `assets` folder, processes them, and writes them to the `.imported_assets` folder. Asset loads in the Bevy App will wait for a processed version of the asset to become available. If an asset in the `assets` folder changes, it will be reprocessed and hot-reloaded in the Bevy App. When deploying processed Bevy apps, do this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::processed())) ``` This does not run the `AssetProcessor` in the background. It behaves like `AssetPlugin::unprocessed()`, but reads assets from `.imported_assets`. When the `AssetProcessor` is running, it will populate sibling `.meta` files for assets in the `assets` folder. Meta files for assets that do not have a processor configured look like this: ```rust ( meta_format_version: "1.0", asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: FromExtension, ), ), ) ``` This is metadata for an image asset. For example, if you have `assets/my_sprite.png`, this could be the metadata stored at `assets/my_sprite.png.meta`. Meta files are totally optional. If no metadata exists, the default settings will be used. In short, this file says "load this asset with the ImageLoader and use the file extension to determine the image type". This type of meta file is supported in all AssetPlugin modes. If in `Unprocessed` mode, the asset (with the meta settings) will be loaded directly. If in `ProcessedDev` mode, the asset file will be copied directly to the `.imported_assets` folder. The meta will also be copied directly to the `.imported_assets` folder, but with one addition: ```rust ( meta_format_version: "1.0", processed_info: Some(( hash: 12415480888597742505, full_hash: 14344495437905856884, process_dependencies: [], )), asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: FromExtension, ), ), ) ``` `processed_info` contains `hash` (a direct hash of the asset and meta bytes), `full_hash` (a hash of `hash` and the hashes of all `process_dependencies`), and `process_dependencies` (the `path` and `full_hash` of every process_dependency). A "process dependency" is an asset dependency that is _directly_ used when processing the asset. Images do not have process dependencies, so this is empty. When the processor is enabled, you can use the `Process` metadata config: ```rust ( meta_format_version: "1.0", asset: Process( processor: "bevy_asset::processor::process::LoadAndSave<bevy_render::texture::image_loader::ImageLoader, bevy_render::texture::compressed_image_saver::CompressedImageSaver>", settings: ( loader_settings: ( format: FromExtension, ), saver_settings: ( generate_mipmaps: true, ), ), ), ) ``` This configures the asset to use the `LoadAndSave` processor, which runs an AssetLoader and feeds the result into an AssetSaver (which saves the given Asset and defines a loader to load it with). (for terseness LoadAndSave will likely get a shorter/friendlier type name when [Stable Type Paths](#7184) lands). `LoadAndSave` is likely to be the most common processor type, but arbitrary processors are supported. `CompressedImageSaver` saves an `Image` in the Basis Universal format and configures the ImageLoader to load it as basis universal. The `AssetProcessor` will read this meta, run it through the LoadAndSave processor, and write the basis-universal version of the image to `.imported_assets`. The final metadata will look like this: ```rust ( meta_format_version: "1.0", processed_info: Some(( hash: 905599590923828066, full_hash: 9948823010183819117, process_dependencies: [], )), asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: Format(Basis), ), ), ) ``` To try basis-universal processing out in Bevy examples, (for example `sprite.rs`), change `add_plugins(DefaultPlugins)` to `add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev()))` and run with the `basis-universal` feature enabled: `cargo run --features=basis-universal --example sprite`. To create a custom processor, there are two main paths: 1. Use the `LoadAndSave` processor with an existing `AssetLoader`. Implement the `AssetSaver` trait, register the processor using `asset_processor.register_processor::<LoadAndSave<ImageLoader, CompressedImageSaver>>(image_saver.into())`. 2. Implement the `Process` trait directly and register it using: `asset_processor.register_processor(thing_processor)`. You can configure default processors for file extensions like this: ```rust asset_processor.set_default_processor::<ThingProcessor>("thing") ``` There is one more metadata type to be aware of: ```rust ( meta_format_version: "1.0", asset: Ignore, ) ``` This will ignore the asset during processing / prevent it from being written to `.imported_assets`. The AssetProcessor stores a transaction log at `.imported_assets/log` and uses it to gracefully recover from unexpected stops. This means you can force-quit the processor (and Bevy Apps running the processor in parallel) at arbitrary times! `.imported_assets` is "local state". It should _not_ be checked into source control. It should also be considered "read only". In practice, you _can_ modify processed assets and processed metadata if you really need to test something. But those modifications will not be represented in the hashes of the assets, so the processed state will be "out of sync" with the source assets. The processor _will not_ fix this for you. Either revert the change after you have tested it, or delete the processed files so they can be re-populated. ## Open Questions There are a number of open questions to be discussed. We should decide if they need to be addressed in this PR and if so, how we will address them: ### Implied Dependencies vs Dependency Enumeration There are currently two ways to populate asset dependencies: * **Implied via AssetLoaders**: if an AssetLoader loads an asset (and retrieves a handle), a dependency is added to the list. * **Explicit via the optional Asset::visit_dependencies**: if `server.load_asset(my_asset)` is called, it will call `my_asset.visit_dependencies`, which will grab dependencies that have been manually defined for the asset via the Asset trait impl (which can be derived). This means that defining explicit dependencies is optional for "loaded assets". And the list of dependencies is always accurate because loaders can only produce Handles if they register dependencies. If an asset was loaded with an AssetLoader, it only uses the implied dependencies. If an asset was created at runtime and added with `asset_server.load_asset(MyAsset)`, it will use `Asset::visit_dependencies`. However this can create a behavior mismatch between loaded assets and equivalent "created at runtime" assets if `Assets::visit_dependencies` doesn't exactly match the dependencies produced by the AssetLoader. This behavior mismatch can be resolved by completely removing "implied loader dependencies" and requiring `Asset::visit_dependencies` to supply dependency data. But this creates two problems: * It makes defining loaded assets harder and more error prone: Devs must remember to manually annotate asset dependencies with `#[dependency]` when deriving `Asset`. For more complicated assets (such as scenes), the derive likely wouldn't be sufficient and a manual `visit_dependencies` impl would be required. * Removes the ability to immediately kick off dependency loads: When AssetLoaders retrieve a Handle, they also immediately kick off an asset load for the handle, which means it can start loading in parallel _before_ the asset finishes loading. For large assets, this could be significant. (although this could be mitigated for processed assets if we store dependencies in the processed meta file and load them ahead of time) ### Eager ProcessorDev Asset Loading I made a controversial call in the interest of fast startup times ("time to first pixel") for the "processor dev mode configuration". When initializing the AssetProcessor, current processed versions of unchanged assets are yielded immediately, even if their dependencies haven't been checked yet for reprocessing. This means that non-current-state-of-filesystem-but-previously-valid assets might be returned to the App first, then hot-reloaded if/when their dependencies change and the asset is reprocessed. Is this behavior desirable? There is largely one alternative: do not yield an asset from the processor to the app until all of its dependencies have been checked for changes. In some common cases (load dependency has not changed since last run) this will increase startup time. The main question is "by how much" and is that slower startup time worth it in the interest of only yielding assets that are true to the current state of the filesystem. Should this be configurable? I'm starting to think we should only yield an asset after its (historical) dependencies have been checked for changes + processed as necessary, but I'm curious what you all think. ### Paths Are Currently The Only Canonical ID / Do We Want Asset UUIDs? In this implementation AssetPaths are the only canonical asset identifier (just like the previous Bevy Asset system and Godot). Moving assets will result in re-scans (and currently reprocessing, although reprocessing can easily be avoided with some changes). Asset renames/moves will break code and assets that rely on specific paths, unless those paths are fixed up. Do we want / need "stable asset uuids"? Introducing them is very possible: 1. Generate a UUID and include it in .meta files 2. Support UUID in AssetPath 3. Generate "asset indices" which are loaded on startup and map UUIDs to paths. 4 (maybe). Consider only supporting UUIDs for processed assets so we can generate quick-to-load indices instead of scanning meta files. The main "pro" is that assets referencing UUIDs don't need to be migrated when a path changes. The main "con" is that UUIDs cannot be "lazily resolved" like paths. They need a full view of all assets to answer the question "does this UUID exist". Which means UUIDs require the AssetProcessor to fully finish startup scans before saying an asset doesnt exist. And they essentially require asset pre-processing to use in apps, because scanning all asset metadata files at runtime to resolve a UUID is not viable for medium-to-large apps. It really requires a pre-generated UUID index, which must be loaded before querying for assets. I personally think this should be investigated in a separate PR. Paths aren't going anywhere ... _everyone_ uses filesystems (and filesystem-like apis) to manage their asset source files. I consider them permanent canonical asset information. Additionally, they behave well for both processed and unprocessed asset modes. Given that Bevy is supporting both, this feels like the right canonical ID to start with. UUIDS (and maybe even other indexed-identifier types) can be added later as necessary. ### Folder / File Naming Conventions All asset processing config currently lives in the `.imported_assets` folder. The processor transaction log is in `.imported_assets/log`. Processed assets are added to `.imported_assets/Default`, which will make migrating to processed asset profiles (ex: a `.imported_assets/Mobile` profile) a non-breaking change. It also allows us to create top-level files like `.imported_assets/log` without it being interpreted as an asset. Meta files currently have a `.meta` suffix. Do we like these names and conventions? ### Should the `AssetPlugin::processed_dev` configuration enable `watch_for_changes` automatically? Currently it does (which I think makes sense), but it does make it the only configuration that enables watch_for_changes by default. ### Discuss on_loaded High Level Interface: This PR includes a very rough "proof of concept" `on_loaded` system adapter that uses the `LoadedWithDependencies` event in combination with `asset_server.load_asset` dependency tracking to support this pattern ```rust fn main() { App::new() .init_asset::<MyAssets>() .add_systems(Update, on_loaded(create_array_texture)) .run(); } #[derive(Asset, Clone)] struct MyAssets { #[dependency] picture_of_my_cat: Handle<Image>, #[dependency] picture_of_my_other_cat: Handle<Image>, } impl FromWorld for ArrayTexture { fn from_world(world: &mut World) -> Self { picture_of_my_cat: server.load("meow.png"), picture_of_my_other_cat: server.load("meeeeeeeow.png"), } } fn spawn_cat(In(my_assets): In<MyAssets>, mut commands: Commands) { commands.spawn(SpriteBundle { texture: my_assets.picture_of_my_cat.clone(), ..default() }); commands.spawn(SpriteBundle { texture: my_assets.picture_of_my_other_cat.clone(), ..default() }); } ``` The implementation is _very_ rough. And it is currently unsafe because `bevy_ecs` doesn't expose some internals to do this safely from inside `bevy_asset`. There are plenty of unanswered questions like: * "do we add a Loadable" derive? (effectively automate the FromWorld implementation above) * Should `MyAssets` even be an Asset? (largely implemented this way because it elegantly builds on `server.load_asset(MyAsset { .. })` dependency tracking). We should think hard about what our ideal API looks like (and if this is a pattern we want to support). Not necessarily something we need to solve in this PR. The current `on_loaded` impl should probably be removed from this PR before merging. ## Clarifying Questions ### What about Assets as Entities? This Bevy Asset V2 proposal implementation initially stored Assets as ECS Entities. Instead of `AssetId<T>` + the `Assets<T>` resource it used `Entity` as the asset id and Asset values were just ECS components. There are plenty of compelling reasons to do this: 1. Easier to inline assets in Bevy Scenes (as they are "just" normal entities + components) 2. More flexible queries: use the power of the ECS to filter assets (ex: `Query<Mesh, With<Tree>>`). 3. Extensible. Users can add arbitrary component data to assets. 4. Things like "component visualization tools" work out of the box to visualize asset data. However Assets as Entities has a ton of caveats right now: * We need to be able to allocate entity ids without a direct World reference (aka rework id allocator in Entities ... i worked around this in my prototypes by just pre allocating big chunks of entities) * We want asset change events in addition to ECS change tracking ... how do we populate them when mutations can come from anywhere? Do we use Changed queries? This would require iterating over the change data for all assets every frame. Is this acceptable or should we implement a new "event based" component change detection option? * Reconciling manually created assets with asset-system managed assets has some nuance (ex: are they "loaded" / do they also have that component metadata?) * "how do we handle "static" / default entity handles" (ties in to the Entity Indices discussion: https://github.com/bevyengine/bevy/discussions/8319). This is necessary for things like "built in" assets and default handles in things like SpriteBundle. * Storing asset information as a component makes it easy to "invalidate" asset state by removing the component (or forcing modifications). Ideally we have ways to lock this down (some combination of Rust type privacy and ECS validation) In practice, how we store and identify assets is a reasonably superficial change (porting off of Assets as Entities and implementing dedicated storage + ids took less than a day). So once we sort out the remaining challenges the flip should be straightforward. Additionally, I do still have "Assets as Entities" in my commit history, so we can reuse that work. I personally think "assets as entities" is a good endgame, but it also doesn't provide _significant_ value at the moment and it certainly isn't ready yet with the current state of things. ### Why not Distill? [Distill](https://github.com/amethyst/distill) is a high quality fully featured asset system built in Rust. It is very natural to ask "why not just use Distill?". It is also worth calling out that for awhile, [we planned on adopting Distill / I signed off on it](https://github.com/bevyengine/bevy/issues/708). However I think Bevy has a number of constraints that make Distill adoption suboptimal: * **Architectural Simplicity:** * Distill's processor requires an in-memory database (lmdb) and RPC networked API (using Cap'n Proto). Each of these introduces API complexity that increases maintenance burden and "code grokability". Ignoring tests, documentation, and examples, Distill has 24,237 lines of Rust code (including generated code for RPC + database interactions). If you ignore generated code, it has 11,499 lines. * Bevy builds the AssetProcessor and AssetServer using pluggable AssetReader/AssetWriter Rust traits with simple io interfaces. They do not necessitate databases or RPC interfaces (although Readers/Writers could use them if that is desired). Bevy Asset V2 (at the time of writing this PR) is 5,384 lines of Rust code (ignoring tests, documentation, and examples). Grain of salt: Distill does have more features currently (ex: Asset Packing, GUIDS, remote-out-of-process asset processor). I do plan to implement these features in Bevy Asset V2 and I personally highly doubt they will meaningfully close the 6115 lines-of-code gap. * This complexity gap (which while illustrated by lines of code, is much bigger than just that) is noteworthy to me. Bevy should be hackable and there are pillars of Distill that are very hard to understand and extend. This is a matter of opinion (and Bevy Asset V2 also has complicated areas), but I think Bevy Asset V2 is much more approachable for the average developer. * Necessary disclaimer: counting lines of code is an extremely rough complexity metric. Read the code and form your own opinions. * **Optional Asset Processing:** Not all Bevy Apps (or Bevy App developers) need / want asset preprocessing. Processing increases the complexity of the development environment by introducing things like meta files, imported asset storage, running processors in the background, waiting for processing to finish, etc. Distill _requires_ preprocessing to work. With Bevy Asset V2 processing is fully opt-in. The AssetServer isn't directly aware of asset processors at all. AssetLoaders only care about converting bytes to runtime Assets ... they don't know or care if the bytes were pre-processed or not. Processing is "elegantly" (forgive my self-congratulatory phrasing) layered on top and builds on the existing Asset system primitives. * **Direct Filesystem Access to Processed Asset State:** Distill stores processed assets in a database. This makes debugging / inspecting the processed outputs harder (either requires special tooling to query the database or they need to be "deployed" to be inspected). Bevy Asset V2, on the other hand, stores processed assets in the filesystem (by default ... this is configurable). This makes interacting with the processed state more natural. Note that both Godot and Unity's new asset system store processed assets in the filesystem. * **Portability**: Because Distill's processor uses lmdb and RPC networking, it cannot be run on certain platforms (ex: lmdb is a non-rust dependency that cannot run on the web, some platforms don't support running network servers). Bevy should be able to process assets everywhere (ex: run the Bevy Editor on the web, compile + process shaders on mobile, etc). Distill does partially mitigate this problem by supporting "streaming" assets via the RPC protocol, but this is not a full solve from my perspective. And Bevy Asset V2 can (in theory) also stream assets (without requiring RPC, although this isn't implemented yet) Note that I _do_ still think Distill would be a solid asset system for Bevy. But I think the approach in this PR is a better solve for Bevy's specific "asset system requirements". ### Doesn't async-fs just shim requests to "sync" `std::fs`? What is the point? "True async file io" has limited / spotty platform support. async-fs (and the rust async ecosystem generally ... ex Tokio) currently use async wrappers over std::fs that offload blocking requests to separate threads. This may feel unsatisfying, but it _does_ still provide value because it prevents our task pools from blocking on file system operations (which would prevent progress when there are many tasks to do, but all threads in a pool are currently blocking on file system ops). Additionally, using async APIs for our AssetReaders and AssetWriters also provides value because we can later add support for "true async file io" for platforms that support it. _And_ we can implement other "true async io" asset backends (such as networked asset io). ## Draft TODO - [x] Fill in missing filesystem event APIs: file removed event (which is expressed as dangling RenameFrom events in some cases), file/folder renamed event - [x] Assets without loaders are not moved to the processed folder. This breaks things like referenced `.bin` files for GLTFs. This should be configurable per-non-asset-type. - [x] Initial implementation of Reflect and FromReflect for Handle. The "deserialization" parity bar is low here as this only worked with static UUIDs in the old impl ... this is a non-trivial problem. Either we add a Handle::AssetPath variant that gets "upgraded" to a strong handle on scene load or we use a separate AssetRef type for Bevy scenes (which is converted to a runtime Handle on load). This deserves its own discussion in a different pr. - [x] Populate read_asset_bytes hash when run by the processor (a bit of a special case .. when run by the processor the processed meta will contain the hash so we don't need to compute it on the spot, but we don't want/need to read the meta when run by the main AssetServer) - [x] Delay hot reloading: currently filesystem events are handled immediately, which creates timing issues in some cases. For example hot reloading images can sometimes break because the image isn't finished writing. We should add a delay, likely similar to the [implementation in this PR](https://github.com/bevyengine/bevy/pull/8503). - [x] Port old platform-specific AssetIo implementations to the new AssetReader interface (currently missing Android and web) - [x] Resolve on_loaded unsafety (either by removing the API entirely or removing the unsafe) - [x] Runtime loader setting overrides - [x] Remove remaining unwraps that should be error-handled. There are number of TODOs here - [x] Pretty AssetPath Display impl - [x] Document more APIs - [x] Resolve spurious "reloading because it has changed" events (to repro run load_gltf with `processed_dev()`) - [x] load_dependency hot reloading currently only works for processed assets. If processing is disabled, load_dependency changes are not hot reloaded. - [x] Replace AssetInfo dependency load/fail counters with `loading_dependencies: HashSet<UntypedAssetId>` to prevent reloads from (potentially) breaking counters. Storing this will also enable "dependency reloaded" events (see [Next Steps](#next-steps)) - [x] Re-add filesystem watcher cargo feature gate (currently it is not optional) - [ ] Migration Guide - [ ] Changelog ## Followup TODO - [ ] Replace "eager unchanged processed asset loading" behavior with "don't returned unchanged processed asset until dependencies have been checked". - [ ] Add true `Ignore` AssetAction that does not copy the asset to the imported_assets folder. - [ ] Finish "live asset unloading" (ex: free up CPU asset memory after uploading an image to the GPU), rethink RenderAssets, and port renderer features. The `Assets` collection uses `Option<T>` for asset storage to support its removal. (1) the Option might not actually be necessary ... might be able to just remove from the collection entirely (2) need to finalize removal apis - [ ] Try replacing the "channel based" asset id recycling with something a bit more efficient (ex: we might be able to use raw atomic ints with some cleverness) - [ ] Consider adding UUIDs to processed assets (scoped just to helping identify moved assets ... not exposed to load queries ... see [Next Steps](#next-steps)) - [ ] Store "last modified" source asset and meta timestamps in processed meta files to enable skipping expensive hashing when the file wasn't changed - [ ] Fix "slow loop" handle drop fix - [ ] Migrate to TypeName - [x] Handle "loader preregistration". See #9429 ## Next Steps * **Configurable per-type defaults for AssetMeta**: It should be possible to add configuration like "all png image meta should default to using nearest sampling" (currently this hard-coded per-loader/processor Settings::default() impls). Also see the "Folder Meta" bullet point. * **Avoid Reprocessing on Asset Renames / Moves**: See the "canonical asset ids" discussion in [Open Questions](#open-questions) and the relevant bullet point in [Draft TODO](#draft-todo). Even without canonical ids, folder renames could avoid reprocessing in some cases. * **Multiple Asset Sources**: Expand AssetPath to support "asset source names" and support multiple AssetReaders in the asset server (ex: `webserver://some_path/image.png` backed by an Http webserver AssetReader). The "default" asset reader would use normal `some_path/image.png` paths. Ideally this works in combination with multiple AssetWatchers for hot-reloading * **Stable Type Names**: this pr removes the TypeUuid requirement from assets in favor of `std::any::type_name`. This makes defining assets easier (no need to generate a new uuid / use weird proc macro syntax). It also makes reading meta files easier (because things have "friendly names"). We also use type names for components in scene files. If they are good enough for components, they are good enough for assets. And consistency across Bevy pillars is desirable. However, `std::any::type_name` is not guaranteed to be stable (although in practice it is). We've developed a [stable type path](https://github.com/bevyengine/bevy/pull/7184) to resolve this, which should be adopted when it is ready. * **Command Line Interface**: It should be possible to run the asset processor in a separate process from the command line. This will also require building a network-server-backed AssetReader to communicate between the app and the processor. We've been planning to build a "bevy cli" for awhile. This seems like a good excuse to build it. * **Asset Packing**: This is largely an additive feature, so it made sense to me to punt this until we've laid the foundations in this PR. * **Per-Platform Processed Assets**: It should be possible to generate assets for multiple platforms by supporting multiple "processor profiles" per asset (ex: compress with format X on PC and Y on iOS). I think there should probably be arbitrary "profiles" (which can be separate from actual platforms), which are then assigned to a given platform when generating the final asset distribution for that platform. Ex: maybe devs want a "Mobile" profile that is shared between iOS and Android. Or a "LowEnd" profile shared between web and mobile. * **Versioning and Migrations**: Assets, Loaders, Savers, and Processors need to have versions to determine if their schema is valid. If an asset / loader version is incompatible with the current version expected at runtime, the processor should be able to migrate them. I think we should try using Bevy Reflect for this, as it would allow us to load the old version as a dynamic Reflect type without actually having the old Rust type. It would also allow us to define "patches" to migrate between versions (Bevy Reflect devs are currently working on patching). The `.meta` file already has its own format version. Migrating that to new versions should also be possible. * **Real Copy-on-write AssetPaths**: Rust's actual Cow (clone-on-write type) currently used by AssetPath can still result in String clones that aren't actually necessary (cloning an Owned Cow clones the contents). Bevy's asset system requires cloning AssetPaths in a number of places, which result in actual clones of the internal Strings. This is not efficient. AssetPath internals should be reworked to exhibit truer cow-like-behavior that reduces String clones to the absolute minimum. * **Consider processor-less processing**: In theory the AssetServer could run processors "inline" even if the background AssetProcessor is disabled. If we decide this is actually desirable, we could add this. But I don't think its a priority in the short or medium term. * **Pre-emptive dependency loading**: We could encode dependencies in processed meta files, which could then be used by the Asset Server to kick of dependency loads as early as possible (prior to starting the actual asset load). Is this desirable? How much time would this save in practice? * **Optimize Processor With UntypedAssetIds**: The processor exclusively uses AssetPath to identify assets currently. It might be possible to swap these out for UntypedAssetIds in some places, which are smaller / cheaper to hash and compare. * **One to Many Asset Processing**: An asset source file that produces many assets currently must be processed into a single "processed" asset source. If labeled assets can be written separately they can each have their own configured savers _and_ they could be loaded more granularly. Definitely worth exploring! * **Automatically Track "Runtime-only" Asset Dependencies**: Right now, tracking "created at runtime" asset dependencies requires adding them via `asset_server.load_asset(StandardMaterial::default())`. I think with some cleverness we could also do this for `materials.add(StandardMaterial::default())`, making tracking work "everywhere". There are challenges here relating to change detection / ensuring the server is made aware of dependency changes. This could be expensive in some cases. * **"Dependency Changed" events**: Some assets have runtime artifacts that need to be re-generated when one of their dependencies change (ex: regenerate a material's bind group when a Texture needs to change). We are generating the dependency graph so we can definitely produce these events. Buuuuut generating these events will have a cost / they could be high frequency for some assets, so we might want this to be opt-in for specific cases. * **Investigate Storing More Information In Handles**: Handles can now store arbitrary information, which makes it cheaper and easier to access. How much should we move into them? Canonical asset load states (via atomics)? (`handle.is_loaded()` would be very cool). Should we store the entire asset and remove the `Assets<T>` collection? (`Arc<RwLock<Option<Image>>>`?) * **Support processing and loading files without extensions**: This is a pretty arbitrary restriction and could be supported with very minimal changes. * **Folder Meta**: It would be nice if we could define per folder processor configuration defaults (likely in a `.meta` or `.folder_meta` file). Things like "default to linear filtering for all Images in this folder". * **Replace async_broadcast with event-listener?** This might be approximately drop-in for some uses and it feels more light weight * **Support Running the AssetProcessor on the Web**: Most of the hard work is done here, but there are some easy straggling TODOs (make the transaction log an interface instead of a direct file writer so we can write a web storage backend, implement an AssetReader/AssetWriter that reads/writes to something like LocalStorage). * **Consider identifying and preventing circular dependencies**: This is especially important for "processor dependencies", as processing will silently never finish in these cases. * **Built-in/Inlined Asset Hot Reloading**: This PR regresses "built-in/inlined" asset hot reloading (previously provided by the DebugAssetServer). I'm intentionally punting this because I think it can be cleanly implemented with "multiple asset sources" by registering a "debug asset source" (ex: `debug://bevy_pbr/src/render/pbr.wgsl` asset paths) in combination with an AssetWatcher for that asset source and support for "manually loading pats with asset bytes instead of AssetReaders". The old DebugAssetServer was quite nasty and I'd love to avoid that hackery going forward. * **Investigate ways to remove double-parsing meta files**: Parsing meta files currently involves parsing once with "minimal" versions of the meta file to extract the type name of the loader/processor config, then parsing again to parse the "full" meta. This is suboptimal. We should be able to define custom deserializers that (1) assume the loader/processor type name comes first (2) dynamically looks up the loader/processor registrations to deserialize settings in-line (similar to components in the bevy scene format). Another alternative: deserialize as dynamic Reflect objects and then convert. * **More runtime loading configuration**: Support using the Handle type as a hint to select an asset loader (instead of relying on AssetPath extensions) * **More high level Processor trait implementations**: For example, it might be worth adding support for arbitrary chains of "asset transforms" that modify an in-memory asset representation between loading and saving. (ex: load a Mesh, run a `subdivide_mesh` transform, followed by a `flip_normals` transform, then save the mesh to an efficient compressed format). * **Bevy Scene Handle Deserialization**: (see the relevant [Draft TODO item](#draft-todo) for context) * **Explore High Level Load Interfaces**: See [this discussion](#discuss-on_loaded-high-level-interface) for one prototype. * **Asset Streaming**: It would be great if we could stream Assets (ex: stream a long video file piece by piece) * **ID Exchanging**: In this PR Asset Handles/AssetIds are bigger than they need to be because they have a Uuid enum variant. If we implement an "id exchanging" system that trades Uuids for "efficient runtime ids", we can cut down on the size of AssetIds, making them more efficient. This has some open design questions, such as how to spawn entities with "default" handle values (as these wouldn't have access to the exchange api in the current system). * **Asset Path Fixup Tooling**: Assets that inline asset paths inside them will break when an asset moves. The asset system provides the functionality to detect when paths break. We should build a framework that enables formats to define "path migrations". This is especially important for scene files. For editor-generated files, we should also consider using UUIDs (see other bullet point) to avoid the need to migrate in these cases. --------- Co-authored-by: BeastLe9enD <beastle9end@outlook.de> Co-authored-by: Mike <mike.hsu@gmail.com> Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com>
2023-09-07 02:07:27 +00:00
2019-11-13 03:36:02 +00:00
[dependencies]
bevy_dylib = { path = "crates/bevy_dylib", version = "0.12.0", default-features = false, optional = true }
bevy_internal = { path = "crates/bevy_internal", version = "0.12.0", default-features = false }
2020-04-06 03:19:02 +00:00
[dev-dependencies]
rand = "0.8.0"
ron = "0.8.0"
serde = { version = "1", features = ["derive"] }
bytemuck = "1.7"
# Needed to poll Task examples
futures-lite = "1.11.3"
crossbeam-channel = "0.5.0"
argh = "0.1.12"
2020-05-01 20:12:47 +00:00
[[example]]
name = "hello_world"
path = "examples/hello_world.rs"
doc-scrape-examples = true
2020-05-01 20:12:47 +00:00
[package.metadata.example.hello_world]
hidden = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
# 2D Rendering
Revamp Bloom (#6677) ![image](https://user-images.githubusercontent.com/47158642/220197588-25e11022-02e4-45f3-b2e5-392c4ce7a025.png) Huge credit to @StarLederer, who did almost all of the work on this. We're just reusing this PR to keep everything in one place. # Objective 1. Make bloom more physically based. 1. Improve artistic control. 1. Allow to use bloom as screen blur. 1. Fix #6634. 1. Address #6655 (although the author makes incorrect conclusions). ## Solution 1. Set the default threshold to 0. 2. Lerp between bloom textures when `composite_mode: BloomCompositeMode::EnergyConserving`. 1. Use [a parametric function](https://starlederer.github.io/bloom) to control blend levels for each bloom texture. In the future this can be controlled per-pixel for things like lens dirt. 3. Implement BloomCompositeMode::Additive` for situations where the old school look is desired. ## Changelog * Bloom now looks different. * Added `BloomSettings:lf_boost`, `BloomSettings:lf_boost_curvature`, `BloomSettings::high_pass_frequency` and `BloomSettings::composite_mode`. * `BloomSettings::scale` removed. * `BloomSettings::knee` renamed to `BloomPrefilterSettings::softness`. * `BloomSettings::threshold` renamed to `BloomPrefilterSettings::threshold`. * The bloom example has been renamed to bloom_3d and improved. A bloom_2d example was added. ## Migration Guide * Refactor mentions of `BloomSettings::knee` and `BloomSettings::threshold` as `BloomSettings::prefilter_settings` where knee is now `softness`. * If defined without `..default()` add `..default()` to definitions of `BloomSettings` instances or manually define missing fields. * Adapt to Bloom looking visually different (if needed). Co-authored-by: Herman Lederer <germans.lederers@gmail.com>
2023-03-04 12:05:26 +00:00
[[example]]
name = "bloom_2d"
path = "examples/2d/bloom_2d.rs"
doc-scrape-examples = true
Revamp Bloom (#6677) ![image](https://user-images.githubusercontent.com/47158642/220197588-25e11022-02e4-45f3-b2e5-392c4ce7a025.png) Huge credit to @StarLederer, who did almost all of the work on this. We're just reusing this PR to keep everything in one place. # Objective 1. Make bloom more physically based. 1. Improve artistic control. 1. Allow to use bloom as screen blur. 1. Fix #6634. 1. Address #6655 (although the author makes incorrect conclusions). ## Solution 1. Set the default threshold to 0. 2. Lerp between bloom textures when `composite_mode: BloomCompositeMode::EnergyConserving`. 1. Use [a parametric function](https://starlederer.github.io/bloom) to control blend levels for each bloom texture. In the future this can be controlled per-pixel for things like lens dirt. 3. Implement BloomCompositeMode::Additive` for situations where the old school look is desired. ## Changelog * Bloom now looks different. * Added `BloomSettings:lf_boost`, `BloomSettings:lf_boost_curvature`, `BloomSettings::high_pass_frequency` and `BloomSettings::composite_mode`. * `BloomSettings::scale` removed. * `BloomSettings::knee` renamed to `BloomPrefilterSettings::softness`. * `BloomSettings::threshold` renamed to `BloomPrefilterSettings::threshold`. * The bloom example has been renamed to bloom_3d and improved. A bloom_2d example was added. ## Migration Guide * Refactor mentions of `BloomSettings::knee` and `BloomSettings::threshold` as `BloomSettings::prefilter_settings` where knee is now `softness`. * If defined without `..default()` add `..default()` to definitions of `BloomSettings` instances or manually define missing fields. * Adapt to Bloom looking visually different (if needed). Co-authored-by: Herman Lederer <germans.lederers@gmail.com>
2023-03-04 12:05:26 +00:00
[package.metadata.example.bloom_2d]
name = "2D Bloom"
description = "Illustrates bloom post-processing in 2d"
category = "2D Rendering"
wasm = true
Revamp Bloom (#6677) ![image](https://user-images.githubusercontent.com/47158642/220197588-25e11022-02e4-45f3-b2e5-392c4ce7a025.png) Huge credit to @StarLederer, who did almost all of the work on this. We're just reusing this PR to keep everything in one place. # Objective 1. Make bloom more physically based. 1. Improve artistic control. 1. Allow to use bloom as screen blur. 1. Fix #6634. 1. Address #6655 (although the author makes incorrect conclusions). ## Solution 1. Set the default threshold to 0. 2. Lerp between bloom textures when `composite_mode: BloomCompositeMode::EnergyConserving`. 1. Use [a parametric function](https://starlederer.github.io/bloom) to control blend levels for each bloom texture. In the future this can be controlled per-pixel for things like lens dirt. 3. Implement BloomCompositeMode::Additive` for situations where the old school look is desired. ## Changelog * Bloom now looks different. * Added `BloomSettings:lf_boost`, `BloomSettings:lf_boost_curvature`, `BloomSettings::high_pass_frequency` and `BloomSettings::composite_mode`. * `BloomSettings::scale` removed. * `BloomSettings::knee` renamed to `BloomPrefilterSettings::softness`. * `BloomSettings::threshold` renamed to `BloomPrefilterSettings::threshold`. * The bloom example has been renamed to bloom_3d and improved. A bloom_2d example was added. ## Migration Guide * Refactor mentions of `BloomSettings::knee` and `BloomSettings::threshold` as `BloomSettings::prefilter_settings` where knee is now `softness`. * If defined without `..default()` add `..default()` to definitions of `BloomSettings` instances or manually define missing fields. * Adapt to Bloom looking visually different (if needed). Co-authored-by: Herman Lederer <germans.lederers@gmail.com>
2023-03-04 12:05:26 +00:00
[[example]]
name = "move_sprite"
path = "examples/2d/move_sprite.rs"
doc-scrape-examples = true
[package.metadata.example.move_sprite]
name = "Move Sprite"
description = "Changes the transform of a sprite"
category = "2D Rendering"
wasm = true
[[example]]
name = "2d_viewport_to_world"
path = "examples/2d/2d_viewport_to_world.rs"
[package.metadata.example.2d_viewport_to_world]
name = "2D Viewport To World"
description = "Demonstrates how to use the `Camera::viewport_to_world_2d` method"
category = "2D Rendering"
wasm = true
[[example]]
name = "rotation"
path = "examples/2d/rotation.rs"
doc-scrape-examples = true
[package.metadata.example.rotation]
name = "2D Rotation"
description = "Demonstrates rotating entities in 2D with quaternions"
category = "2D Rendering"
wasm = true
[[example]]
name = "mesh2d"
path = "examples/2d/mesh2d.rs"
doc-scrape-examples = true
[package.metadata.example.mesh2d]
name = "Mesh 2D"
description = "Renders a 2d mesh"
category = "2D Rendering"
wasm = true
[[example]]
name = "mesh2d_manual"
path = "examples/2d/mesh2d_manual.rs"
doc-scrape-examples = true
[package.metadata.example.mesh2d_manual]
name = "Manual Mesh 2D"
description = "Renders a custom mesh \"manually\" with \"mid-level\" renderer apis"
category = "2D Rendering"
wasm = true
[[example]]
name = "mesh2d_vertex_color_texture"
path = "examples/2d/mesh2d_vertex_color_texture.rs"
doc-scrape-examples = true
[package.metadata.example.mesh2d_vertex_color_texture]
name = "Mesh 2D With Vertex Colors"
description = "Renders a 2d mesh with vertex color attributes"
category = "2D Rendering"
wasm = true
Add an example to draw a rectangle (#2957) # Objective Every time I come back to Bevy I face the same issue: how do I draw a rectangle again? How did that work? So I go to https://github.com/bevyengine/bevy/tree/main/examples in the hope of finding literally the simplest possible example that draws something on the screen without any dependency such as an image. I don't want to have to add some image first, I just quickly want to get something on the screen with `main.rs` alone so that I can continue building on from that point on. Such an example is particularly helpful for a quick start for smaller projects that don't even need any assets such as images (this is my case currently). Currently every single example of https://github.com/bevyengine/bevy/tree/main/examples#2d-rendering (which is the first section after hello world that beginners will look for for very minimalistic and quick examples) depends on at least an asset or is too complex. This PR solves this. It also serves as a great comparison for a beginner to realize what Bevy is really like and how different it is from what they may expect Bevy to be. For example for someone coming from [LÖVE](https://love2d.org/), they will have something like this in their head when they think of drawing a rectangle: ```lua function love.draw() love.graphics.setColor(0.25, 0.25, 0.75); love.graphics.rectangle("fill", 0, 0, 50, 50); end ``` This, of course, differs quite a lot from what you do in Bevy. I imagine there will be people that just want to see something as simple as this in comparison to have a better understanding for the amount of differences. ## Solution Add a dead simple example drawing a blue 50x50 rectangle in the center with no more and no less than needed.
2021-12-18 00:52:37 +00:00
[[example]]
name = "2d_shapes"
path = "examples/2d/2d_shapes.rs"
doc-scrape-examples = true
Add an example to draw a rectangle (#2957) # Objective Every time I come back to Bevy I face the same issue: how do I draw a rectangle again? How did that work? So I go to https://github.com/bevyengine/bevy/tree/main/examples in the hope of finding literally the simplest possible example that draws something on the screen without any dependency such as an image. I don't want to have to add some image first, I just quickly want to get something on the screen with `main.rs` alone so that I can continue building on from that point on. Such an example is particularly helpful for a quick start for smaller projects that don't even need any assets such as images (this is my case currently). Currently every single example of https://github.com/bevyengine/bevy/tree/main/examples#2d-rendering (which is the first section after hello world that beginners will look for for very minimalistic and quick examples) depends on at least an asset or is too complex. This PR solves this. It also serves as a great comparison for a beginner to realize what Bevy is really like and how different it is from what they may expect Bevy to be. For example for someone coming from [LÖVE](https://love2d.org/), they will have something like this in their head when they think of drawing a rectangle: ```lua function love.draw() love.graphics.setColor(0.25, 0.25, 0.75); love.graphics.rectangle("fill", 0, 0, 50, 50); end ``` This, of course, differs quite a lot from what you do in Bevy. I imagine there will be people that just want to see something as simple as this in comparison to have a better understanding for the amount of differences. ## Solution Add a dead simple example drawing a blue 50x50 rectangle in the center with no more and no less than needed.
2021-12-18 00:52:37 +00:00
[package.metadata.example.2d_shapes]
name = "2D Shapes"
description = "Renders a rectangle, circle, and hexagon"
category = "2D Rendering"
wasm = true
[[example]]
name = "custom_gltf_vertex_attribute"
path = "examples/2d/custom_gltf_vertex_attribute.rs"
doc-scrape-examples = true
[package.metadata.example.custom_gltf_vertex_attribute]
name = "Custom glTF vertex attribute 2D"
description = "Renders a glTF mesh in 2D with a custom vertex attribute"
category = "2D Rendering"
wasm = true
Immediate Mode Line/Gizmo Drawing (#6529) # Objective Add a convenient immediate mode drawing API for visual debugging. Fixes #5619 Alternative to #1625 Partial alternative to #5734 Based off https://github.com/Toqozz/bevy_debug_lines with some changes: * Simultaneous support for 2D and 3D. * Methods for basic shapes; circles, spheres, rectangles, boxes, etc. * 2D methods. * Removed durations. Seemed niche, and can be handled by users. <details> <summary>Performance</summary> Stress tested using Bevy's recommended optimization settings for the dev profile with the following command. ```bash cargo run --example many_debug_lines \ --config "profile.dev.package.\"*\".opt-level=3" \ --config "profile.dev.opt-level=1" ``` I dipped to 65-70 FPS at 300,000 lines CPU: 3700x RAM Speed: 3200 Mhz GPU: 2070 super - probably not very relevant, mostly cpu/memory bound </details> <details> <summary>Fancy bloom screenshot</summary> ![Screenshot_20230207_155033](https://user-images.githubusercontent.com/29694403/217291980-f1e0500e-7a14-4131-8c96-eaaaf52596ae.png) </details> ## Changelog * Added `GizmoPlugin` * Added `Gizmos` system parameter for drawing lines and wireshapes. ### TODO - [ ] Update changelog - [x] Update performance numbers - [x] Add credit to PR description ### Future work - Cache rendering primitives instead of constructing them out of line segments each frame. - Support for drawing solid meshes - Interactions. (See [bevy_mod_gizmos](https://github.com/LiamGallagher737/bevy_mod_gizmos)) - Fancier line drawing. (See [bevy_polyline](https://github.com/ForesightMiningSoftwareCorporation/bevy_polyline)) - Support for `RenderLayers` - Display gizmos for a certain duration. Currently everything displays for one frame (ie. immediate mode) - Changing settings per drawn item like drawing on top or drawing to different `RenderLayers` Co-Authored By: @lassade <felipe.jorge.pereira@gmail.com> Co-Authored By: @The5-1 <agaku@hotmail.de> Co-Authored By: @Toqozz <toqoz@hotmail.com> Co-Authored By: @nicopap <nico@nicopap.ch> --------- Co-authored-by: Robert Swain <robert.swain@gmail.com> Co-authored-by: IceSentry <c.giguere42@gmail.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2023-03-20 20:57:54 +00:00
[[example]]
name = "2d_gizmos"
path = "examples/2d/2d_gizmos.rs"
doc-scrape-examples = true
Immediate Mode Line/Gizmo Drawing (#6529) # Objective Add a convenient immediate mode drawing API for visual debugging. Fixes #5619 Alternative to #1625 Partial alternative to #5734 Based off https://github.com/Toqozz/bevy_debug_lines with some changes: * Simultaneous support for 2D and 3D. * Methods for basic shapes; circles, spheres, rectangles, boxes, etc. * 2D methods. * Removed durations. Seemed niche, and can be handled by users. <details> <summary>Performance</summary> Stress tested using Bevy's recommended optimization settings for the dev profile with the following command. ```bash cargo run --example many_debug_lines \ --config "profile.dev.package.\"*\".opt-level=3" \ --config "profile.dev.opt-level=1" ``` I dipped to 65-70 FPS at 300,000 lines CPU: 3700x RAM Speed: 3200 Mhz GPU: 2070 super - probably not very relevant, mostly cpu/memory bound </details> <details> <summary>Fancy bloom screenshot</summary> ![Screenshot_20230207_155033](https://user-images.githubusercontent.com/29694403/217291980-f1e0500e-7a14-4131-8c96-eaaaf52596ae.png) </details> ## Changelog * Added `GizmoPlugin` * Added `Gizmos` system parameter for drawing lines and wireshapes. ### TODO - [ ] Update changelog - [x] Update performance numbers - [x] Add credit to PR description ### Future work - Cache rendering primitives instead of constructing them out of line segments each frame. - Support for drawing solid meshes - Interactions. (See [bevy_mod_gizmos](https://github.com/LiamGallagher737/bevy_mod_gizmos)) - Fancier line drawing. (See [bevy_polyline](https://github.com/ForesightMiningSoftwareCorporation/bevy_polyline)) - Support for `RenderLayers` - Display gizmos for a certain duration. Currently everything displays for one frame (ie. immediate mode) - Changing settings per drawn item like drawing on top or drawing to different `RenderLayers` Co-Authored By: @lassade <felipe.jorge.pereira@gmail.com> Co-Authored By: @The5-1 <agaku@hotmail.de> Co-Authored By: @Toqozz <toqoz@hotmail.com> Co-Authored By: @nicopap <nico@nicopap.ch> --------- Co-authored-by: Robert Swain <robert.swain@gmail.com> Co-authored-by: IceSentry <c.giguere42@gmail.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2023-03-20 20:57:54 +00:00
[package.metadata.example.2d_gizmos]
name = "2D Gizmos"
description = "A scene showcasing 2D gizmos"
category = "2D Rendering"
wasm = true
2020-05-04 08:22:25 +00:00
[[example]]
name = "sprite"
path = "examples/2d/sprite.rs"
doc-scrape-examples = true
2020-05-04 08:22:25 +00:00
[package.metadata.example.sprite]
name = "Sprite"
description = "Renders a sprite"
category = "2D Rendering"
wasm = true
Add Sprite Flipping (#1407) OK, here's my attempt at sprite flipping. There are a couple of points that I need review/help on, but I think the UX is about ideal: ```rust .spawn(SpriteBundle { material: materials.add(texture_handle.into()), sprite: Sprite { // Flip the sprite along the x axis flip: SpriteFlip { x: true, y: false }, ..Default::default() }, ..Default::default() }); ``` Now for the issues. The big issue is that for some reason, when flipping the UVs on the sprite, there is a light "bleeding" or whatever you call it where the UV tries to sample past the texture boundry and ends up clipping. This is only noticed when resizing the window, though. You can see a screenshot below. ![image](https://user-images.githubusercontent.com/25393315/107098172-397aaa00-67d4-11eb-8e02-c90c820cd70e.png) I am quite baffled why the texture sampling is overrunning like it is and could use some guidance if anybody knows what might be wrong. The other issue, which I just worked around, is that I had to remove the `#[render_resources(from_self)]` annotation from the Spritesheet because the `SpriteFlip` render resource wasn't being picked up properly in the shader when using it. I'm not sure what the cause of that was, but by removing the annotation and re-organizing the shader inputs accordingly the problem was fixed. I'm not sure if this is the most efficient way to do this or if there is a better way, but I wanted to try it out if only for the learning experience. Let me know what you think!
2021-03-03 19:26:45 +00:00
[[example]]
name = "sprite_flipping"
path = "examples/2d/sprite_flipping.rs"
doc-scrape-examples = true
Add Sprite Flipping (#1407) OK, here's my attempt at sprite flipping. There are a couple of points that I need review/help on, but I think the UX is about ideal: ```rust .spawn(SpriteBundle { material: materials.add(texture_handle.into()), sprite: Sprite { // Flip the sprite along the x axis flip: SpriteFlip { x: true, y: false }, ..Default::default() }, ..Default::default() }); ``` Now for the issues. The big issue is that for some reason, when flipping the UVs on the sprite, there is a light "bleeding" or whatever you call it where the UV tries to sample past the texture boundry and ends up clipping. This is only noticed when resizing the window, though. You can see a screenshot below. ![image](https://user-images.githubusercontent.com/25393315/107098172-397aaa00-67d4-11eb-8e02-c90c820cd70e.png) I am quite baffled why the texture sampling is overrunning like it is and could use some guidance if anybody knows what might be wrong. The other issue, which I just worked around, is that I had to remove the `#[render_resources(from_self)]` annotation from the Spritesheet because the `SpriteFlip` render resource wasn't being picked up properly in the shader when using it. I'm not sure what the cause of that was, but by removing the annotation and re-organizing the shader inputs accordingly the problem was fixed. I'm not sure if this is the most efficient way to do this or if there is a better way, but I wanted to try it out if only for the learning experience. Let me know what you think!
2021-03-03 19:26:45 +00:00
[package.metadata.example.sprite_flipping]
name = "Sprite Flipping"
description = "Renders a sprite flipped along an axis"
category = "2D Rendering"
wasm = true
[[example]]
name = "sprite_sheet"
path = "examples/2d/sprite_sheet.rs"
doc-scrape-examples = true
[package.metadata.example.sprite_sheet]
name = "Sprite Sheet"
description = "Renders an animated sprite"
category = "2D Rendering"
wasm = true
[[example]]
name = "text2d"
path = "examples/2d/text2d.rs"
doc-scrape-examples = true
[package.metadata.example.text2d]
name = "Text 2D"
description = "Generates text in 2D"
category = "2D Rendering"
wasm = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[[example]]
name = "texture_atlas"
path = "examples/2d/texture_atlas.rs"
doc-scrape-examples = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[package.metadata.example.texture_atlas]
name = "Texture Atlas"
description = "Generates a texture atlas (sprite sheet) from individual sprites"
category = "2D Rendering"
wasm = false
[[example]]
name = "transparency_2d"
path = "examples/2d/transparency_2d.rs"
doc-scrape-examples = true
[package.metadata.example.transparency_2d]
name = "Transparency in 2D"
description = "Demonstrates transparency in 2d"
category = "2D Rendering"
wasm = true
[[example]]
name = "pixel_perfect"
path = "examples/2d/pixel_perfect.rs"
doc-scrape-examples = true
[package.metadata.example.pixel_perfect]
name = "Pixel Perfect"
description = "Demonstrates pixel perfect in 2d"
category = "2D Rendering"
wasm = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
# 3D Rendering
[[example]]
name = "3d_scene"
path = "examples/3d/3d_scene.rs"
doc-scrape-examples = true
[package.metadata.example.3d_scene]
name = "3D Scene"
description = "Simple 3D scene with basic shapes and lighting"
category = "3D Rendering"
wasm = true
Camera Driven Viewports (#4898) # Objective Users should be able to render cameras to specific areas of a render target, which enables scenarios like split screen, minimaps, etc. Builds on the new Camera Driven Rendering added here: #4745 Fixes: #202 Alternative to #1389 and #3626 (which are incompatible with the new Camera Driven Rendering) ## Solution ![image](https://user-images.githubusercontent.com/2694663/171560044-f0694f67-0cd9-4598-83e2-a9658c4fed57.png) Cameras can now configure an optional "viewport", which defines a rectangle within their render target to draw to. If a `Viewport` is defined, the camera's `CameraProjection`, `View`, and visibility calculations will use the viewport configuration instead of the full render target. ```rust // This camera will render to the first half of the primary window (on the left side). commands.spawn_bundle(Camera3dBundle { camera: Camera { viewport: Some(Viewport { physical_position: UVec2::new(0, 0), physical_size: UVec2::new(window.physical_width() / 2, window.physical_height()), depth: 0.0..1.0, }), ..default() }, ..default() }); ``` To account for this, the `Camera` component has received a few adjustments: * `Camera` now has some new getter functions: * `logical_viewport_size`, `physical_viewport_size`, `logical_target_size`, `physical_target_size`, `projection_matrix` * All computed camera values are now private and live on the `ComputedCameraValues` field (logical/physical width/height, the projection matrix). They are now exposed on `Camera` via getters/setters This wasn't _needed_ for viewports, but it was long overdue. --- ## Changelog ### Added * `Camera` components now have a `viewport` field, which can be set to draw to a portion of a render target instead of the full target. * `Camera` component has some new functions: `logical_viewport_size`, `physical_viewport_size`, `logical_target_size`, `physical_target_size`, and `projection_matrix` * Added a new split_screen example illustrating how to render two cameras to the same scene ## Migration Guide `Camera::projection_matrix` is no longer a public field. Use the new `Camera::projection_matrix()` method instead: ```rust // Bevy 0.7 let projection = camera.projection_matrix; // Bevy 0.8 let projection = camera.projection_matrix(); ```
2022-06-05 00:27:49 +00:00
[[example]]
name = "3d_shapes"
path = "examples/3d/3d_shapes.rs"
doc-scrape-examples = true
Camera Driven Viewports (#4898) # Objective Users should be able to render cameras to specific areas of a render target, which enables scenarios like split screen, minimaps, etc. Builds on the new Camera Driven Rendering added here: #4745 Fixes: #202 Alternative to #1389 and #3626 (which are incompatible with the new Camera Driven Rendering) ## Solution ![image](https://user-images.githubusercontent.com/2694663/171560044-f0694f67-0cd9-4598-83e2-a9658c4fed57.png) Cameras can now configure an optional "viewport", which defines a rectangle within their render target to draw to. If a `Viewport` is defined, the camera's `CameraProjection`, `View`, and visibility calculations will use the viewport configuration instead of the full render target. ```rust // This camera will render to the first half of the primary window (on the left side). commands.spawn_bundle(Camera3dBundle { camera: Camera { viewport: Some(Viewport { physical_position: UVec2::new(0, 0), physical_size: UVec2::new(window.physical_width() / 2, window.physical_height()), depth: 0.0..1.0, }), ..default() }, ..default() }); ``` To account for this, the `Camera` component has received a few adjustments: * `Camera` now has some new getter functions: * `logical_viewport_size`, `physical_viewport_size`, `logical_target_size`, `physical_target_size`, `projection_matrix` * All computed camera values are now private and live on the `ComputedCameraValues` field (logical/physical width/height, the projection matrix). They are now exposed on `Camera` via getters/setters This wasn't _needed_ for viewports, but it was long overdue. --- ## Changelog ### Added * `Camera` components now have a `viewport` field, which can be set to draw to a portion of a render target instead of the full target. * `Camera` component has some new functions: `logical_viewport_size`, `physical_viewport_size`, `logical_target_size`, `physical_target_size`, and `projection_matrix` * Added a new split_screen example illustrating how to render two cameras to the same scene ## Migration Guide `Camera::projection_matrix` is no longer a public field. Use the new `Camera::projection_matrix()` method instead: ```rust // Bevy 0.7 let projection = camera.projection_matrix; // Bevy 0.8 let projection = camera.projection_matrix(); ```
2022-06-05 00:27:49 +00:00
[package.metadata.example.3d_shapes]
name = "3D Shapes"
description = "A scene showcasing the built-in 3D shapes"
category = "3D Rendering"
wasm = true
[[example]]
name = "3d_viewport_to_world"
path = "examples/3d/3d_viewport_to_world.rs"
doc-scrape-examples = true
[package.metadata.example.3d_viewport_to_world]
name = "3D Viewport To World"
description = "Demonstrates how to use the `Camera::viewport_to_world` method"
category = "3D Rendering"
wasm = true
[[example]]
name = "generate_custom_mesh"
path = "examples/3d/generate_custom_mesh.rs"
doc-scrape-examples = true
[package.metadata.example.generate_custom_mesh]
name = "Generate Custom Mesh"
description = "Simple showcase of how to generate a custom mesh with a custom texture"
category = "3D Rendering"
wasm = true
Temporal Antialiasing (TAA) (#7291) ![image](https://user-images.githubusercontent.com/47158642/214374911-412f0986-3927-4f7a-9a6c-413bdee6b389.png) # Objective - Implement an alternative antialias technique - TAA scales based off of view resolution, not geometry complexity - TAA filters textures, firefly pixels, and other aliasing not covered by MSAA - TAA additionally will reduce noise / increase quality in future stochastic rendering techniques - Closes https://github.com/bevyengine/bevy/issues/3663 ## Solution - Add a temporal jitter component - Add a motion vector prepass - Add a TemporalAntialias component and plugin - Combine existing MSAA and FXAA examples and add TAA ## Followup Work - Prepass motion vector support for skinned meshes - Move uniforms needed for motion vectors into a separate bind group, instead of using different bind group layouts - Reuse previous frame's GPU view buffer for motion vectors, instead of recomputing - Mip biasing for sharper textures, and or unjitter texture UVs https://github.com/bevyengine/bevy/issues/7323 - Compute shader for better performance - Investigate FSR techniques - Historical depth based disocclusion tests, for geometry disocclusion - Historical luminance/hue based tests, for shading disocclusion - Pixel "locks" to reduce blending rate / revamp history confidence mechanism - Orthographic camera support for TemporalJitter - Figure out COD's 1-tap bicubic filter --- ## Changelog - Added MotionVectorPrepass and TemporalJitter - Added TemporalAntialiasPlugin, TemporalAntialiasBundle, and TemporalAntialiasSettings --------- Co-authored-by: IceSentry <c.giguere42@gmail.com> Co-authored-by: IceSentry <IceSentry@users.noreply.github.com> Co-authored-by: Robert Swain <robert.swain@gmail.com> Co-authored-by: Daniel Chia <danstryder@gmail.com> Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com> Co-authored-by: Brandon Dyer <brandondyer64@gmail.com> Co-authored-by: Edgar Geier <geieredgar@gmail.com>
2023-03-27 22:22:40 +00:00
[[example]]
name = "anti_aliasing"
path = "examples/3d/anti_aliasing.rs"
doc-scrape-examples = true
Temporal Antialiasing (TAA) (#7291) ![image](https://user-images.githubusercontent.com/47158642/214374911-412f0986-3927-4f7a-9a6c-413bdee6b389.png) # Objective - Implement an alternative antialias technique - TAA scales based off of view resolution, not geometry complexity - TAA filters textures, firefly pixels, and other aliasing not covered by MSAA - TAA additionally will reduce noise / increase quality in future stochastic rendering techniques - Closes https://github.com/bevyengine/bevy/issues/3663 ## Solution - Add a temporal jitter component - Add a motion vector prepass - Add a TemporalAntialias component and plugin - Combine existing MSAA and FXAA examples and add TAA ## Followup Work - Prepass motion vector support for skinned meshes - Move uniforms needed for motion vectors into a separate bind group, instead of using different bind group layouts - Reuse previous frame's GPU view buffer for motion vectors, instead of recomputing - Mip biasing for sharper textures, and or unjitter texture UVs https://github.com/bevyengine/bevy/issues/7323 - Compute shader for better performance - Investigate FSR techniques - Historical depth based disocclusion tests, for geometry disocclusion - Historical luminance/hue based tests, for shading disocclusion - Pixel "locks" to reduce blending rate / revamp history confidence mechanism - Orthographic camera support for TemporalJitter - Figure out COD's 1-tap bicubic filter --- ## Changelog - Added MotionVectorPrepass and TemporalJitter - Added TemporalAntialiasPlugin, TemporalAntialiasBundle, and TemporalAntialiasSettings --------- Co-authored-by: IceSentry <c.giguere42@gmail.com> Co-authored-by: IceSentry <IceSentry@users.noreply.github.com> Co-authored-by: Robert Swain <robert.swain@gmail.com> Co-authored-by: Daniel Chia <danstryder@gmail.com> Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com> Co-authored-by: Brandon Dyer <brandondyer64@gmail.com> Co-authored-by: Edgar Geier <geieredgar@gmail.com>
2023-03-27 22:22:40 +00:00
[package.metadata.example.anti_aliasing]
name = "Anti-aliasing"
description = "Compares different anti-aliasing methods"
category = "3D Rendering"
wasm = false
Immediate Mode Line/Gizmo Drawing (#6529) # Objective Add a convenient immediate mode drawing API for visual debugging. Fixes #5619 Alternative to #1625 Partial alternative to #5734 Based off https://github.com/Toqozz/bevy_debug_lines with some changes: * Simultaneous support for 2D and 3D. * Methods for basic shapes; circles, spheres, rectangles, boxes, etc. * 2D methods. * Removed durations. Seemed niche, and can be handled by users. <details> <summary>Performance</summary> Stress tested using Bevy's recommended optimization settings for the dev profile with the following command. ```bash cargo run --example many_debug_lines \ --config "profile.dev.package.\"*\".opt-level=3" \ --config "profile.dev.opt-level=1" ``` I dipped to 65-70 FPS at 300,000 lines CPU: 3700x RAM Speed: 3200 Mhz GPU: 2070 super - probably not very relevant, mostly cpu/memory bound </details> <details> <summary>Fancy bloom screenshot</summary> ![Screenshot_20230207_155033](https://user-images.githubusercontent.com/29694403/217291980-f1e0500e-7a14-4131-8c96-eaaaf52596ae.png) </details> ## Changelog * Added `GizmoPlugin` * Added `Gizmos` system parameter for drawing lines and wireshapes. ### TODO - [ ] Update changelog - [x] Update performance numbers - [x] Add credit to PR description ### Future work - Cache rendering primitives instead of constructing them out of line segments each frame. - Support for drawing solid meshes - Interactions. (See [bevy_mod_gizmos](https://github.com/LiamGallagher737/bevy_mod_gizmos)) - Fancier line drawing. (See [bevy_polyline](https://github.com/ForesightMiningSoftwareCorporation/bevy_polyline)) - Support for `RenderLayers` - Display gizmos for a certain duration. Currently everything displays for one frame (ie. immediate mode) - Changing settings per drawn item like drawing on top or drawing to different `RenderLayers` Co-Authored By: @lassade <felipe.jorge.pereira@gmail.com> Co-Authored By: @The5-1 <agaku@hotmail.de> Co-Authored By: @Toqozz <toqoz@hotmail.com> Co-Authored By: @nicopap <nico@nicopap.ch> --------- Co-authored-by: Robert Swain <robert.swain@gmail.com> Co-authored-by: IceSentry <c.giguere42@gmail.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2023-03-20 20:57:54 +00:00
[[example]]
name = "3d_gizmos"
path = "examples/3d/3d_gizmos.rs"
doc-scrape-examples = true
Immediate Mode Line/Gizmo Drawing (#6529) # Objective Add a convenient immediate mode drawing API for visual debugging. Fixes #5619 Alternative to #1625 Partial alternative to #5734 Based off https://github.com/Toqozz/bevy_debug_lines with some changes: * Simultaneous support for 2D and 3D. * Methods for basic shapes; circles, spheres, rectangles, boxes, etc. * 2D methods. * Removed durations. Seemed niche, and can be handled by users. <details> <summary>Performance</summary> Stress tested using Bevy's recommended optimization settings for the dev profile with the following command. ```bash cargo run --example many_debug_lines \ --config "profile.dev.package.\"*\".opt-level=3" \ --config "profile.dev.opt-level=1" ``` I dipped to 65-70 FPS at 300,000 lines CPU: 3700x RAM Speed: 3200 Mhz GPU: 2070 super - probably not very relevant, mostly cpu/memory bound </details> <details> <summary>Fancy bloom screenshot</summary> ![Screenshot_20230207_155033](https://user-images.githubusercontent.com/29694403/217291980-f1e0500e-7a14-4131-8c96-eaaaf52596ae.png) </details> ## Changelog * Added `GizmoPlugin` * Added `Gizmos` system parameter for drawing lines and wireshapes. ### TODO - [ ] Update changelog - [x] Update performance numbers - [x] Add credit to PR description ### Future work - Cache rendering primitives instead of constructing them out of line segments each frame. - Support for drawing solid meshes - Interactions. (See [bevy_mod_gizmos](https://github.com/LiamGallagher737/bevy_mod_gizmos)) - Fancier line drawing. (See [bevy_polyline](https://github.com/ForesightMiningSoftwareCorporation/bevy_polyline)) - Support for `RenderLayers` - Display gizmos for a certain duration. Currently everything displays for one frame (ie. immediate mode) - Changing settings per drawn item like drawing on top or drawing to different `RenderLayers` Co-Authored By: @lassade <felipe.jorge.pereira@gmail.com> Co-Authored By: @The5-1 <agaku@hotmail.de> Co-Authored By: @Toqozz <toqoz@hotmail.com> Co-Authored By: @nicopap <nico@nicopap.ch> --------- Co-authored-by: Robert Swain <robert.swain@gmail.com> Co-authored-by: IceSentry <c.giguere42@gmail.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2023-03-20 20:57:54 +00:00
[package.metadata.example.3d_gizmos]
name = "3D Gizmos"
description = "A scene showcasing 3D gizmos"
category = "3D Rendering"
wasm = true
Add Distance and Atmospheric Fog support (#6412) <img width="1392" alt="image" src="https://user-images.githubusercontent.com/418473/203873533-44c029af-13b7-4740-8ea3-af96bd5867c9.png"> <img width="1392" alt="image" src="https://user-images.githubusercontent.com/418473/203873549-36be7a23-b341-42a2-8a9f-ceea8ac7a2b8.png"> # Objective - Add support for the “classic” distance fog effect, as well as a more advanced atmospheric fog effect. ## Solution This PR: - Introduces a new `FogSettings` component that controls distance fog per-camera. - Adds support for three widely used “traditional” fog falloff modes: `Linear`, `Exponential` and `ExponentialSquared`, as well as a more advanced `Atmospheric` fog; - Adds support for directional light influence over fog color; - Extracts fog via `ExtractComponent`, then uses a prepare system that sets up a new dynamic uniform struct (`Fog`), similar to other mesh view types; - Renders fog in PBR material shader, as a final adjustment to the `output_color`, after PBR is computed (but before tone mapping); - Adds a new `StandardMaterial` flag to enable fog; (`fog_enabled`) - Adds convenience methods for easier artistic control when creating non-linear fog types; - Adds documentation around fog. --- ## Changelog ### Added - Added support for distance-based fog effects for PBR materials, controllable per-camera via the new `FogSettings` component; - Added `FogFalloff` enum for selecting between three widely used “traditional” fog falloff modes: `Linear`, `Exponential` and `ExponentialSquared`, as well as a more advanced `Atmospheric` fog;
2023-01-29 15:28:56 +00:00
[[example]]
name = "atmospheric_fog"
path = "examples/3d/atmospheric_fog.rs"
doc-scrape-examples = true
Add Distance and Atmospheric Fog support (#6412) <img width="1392" alt="image" src="https://user-images.githubusercontent.com/418473/203873533-44c029af-13b7-4740-8ea3-af96bd5867c9.png"> <img width="1392" alt="image" src="https://user-images.githubusercontent.com/418473/203873549-36be7a23-b341-42a2-8a9f-ceea8ac7a2b8.png"> # Objective - Add support for the “classic” distance fog effect, as well as a more advanced atmospheric fog effect. ## Solution This PR: - Introduces a new `FogSettings` component that controls distance fog per-camera. - Adds support for three widely used “traditional” fog falloff modes: `Linear`, `Exponential` and `ExponentialSquared`, as well as a more advanced `Atmospheric` fog; - Adds support for directional light influence over fog color; - Extracts fog via `ExtractComponent`, then uses a prepare system that sets up a new dynamic uniform struct (`Fog`), similar to other mesh view types; - Renders fog in PBR material shader, as a final adjustment to the `output_color`, after PBR is computed (but before tone mapping); - Adds a new `StandardMaterial` flag to enable fog; (`fog_enabled`) - Adds convenience methods for easier artistic control when creating non-linear fog types; - Adds documentation around fog. --- ## Changelog ### Added - Added support for distance-based fog effects for PBR materials, controllable per-camera via the new `FogSettings` component; - Added `FogFalloff` enum for selecting between three widely used “traditional” fog falloff modes: `Linear`, `Exponential` and `ExponentialSquared`, as well as a more advanced `Atmospheric` fog;
2023-01-29 15:28:56 +00:00
[package.metadata.example.atmospheric_fog]
name = "Atmospheric Fog"
description = "A scene showcasing the atmospheric fog effect"
category = "3D Rendering"
wasm = true
[[example]]
name = "fog"
path = "examples/3d/fog.rs"
doc-scrape-examples = true
Add Distance and Atmospheric Fog support (#6412) <img width="1392" alt="image" src="https://user-images.githubusercontent.com/418473/203873533-44c029af-13b7-4740-8ea3-af96bd5867c9.png"> <img width="1392" alt="image" src="https://user-images.githubusercontent.com/418473/203873549-36be7a23-b341-42a2-8a9f-ceea8ac7a2b8.png"> # Objective - Add support for the “classic” distance fog effect, as well as a more advanced atmospheric fog effect. ## Solution This PR: - Introduces a new `FogSettings` component that controls distance fog per-camera. - Adds support for three widely used “traditional” fog falloff modes: `Linear`, `Exponential` and `ExponentialSquared`, as well as a more advanced `Atmospheric` fog; - Adds support for directional light influence over fog color; - Extracts fog via `ExtractComponent`, then uses a prepare system that sets up a new dynamic uniform struct (`Fog`), similar to other mesh view types; - Renders fog in PBR material shader, as a final adjustment to the `output_color`, after PBR is computed (but before tone mapping); - Adds a new `StandardMaterial` flag to enable fog; (`fog_enabled`) - Adds convenience methods for easier artistic control when creating non-linear fog types; - Adds documentation around fog. --- ## Changelog ### Added - Added support for distance-based fog effects for PBR materials, controllable per-camera via the new `FogSettings` component; - Added `FogFalloff` enum for selecting between three widely used “traditional” fog falloff modes: `Linear`, `Exponential` and `ExponentialSquared`, as well as a more advanced `Atmospheric` fog;
2023-01-29 15:28:56 +00:00
[package.metadata.example.fog]
name = "Fog"
description = "A scene showcasing the distance fog effect"
category = "3D Rendering"
wasm = true
Standard Material Blend Modes (#6644) # Objective - This PR adds support for blend modes to the PBR `StandardMaterial`. <img width="1392" alt="Screenshot 2022-11-18 at 20 00 56" src="https://user-images.githubusercontent.com/418473/202820627-0636219a-a1e5-437a-b08b-b08c6856bf9c.png"> <img width="1392" alt="Screenshot 2022-11-18 at 20 01 01" src="https://user-images.githubusercontent.com/418473/202820615-c8d43301-9a57-49c4-bd21-4ae343c3e9ec.png"> ## Solution - The existing `AlphaMode` enum is extended, adding three more modes: `AlphaMode::Premultiplied`, `AlphaMode::Add` and `AlphaMode::Multiply`; - All new modes are rendered in the existing `Transparent3d` phase; - The existing mesh flags for alpha mode are reorganized for a more compact/efficient representation, and new values are added; - `MeshPipelineKey::TRANSPARENT_MAIN_PASS` is refactored into `MeshPipelineKey::BLEND_BITS`. - `AlphaMode::Opaque` and `AlphaMode::Mask(f32)` share a single opaque pipeline key: `MeshPipelineKey::BLEND_OPAQUE`; - `Blend`, `Premultiplied` and `Add` share a single premultiplied alpha pipeline key, `MeshPipelineKey::BLEND_PREMULTIPLIED_ALPHA`. In the shader, color values are premultiplied accordingly (or not) depending on the blend mode to produce the three different results after PBR/tone mapping/dithering; - `Multiply` uses its own independent pipeline key, `MeshPipelineKey::BLEND_MULTIPLY`; - Example and documentation are provided. --- ## Changelog ### Added - Added support for additive and multiplicative blend modes in the PBR `StandardMaterial`, via `AlphaMode::Add` and `AlphaMode::Multiply`; - Added support for premultiplied alpha in the PBR `StandardMaterial`, via `AlphaMode::Premultiplied`;
2023-01-21 21:46:53 +00:00
[[example]]
name = "blend_modes"
path = "examples/3d/blend_modes.rs"
doc-scrape-examples = true
Standard Material Blend Modes (#6644) # Objective - This PR adds support for blend modes to the PBR `StandardMaterial`. <img width="1392" alt="Screenshot 2022-11-18 at 20 00 56" src="https://user-images.githubusercontent.com/418473/202820627-0636219a-a1e5-437a-b08b-b08c6856bf9c.png"> <img width="1392" alt="Screenshot 2022-11-18 at 20 01 01" src="https://user-images.githubusercontent.com/418473/202820615-c8d43301-9a57-49c4-bd21-4ae343c3e9ec.png"> ## Solution - The existing `AlphaMode` enum is extended, adding three more modes: `AlphaMode::Premultiplied`, `AlphaMode::Add` and `AlphaMode::Multiply`; - All new modes are rendered in the existing `Transparent3d` phase; - The existing mesh flags for alpha mode are reorganized for a more compact/efficient representation, and new values are added; - `MeshPipelineKey::TRANSPARENT_MAIN_PASS` is refactored into `MeshPipelineKey::BLEND_BITS`. - `AlphaMode::Opaque` and `AlphaMode::Mask(f32)` share a single opaque pipeline key: `MeshPipelineKey::BLEND_OPAQUE`; - `Blend`, `Premultiplied` and `Add` share a single premultiplied alpha pipeline key, `MeshPipelineKey::BLEND_PREMULTIPLIED_ALPHA`. In the shader, color values are premultiplied accordingly (or not) depending on the blend mode to produce the three different results after PBR/tone mapping/dithering; - `Multiply` uses its own independent pipeline key, `MeshPipelineKey::BLEND_MULTIPLY`; - Example and documentation are provided. --- ## Changelog ### Added - Added support for additive and multiplicative blend modes in the PBR `StandardMaterial`, via `AlphaMode::Add` and `AlphaMode::Multiply`; - Added support for premultiplied alpha in the PBR `StandardMaterial`, via `AlphaMode::Premultiplied`;
2023-01-21 21:46:53 +00:00
[package.metadata.example.blend_modes]
name = "Blend Modes"
description = "Showcases different blend modes"
category = "3D Rendering"
wasm = true
2021-06-02 02:59:17 +00:00
[[example]]
name = "lighting"
path = "examples/3d/lighting.rs"
doc-scrape-examples = true
[package.metadata.example.lighting]
name = "Lighting"
description = "Illustrates various lighting options in a simple scene"
category = "3D Rendering"
wasm = true
[[example]]
name = "lines"
path = "examples/3d/lines.rs"
doc-scrape-examples = true
[package.metadata.example.lines]
name = "Lines"
description = "Create a custom material to draw 3d lines"
category = "3D Rendering"
wasm = true
Screen Space Ambient Occlusion (SSAO) MVP (#7402) ![image](https://github.com/bevyengine/bevy/assets/47158642/dbb62645-f639-4f2b-b84b-26fd915c186d) # Objective - Add Screen space ambient occlusion (SSAO). SSAO approximates small-scale, local occlusion of _indirect_ diffuse light between objects. SSAO does not apply to direct lighting, such as point or directional lights. - This darkens creases, e.g. on staircases, and gives nice contact shadows where objects meet, giving entities a more "grounded" feel. - Closes https://github.com/bevyengine/bevy/issues/3632. ## Solution - Implement the GTAO algorithm. - https://www.activision.com/cdn/research/Practical_Real_Time_Strategies_for_Accurate_Indirect_Occlusion_NEW%20VERSION_COLOR.pdf - https://blog.selfshadow.com/publications/s2016-shading-course/activision/s2016_pbs_activision_occlusion.pdf - Source code heavily based on [Intel's XeGTAO](https://github.com/GameTechDev/XeGTAO/blob/0d177ce06bfa642f64d8af4de1197ad1bcb862d4/Source/Rendering/Shaders/XeGTAO.hlsli). - Add an SSAO bevy example. ## Algorithm Overview * Run a depth and normal prepass * Create downscaled mips of the depth texture (preprocess_depths pass) * GTAO pass - for each pixel, take several random samples from the depth+normal buffers, reconstruct world position, raytrace in screen space to estimate occlusion. Rather then doing completely random samples on a hemisphere, you choose random _slices_ of the hemisphere, and then can analytically compute the full occlusion of that slice. Also compute edges based on depth differences here. * Spatial denoise pass - bilateral blur, using edge detection to not blur over edges. This is the final SSAO result. * Main pass - if SSAO exists, sample the SSAO texture, and set occlusion to be the minimum of ssao/material occlusion. This then feeds into the rest of the PBR shader as normal. --- ## Future Improvements - Maybe remove the low quality preset for now (too noisy) - WebGPU fallback (see below) - Faster depth->world position (see reverted code) - Bent normals - Try interleaved gradient noise or spatiotemporal blue noise - Replace the spatial denoiser with a combined spatial+temporal denoiser - Render at half resolution and use a bilateral upsample - Better multibounce approximation (https://drive.google.com/file/d/1SyagcEVplIm2KkRD3WQYSO9O0Iyi1hfy/view) ## Far-Future Performance Improvements - F16 math (missing naga-wgsl support https://github.com/gfx-rs/naga/issues/1884) - Faster coordinate space conversion for normals - Faster depth mipchain creation (https://github.com/GPUOpen-Effects/FidelityFX-SPD) (wgpu/naga does not currently support subgroup ops) - Deinterleaved SSAO for better cache efficiency (https://developer.nvidia.com/sites/default/files/akamai/gameworks/samples/DeinterleavedTexturing.pdf) ## Other Interesting Papers - Visibility bitmask (https://link.springer.com/article/10.1007/s00371-022-02703-y, https://cdrinmatane.github.io/posts/cgspotlight-slides/) - Screen space diffuse lighting (https://github.com/Patapom/GodComplex/blob/master/Tests/TestHBIL/2018%20Mayaux%20-%20Horizon-Based%20Indirect%20Lighting%20(HBIL).pdf) ## Platform Support * SSAO currently does not work on DirectX12 due to issues with wgpu and naga: * https://github.com/gfx-rs/wgpu/pull/3798 * https://github.com/gfx-rs/naga/pull/2353 * SSAO currently does not work on WebGPU because r16float is not a valid storage texture format https://gpuweb.github.io/gpuweb/wgsl/#storage-texel-formats. We can fix this with a fallback to r32float. --- ## Changelog - Added ScreenSpaceAmbientOcclusionSettings, ScreenSpaceAmbientOcclusionQualityLevel, and ScreenSpaceAmbientOcclusionBundle --------- Co-authored-by: IceSentry <c.giguere42@gmail.com> Co-authored-by: IceSentry <IceSentry@users.noreply.github.com> Co-authored-by: Daniel Chia <danstryder@gmail.com> Co-authored-by: Elabajaba <Elabajaba@users.noreply.github.com> Co-authored-by: Robert Swain <robert.swain@gmail.com> Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com> Co-authored-by: Brandon Dyer <brandondyer64@gmail.com> Co-authored-by: Edgar Geier <geieredgar@gmail.com> Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2023-06-18 21:05:55 +00:00
[[example]]
name = "ssao"
path = "examples/3d/ssao.rs"
doc-scrape-examples = true
Screen Space Ambient Occlusion (SSAO) MVP (#7402) ![image](https://github.com/bevyengine/bevy/assets/47158642/dbb62645-f639-4f2b-b84b-26fd915c186d) # Objective - Add Screen space ambient occlusion (SSAO). SSAO approximates small-scale, local occlusion of _indirect_ diffuse light between objects. SSAO does not apply to direct lighting, such as point or directional lights. - This darkens creases, e.g. on staircases, and gives nice contact shadows where objects meet, giving entities a more "grounded" feel. - Closes https://github.com/bevyengine/bevy/issues/3632. ## Solution - Implement the GTAO algorithm. - https://www.activision.com/cdn/research/Practical_Real_Time_Strategies_for_Accurate_Indirect_Occlusion_NEW%20VERSION_COLOR.pdf - https://blog.selfshadow.com/publications/s2016-shading-course/activision/s2016_pbs_activision_occlusion.pdf - Source code heavily based on [Intel's XeGTAO](https://github.com/GameTechDev/XeGTAO/blob/0d177ce06bfa642f64d8af4de1197ad1bcb862d4/Source/Rendering/Shaders/XeGTAO.hlsli). - Add an SSAO bevy example. ## Algorithm Overview * Run a depth and normal prepass * Create downscaled mips of the depth texture (preprocess_depths pass) * GTAO pass - for each pixel, take several random samples from the depth+normal buffers, reconstruct world position, raytrace in screen space to estimate occlusion. Rather then doing completely random samples on a hemisphere, you choose random _slices_ of the hemisphere, and then can analytically compute the full occlusion of that slice. Also compute edges based on depth differences here. * Spatial denoise pass - bilateral blur, using edge detection to not blur over edges. This is the final SSAO result. * Main pass - if SSAO exists, sample the SSAO texture, and set occlusion to be the minimum of ssao/material occlusion. This then feeds into the rest of the PBR shader as normal. --- ## Future Improvements - Maybe remove the low quality preset for now (too noisy) - WebGPU fallback (see below) - Faster depth->world position (see reverted code) - Bent normals - Try interleaved gradient noise or spatiotemporal blue noise - Replace the spatial denoiser with a combined spatial+temporal denoiser - Render at half resolution and use a bilateral upsample - Better multibounce approximation (https://drive.google.com/file/d/1SyagcEVplIm2KkRD3WQYSO9O0Iyi1hfy/view) ## Far-Future Performance Improvements - F16 math (missing naga-wgsl support https://github.com/gfx-rs/naga/issues/1884) - Faster coordinate space conversion for normals - Faster depth mipchain creation (https://github.com/GPUOpen-Effects/FidelityFX-SPD) (wgpu/naga does not currently support subgroup ops) - Deinterleaved SSAO for better cache efficiency (https://developer.nvidia.com/sites/default/files/akamai/gameworks/samples/DeinterleavedTexturing.pdf) ## Other Interesting Papers - Visibility bitmask (https://link.springer.com/article/10.1007/s00371-022-02703-y, https://cdrinmatane.github.io/posts/cgspotlight-slides/) - Screen space diffuse lighting (https://github.com/Patapom/GodComplex/blob/master/Tests/TestHBIL/2018%20Mayaux%20-%20Horizon-Based%20Indirect%20Lighting%20(HBIL).pdf) ## Platform Support * SSAO currently does not work on DirectX12 due to issues with wgpu and naga: * https://github.com/gfx-rs/wgpu/pull/3798 * https://github.com/gfx-rs/naga/pull/2353 * SSAO currently does not work on WebGPU because r16float is not a valid storage texture format https://gpuweb.github.io/gpuweb/wgsl/#storage-texel-formats. We can fix this with a fallback to r32float. --- ## Changelog - Added ScreenSpaceAmbientOcclusionSettings, ScreenSpaceAmbientOcclusionQualityLevel, and ScreenSpaceAmbientOcclusionBundle --------- Co-authored-by: IceSentry <c.giguere42@gmail.com> Co-authored-by: IceSentry <IceSentry@users.noreply.github.com> Co-authored-by: Daniel Chia <danstryder@gmail.com> Co-authored-by: Elabajaba <Elabajaba@users.noreply.github.com> Co-authored-by: Robert Swain <robert.swain@gmail.com> Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com> Co-authored-by: Brandon Dyer <brandondyer64@gmail.com> Co-authored-by: Edgar Geier <geieredgar@gmail.com> Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2023-06-18 21:05:55 +00:00
[package.metadata.example.ssao]
name = "Screen Space Ambient Occlusion"
description = "A scene showcasing screen space ambient occlusion"
category = "3D Rendering"
wasm = false
Spotlights (#4715) # Objective add spotlight support ## Solution / Changelog - add spotlight angles (inner, outer) to ``PointLight`` struct. emitted light is linearly attenuated from 100% to 0% as angle tends from inner to outer. Direction is taken from the existing transform rotation. - add spotlight direction (vec3) and angles (f32,f32) to ``GpuPointLight`` struct (60 bytes -> 80 bytes) in ``pbr/render/lights.rs`` and ``mesh_view_bind_group.wgsl`` - reduce no-buffer-support max point light count to 204 due to above - use spotlight data to attenuate light in ``pbr.wgsl`` - do additional cluster culling on spotlights to minimise cost in ``assign_lights_to_clusters`` - changed one of the lights in the lighting demo to a spotlight - also added a ``spotlight`` demo - probably not justified but so reviewers can see it more easily ## notes increasing the size of the GpuPointLight struct on my machine reduces the FPS of ``many_lights -- sphere`` from ~150fps to 140fps. i thought this was a reasonable tradeoff, and felt better than handling spotlights separately which is possible but would mean introducing a new bind group, refactoring light-assignment code and adding new spotlight-specific code in pbr.wgsl. the FPS impact for smaller numbers of lights should be very small. the cluster culling strategy reintroduces the cluster aabb code which was recently removed... sorry. the aabb is used to get a cluster bounding sphere, which can then be tested fairly efficiently using the strategy described at the end of https://bartwronski.com/2017/04/13/cull-that-cone/. this works well with roughly cubic clusters (where the cluster z size is close to the same as x/y size), less well for other cases like single Z slice / tiled forward rendering. In the worst case we will end up just keeping the culling of the equivalent point light. Co-authored-by: François <mockersf@gmail.com>
2022-07-08 19:57:43 +00:00
[[example]]
name = "spotlight"
path = "examples/3d/spotlight.rs"
doc-scrape-examples = true
Spotlights (#4715) # Objective add spotlight support ## Solution / Changelog - add spotlight angles (inner, outer) to ``PointLight`` struct. emitted light is linearly attenuated from 100% to 0% as angle tends from inner to outer. Direction is taken from the existing transform rotation. - add spotlight direction (vec3) and angles (f32,f32) to ``GpuPointLight`` struct (60 bytes -> 80 bytes) in ``pbr/render/lights.rs`` and ``mesh_view_bind_group.wgsl`` - reduce no-buffer-support max point light count to 204 due to above - use spotlight data to attenuate light in ``pbr.wgsl`` - do additional cluster culling on spotlights to minimise cost in ``assign_lights_to_clusters`` - changed one of the lights in the lighting demo to a spotlight - also added a ``spotlight`` demo - probably not justified but so reviewers can see it more easily ## notes increasing the size of the GpuPointLight struct on my machine reduces the FPS of ``many_lights -- sphere`` from ~150fps to 140fps. i thought this was a reasonable tradeoff, and felt better than handling spotlights separately which is possible but would mean introducing a new bind group, refactoring light-assignment code and adding new spotlight-specific code in pbr.wgsl. the FPS impact for smaller numbers of lights should be very small. the cluster culling strategy reintroduces the cluster aabb code which was recently removed... sorry. the aabb is used to get a cluster bounding sphere, which can then be tested fairly efficiently using the strategy described at the end of https://bartwronski.com/2017/04/13/cull-that-cone/. this works well with roughly cubic clusters (where the cluster z size is close to the same as x/y size), less well for other cases like single Z slice / tiled forward rendering. In the worst case we will end up just keeping the culling of the equivalent point light. Co-authored-by: François <mockersf@gmail.com>
2022-07-08 19:57:43 +00:00
[package.metadata.example.spotlight]
name = "Spotlight"
description = "Illustrates spot lights"
category = "3D Rendering"
wasm = true
[[example]]
Revamp Bloom (#6677) ![image](https://user-images.githubusercontent.com/47158642/220197588-25e11022-02e4-45f3-b2e5-392c4ce7a025.png) Huge credit to @StarLederer, who did almost all of the work on this. We're just reusing this PR to keep everything in one place. # Objective 1. Make bloom more physically based. 1. Improve artistic control. 1. Allow to use bloom as screen blur. 1. Fix #6634. 1. Address #6655 (although the author makes incorrect conclusions). ## Solution 1. Set the default threshold to 0. 2. Lerp between bloom textures when `composite_mode: BloomCompositeMode::EnergyConserving`. 1. Use [a parametric function](https://starlederer.github.io/bloom) to control blend levels for each bloom texture. In the future this can be controlled per-pixel for things like lens dirt. 3. Implement BloomCompositeMode::Additive` for situations where the old school look is desired. ## Changelog * Bloom now looks different. * Added `BloomSettings:lf_boost`, `BloomSettings:lf_boost_curvature`, `BloomSettings::high_pass_frequency` and `BloomSettings::composite_mode`. * `BloomSettings::scale` removed. * `BloomSettings::knee` renamed to `BloomPrefilterSettings::softness`. * `BloomSettings::threshold` renamed to `BloomPrefilterSettings::threshold`. * The bloom example has been renamed to bloom_3d and improved. A bloom_2d example was added. ## Migration Guide * Refactor mentions of `BloomSettings::knee` and `BloomSettings::threshold` as `BloomSettings::prefilter_settings` where knee is now `softness`. * If defined without `..default()` add `..default()` to definitions of `BloomSettings` instances or manually define missing fields. * Adapt to Bloom looking visually different (if needed). Co-authored-by: Herman Lederer <germans.lederers@gmail.com>
2023-03-04 12:05:26 +00:00
name = "bloom_3d"
path = "examples/3d/bloom_3d.rs"
doc-scrape-examples = true
Revamp Bloom (#6677) ![image](https://user-images.githubusercontent.com/47158642/220197588-25e11022-02e4-45f3-b2e5-392c4ce7a025.png) Huge credit to @StarLederer, who did almost all of the work on this. We're just reusing this PR to keep everything in one place. # Objective 1. Make bloom more physically based. 1. Improve artistic control. 1. Allow to use bloom as screen blur. 1. Fix #6634. 1. Address #6655 (although the author makes incorrect conclusions). ## Solution 1. Set the default threshold to 0. 2. Lerp between bloom textures when `composite_mode: BloomCompositeMode::EnergyConserving`. 1. Use [a parametric function](https://starlederer.github.io/bloom) to control blend levels for each bloom texture. In the future this can be controlled per-pixel for things like lens dirt. 3. Implement BloomCompositeMode::Additive` for situations where the old school look is desired. ## Changelog * Bloom now looks different. * Added `BloomSettings:lf_boost`, `BloomSettings:lf_boost_curvature`, `BloomSettings::high_pass_frequency` and `BloomSettings::composite_mode`. * `BloomSettings::scale` removed. * `BloomSettings::knee` renamed to `BloomPrefilterSettings::softness`. * `BloomSettings::threshold` renamed to `BloomPrefilterSettings::threshold`. * The bloom example has been renamed to bloom_3d and improved. A bloom_2d example was added. ## Migration Guide * Refactor mentions of `BloomSettings::knee` and `BloomSettings::threshold` as `BloomSettings::prefilter_settings` where knee is now `softness`. * If defined without `..default()` add `..default()` to definitions of `BloomSettings` instances or manually define missing fields. * Adapt to Bloom looking visually different (if needed). Co-authored-by: Herman Lederer <germans.lederers@gmail.com>
2023-03-04 12:05:26 +00:00
[package.metadata.example.bloom_3d]
name = "3D Bloom"
description = "Illustrates bloom configuration using HDR and emissive materials"
category = "3D Rendering"
wasm = true
Deferred Renderer (#9258) # Objective - Add a [Deferred Renderer](https://en.wikipedia.org/wiki/Deferred_shading) to Bevy. - This allows subsequent passes to access per pixel material information before/during shading. - Accessing this per pixel material information is needed for some features, like GI. It also makes other features (ex. Decals) simpler to implement and/or improves their capability. There are multiple approaches to accomplishing this. The deferred shading approach works well given the limitations of WebGPU and WebGL2. Motivation: [I'm working on a GI solution for Bevy](https://youtu.be/eH1AkL-mwhI) # Solution - The deferred renderer is implemented with a prepass and a deferred lighting pass. - The prepass renders opaque objects into the Gbuffer attachment (`Rgba32Uint`). The PBR shader generates a `PbrInput` in mostly the same way as the forward implementation and then [packs it into the Gbuffer](https://github.com/DGriffin91/bevy/blob/ec1465559f2c82001830e908fc02ff1d7c2efe51/crates/bevy_pbr/src/render/pbr.wgsl#L168). - The deferred lighting pass unpacks the `PbrInput` and [feeds it into the pbr() function](https://github.com/DGriffin91/bevy/blob/ec1465559f2c82001830e908fc02ff1d7c2efe51/crates/bevy_pbr/src/deferred/deferred_lighting.wgsl#L65), then outputs the shaded color data. - There is now a resource [DefaultOpaqueRendererMethod](https://github.com/DGriffin91/bevy/blob/ec1465559f2c82001830e908fc02ff1d7c2efe51/crates/bevy_pbr/src/material.rs#L599) that can be used to set the default render method for opaque materials. If materials return `None` from [opaque_render_method()](https://github.com/DGriffin91/bevy/blob/ec1465559f2c82001830e908fc02ff1d7c2efe51/crates/bevy_pbr/src/material.rs#L131) the `DefaultOpaqueRendererMethod` will be used. Otherwise, custom materials can also explicitly choose to only support Deferred or Forward by returning the respective [OpaqueRendererMethod](https://github.com/DGriffin91/bevy/blob/ec1465559f2c82001830e908fc02ff1d7c2efe51/crates/bevy_pbr/src/material.rs#L603) - Deferred materials can be used seamlessly along with both opaque and transparent forward rendered materials in the same scene. The [deferred rendering example](https://github.com/DGriffin91/bevy/blob/deferred/examples/3d/deferred_rendering.rs) does this. - The deferred renderer does not support MSAA. If any deferred materials are used, MSAA must be disabled. Both TAA and FXAA are supported. - Deferred rendering supports WebGL2/WebGPU. ## Custom deferred materials - Custom materials can support both deferred and forward at the same time. The [StandardMaterial](https://github.com/DGriffin91/bevy/blob/ec1465559f2c82001830e908fc02ff1d7c2efe51/crates/bevy_pbr/src/render/pbr.wgsl#L166) does this. So does [this example](https://github.com/DGriffin91/bevy_glowy_orb_tutorial/blob/deferred/assets/shaders/glowy.wgsl#L56). - Custom deferred materials that require PBR lighting can create a `PbrInput`, write it to the deferred GBuffer and let it be rendered by the `PBRDeferredLightingPlugin`. - Custom deferred materials that require custom lighting have two options: 1. Use the base_color channel of the `PbrInput` combined with the `STANDARD_MATERIAL_FLAGS_UNLIT_BIT` flag. [Example.](https://github.com/DGriffin91/bevy_glowy_orb_tutorial/blob/deferred/assets/shaders/glowy.wgsl#L56) (If the unlit bit is set, the base_color is stored as RGB9E5 for extra precision) 2. A Custom Deferred Lighting pass can be created, either overriding the default, or running in addition. The a depth buffer is used to limit rendering to only the required fragments for each deferred lighting pass. Materials can set their respective depth id via the [deferred_lighting_pass_id](https://github.com/DGriffin91/bevy/blob/b79182d2a32cac28c4213c2457a53ac2cc885332/crates/bevy_pbr/src/prepass/prepass_io.wgsl#L95) attachment. The custom deferred lighting pass plugin can then set [its corresponding depth](https://github.com/DGriffin91/bevy/blob/ec1465559f2c82001830e908fc02ff1d7c2efe51/crates/bevy_pbr/src/deferred/deferred_lighting.wgsl#L37). Then with the lighting pass using [CompareFunction::Equal](https://github.com/DGriffin91/bevy/blob/ec1465559f2c82001830e908fc02ff1d7c2efe51/crates/bevy_pbr/src/deferred/mod.rs#L335), only the fragments with a depth that equal the corresponding depth written in the material will be rendered. Custom deferred lighting plugins can also be created to render the StandardMaterial. The default deferred lighting plugin can be bypassed with `DefaultPlugins.set(PBRDeferredLightingPlugin { bypass: true })` --------- Co-authored-by: nickrart <nickolas.g.russell@gmail.com>
2023-10-12 22:10:38 +00:00
[[example]]
name = "deferred_rendering"
path = "examples/3d/deferred_rendering.rs"
[package.metadata.example.deferred_rendering]
name = "Deferred Rendering"
description = "Renders meshes with both forward and deferred pipelines"
category = "3D Rendering"
wasm = true
2020-05-01 20:12:47 +00:00
[[example]]
name = "load_gltf"
path = "examples/3d/load_gltf.rs"
doc-scrape-examples = true
2020-05-01 20:12:47 +00:00
[package.metadata.example.load_gltf]
name = "Load glTF"
description = "Loads and renders a glTF file as a scene"
category = "3D Rendering"
wasm = true
[[example]]
name = "tonemapping"
path = "examples/3d/tonemapping.rs"
doc-scrape-examples = true
[package.metadata.example.tonemapping]
name = "Tonemapping"
description = "Compares tonemapping options"
category = "3D Rendering"
wasm = true
[[example]]
name = "orthographic"
path = "examples/3d/orthographic.rs"
doc-scrape-examples = true
[package.metadata.example.orthographic]
name = "Orthographic View"
description = "Shows how to create a 3D orthographic view (for isometric-look in games or CAD applications)"
category = "3D Rendering"
wasm = true
2020-05-01 20:12:47 +00:00
[[example]]
name = "parenting"
path = "examples/3d/parenting.rs"
doc-scrape-examples = true
2020-05-01 20:12:47 +00:00
[package.metadata.example.parenting]
name = "Parenting"
description = "Demonstrates parent->child relationships and relative transformations"
category = "3D Rendering"
wasm = true
[[example]]
name = "pbr"
path = "examples/3d/pbr.rs"
doc-scrape-examples = true
[package.metadata.example.pbr]
name = "Physically Based Rendering"
description = "Demonstrates use of Physically Based Rendering (PBR) properties"
category = "3D Rendering"
wasm = true
Add parallax mapping to bevy PBR (#5928) # Objective Add a [parallax mapping] shader to bevy. Please note that this is a 3d technique, NOT a 2d sidescroller feature. ## Solution - Add related fields to `StandardMaterial` - update the pbr shader - Add an example taking advantage of parallax mapping A pre-existing implementation exists at: https://github.com/nicopap/bevy_mod_paramap/ The implementation is derived from: https://web.archive.org/web/20150419215321/http://sunandblackcat.com/tipFullView.php?l=eng&topicid=28 Further discussion on literature is found in the `bevy_mod_paramap` README. ### Limitations - The mesh silhouette isn't affected by the depth map. - The depth of the pixel does not reflect its visual position, resulting in artifacts for depth-dependent features such as fog or SSAO - GLTF does not define a height map texture, so somehow the user will always need to work around this limitation, though [an extension is in the works][gltf] ### Future work - It's possible to update the depth in the depth buffer to follow the parallaxed texture. This would enable interop with depth-based visual effects, it also allows `discard`ing pixels of materials when computed depth is higher than the one in depth buffer - Cheap lower quality single-sample method using [offset limiting] - Add distance fading, to disable parallaxing (relatively expensive) on distant objects - GLTF extension to allow defining height maps. Or a workaround implemented through a blender plugin to the GLTF exporter that uses the `extras` field to add height map. - [Quadratic surface vertex attributes][oliveira_3] to enable parallax mapping on bending surfaces and allow clean silhouetting. - noise based sampling, to limit the pancake artifacts. - Cone mapping ([GPU gems], [Simcity (2013)][simcity]). Requires preprocessing, increase depth map size, reduces sample count greatly. - [Quadtree parallax mapping][qpm] (also requires preprocessing) - Self-shadowing of parallax-mapped surfaces by modifying the shadow map - Generate depth map from normal map [link to slides], [blender question] https://user-images.githubusercontent.com/26321040/223563792-dffcc6ab-70e8-4ff9-90d1-b36c338695ad.mp4 [blender question]: https://blender.stackexchange.com/questions/89278/how-to-get-a-smooth-curvature-map-from-a-normal-map [link to slides]: https://developer.download.nvidia.com/assets/gamedev/docs/nmap2displacement.pdf [oliveira_3]: https://www.inf.ufrgs.br/~oliveira/pubs_files/Oliveira_Policarpo_RP-351_Jan_2005.pdf [GPU gems]: https://developer.nvidia.com/gpugems/gpugems3/part-iii-rendering/chapter-18-relaxed-cone-stepping-relief-mapping [simcity]: https://community.simtropolis.com/omnibus/other-games/building-and-rendering-simcity-2013-r247/ [offset limiting]: https://raw.githubusercontent.com/marcusstenbeck/tncg14-parallax-mapping/master/documents/Parallax%20Mapping%20with%20Offset%20Limiting%20-%20A%20Per-Pixel%20Approximation%20of%20Uneven%20Surfaces.pdf [gltf]: https://github.com/KhronosGroup/glTF/pull/2196 [qpm]: https://www.gamedevs.org/uploads/quadtree-displacement-mapping-with-height-blending.pdf --- ## Changelog - Add a `depth_map` field to the `StandardMaterial`, it is a grayscale image where white represents bottom and black the top. If `depth_map` is set, bevy's pbr shader will use it to do [parallax mapping] to give an increased feel of depth to the material. This is similar to a displacement map, but with infinite precision at fairly low cost. - The fields `parallax_mapping_method`, `parallax_depth_scale` and `max_parallax_layer_count` allow finer grained control over the behavior of the parallax shader. - Add the `parallax_mapping` example to show off the effect. [parallax mapping]: https://en.wikipedia.org/wiki/Parallax_mapping --------- Co-authored-by: Robert Swain <robert.swain@gmail.com>
2023-04-15 10:25:14 +00:00
[[example]]
name = "parallax_mapping"
path = "examples/3d/parallax_mapping.rs"
doc-scrape-examples = true
Add parallax mapping to bevy PBR (#5928) # Objective Add a [parallax mapping] shader to bevy. Please note that this is a 3d technique, NOT a 2d sidescroller feature. ## Solution - Add related fields to `StandardMaterial` - update the pbr shader - Add an example taking advantage of parallax mapping A pre-existing implementation exists at: https://github.com/nicopap/bevy_mod_paramap/ The implementation is derived from: https://web.archive.org/web/20150419215321/http://sunandblackcat.com/tipFullView.php?l=eng&topicid=28 Further discussion on literature is found in the `bevy_mod_paramap` README. ### Limitations - The mesh silhouette isn't affected by the depth map. - The depth of the pixel does not reflect its visual position, resulting in artifacts for depth-dependent features such as fog or SSAO - GLTF does not define a height map texture, so somehow the user will always need to work around this limitation, though [an extension is in the works][gltf] ### Future work - It's possible to update the depth in the depth buffer to follow the parallaxed texture. This would enable interop with depth-based visual effects, it also allows `discard`ing pixels of materials when computed depth is higher than the one in depth buffer - Cheap lower quality single-sample method using [offset limiting] - Add distance fading, to disable parallaxing (relatively expensive) on distant objects - GLTF extension to allow defining height maps. Or a workaround implemented through a blender plugin to the GLTF exporter that uses the `extras` field to add height map. - [Quadratic surface vertex attributes][oliveira_3] to enable parallax mapping on bending surfaces and allow clean silhouetting. - noise based sampling, to limit the pancake artifacts. - Cone mapping ([GPU gems], [Simcity (2013)][simcity]). Requires preprocessing, increase depth map size, reduces sample count greatly. - [Quadtree parallax mapping][qpm] (also requires preprocessing) - Self-shadowing of parallax-mapped surfaces by modifying the shadow map - Generate depth map from normal map [link to slides], [blender question] https://user-images.githubusercontent.com/26321040/223563792-dffcc6ab-70e8-4ff9-90d1-b36c338695ad.mp4 [blender question]: https://blender.stackexchange.com/questions/89278/how-to-get-a-smooth-curvature-map-from-a-normal-map [link to slides]: https://developer.download.nvidia.com/assets/gamedev/docs/nmap2displacement.pdf [oliveira_3]: https://www.inf.ufrgs.br/~oliveira/pubs_files/Oliveira_Policarpo_RP-351_Jan_2005.pdf [GPU gems]: https://developer.nvidia.com/gpugems/gpugems3/part-iii-rendering/chapter-18-relaxed-cone-stepping-relief-mapping [simcity]: https://community.simtropolis.com/omnibus/other-games/building-and-rendering-simcity-2013-r247/ [offset limiting]: https://raw.githubusercontent.com/marcusstenbeck/tncg14-parallax-mapping/master/documents/Parallax%20Mapping%20with%20Offset%20Limiting%20-%20A%20Per-Pixel%20Approximation%20of%20Uneven%20Surfaces.pdf [gltf]: https://github.com/KhronosGroup/glTF/pull/2196 [qpm]: https://www.gamedevs.org/uploads/quadtree-displacement-mapping-with-height-blending.pdf --- ## Changelog - Add a `depth_map` field to the `StandardMaterial`, it is a grayscale image where white represents bottom and black the top. If `depth_map` is set, bevy's pbr shader will use it to do [parallax mapping] to give an increased feel of depth to the material. This is similar to a displacement map, but with infinite precision at fairly low cost. - The fields `parallax_mapping_method`, `parallax_depth_scale` and `max_parallax_layer_count` allow finer grained control over the behavior of the parallax shader. - Add the `parallax_mapping` example to show off the effect. [parallax mapping]: https://en.wikipedia.org/wiki/Parallax_mapping --------- Co-authored-by: Robert Swain <robert.swain@gmail.com>
2023-04-15 10:25:14 +00:00
[package.metadata.example.parallax_mapping]
name = "Parallax Mapping"
description = "Demonstrates use of a normal map and depth map for parallax mapping"
category = "3D Rendering"
wasm = true
[[example]]
name = "render_to_texture"
path = "examples/3d/render_to_texture.rs"
doc-scrape-examples = true
[package.metadata.example.render_to_texture]
name = "Render to Texture"
description = "Shows how to render to a texture, useful for mirrors, UI, or exporting images"
category = "3D Rendering"
wasm = true
bevy_pbr2: Add support for most of the StandardMaterial textures (#4) * bevy_pbr2: Add support for most of the StandardMaterial textures Normal maps are not included here as they require tangents in a vertex attribute. * bevy_pbr2: Ensure RenderCommandQueue is ready for PbrShaders init * texture_pipelined: Add a light to the scene so we can see stuff * WIP bevy_pbr2: back to front sorting hack * bevy_pbr2: Uniform control flow for texture sampling in pbr.frag From 'fintelia' on the Bevy Render Rework Round 2 discussion: "My understanding is that GPUs these days never use the "execute both branches and select the result" strategy. Rather, what they do is evaluate the branch condition on all threads of a warp, and jump over it if all of them evaluate to false. If even a single thread needs to execute the if statement body, however, then the remaining threads are paused until that is completed." * bevy_pbr2: Simplify texture and sampler names The StandardMaterial_ prefix is no longer needed * bevy_pbr2: Match default 'AmbientColor' of current bevy_pbr for now * bevy_pbr2: Convert from non-linear to linear sRGB for the color uniform * bevy_pbr2: Add pbr_pipelined example * Fix view vector in pbr frag to work in ortho * bevy_pbr2: Use a 90 degree y fov and light range projection for lights * bevy_pbr2: Add AmbientLight resource * bevy_pbr2: Convert PointLight color to linear sRGB for use in fragment shader * bevy_pbr2: pbr.frag: Rename PointLight.projection to view_projection The uniform contains the view_projection matrix so this was incorrect. * bevy_pbr2: PointLight is an OmniLight as it has a radius * bevy_pbr2: Factoring out duplicated code * bevy_pbr2: Implement RenderAsset for StandardMaterial * Remove unnecessary texture and sampler clones * fix comment formatting * remove redundant Buffer:from * Don't extract meshes when their material textures aren't ready * make missing textures in the queue step an error Co-authored-by: Aevyrie <aevyrie@gmail.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2021-06-27 23:10:23 +00:00
[[example]]
name = "shadow_biases"
path = "examples/3d/shadow_biases.rs"
doc-scrape-examples = true
Scale normal bias by texel size (#26) * 3d_scene_pipelined: Use a shallower directional light angle to provoke acne * cornell_box_pipelined: Remove bias tweaks * bevy_pbr2: Simplify shadow biases by moving them to linear depth * bevy_pbr2: Do not use DepthBiasState * bevy_pbr2: Do not use bilinear filtering for sampling depth textures * pbr.wgsl: Remove unnecessary comment * bevy_pbr2: Do manual shadow map depth comparisons for more flexibility * examples: Add shadow_biases_pipelined example This is useful for stress testing biases. * bevy_pbr2: Scale the point light normal bias by the shadow map texel size This allows the normal bias to be small close to the light source where the shadow map texel to screen texel ratio is high, but is appropriately large further away from the light source where the shadow map texel can easily cover multiple screen texels. * shadow_biases_pipelined: Add support for toggling directional / point light * shadow_biases_pipelined: Cleanup * bevy_pbr2: Scale the directional light normal bias by the shadow map texel size * shadow_biases_pipelined: Fit the orthographic projection around the scene * bevy_pbr2: Directional lights should have no shadows outside their projection Before this change, sampling a fragment position from outside the ndc volume would result in the return sample being clamped to the edge in x,y or possibly always casting a shadow for fragment positions past the orthographic projection's far plane. * bevy_pbr2: Fix the default directional light normal bias * Revert "bevy_pbr2: Do manual shadow map depth comparisons for more flexibility" This reverts commit 7df1bab38a42d8a33bc50ca583d4be37bd9c9f0d. * shadow_biases_pipelined: Adjust directional light normal bias in 0.1 increments * pbr.wgsl: Add a couple of clarifying comments * Revert "bevy_pbr2: Do not use bilinear filtering for sampling depth textures" This reverts commit f53baab0232ce218866a45cad6902b470f4cf2c4. * shadow_biases_pipelined: Print usage to terminal
2021-07-19 19:20:59 +00:00
[package.metadata.example.shadow_biases]
name = "Shadow Biases"
description = "Demonstrates how shadow biases affect shadows in a 3d scene"
category = "3D Rendering"
wasm = true
[[example]]
name = "shadow_caster_receiver"
path = "examples/3d/shadow_caster_receiver.rs"
doc-scrape-examples = true
2020-05-01 20:12:47 +00:00
[package.metadata.example.shadow_caster_receiver]
name = "Shadow Caster and Receiver"
description = "Demonstrates how to prevent meshes from casting/receiving shadows in a 3d scene"
category = "3D Rendering"
wasm = true
Support array / cubemap / cubemap array textures in KTX2 (#5325) # Objective - Fix / support KTX2 array / cubemap / cubemap array textures - Fixes #4495 . Supersedes #4514 . ## Solution - Add `Option<TextureViewDescriptor>` to `Image` to enable configuration of the `TextureViewDimension` of a texture. - This allows users to set `D2Array`, `D3`, `Cube`, `CubeArray` or whatever they need - Automatically configure this when loading KTX2 - Transcode all layers and faces instead of just one - Use the UASTC block size of 128 bits, and the number of blocks in x/y for a given mip level in order to determine the offset of the layer and face within the KTX2 mip level data - `wgpu` wants data ordered as layer 0 mip 0..n, layer 1 mip 0..n, etc. See https://docs.rs/wgpu/latest/wgpu/util/trait.DeviceExt.html#tymethod.create_texture_with_data - Reorder the data KTX2 mip X layer Y face Z to `wgpu` layer Y face Z mip X order - Add a `skybox` example to demonstrate / test loading cubemaps from PNG and KTX2, including ASTC 4x4, BC7, and ETC2 compression for support everywhere. Note that you need to enable the `ktx2,zstd` features to be able to load the compressed textures. --- ## Changelog - Fixed: KTX2 array / cubemap / cubemap array textures - Fixes: Validation failure for compressed textures stored in KTX2 where the width/height are not a multiple of the block dimensions. - Added: `Image` now has an `Option<TextureViewDescriptor>` field to enable configuration of the texture view. This is useful for configuring the `TextureViewDimension` when it is not just a plain 2D texture and the loader could/did not identify what it should be. Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-07-30 07:02:58 +00:00
[[example]]
name = "skybox"
path = "examples/3d/skybox.rs"
doc-scrape-examples = true
Support array / cubemap / cubemap array textures in KTX2 (#5325) # Objective - Fix / support KTX2 array / cubemap / cubemap array textures - Fixes #4495 . Supersedes #4514 . ## Solution - Add `Option<TextureViewDescriptor>` to `Image` to enable configuration of the `TextureViewDimension` of a texture. - This allows users to set `D2Array`, `D3`, `Cube`, `CubeArray` or whatever they need - Automatically configure this when loading KTX2 - Transcode all layers and faces instead of just one - Use the UASTC block size of 128 bits, and the number of blocks in x/y for a given mip level in order to determine the offset of the layer and face within the KTX2 mip level data - `wgpu` wants data ordered as layer 0 mip 0..n, layer 1 mip 0..n, etc. See https://docs.rs/wgpu/latest/wgpu/util/trait.DeviceExt.html#tymethod.create_texture_with_data - Reorder the data KTX2 mip X layer Y face Z to `wgpu` layer Y face Z mip X order - Add a `skybox` example to demonstrate / test loading cubemaps from PNG and KTX2, including ASTC 4x4, BC7, and ETC2 compression for support everywhere. Note that you need to enable the `ktx2,zstd` features to be able to load the compressed textures. --- ## Changelog - Fixed: KTX2 array / cubemap / cubemap array textures - Fixes: Validation failure for compressed textures stored in KTX2 where the width/height are not a multiple of the block dimensions. - Added: `Image` now has an `Option<TextureViewDescriptor>` field to enable configuration of the texture view. This is useful for configuring the `TextureViewDimension` when it is not just a plain 2D texture and the loader could/did not identify what it should be. Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-07-30 07:02:58 +00:00
[package.metadata.example.skybox]
name = "Skybox"
description = "Load a cubemap texture onto a cube like a skybox and cycle through different compressed texture formats."
category = "3D Rendering"
wasm = false
[[example]]
name = "spherical_area_lights"
path = "examples/3d/spherical_area_lights.rs"
doc-scrape-examples = true
[package.metadata.example.spherical_area_lights]
name = "Spherical Area Lights"
description = "Demonstrates how point light radius values affect light behavior"
category = "3D Rendering"
wasm = true
Camera Driven Viewports (#4898) # Objective Users should be able to render cameras to specific areas of a render target, which enables scenarios like split screen, minimaps, etc. Builds on the new Camera Driven Rendering added here: #4745 Fixes: #202 Alternative to #1389 and #3626 (which are incompatible with the new Camera Driven Rendering) ## Solution ![image](https://user-images.githubusercontent.com/2694663/171560044-f0694f67-0cd9-4598-83e2-a9658c4fed57.png) Cameras can now configure an optional "viewport", which defines a rectangle within their render target to draw to. If a `Viewport` is defined, the camera's `CameraProjection`, `View`, and visibility calculations will use the viewport configuration instead of the full render target. ```rust // This camera will render to the first half of the primary window (on the left side). commands.spawn_bundle(Camera3dBundle { camera: Camera { viewport: Some(Viewport { physical_position: UVec2::new(0, 0), physical_size: UVec2::new(window.physical_width() / 2, window.physical_height()), depth: 0.0..1.0, }), ..default() }, ..default() }); ``` To account for this, the `Camera` component has received a few adjustments: * `Camera` now has some new getter functions: * `logical_viewport_size`, `physical_viewport_size`, `logical_target_size`, `physical_target_size`, `projection_matrix` * All computed camera values are now private and live on the `ComputedCameraValues` field (logical/physical width/height, the projection matrix). They are now exposed on `Camera` via getters/setters This wasn't _needed_ for viewports, but it was long overdue. --- ## Changelog ### Added * `Camera` components now have a `viewport` field, which can be set to draw to a portion of a render target instead of the full target. * `Camera` component has some new functions: `logical_viewport_size`, `physical_viewport_size`, `logical_target_size`, `physical_target_size`, and `projection_matrix` * Added a new split_screen example illustrating how to render two cameras to the same scene ## Migration Guide `Camera::projection_matrix` is no longer a public field. Use the new `Camera::projection_matrix()` method instead: ```rust // Bevy 0.7 let projection = camera.projection_matrix; // Bevy 0.8 let projection = camera.projection_matrix(); ```
2022-06-05 00:27:49 +00:00
[[example]]
name = "split_screen"
path = "examples/3d/split_screen.rs"
doc-scrape-examples = true
Camera Driven Viewports (#4898) # Objective Users should be able to render cameras to specific areas of a render target, which enables scenarios like split screen, minimaps, etc. Builds on the new Camera Driven Rendering added here: #4745 Fixes: #202 Alternative to #1389 and #3626 (which are incompatible with the new Camera Driven Rendering) ## Solution ![image](https://user-images.githubusercontent.com/2694663/171560044-f0694f67-0cd9-4598-83e2-a9658c4fed57.png) Cameras can now configure an optional "viewport", which defines a rectangle within their render target to draw to. If a `Viewport` is defined, the camera's `CameraProjection`, `View`, and visibility calculations will use the viewport configuration instead of the full render target. ```rust // This camera will render to the first half of the primary window (on the left side). commands.spawn_bundle(Camera3dBundle { camera: Camera { viewport: Some(Viewport { physical_position: UVec2::new(0, 0), physical_size: UVec2::new(window.physical_width() / 2, window.physical_height()), depth: 0.0..1.0, }), ..default() }, ..default() }); ``` To account for this, the `Camera` component has received a few adjustments: * `Camera` now has some new getter functions: * `logical_viewport_size`, `physical_viewport_size`, `logical_target_size`, `physical_target_size`, `projection_matrix` * All computed camera values are now private and live on the `ComputedCameraValues` field (logical/physical width/height, the projection matrix). They are now exposed on `Camera` via getters/setters This wasn't _needed_ for viewports, but it was long overdue. --- ## Changelog ### Added * `Camera` components now have a `viewport` field, which can be set to draw to a portion of a render target instead of the full target. * `Camera` component has some new functions: `logical_viewport_size`, `physical_viewport_size`, `logical_target_size`, `physical_target_size`, and `projection_matrix` * Added a new split_screen example illustrating how to render two cameras to the same scene ## Migration Guide `Camera::projection_matrix` is no longer a public field. Use the new `Camera::projection_matrix()` method instead: ```rust // Bevy 0.7 let projection = camera.projection_matrix; // Bevy 0.8 let projection = camera.projection_matrix(); ```
2022-06-05 00:27:49 +00:00
[package.metadata.example.split_screen]
name = "Split Screen"
description = "Demonstrates how to render two cameras to the same window to accomplish \"split screen\""
category = "3D Rendering"
wasm = true
2020-05-01 20:12:47 +00:00
[[example]]
name = "texture"
path = "examples/3d/texture.rs"
doc-scrape-examples = true
2020-05-01 20:12:47 +00:00
[package.metadata.example.texture]
name = "Texture"
description = "Shows configuration of texture materials"
category = "3D Rendering"
wasm = true
[[example]]
name = "transparency_3d"
path = "examples/3d/transparency_3d.rs"
doc-scrape-examples = true
[package.metadata.example.transparency_3d]
name = "Transparency in 3D"
description = "Demonstrates transparency in 3d"
category = "3D Rendering"
wasm = true
`StandardMaterial` Light Transmission (#8015) # Objective <img width="1920" alt="Screenshot 2023-04-26 at 01 07 34" src="https://user-images.githubusercontent.com/418473/234467578-0f34187b-5863-4ea1-88e9-7a6bb8ce8da3.png"> This PR adds both diffuse and specular light transmission capabilities to the `StandardMaterial`, with support for screen space refractions. This enables realistically representing a wide range of real-world materials, such as: - Glass; (Including frosted glass) - Transparent and translucent plastics; - Various liquids and gels; - Gemstones; - Marble; - Wax; - Paper; - Leaves; - Porcelain. Unlike existing support for transparency, light transmission does not rely on fixed function alpha blending, and therefore works with both `AlphaMode::Opaque` and `AlphaMode::Mask` materials. ## Solution - Introduces a number of transmission related fields in the `StandardMaterial`; - For specular transmission: - Adds logic to take a view main texture snapshot after the opaque phase; (in order to perform screen space refractions) - Introduces a new `Transmissive3d` phase to the renderer, to which all meshes with `transmission > 0.0` materials are sent. - Calculates a light exit point (of the approximate mesh volume) using `ior` and `thickness` properties - Samples the snapshot texture with an adaptive number of taps across a `roughness`-controlled radius enabling “blurry” refractions - For diffuse transmission: - Approximates transmitted diffuse light by using a second, flipped + displaced, diffuse-only Lambertian lobe for each light source. ## To Do - [x] Figure out where `fresnel_mix()` is taking place, if at all, and where `dielectric_specular` is being calculated, if at all, and update them to use the `ior` value (Not a blocker, just a nice-to-have for more correct BSDF) - To the _best of my knowledge, this is now taking place, after 964340cdd. The fresnel mix is actually "split" into two parts in our implementation, one `(1 - fresnel(...))` in the transmission, and `fresnel()` in the light implementations. A surface with more reflectance now will produce slightly dimmer transmission towards the grazing angle, as more of the light gets reflected. - [x] Add `transmission_texture` - [x] Add `diffuse_transmission_texture` - [x] Add `thickness_texture` - [x] Add `attenuation_distance` and `attenuation_color` - [x] Connect values to glTF loader - [x] `transmission` and `transmission_texture` - [x] `thickness` and `thickness_texture` - [x] `ior` - [ ] `diffuse_transmission` and `diffuse_transmission_texture` (needs upstream support in `gltf` crate, not a blocker) - [x] Add support for multiple screen space refraction “steps” - [x] Conditionally create no transmission snapshot texture at all if `steps == 0` - [x] Conditionally enable/disable screen space refraction transmission snapshots - [x] Read from depth pre-pass to prevent refracting pixels in front of the light exit point - [x] Use `interleaved_gradient_noise()` function for sampling blur in a way that benefits from TAA - [x] Drill down a TAA `#define`, tweak some aspects of the effect conditionally based on it - [x] Remove const array that's crashing under HLSL (unless a new `naga` release with https://github.com/gfx-rs/naga/pull/2496 comes out before we merge this) - [ ] Look into alternatives to the `switch` hack for dynamically indexing the const array (might not be needed, compilers seem to be decent at expanding it) - [ ] Add pipeline keys for gating transmission (do we really want/need this?) - [x] Tweak some material field/function names? ## A Note on Texture Packing _This was originally added as a comment to the `specular_transmission_texture`, `thickness_texture` and `diffuse_transmission_texture` documentation, I removed it since it was more confusing than helpful, and will likely be made redundant/will need to be updated once we have a better infrastructure for preprocessing assets_ Due to how channels are mapped, you can more efficiently use a single shared texture image for configuring the following: - R - `specular_transmission_texture` - G - `thickness_texture` - B - _unused_ - A - `diffuse_transmission_texture` The `KHR_materials_diffuse_transmission` glTF extension also defines a `diffuseTransmissionColorTexture`, that _we don't currently support_. One might choose to pack the intensity and color textures together, using RGB for the color and A for the intensity, in which case this packing advice doesn't really apply. --- ## Changelog - Added a new `Transmissive3d` render phase for rendering specular transmissive materials with screen space refractions - Added rendering support for transmitted environment map light on the `StandardMaterial` as a fallback for screen space refractions - Added `diffuse_transmission`, `specular_transmission`, `thickness`, `ior`, `attenuation_distance` and `attenuation_color` to the `StandardMaterial` - Added `diffuse_transmission_texture`, `specular_transmission_texture`, `thickness_texture` to the `StandardMaterial`, gated behind a new `pbr_transmission_textures` cargo feature (off by default, for maximum hardware compatibility) - Added `Camera3d::screen_space_specular_transmission_steps` for controlling the number of “layers of transparency” rendered for transmissive objects - Added a `TransmittedShadowReceiver` component for enabling shadows in (diffusely) transmitted light. (disabled by default, as it requires carefully setting up the `thickness` to avoid self-shadow artifacts) - Added support for the `KHR_materials_transmission`, `KHR_materials_ior` and `KHR_materials_volume` glTF extensions - Renamed items related to temporal jitter for greater consistency ## Migration Guide - `SsaoPipelineKey::temporal_noise` has been renamed to `SsaoPipelineKey::temporal_jitter` - The `TAA` shader def (controlled by the presence of the `TemporalAntiAliasSettings` component in the camera) has been replaced with the `TEMPORAL_JITTER` shader def (controlled by the presence of the `TemporalJitter` component in the camera) - `MeshPipelineKey::TAA` has been replaced by `MeshPipelineKey::TEMPORAL_JITTER` - The `TEMPORAL_NOISE` shader def has been consolidated with `TEMPORAL_JITTER`
2023-10-31 20:59:02 +00:00
[[example]]
name = "transmission"
path = "examples/3d/transmission.rs"
[package.metadata.example.transmission]
name = "Transmission"
description = "Showcases light transmission in the PBR material"
category = "3D Rendering"
wasm = true
[[example]]
name = "two_passes"
path = "examples/3d/two_passes.rs"
doc-scrape-examples = true
[package.metadata.example.two_passes]
name = "Two Passes"
description = "Renders two 3d passes to the same window from different perspectives"
category = "3D Rendering"
wasm = true
[[example]]
name = "update_gltf_scene"
path = "examples/3d/update_gltf_scene.rs"
doc-scrape-examples = true
[package.metadata.example.update_gltf_scene]
name = "Update glTF Scene"
description = "Update a scene from a glTF file, either by spawning the scene as a child of another entity, or by accessing the entities of the scene"
category = "3D Rendering"
wasm = true
[[example]]
name = "vertex_colors"
path = "examples/3d/vertex_colors.rs"
doc-scrape-examples = true
[package.metadata.example.vertex_colors]
name = "Vertex Colors"
description = "Shows the use of vertex colors"
category = "3D Rendering"
wasm = true
[[example]]
name = "wireframe"
path = "examples/3d/wireframe.rs"
doc-scrape-examples = true
[package.metadata.example.wireframe]
name = "Wireframe"
description = "Showcases wireframe rendering"
category = "3D Rendering"
wasm = false
[[example]]
name = "no_prepass"
path = "tests/3d/no_prepass.rs"
doc-scrape-examples = true
[package.metadata.example.no_prepass]
hidden = true
# Animation
[[example]]
name = "animated_fox"
path = "examples/animation/animated_fox.rs"
doc-scrape-examples = true
[package.metadata.example.animated_fox]
name = "Animated Fox"
description = "Plays an animation from a skinned glTF"
category = "Animation"
wasm = true
Add morph targets (#8158) # Objective - Add morph targets to `bevy_pbr` (closes #5756) & load them from glTF - Supersedes #3722 - Fixes #6814 [Morph targets][1] (also known as shape interpolation, shape keys, or blend shapes) allow animating individual vertices with fine grained controls. This is typically used for facial expressions. By specifying multiple poses as vertex offset, and providing a set of weight of each pose, it is possible to define surprisingly realistic transitions between poses. Blending between multiple poses also allow composition. Morph targets are part of the [gltf standard][2] and are a feature of Unity and Unreal, and babylone.js, it is only natural to implement them in bevy. ## Solution This implementation of morph targets uses a 3d texture where each pixel is a component of an animated attribute. Each layer is a different target. We use a 2d texture for each target, because the number of attribute×components×animated vertices is expected to always exceed the maximum pixel row size limit of webGL2. It copies fairly closely the way skinning is implemented on the CPU side, while on the GPU side, the shader morph target implementation is a relatively trivial detail. We add an optional `morph_texture` to the `Mesh` struct. The `morph_texture` is built through a method that accepts an iterator over attribute buffers. The `MorphWeights` component, user-accessible, controls the blend of poses used by mesh instances (so that multiple copy of the same mesh may have different weights), all the weights are uploaded to a uniform buffer of 256 `f32`. We limit to 16 poses per mesh, and a total of 256 poses. More literature: * Old babylone.js implementation (vertex attribute-based): https://www.eternalcoding.com/dev-log-1-morph-targets/ * Babylone.js implementation (similar to ours): https://www.youtube.com/watch?v=LBPRmGgU0PE * GPU gems 3: https://developer.nvidia.com/gpugems/gpugems3/part-i-geometry/chapter-3-directx-10-blend-shapes-breaking-limits * Development discord thread https://discord.com/channels/691052431525675048/1083325980615114772 https://user-images.githubusercontent.com/26321040/231181046-3bca2ab2-d4d9-472e-8098-639f1871ce2e.mp4 https://github.com/bevyengine/bevy/assets/26321040/d2a0c544-0ef8-45cf-9f99-8c3792f5a258 ## Acknowledgements * Thanks to `storytold` for sponsoring the feature * Thanks to `superdump` and `james7132` for guidance and help figuring out stuff ## Future work - Handling of less and more attributes (eg: animated uv, animated arbitrary attributes) - Dynamic pose allocation (so that zero-weighted poses aren't uploaded to GPU for example, enables much more total poses) - Better animation API, see #8357 ---- ## Changelog - Add morph targets to bevy meshes - Support up to 64 poses per mesh of individually up to 116508 vertices, animation currently strictly limited to the position, normal and tangent attributes. - Load a morph target using `Mesh::set_morph_targets` - Add `VisitMorphTargets` and `VisitMorphAttributes` traits to `bevy_render`, this allows defining morph targets (a fairly complex and nested data structure) through iterators (ie: single copy instead of passing around buffers), see documentation of those traits for details - Add `MorphWeights` component exported by `bevy_render` - `MorphWeights` control mesh's morph target weights, blending between various poses defined as morph targets. - `MorphWeights` are directly inherited by direct children (single level of hierarchy) of an entity. This allows controlling several mesh primitives through a unique entity _as per GLTF spec_. - Add `MorphTargetNames` component, naming each indices of loaded morph targets. - Load morph targets weights and buffers in `bevy_gltf` - handle morph targets animations in `bevy_animation` (previously, it was a `warn!` log) - Add the `MorphStressTest.gltf` asset for morph targets testing, taken from the glTF samples repo, CC0. - Add morph target manipulation to `scene_viewer` - Separate the animation code in `scene_viewer` from the rest of the code, reducing `#[cfg(feature)]` noise - Add the `morph_targets.rs` example to show off how to manipulate morph targets, loading `MorpStressTest.gltf` ## Migration Guide - (very specialized, unlikely to be touched by 3rd parties) - `MeshPipeline` now has a single `mesh_layouts` field rather than separate `mesh_layout` and `skinned_mesh_layout` fields. You should handle all possible mesh bind group layouts in your implementation - You should also handle properly the new `MORPH_TARGETS` shader def and mesh pipeline key. A new function is exposed to make this easier: `setup_moprh_and_skinning_defs` - The `MeshBindGroup` is now `MeshBindGroups`, cached bind groups are now accessed through the `get` method. [1]: https://en.wikipedia.org/wiki/Morph_target_animation [2]: https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#morph-targets --------- Co-authored-by: François <mockersf@gmail.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2023-06-22 20:00:01 +00:00
[[example]]
name = "morph_targets"
path = "examples/animation/morph_targets.rs"
doc-scrape-examples = true
Add morph targets (#8158) # Objective - Add morph targets to `bevy_pbr` (closes #5756) & load them from glTF - Supersedes #3722 - Fixes #6814 [Morph targets][1] (also known as shape interpolation, shape keys, or blend shapes) allow animating individual vertices with fine grained controls. This is typically used for facial expressions. By specifying multiple poses as vertex offset, and providing a set of weight of each pose, it is possible to define surprisingly realistic transitions between poses. Blending between multiple poses also allow composition. Morph targets are part of the [gltf standard][2] and are a feature of Unity and Unreal, and babylone.js, it is only natural to implement them in bevy. ## Solution This implementation of morph targets uses a 3d texture where each pixel is a component of an animated attribute. Each layer is a different target. We use a 2d texture for each target, because the number of attribute×components×animated vertices is expected to always exceed the maximum pixel row size limit of webGL2. It copies fairly closely the way skinning is implemented on the CPU side, while on the GPU side, the shader morph target implementation is a relatively trivial detail. We add an optional `morph_texture` to the `Mesh` struct. The `morph_texture` is built through a method that accepts an iterator over attribute buffers. The `MorphWeights` component, user-accessible, controls the blend of poses used by mesh instances (so that multiple copy of the same mesh may have different weights), all the weights are uploaded to a uniform buffer of 256 `f32`. We limit to 16 poses per mesh, and a total of 256 poses. More literature: * Old babylone.js implementation (vertex attribute-based): https://www.eternalcoding.com/dev-log-1-morph-targets/ * Babylone.js implementation (similar to ours): https://www.youtube.com/watch?v=LBPRmGgU0PE * GPU gems 3: https://developer.nvidia.com/gpugems/gpugems3/part-i-geometry/chapter-3-directx-10-blend-shapes-breaking-limits * Development discord thread https://discord.com/channels/691052431525675048/1083325980615114772 https://user-images.githubusercontent.com/26321040/231181046-3bca2ab2-d4d9-472e-8098-639f1871ce2e.mp4 https://github.com/bevyengine/bevy/assets/26321040/d2a0c544-0ef8-45cf-9f99-8c3792f5a258 ## Acknowledgements * Thanks to `storytold` for sponsoring the feature * Thanks to `superdump` and `james7132` for guidance and help figuring out stuff ## Future work - Handling of less and more attributes (eg: animated uv, animated arbitrary attributes) - Dynamic pose allocation (so that zero-weighted poses aren't uploaded to GPU for example, enables much more total poses) - Better animation API, see #8357 ---- ## Changelog - Add morph targets to bevy meshes - Support up to 64 poses per mesh of individually up to 116508 vertices, animation currently strictly limited to the position, normal and tangent attributes. - Load a morph target using `Mesh::set_morph_targets` - Add `VisitMorphTargets` and `VisitMorphAttributes` traits to `bevy_render`, this allows defining morph targets (a fairly complex and nested data structure) through iterators (ie: single copy instead of passing around buffers), see documentation of those traits for details - Add `MorphWeights` component exported by `bevy_render` - `MorphWeights` control mesh's morph target weights, blending between various poses defined as morph targets. - `MorphWeights` are directly inherited by direct children (single level of hierarchy) of an entity. This allows controlling several mesh primitives through a unique entity _as per GLTF spec_. - Add `MorphTargetNames` component, naming each indices of loaded morph targets. - Load morph targets weights and buffers in `bevy_gltf` - handle morph targets animations in `bevy_animation` (previously, it was a `warn!` log) - Add the `MorphStressTest.gltf` asset for morph targets testing, taken from the glTF samples repo, CC0. - Add morph target manipulation to `scene_viewer` - Separate the animation code in `scene_viewer` from the rest of the code, reducing `#[cfg(feature)]` noise - Add the `morph_targets.rs` example to show off how to manipulate morph targets, loading `MorpStressTest.gltf` ## Migration Guide - (very specialized, unlikely to be touched by 3rd parties) - `MeshPipeline` now has a single `mesh_layouts` field rather than separate `mesh_layout` and `skinned_mesh_layout` fields. You should handle all possible mesh bind group layouts in your implementation - You should also handle properly the new `MORPH_TARGETS` shader def and mesh pipeline key. A new function is exposed to make this easier: `setup_moprh_and_skinning_defs` - The `MeshBindGroup` is now `MeshBindGroups`, cached bind groups are now accessed through the `get` method. [1]: https://en.wikipedia.org/wiki/Morph_target_animation [2]: https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#morph-targets --------- Co-authored-by: François <mockersf@gmail.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2023-06-22 20:00:01 +00:00
[package.metadata.example.morph_targets]
name = "Morph Targets"
description = "Plays an animation from a glTF file with meshes with morph targets"
category = "Animation"
wasm = true
[[example]]
name = "animated_transform"
path = "examples/animation/animated_transform.rs"
doc-scrape-examples = true
[package.metadata.example.animated_transform]
name = "Animated Transform"
description = "Create and play an animation defined by code that operates on the `Transform` component"
category = "Animation"
wasm = true
[[example]]
name = "cubic_curve"
path = "examples/animation/cubic_curve.rs"
doc-scrape-examples = true
[package.metadata.example.cubic_curve]
name = "Cubic Curve"
description = "Bezier curve example showing a cube following a cubic curve"
category = "Animation"
wasm = true
[[example]]
name = "custom_skinned_mesh"
path = "examples/animation/custom_skinned_mesh.rs"
doc-scrape-examples = true
[package.metadata.example.custom_skinned_mesh]
name = "Custom Skinned Mesh"
description = "Skinned mesh example with mesh and joints data defined in code"
category = "Animation"
wasm = true
[[example]]
name = "gltf_skinned_mesh"
path = "examples/animation/gltf_skinned_mesh.rs"
doc-scrape-examples = true
[package.metadata.example.gltf_skinned_mesh]
name = "glTF Skinned Mesh"
description = "Skinned mesh example with mesh and joints data loaded from a glTF file"
category = "Animation"
wasm = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
# Application
[[example]]
name = "custom_loop"
path = "examples/app/custom_loop.rs"
doc-scrape-examples = true
[package.metadata.example.custom_loop]
name = "Custom Loop"
description = "Demonstrates how to create a custom runner (to update an app manually)"
category = "Application"
wasm = false
[[example]]
name = "drag_and_drop"
path = "examples/app/drag_and_drop.rs"
doc-scrape-examples = true
[package.metadata.example.drag_and_drop]
name = "Drag and Drop"
description = "An example that shows how to handle drag and drop in an app"
category = "Application"
wasm = false
2020-05-01 20:12:47 +00:00
[[example]]
name = "empty"
path = "examples/app/empty.rs"
doc-scrape-examples = true
2020-05-01 20:12:47 +00:00
[package.metadata.example.empty]
name = "Empty"
description = "An empty application (does nothing)"
category = "Application"
wasm = false
2020-11-13 01:23:57 +00:00
[[example]]
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
name = "empty_defaults"
path = "examples/app/empty_defaults.rs"
doc-scrape-examples = true
2020-11-13 01:23:57 +00:00
[package.metadata.example.empty_defaults]
name = "Empty with Defaults"
description = "An empty application with default plugins"
category = "Application"
wasm = true
2020-05-01 20:12:47 +00:00
[[example]]
name = "headless"
path = "examples/app/headless.rs"
doc-scrape-examples = true
2020-05-01 20:12:47 +00:00
[package.metadata.example.headless]
name = "Headless"
description = "An application that runs without default plugins"
category = "Application"
wasm = false
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[[example]]
name = "logs"
path = "examples/app/logs.rs"
doc-scrape-examples = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[package.metadata.example.logs]
name = "Logs"
description = "Illustrate how to use generate log output"
category = "Application"
wasm = true
2020-05-03 08:30:10 +00:00
[[example]]
name = "plugin"
path = "examples/app/plugin.rs"
doc-scrape-examples = true
2020-05-03 08:30:10 +00:00
[package.metadata.example.plugin]
name = "Plugin"
description = "Demonstrates the creation and registration of a custom plugin"
category = "Application"
wasm = true
[[example]]
name = "plugin_group"
path = "examples/app/plugin_group.rs"
doc-scrape-examples = true
[package.metadata.example.plugin_group]
name = "Plugin Group"
description = "Demonstrates the creation and registration of a custom plugin group"
category = "Application"
wasm = true
[[example]]
name = "return_after_run"
path = "examples/app/return_after_run.rs"
doc-scrape-examples = true
[package.metadata.example.return_after_run]
name = "Return after Run"
description = "Show how to return to main after the Bevy app has exited"
category = "Application"
wasm = false
[[example]]
name = "thread_pool_resources"
path = "examples/app/thread_pool_resources.rs"
doc-scrape-examples = true
[package.metadata.example.thread_pool_resources]
name = "Thread Pool Resources"
description = "Creates and customizes the internal thread pool"
category = "Application"
wasm = false
[[example]]
name = "no_renderer"
path = "examples/app/no_renderer.rs"
doc-scrape-examples = true
[package.metadata.example.no_renderer]
name = "No Renderer"
description = "An application that runs with default plugins and displays an empty window, but without an actual renderer"
category = "Application"
wasm = false
[[example]]
name = "without_winit"
path = "examples/app/without_winit.rs"
doc-scrape-examples = true
[package.metadata.example.without_winit]
name = "Without Winit"
description = "Create an application without winit (runs single time, no event loop)"
category = "Application"
wasm = false
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
# Assets
2020-05-17 03:18:30 +00:00
[[example]]
name = "asset_loading"
path = "examples/asset/asset_loading.rs"
doc-scrape-examples = true
2020-05-17 03:18:30 +00:00
[package.metadata.example.asset_loading]
name = "Asset Loading"
description = "Demonstrates various methods to load assets"
category = "Assets"
wasm = false
[[example]]
name = "custom_asset"
path = "examples/asset/custom_asset.rs"
doc-scrape-examples = true
[package.metadata.example.custom_asset]
name = "Custom Asset"
description = "Implements a custom asset loader"
category = "Assets"
wasm = true
[[example]]
Bevy Asset V2 (#8624) # Bevy Asset V2 Proposal ## Why Does Bevy Need A New Asset System? Asset pipelines are a central part of the gamedev process. Bevy's current asset system is missing a number of features that make it non-viable for many classes of gamedev. After plenty of discussions and [a long community feedback period](https://github.com/bevyengine/bevy/discussions/3972), we've identified a number missing features: * **Asset Preprocessing**: it should be possible to "preprocess" / "compile" / "crunch" assets at "development time" rather than when the game starts up. This enables offloading expensive work from deployed apps, faster asset loading, less runtime memory usage, etc. * **Per-Asset Loader Settings**: Individual assets cannot define their own loaders that override the defaults. Additionally, they cannot provide per-asset settings to their loaders. This is a huge limitation, as many asset types don't provide all information necessary for Bevy _inside_ the asset. For example, a raw PNG image says nothing about how it should be sampled (ex: linear vs nearest). * **Asset `.meta` files**: assets should have configuration files stored adjacent to the asset in question, which allows the user to configure asset-type-specific settings. These settings should be accessible during the pre-processing phase. Modifying a `.meta` file should trigger a re-processing / re-load of the asset. It should be possible to configure asset loaders from the meta file. * **Processed Asset Hot Reloading**: Changes to processed assets (or their dependencies) should result in re-processing them and re-loading the results in live Bevy Apps. * **Asset Dependency Tracking**: The current bevy_asset has no good way to wait for asset dependencies to load. It punts this as an exercise for consumers of the loader apis, which is unreasonable and error prone. There should be easy, ergonomic ways to wait for assets to load and block some logic on an asset's entire dependency tree loading. * **Runtime Asset Loading**: it should be (optionally) possible to load arbitrary assets dynamically at runtime. This necessitates being able to deploy and run the asset server alongside Bevy Apps on _all platforms_. For example, we should be able to invoke the shader compiler at runtime, stream scenes from sources like the internet, etc. To keep deployed binaries (and startup times) small, the runtime asset server configuration should be configurable with different settings compared to the "pre processor asset server". * **Multiple Backends**: It should be possible to load assets from arbitrary sources (filesystems, the internet, remote asset serves, etc). * **Asset Packing**: It should be possible to deploy assets in compressed "packs", which makes it easier and more efficient to distribute assets with Bevy Apps. * **Asset Handoff**: It should be possible to hold a "live" asset handle, which correlates to runtime data, without actually holding the asset in memory. Ex: it must be possible to hold a reference to a GPU mesh generated from a "mesh asset" without keeping the mesh data in CPU memory * **Per-Platform Processed Assets**: Different platforms and app distributions have different capabilities and requirements. Some platforms need lower asset resolutions or different asset formats to operate within the hardware constraints of the platform. It should be possible to define per-platform asset processing profiles. And it should be possible to deploy only the assets required for a given platform. These features have architectural implications that are significant enough to require a full rewrite. The current Bevy Asset implementation got us this far, but it can take us no farther. This PR defines a brand new asset system that implements most of these features, while laying the foundations for the remaining features to be built. ## Bevy Asset V2 Here is a quick overview of the features introduced in this PR. * **Asset Preprocessing**: Preprocess assets at development time into more efficient (and configurable) representations * **Dependency Aware**: Dependencies required to process an asset are tracked. If an asset's processed dependency changes, it will be reprocessed * **Hot Reprocessing/Reloading**: detect changes to asset source files, reprocess them if they have changed, and then hot-reload them in Bevy Apps. * **Only Process Changes**: Assets are only re-processed when their source file (or meta file) has changed. This uses hashing and timestamps to avoid processing assets that haven't changed. * **Transactional and Reliable**: Uses write-ahead logging (a technique commonly used by databases) to recover from crashes / forced-exits. Whenever possible it avoids full-reprocessing / only uncompleted transactions will be reprocessed. When the processor is running in parallel with a Bevy App, processor asset writes block Bevy App asset reads. Reading metadata + asset bytes is guaranteed to be transactional / correctly paired. * **Portable / Run anywhere / Database-free**: The processor does not rely on an in-memory database (although it uses some database techniques for reliability). This is important because pretty much all in-memory databases have unsupported platforms or build complications. * **Configure Processor Defaults Per File Type**: You can say "use this processor for all files of this type". * **Custom Processors**: The `Processor` trait is flexible and unopinionated. It can be implemented by downstream plugins. * **LoadAndSave Processors**: Most asset processing scenarios can be expressed as "run AssetLoader A, save the results using AssetSaver X, and then load the result using AssetLoader B". For example, load this png image using `PngImageLoader`, which produces an `Image` asset and then save it using `CompressedImageSaver` (which also produces an `Image` asset, but in a compressed format), which takes an `Image` asset as input. This means if you have an `AssetLoader` for an asset, you are already half way there! It also means that you can share AssetSavers across multiple loaders. Because `CompressedImageSaver` accepts Bevy's generic Image asset as input, it means you can also use it with some future `JpegImageLoader`. * **Loader and Saver Settings**: Asset Loaders and Savers can now define their own settings types, which are passed in as input when an asset is loaded / saved. Each asset can define its own settings. * **Asset `.meta` files**: configure asset loaders, their settings, enable/disable processing, and configure processor settings * **Runtime Asset Dependency Tracking** Runtime asset dependencies (ex: if an asset contains a `Handle<Image>`) are tracked by the asset server. An event is emitted when an asset and all of its dependencies have been loaded * **Unprocessed Asset Loading**: Assets do not require preprocessing. They can be loaded directly. A processed asset is just a "normal" asset with some extra metadata. Asset Loaders don't need to know or care about whether or not an asset was processed. * **Async Asset IO**: Asset readers/writers use async non-blocking interfaces. Note that because Rust doesn't yet support async traits, there is a bit of manual Boxing / Future boilerplate. This will hopefully be removed in the near future when Rust gets async traits. * **Pluggable Asset Readers and Writers**: Arbitrary asset source readers/writers are supported, both by the processor and the asset server. * **Better Asset Handles** * **Single Arc Tree**: Asset Handles now use a single arc tree that represents the lifetime of the asset. This makes their implementation simpler, more efficient, and allows us to cheaply attach metadata to handles. Ex: the AssetPath of a handle is now directly accessible on the handle itself! * **Const Typed Handles**: typed handles can be constructed in a const context. No more weird "const untyped converted to typed at runtime" patterns! * **Handles and Ids are Smaller / Faster To Hash / Compare**: Typed `Handle<T>` is now much smaller in memory and `AssetId<T>` is even smaller. * **Weak Handle Usage Reduction**: In general Handles are now considered to be "strong". Bevy features that previously used "weak `Handle<T>`" have been ported to `AssetId<T>`, which makes it statically clear that the features do not hold strong handles (while retaining strong type information). Currently Handle::Weak still exists, but it is very possible that we can remove that entirely. * **Efficient / Dense Asset Ids**: Assets now have efficient dense runtime asset ids, which means we can avoid expensive hash lookups. Assets are stored in Vecs instead of HashMaps. There are now typed and untyped ids, which means we no longer need to store dynamic type information in the ID for typed handles. "AssetPathId" (which was a nightmare from a performance and correctness standpoint) has been entirely removed in favor of dense ids (which are retrieved for a path on load) * **Direct Asset Loading, with Dependency Tracking**: Assets that are defined at runtime can still have their dependencies tracked by the Asset Server (ex: if you create a material at runtime, you can still wait for its textures to load). This is accomplished via the (currently optional) "asset dependency visitor" trait. This system can also be used to define a set of assets to load, then wait for those assets to load. * **Async folder loading**: Folder loading also uses this system and immediately returns a handle to the LoadedFolder asset, which means folder loading no longer blocks on directory traversals. * **Improved Loader Interface**: Loaders now have a specific "top level asset type", which makes returning the top-level asset simpler and statically typed. * **Basic Image Settings and Processing**: Image assets can now be processed into the gpu-friendly Basic Universal format. The ImageLoader now has a setting to define what format the image should be loaded as. Note that this is just a minimal MVP ... plenty of additional work to do here. To demo this, enable the `basis-universal` feature and turn on asset processing. * **Simpler Audio Play / AudioSink API**: Asset handle providers are cloneable, which means the Audio resource can mint its own handles. This means you can now do `let sink_handle = audio.play(music)` instead of `let sink_handle = audio_sinks.get_handle(audio.play(music))`. Note that this might still be replaced by https://github.com/bevyengine/bevy/pull/8424. **Removed Handle Casting From Engine Features**: Ex: FontAtlases no longer use casting between handle types ## Using The New Asset System ### Normal Unprocessed Asset Loading By default the `AssetPlugin` does not use processing. It behaves pretty much the same way as the old system. If you are defining a custom asset, first derive `Asset`: ```rust #[derive(Asset)] struct Thing { value: String, } ``` Initialize the asset: ```rust app.init_asset:<Thing>() ``` Implement a new `AssetLoader` for it: ```rust #[derive(Default)] struct ThingLoader; #[derive(Serialize, Deserialize, Default)] pub struct ThingSettings { some_setting: bool, } impl AssetLoader for ThingLoader { type Asset = Thing; type Settings = ThingSettings; fn load<'a>( &'a self, reader: &'a mut Reader, settings: &'a ThingSettings, load_context: &'a mut LoadContext, ) -> BoxedFuture<'a, Result<Thing, anyhow::Error>> { Box::pin(async move { let mut bytes = Vec::new(); reader.read_to_end(&mut bytes).await?; // convert bytes to value somehow Ok(Thing { value }) }) } fn extensions(&self) -> &[&str] { &["thing"] } } ``` Note that this interface will get much cleaner once Rust gets support for async traits. `Reader` is an async futures_io::AsyncRead. You can stream bytes as they come in or read them all into a `Vec<u8>`, depending on the context. You can use `let handle = load_context.load(path)` to kick off a dependency load, retrieve a handle, and register the dependency for the asset. Then just register the loader in your Bevy app: ```rust app.init_asset_loader::<ThingLoader>() ``` Now just add your `Thing` asset files into the `assets` folder and load them like this: ```rust fn system(asset_server: Res<AssetServer>) { let handle = Handle<Thing> = asset_server.load("cool.thing"); } ``` You can check load states directly via the asset server: ```rust if asset_server.load_state(&handle) == LoadState::Loaded { } ``` You can also listen for events: ```rust fn system(mut events: EventReader<AssetEvent<Thing>>, handle: Res<SomeThingHandle>) { for event in events.iter() { if event.is_loaded_with_dependencies(&handle) { } } } ``` Note the new `AssetEvent::LoadedWithDependencies`, which only fires when the asset is loaded _and_ all dependencies (and their dependencies) have loaded. Unlike the old asset system, for a given asset path all `Handle<T>` values point to the same underlying Arc. This means Handles can cheaply hold more asset information, such as the AssetPath: ```rust // prints the AssetPath of the handle info!("{:?}", handle.path()) ``` ### Processed Assets Asset processing can be enabled via the `AssetPlugin`. When developing Bevy Apps with processed assets, do this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev())) ``` This runs the `AssetProcessor` in the background with hot-reloading. It reads assets from the `assets` folder, processes them, and writes them to the `.imported_assets` folder. Asset loads in the Bevy App will wait for a processed version of the asset to become available. If an asset in the `assets` folder changes, it will be reprocessed and hot-reloaded in the Bevy App. When deploying processed Bevy apps, do this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::processed())) ``` This does not run the `AssetProcessor` in the background. It behaves like `AssetPlugin::unprocessed()`, but reads assets from `.imported_assets`. When the `AssetProcessor` is running, it will populate sibling `.meta` files for assets in the `assets` folder. Meta files for assets that do not have a processor configured look like this: ```rust ( meta_format_version: "1.0", asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: FromExtension, ), ), ) ``` This is metadata for an image asset. For example, if you have `assets/my_sprite.png`, this could be the metadata stored at `assets/my_sprite.png.meta`. Meta files are totally optional. If no metadata exists, the default settings will be used. In short, this file says "load this asset with the ImageLoader and use the file extension to determine the image type". This type of meta file is supported in all AssetPlugin modes. If in `Unprocessed` mode, the asset (with the meta settings) will be loaded directly. If in `ProcessedDev` mode, the asset file will be copied directly to the `.imported_assets` folder. The meta will also be copied directly to the `.imported_assets` folder, but with one addition: ```rust ( meta_format_version: "1.0", processed_info: Some(( hash: 12415480888597742505, full_hash: 14344495437905856884, process_dependencies: [], )), asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: FromExtension, ), ), ) ``` `processed_info` contains `hash` (a direct hash of the asset and meta bytes), `full_hash` (a hash of `hash` and the hashes of all `process_dependencies`), and `process_dependencies` (the `path` and `full_hash` of every process_dependency). A "process dependency" is an asset dependency that is _directly_ used when processing the asset. Images do not have process dependencies, so this is empty. When the processor is enabled, you can use the `Process` metadata config: ```rust ( meta_format_version: "1.0", asset: Process( processor: "bevy_asset::processor::process::LoadAndSave<bevy_render::texture::image_loader::ImageLoader, bevy_render::texture::compressed_image_saver::CompressedImageSaver>", settings: ( loader_settings: ( format: FromExtension, ), saver_settings: ( generate_mipmaps: true, ), ), ), ) ``` This configures the asset to use the `LoadAndSave` processor, which runs an AssetLoader and feeds the result into an AssetSaver (which saves the given Asset and defines a loader to load it with). (for terseness LoadAndSave will likely get a shorter/friendlier type name when [Stable Type Paths](#7184) lands). `LoadAndSave` is likely to be the most common processor type, but arbitrary processors are supported. `CompressedImageSaver` saves an `Image` in the Basis Universal format and configures the ImageLoader to load it as basis universal. The `AssetProcessor` will read this meta, run it through the LoadAndSave processor, and write the basis-universal version of the image to `.imported_assets`. The final metadata will look like this: ```rust ( meta_format_version: "1.0", processed_info: Some(( hash: 905599590923828066, full_hash: 9948823010183819117, process_dependencies: [], )), asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: Format(Basis), ), ), ) ``` To try basis-universal processing out in Bevy examples, (for example `sprite.rs`), change `add_plugins(DefaultPlugins)` to `add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev()))` and run with the `basis-universal` feature enabled: `cargo run --features=basis-universal --example sprite`. To create a custom processor, there are two main paths: 1. Use the `LoadAndSave` processor with an existing `AssetLoader`. Implement the `AssetSaver` trait, register the processor using `asset_processor.register_processor::<LoadAndSave<ImageLoader, CompressedImageSaver>>(image_saver.into())`. 2. Implement the `Process` trait directly and register it using: `asset_processor.register_processor(thing_processor)`. You can configure default processors for file extensions like this: ```rust asset_processor.set_default_processor::<ThingProcessor>("thing") ``` There is one more metadata type to be aware of: ```rust ( meta_format_version: "1.0", asset: Ignore, ) ``` This will ignore the asset during processing / prevent it from being written to `.imported_assets`. The AssetProcessor stores a transaction log at `.imported_assets/log` and uses it to gracefully recover from unexpected stops. This means you can force-quit the processor (and Bevy Apps running the processor in parallel) at arbitrary times! `.imported_assets` is "local state". It should _not_ be checked into source control. It should also be considered "read only". In practice, you _can_ modify processed assets and processed metadata if you really need to test something. But those modifications will not be represented in the hashes of the assets, so the processed state will be "out of sync" with the source assets. The processor _will not_ fix this for you. Either revert the change after you have tested it, or delete the processed files so they can be re-populated. ## Open Questions There are a number of open questions to be discussed. We should decide if they need to be addressed in this PR and if so, how we will address them: ### Implied Dependencies vs Dependency Enumeration There are currently two ways to populate asset dependencies: * **Implied via AssetLoaders**: if an AssetLoader loads an asset (and retrieves a handle), a dependency is added to the list. * **Explicit via the optional Asset::visit_dependencies**: if `server.load_asset(my_asset)` is called, it will call `my_asset.visit_dependencies`, which will grab dependencies that have been manually defined for the asset via the Asset trait impl (which can be derived). This means that defining explicit dependencies is optional for "loaded assets". And the list of dependencies is always accurate because loaders can only produce Handles if they register dependencies. If an asset was loaded with an AssetLoader, it only uses the implied dependencies. If an asset was created at runtime and added with `asset_server.load_asset(MyAsset)`, it will use `Asset::visit_dependencies`. However this can create a behavior mismatch between loaded assets and equivalent "created at runtime" assets if `Assets::visit_dependencies` doesn't exactly match the dependencies produced by the AssetLoader. This behavior mismatch can be resolved by completely removing "implied loader dependencies" and requiring `Asset::visit_dependencies` to supply dependency data. But this creates two problems: * It makes defining loaded assets harder and more error prone: Devs must remember to manually annotate asset dependencies with `#[dependency]` when deriving `Asset`. For more complicated assets (such as scenes), the derive likely wouldn't be sufficient and a manual `visit_dependencies` impl would be required. * Removes the ability to immediately kick off dependency loads: When AssetLoaders retrieve a Handle, they also immediately kick off an asset load for the handle, which means it can start loading in parallel _before_ the asset finishes loading. For large assets, this could be significant. (although this could be mitigated for processed assets if we store dependencies in the processed meta file and load them ahead of time) ### Eager ProcessorDev Asset Loading I made a controversial call in the interest of fast startup times ("time to first pixel") for the "processor dev mode configuration". When initializing the AssetProcessor, current processed versions of unchanged assets are yielded immediately, even if their dependencies haven't been checked yet for reprocessing. This means that non-current-state-of-filesystem-but-previously-valid assets might be returned to the App first, then hot-reloaded if/when their dependencies change and the asset is reprocessed. Is this behavior desirable? There is largely one alternative: do not yield an asset from the processor to the app until all of its dependencies have been checked for changes. In some common cases (load dependency has not changed since last run) this will increase startup time. The main question is "by how much" and is that slower startup time worth it in the interest of only yielding assets that are true to the current state of the filesystem. Should this be configurable? I'm starting to think we should only yield an asset after its (historical) dependencies have been checked for changes + processed as necessary, but I'm curious what you all think. ### Paths Are Currently The Only Canonical ID / Do We Want Asset UUIDs? In this implementation AssetPaths are the only canonical asset identifier (just like the previous Bevy Asset system and Godot). Moving assets will result in re-scans (and currently reprocessing, although reprocessing can easily be avoided with some changes). Asset renames/moves will break code and assets that rely on specific paths, unless those paths are fixed up. Do we want / need "stable asset uuids"? Introducing them is very possible: 1. Generate a UUID and include it in .meta files 2. Support UUID in AssetPath 3. Generate "asset indices" which are loaded on startup and map UUIDs to paths. 4 (maybe). Consider only supporting UUIDs for processed assets so we can generate quick-to-load indices instead of scanning meta files. The main "pro" is that assets referencing UUIDs don't need to be migrated when a path changes. The main "con" is that UUIDs cannot be "lazily resolved" like paths. They need a full view of all assets to answer the question "does this UUID exist". Which means UUIDs require the AssetProcessor to fully finish startup scans before saying an asset doesnt exist. And they essentially require asset pre-processing to use in apps, because scanning all asset metadata files at runtime to resolve a UUID is not viable for medium-to-large apps. It really requires a pre-generated UUID index, which must be loaded before querying for assets. I personally think this should be investigated in a separate PR. Paths aren't going anywhere ... _everyone_ uses filesystems (and filesystem-like apis) to manage their asset source files. I consider them permanent canonical asset information. Additionally, they behave well for both processed and unprocessed asset modes. Given that Bevy is supporting both, this feels like the right canonical ID to start with. UUIDS (and maybe even other indexed-identifier types) can be added later as necessary. ### Folder / File Naming Conventions All asset processing config currently lives in the `.imported_assets` folder. The processor transaction log is in `.imported_assets/log`. Processed assets are added to `.imported_assets/Default`, which will make migrating to processed asset profiles (ex: a `.imported_assets/Mobile` profile) a non-breaking change. It also allows us to create top-level files like `.imported_assets/log` without it being interpreted as an asset. Meta files currently have a `.meta` suffix. Do we like these names and conventions? ### Should the `AssetPlugin::processed_dev` configuration enable `watch_for_changes` automatically? Currently it does (which I think makes sense), but it does make it the only configuration that enables watch_for_changes by default. ### Discuss on_loaded High Level Interface: This PR includes a very rough "proof of concept" `on_loaded` system adapter that uses the `LoadedWithDependencies` event in combination with `asset_server.load_asset` dependency tracking to support this pattern ```rust fn main() { App::new() .init_asset::<MyAssets>() .add_systems(Update, on_loaded(create_array_texture)) .run(); } #[derive(Asset, Clone)] struct MyAssets { #[dependency] picture_of_my_cat: Handle<Image>, #[dependency] picture_of_my_other_cat: Handle<Image>, } impl FromWorld for ArrayTexture { fn from_world(world: &mut World) -> Self { picture_of_my_cat: server.load("meow.png"), picture_of_my_other_cat: server.load("meeeeeeeow.png"), } } fn spawn_cat(In(my_assets): In<MyAssets>, mut commands: Commands) { commands.spawn(SpriteBundle { texture: my_assets.picture_of_my_cat.clone(), ..default() }); commands.spawn(SpriteBundle { texture: my_assets.picture_of_my_other_cat.clone(), ..default() }); } ``` The implementation is _very_ rough. And it is currently unsafe because `bevy_ecs` doesn't expose some internals to do this safely from inside `bevy_asset`. There are plenty of unanswered questions like: * "do we add a Loadable" derive? (effectively automate the FromWorld implementation above) * Should `MyAssets` even be an Asset? (largely implemented this way because it elegantly builds on `server.load_asset(MyAsset { .. })` dependency tracking). We should think hard about what our ideal API looks like (and if this is a pattern we want to support). Not necessarily something we need to solve in this PR. The current `on_loaded` impl should probably be removed from this PR before merging. ## Clarifying Questions ### What about Assets as Entities? This Bevy Asset V2 proposal implementation initially stored Assets as ECS Entities. Instead of `AssetId<T>` + the `Assets<T>` resource it used `Entity` as the asset id and Asset values were just ECS components. There are plenty of compelling reasons to do this: 1. Easier to inline assets in Bevy Scenes (as they are "just" normal entities + components) 2. More flexible queries: use the power of the ECS to filter assets (ex: `Query<Mesh, With<Tree>>`). 3. Extensible. Users can add arbitrary component data to assets. 4. Things like "component visualization tools" work out of the box to visualize asset data. However Assets as Entities has a ton of caveats right now: * We need to be able to allocate entity ids without a direct World reference (aka rework id allocator in Entities ... i worked around this in my prototypes by just pre allocating big chunks of entities) * We want asset change events in addition to ECS change tracking ... how do we populate them when mutations can come from anywhere? Do we use Changed queries? This would require iterating over the change data for all assets every frame. Is this acceptable or should we implement a new "event based" component change detection option? * Reconciling manually created assets with asset-system managed assets has some nuance (ex: are they "loaded" / do they also have that component metadata?) * "how do we handle "static" / default entity handles" (ties in to the Entity Indices discussion: https://github.com/bevyengine/bevy/discussions/8319). This is necessary for things like "built in" assets and default handles in things like SpriteBundle. * Storing asset information as a component makes it easy to "invalidate" asset state by removing the component (or forcing modifications). Ideally we have ways to lock this down (some combination of Rust type privacy and ECS validation) In practice, how we store and identify assets is a reasonably superficial change (porting off of Assets as Entities and implementing dedicated storage + ids took less than a day). So once we sort out the remaining challenges the flip should be straightforward. Additionally, I do still have "Assets as Entities" in my commit history, so we can reuse that work. I personally think "assets as entities" is a good endgame, but it also doesn't provide _significant_ value at the moment and it certainly isn't ready yet with the current state of things. ### Why not Distill? [Distill](https://github.com/amethyst/distill) is a high quality fully featured asset system built in Rust. It is very natural to ask "why not just use Distill?". It is also worth calling out that for awhile, [we planned on adopting Distill / I signed off on it](https://github.com/bevyengine/bevy/issues/708). However I think Bevy has a number of constraints that make Distill adoption suboptimal: * **Architectural Simplicity:** * Distill's processor requires an in-memory database (lmdb) and RPC networked API (using Cap'n Proto). Each of these introduces API complexity that increases maintenance burden and "code grokability". Ignoring tests, documentation, and examples, Distill has 24,237 lines of Rust code (including generated code for RPC + database interactions). If you ignore generated code, it has 11,499 lines. * Bevy builds the AssetProcessor and AssetServer using pluggable AssetReader/AssetWriter Rust traits with simple io interfaces. They do not necessitate databases or RPC interfaces (although Readers/Writers could use them if that is desired). Bevy Asset V2 (at the time of writing this PR) is 5,384 lines of Rust code (ignoring tests, documentation, and examples). Grain of salt: Distill does have more features currently (ex: Asset Packing, GUIDS, remote-out-of-process asset processor). I do plan to implement these features in Bevy Asset V2 and I personally highly doubt they will meaningfully close the 6115 lines-of-code gap. * This complexity gap (which while illustrated by lines of code, is much bigger than just that) is noteworthy to me. Bevy should be hackable and there are pillars of Distill that are very hard to understand and extend. This is a matter of opinion (and Bevy Asset V2 also has complicated areas), but I think Bevy Asset V2 is much more approachable for the average developer. * Necessary disclaimer: counting lines of code is an extremely rough complexity metric. Read the code and form your own opinions. * **Optional Asset Processing:** Not all Bevy Apps (or Bevy App developers) need / want asset preprocessing. Processing increases the complexity of the development environment by introducing things like meta files, imported asset storage, running processors in the background, waiting for processing to finish, etc. Distill _requires_ preprocessing to work. With Bevy Asset V2 processing is fully opt-in. The AssetServer isn't directly aware of asset processors at all. AssetLoaders only care about converting bytes to runtime Assets ... they don't know or care if the bytes were pre-processed or not. Processing is "elegantly" (forgive my self-congratulatory phrasing) layered on top and builds on the existing Asset system primitives. * **Direct Filesystem Access to Processed Asset State:** Distill stores processed assets in a database. This makes debugging / inspecting the processed outputs harder (either requires special tooling to query the database or they need to be "deployed" to be inspected). Bevy Asset V2, on the other hand, stores processed assets in the filesystem (by default ... this is configurable). This makes interacting with the processed state more natural. Note that both Godot and Unity's new asset system store processed assets in the filesystem. * **Portability**: Because Distill's processor uses lmdb and RPC networking, it cannot be run on certain platforms (ex: lmdb is a non-rust dependency that cannot run on the web, some platforms don't support running network servers). Bevy should be able to process assets everywhere (ex: run the Bevy Editor on the web, compile + process shaders on mobile, etc). Distill does partially mitigate this problem by supporting "streaming" assets via the RPC protocol, but this is not a full solve from my perspective. And Bevy Asset V2 can (in theory) also stream assets (without requiring RPC, although this isn't implemented yet) Note that I _do_ still think Distill would be a solid asset system for Bevy. But I think the approach in this PR is a better solve for Bevy's specific "asset system requirements". ### Doesn't async-fs just shim requests to "sync" `std::fs`? What is the point? "True async file io" has limited / spotty platform support. async-fs (and the rust async ecosystem generally ... ex Tokio) currently use async wrappers over std::fs that offload blocking requests to separate threads. This may feel unsatisfying, but it _does_ still provide value because it prevents our task pools from blocking on file system operations (which would prevent progress when there are many tasks to do, but all threads in a pool are currently blocking on file system ops). Additionally, using async APIs for our AssetReaders and AssetWriters also provides value because we can later add support for "true async file io" for platforms that support it. _And_ we can implement other "true async io" asset backends (such as networked asset io). ## Draft TODO - [x] Fill in missing filesystem event APIs: file removed event (which is expressed as dangling RenameFrom events in some cases), file/folder renamed event - [x] Assets without loaders are not moved to the processed folder. This breaks things like referenced `.bin` files for GLTFs. This should be configurable per-non-asset-type. - [x] Initial implementation of Reflect and FromReflect for Handle. The "deserialization" parity bar is low here as this only worked with static UUIDs in the old impl ... this is a non-trivial problem. Either we add a Handle::AssetPath variant that gets "upgraded" to a strong handle on scene load or we use a separate AssetRef type for Bevy scenes (which is converted to a runtime Handle on load). This deserves its own discussion in a different pr. - [x] Populate read_asset_bytes hash when run by the processor (a bit of a special case .. when run by the processor the processed meta will contain the hash so we don't need to compute it on the spot, but we don't want/need to read the meta when run by the main AssetServer) - [x] Delay hot reloading: currently filesystem events are handled immediately, which creates timing issues in some cases. For example hot reloading images can sometimes break because the image isn't finished writing. We should add a delay, likely similar to the [implementation in this PR](https://github.com/bevyengine/bevy/pull/8503). - [x] Port old platform-specific AssetIo implementations to the new AssetReader interface (currently missing Android and web) - [x] Resolve on_loaded unsafety (either by removing the API entirely or removing the unsafe) - [x] Runtime loader setting overrides - [x] Remove remaining unwraps that should be error-handled. There are number of TODOs here - [x] Pretty AssetPath Display impl - [x] Document more APIs - [x] Resolve spurious "reloading because it has changed" events (to repro run load_gltf with `processed_dev()`) - [x] load_dependency hot reloading currently only works for processed assets. If processing is disabled, load_dependency changes are not hot reloaded. - [x] Replace AssetInfo dependency load/fail counters with `loading_dependencies: HashSet<UntypedAssetId>` to prevent reloads from (potentially) breaking counters. Storing this will also enable "dependency reloaded" events (see [Next Steps](#next-steps)) - [x] Re-add filesystem watcher cargo feature gate (currently it is not optional) - [ ] Migration Guide - [ ] Changelog ## Followup TODO - [ ] Replace "eager unchanged processed asset loading" behavior with "don't returned unchanged processed asset until dependencies have been checked". - [ ] Add true `Ignore` AssetAction that does not copy the asset to the imported_assets folder. - [ ] Finish "live asset unloading" (ex: free up CPU asset memory after uploading an image to the GPU), rethink RenderAssets, and port renderer features. The `Assets` collection uses `Option<T>` for asset storage to support its removal. (1) the Option might not actually be necessary ... might be able to just remove from the collection entirely (2) need to finalize removal apis - [ ] Try replacing the "channel based" asset id recycling with something a bit more efficient (ex: we might be able to use raw atomic ints with some cleverness) - [ ] Consider adding UUIDs to processed assets (scoped just to helping identify moved assets ... not exposed to load queries ... see [Next Steps](#next-steps)) - [ ] Store "last modified" source asset and meta timestamps in processed meta files to enable skipping expensive hashing when the file wasn't changed - [ ] Fix "slow loop" handle drop fix - [ ] Migrate to TypeName - [x] Handle "loader preregistration". See #9429 ## Next Steps * **Configurable per-type defaults for AssetMeta**: It should be possible to add configuration like "all png image meta should default to using nearest sampling" (currently this hard-coded per-loader/processor Settings::default() impls). Also see the "Folder Meta" bullet point. * **Avoid Reprocessing on Asset Renames / Moves**: See the "canonical asset ids" discussion in [Open Questions](#open-questions) and the relevant bullet point in [Draft TODO](#draft-todo). Even without canonical ids, folder renames could avoid reprocessing in some cases. * **Multiple Asset Sources**: Expand AssetPath to support "asset source names" and support multiple AssetReaders in the asset server (ex: `webserver://some_path/image.png` backed by an Http webserver AssetReader). The "default" asset reader would use normal `some_path/image.png` paths. Ideally this works in combination with multiple AssetWatchers for hot-reloading * **Stable Type Names**: this pr removes the TypeUuid requirement from assets in favor of `std::any::type_name`. This makes defining assets easier (no need to generate a new uuid / use weird proc macro syntax). It also makes reading meta files easier (because things have "friendly names"). We also use type names for components in scene files. If they are good enough for components, they are good enough for assets. And consistency across Bevy pillars is desirable. However, `std::any::type_name` is not guaranteed to be stable (although in practice it is). We've developed a [stable type path](https://github.com/bevyengine/bevy/pull/7184) to resolve this, which should be adopted when it is ready. * **Command Line Interface**: It should be possible to run the asset processor in a separate process from the command line. This will also require building a network-server-backed AssetReader to communicate between the app and the processor. We've been planning to build a "bevy cli" for awhile. This seems like a good excuse to build it. * **Asset Packing**: This is largely an additive feature, so it made sense to me to punt this until we've laid the foundations in this PR. * **Per-Platform Processed Assets**: It should be possible to generate assets for multiple platforms by supporting multiple "processor profiles" per asset (ex: compress with format X on PC and Y on iOS). I think there should probably be arbitrary "profiles" (which can be separate from actual platforms), which are then assigned to a given platform when generating the final asset distribution for that platform. Ex: maybe devs want a "Mobile" profile that is shared between iOS and Android. Or a "LowEnd" profile shared between web and mobile. * **Versioning and Migrations**: Assets, Loaders, Savers, and Processors need to have versions to determine if their schema is valid. If an asset / loader version is incompatible with the current version expected at runtime, the processor should be able to migrate them. I think we should try using Bevy Reflect for this, as it would allow us to load the old version as a dynamic Reflect type without actually having the old Rust type. It would also allow us to define "patches" to migrate between versions (Bevy Reflect devs are currently working on patching). The `.meta` file already has its own format version. Migrating that to new versions should also be possible. * **Real Copy-on-write AssetPaths**: Rust's actual Cow (clone-on-write type) currently used by AssetPath can still result in String clones that aren't actually necessary (cloning an Owned Cow clones the contents). Bevy's asset system requires cloning AssetPaths in a number of places, which result in actual clones of the internal Strings. This is not efficient. AssetPath internals should be reworked to exhibit truer cow-like-behavior that reduces String clones to the absolute minimum. * **Consider processor-less processing**: In theory the AssetServer could run processors "inline" even if the background AssetProcessor is disabled. If we decide this is actually desirable, we could add this. But I don't think its a priority in the short or medium term. * **Pre-emptive dependency loading**: We could encode dependencies in processed meta files, which could then be used by the Asset Server to kick of dependency loads as early as possible (prior to starting the actual asset load). Is this desirable? How much time would this save in practice? * **Optimize Processor With UntypedAssetIds**: The processor exclusively uses AssetPath to identify assets currently. It might be possible to swap these out for UntypedAssetIds in some places, which are smaller / cheaper to hash and compare. * **One to Many Asset Processing**: An asset source file that produces many assets currently must be processed into a single "processed" asset source. If labeled assets can be written separately they can each have their own configured savers _and_ they could be loaded more granularly. Definitely worth exploring! * **Automatically Track "Runtime-only" Asset Dependencies**: Right now, tracking "created at runtime" asset dependencies requires adding them via `asset_server.load_asset(StandardMaterial::default())`. I think with some cleverness we could also do this for `materials.add(StandardMaterial::default())`, making tracking work "everywhere". There are challenges here relating to change detection / ensuring the server is made aware of dependency changes. This could be expensive in some cases. * **"Dependency Changed" events**: Some assets have runtime artifacts that need to be re-generated when one of their dependencies change (ex: regenerate a material's bind group when a Texture needs to change). We are generating the dependency graph so we can definitely produce these events. Buuuuut generating these events will have a cost / they could be high frequency for some assets, so we might want this to be opt-in for specific cases. * **Investigate Storing More Information In Handles**: Handles can now store arbitrary information, which makes it cheaper and easier to access. How much should we move into them? Canonical asset load states (via atomics)? (`handle.is_loaded()` would be very cool). Should we store the entire asset and remove the `Assets<T>` collection? (`Arc<RwLock<Option<Image>>>`?) * **Support processing and loading files without extensions**: This is a pretty arbitrary restriction and could be supported with very minimal changes. * **Folder Meta**: It would be nice if we could define per folder processor configuration defaults (likely in a `.meta` or `.folder_meta` file). Things like "default to linear filtering for all Images in this folder". * **Replace async_broadcast with event-listener?** This might be approximately drop-in for some uses and it feels more light weight * **Support Running the AssetProcessor on the Web**: Most of the hard work is done here, but there are some easy straggling TODOs (make the transaction log an interface instead of a direct file writer so we can write a web storage backend, implement an AssetReader/AssetWriter that reads/writes to something like LocalStorage). * **Consider identifying and preventing circular dependencies**: This is especially important for "processor dependencies", as processing will silently never finish in these cases. * **Built-in/Inlined Asset Hot Reloading**: This PR regresses "built-in/inlined" asset hot reloading (previously provided by the DebugAssetServer). I'm intentionally punting this because I think it can be cleanly implemented with "multiple asset sources" by registering a "debug asset source" (ex: `debug://bevy_pbr/src/render/pbr.wgsl` asset paths) in combination with an AssetWatcher for that asset source and support for "manually loading pats with asset bytes instead of AssetReaders". The old DebugAssetServer was quite nasty and I'd love to avoid that hackery going forward. * **Investigate ways to remove double-parsing meta files**: Parsing meta files currently involves parsing once with "minimal" versions of the meta file to extract the type name of the loader/processor config, then parsing again to parse the "full" meta. This is suboptimal. We should be able to define custom deserializers that (1) assume the loader/processor type name comes first (2) dynamically looks up the loader/processor registrations to deserialize settings in-line (similar to components in the bevy scene format). Another alternative: deserialize as dynamic Reflect objects and then convert. * **More runtime loading configuration**: Support using the Handle type as a hint to select an asset loader (instead of relying on AssetPath extensions) * **More high level Processor trait implementations**: For example, it might be worth adding support for arbitrary chains of "asset transforms" that modify an in-memory asset representation between loading and saving. (ex: load a Mesh, run a `subdivide_mesh` transform, followed by a `flip_normals` transform, then save the mesh to an efficient compressed format). * **Bevy Scene Handle Deserialization**: (see the relevant [Draft TODO item](#draft-todo) for context) * **Explore High Level Load Interfaces**: See [this discussion](#discuss-on_loaded-high-level-interface) for one prototype. * **Asset Streaming**: It would be great if we could stream Assets (ex: stream a long video file piece by piece) * **ID Exchanging**: In this PR Asset Handles/AssetIds are bigger than they need to be because they have a Uuid enum variant. If we implement an "id exchanging" system that trades Uuids for "efficient runtime ids", we can cut down on the size of AssetIds, making them more efficient. This has some open design questions, such as how to spawn entities with "default" handle values (as these wouldn't have access to the exchange api in the current system). * **Asset Path Fixup Tooling**: Assets that inline asset paths inside them will break when an asset moves. The asset system provides the functionality to detect when paths break. We should build a framework that enables formats to define "path migrations". This is especially important for scene files. For editor-generated files, we should also consider using UUIDs (see other bullet point) to avoid the need to migrate in these cases. --------- Co-authored-by: BeastLe9enD <beastle9end@outlook.de> Co-authored-by: Mike <mike.hsu@gmail.com> Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com>
2023-09-07 02:07:27 +00:00
name = "custom_asset_reader"
path = "examples/asset/custom_asset_reader.rs"
doc-scrape-examples = true
Bevy Asset V2 (#8624) # Bevy Asset V2 Proposal ## Why Does Bevy Need A New Asset System? Asset pipelines are a central part of the gamedev process. Bevy's current asset system is missing a number of features that make it non-viable for many classes of gamedev. After plenty of discussions and [a long community feedback period](https://github.com/bevyengine/bevy/discussions/3972), we've identified a number missing features: * **Asset Preprocessing**: it should be possible to "preprocess" / "compile" / "crunch" assets at "development time" rather than when the game starts up. This enables offloading expensive work from deployed apps, faster asset loading, less runtime memory usage, etc. * **Per-Asset Loader Settings**: Individual assets cannot define their own loaders that override the defaults. Additionally, they cannot provide per-asset settings to their loaders. This is a huge limitation, as many asset types don't provide all information necessary for Bevy _inside_ the asset. For example, a raw PNG image says nothing about how it should be sampled (ex: linear vs nearest). * **Asset `.meta` files**: assets should have configuration files stored adjacent to the asset in question, which allows the user to configure asset-type-specific settings. These settings should be accessible during the pre-processing phase. Modifying a `.meta` file should trigger a re-processing / re-load of the asset. It should be possible to configure asset loaders from the meta file. * **Processed Asset Hot Reloading**: Changes to processed assets (or their dependencies) should result in re-processing them and re-loading the results in live Bevy Apps. * **Asset Dependency Tracking**: The current bevy_asset has no good way to wait for asset dependencies to load. It punts this as an exercise for consumers of the loader apis, which is unreasonable and error prone. There should be easy, ergonomic ways to wait for assets to load and block some logic on an asset's entire dependency tree loading. * **Runtime Asset Loading**: it should be (optionally) possible to load arbitrary assets dynamically at runtime. This necessitates being able to deploy and run the asset server alongside Bevy Apps on _all platforms_. For example, we should be able to invoke the shader compiler at runtime, stream scenes from sources like the internet, etc. To keep deployed binaries (and startup times) small, the runtime asset server configuration should be configurable with different settings compared to the "pre processor asset server". * **Multiple Backends**: It should be possible to load assets from arbitrary sources (filesystems, the internet, remote asset serves, etc). * **Asset Packing**: It should be possible to deploy assets in compressed "packs", which makes it easier and more efficient to distribute assets with Bevy Apps. * **Asset Handoff**: It should be possible to hold a "live" asset handle, which correlates to runtime data, without actually holding the asset in memory. Ex: it must be possible to hold a reference to a GPU mesh generated from a "mesh asset" without keeping the mesh data in CPU memory * **Per-Platform Processed Assets**: Different platforms and app distributions have different capabilities and requirements. Some platforms need lower asset resolutions or different asset formats to operate within the hardware constraints of the platform. It should be possible to define per-platform asset processing profiles. And it should be possible to deploy only the assets required for a given platform. These features have architectural implications that are significant enough to require a full rewrite. The current Bevy Asset implementation got us this far, but it can take us no farther. This PR defines a brand new asset system that implements most of these features, while laying the foundations for the remaining features to be built. ## Bevy Asset V2 Here is a quick overview of the features introduced in this PR. * **Asset Preprocessing**: Preprocess assets at development time into more efficient (and configurable) representations * **Dependency Aware**: Dependencies required to process an asset are tracked. If an asset's processed dependency changes, it will be reprocessed * **Hot Reprocessing/Reloading**: detect changes to asset source files, reprocess them if they have changed, and then hot-reload them in Bevy Apps. * **Only Process Changes**: Assets are only re-processed when their source file (or meta file) has changed. This uses hashing and timestamps to avoid processing assets that haven't changed. * **Transactional and Reliable**: Uses write-ahead logging (a technique commonly used by databases) to recover from crashes / forced-exits. Whenever possible it avoids full-reprocessing / only uncompleted transactions will be reprocessed. When the processor is running in parallel with a Bevy App, processor asset writes block Bevy App asset reads. Reading metadata + asset bytes is guaranteed to be transactional / correctly paired. * **Portable / Run anywhere / Database-free**: The processor does not rely on an in-memory database (although it uses some database techniques for reliability). This is important because pretty much all in-memory databases have unsupported platforms or build complications. * **Configure Processor Defaults Per File Type**: You can say "use this processor for all files of this type". * **Custom Processors**: The `Processor` trait is flexible and unopinionated. It can be implemented by downstream plugins. * **LoadAndSave Processors**: Most asset processing scenarios can be expressed as "run AssetLoader A, save the results using AssetSaver X, and then load the result using AssetLoader B". For example, load this png image using `PngImageLoader`, which produces an `Image` asset and then save it using `CompressedImageSaver` (which also produces an `Image` asset, but in a compressed format), which takes an `Image` asset as input. This means if you have an `AssetLoader` for an asset, you are already half way there! It also means that you can share AssetSavers across multiple loaders. Because `CompressedImageSaver` accepts Bevy's generic Image asset as input, it means you can also use it with some future `JpegImageLoader`. * **Loader and Saver Settings**: Asset Loaders and Savers can now define their own settings types, which are passed in as input when an asset is loaded / saved. Each asset can define its own settings. * **Asset `.meta` files**: configure asset loaders, their settings, enable/disable processing, and configure processor settings * **Runtime Asset Dependency Tracking** Runtime asset dependencies (ex: if an asset contains a `Handle<Image>`) are tracked by the asset server. An event is emitted when an asset and all of its dependencies have been loaded * **Unprocessed Asset Loading**: Assets do not require preprocessing. They can be loaded directly. A processed asset is just a "normal" asset with some extra metadata. Asset Loaders don't need to know or care about whether or not an asset was processed. * **Async Asset IO**: Asset readers/writers use async non-blocking interfaces. Note that because Rust doesn't yet support async traits, there is a bit of manual Boxing / Future boilerplate. This will hopefully be removed in the near future when Rust gets async traits. * **Pluggable Asset Readers and Writers**: Arbitrary asset source readers/writers are supported, both by the processor and the asset server. * **Better Asset Handles** * **Single Arc Tree**: Asset Handles now use a single arc tree that represents the lifetime of the asset. This makes their implementation simpler, more efficient, and allows us to cheaply attach metadata to handles. Ex: the AssetPath of a handle is now directly accessible on the handle itself! * **Const Typed Handles**: typed handles can be constructed in a const context. No more weird "const untyped converted to typed at runtime" patterns! * **Handles and Ids are Smaller / Faster To Hash / Compare**: Typed `Handle<T>` is now much smaller in memory and `AssetId<T>` is even smaller. * **Weak Handle Usage Reduction**: In general Handles are now considered to be "strong". Bevy features that previously used "weak `Handle<T>`" have been ported to `AssetId<T>`, which makes it statically clear that the features do not hold strong handles (while retaining strong type information). Currently Handle::Weak still exists, but it is very possible that we can remove that entirely. * **Efficient / Dense Asset Ids**: Assets now have efficient dense runtime asset ids, which means we can avoid expensive hash lookups. Assets are stored in Vecs instead of HashMaps. There are now typed and untyped ids, which means we no longer need to store dynamic type information in the ID for typed handles. "AssetPathId" (which was a nightmare from a performance and correctness standpoint) has been entirely removed in favor of dense ids (which are retrieved for a path on load) * **Direct Asset Loading, with Dependency Tracking**: Assets that are defined at runtime can still have their dependencies tracked by the Asset Server (ex: if you create a material at runtime, you can still wait for its textures to load). This is accomplished via the (currently optional) "asset dependency visitor" trait. This system can also be used to define a set of assets to load, then wait for those assets to load. * **Async folder loading**: Folder loading also uses this system and immediately returns a handle to the LoadedFolder asset, which means folder loading no longer blocks on directory traversals. * **Improved Loader Interface**: Loaders now have a specific "top level asset type", which makes returning the top-level asset simpler and statically typed. * **Basic Image Settings and Processing**: Image assets can now be processed into the gpu-friendly Basic Universal format. The ImageLoader now has a setting to define what format the image should be loaded as. Note that this is just a minimal MVP ... plenty of additional work to do here. To demo this, enable the `basis-universal` feature and turn on asset processing. * **Simpler Audio Play / AudioSink API**: Asset handle providers are cloneable, which means the Audio resource can mint its own handles. This means you can now do `let sink_handle = audio.play(music)` instead of `let sink_handle = audio_sinks.get_handle(audio.play(music))`. Note that this might still be replaced by https://github.com/bevyengine/bevy/pull/8424. **Removed Handle Casting From Engine Features**: Ex: FontAtlases no longer use casting between handle types ## Using The New Asset System ### Normal Unprocessed Asset Loading By default the `AssetPlugin` does not use processing. It behaves pretty much the same way as the old system. If you are defining a custom asset, first derive `Asset`: ```rust #[derive(Asset)] struct Thing { value: String, } ``` Initialize the asset: ```rust app.init_asset:<Thing>() ``` Implement a new `AssetLoader` for it: ```rust #[derive(Default)] struct ThingLoader; #[derive(Serialize, Deserialize, Default)] pub struct ThingSettings { some_setting: bool, } impl AssetLoader for ThingLoader { type Asset = Thing; type Settings = ThingSettings; fn load<'a>( &'a self, reader: &'a mut Reader, settings: &'a ThingSettings, load_context: &'a mut LoadContext, ) -> BoxedFuture<'a, Result<Thing, anyhow::Error>> { Box::pin(async move { let mut bytes = Vec::new(); reader.read_to_end(&mut bytes).await?; // convert bytes to value somehow Ok(Thing { value }) }) } fn extensions(&self) -> &[&str] { &["thing"] } } ``` Note that this interface will get much cleaner once Rust gets support for async traits. `Reader` is an async futures_io::AsyncRead. You can stream bytes as they come in or read them all into a `Vec<u8>`, depending on the context. You can use `let handle = load_context.load(path)` to kick off a dependency load, retrieve a handle, and register the dependency for the asset. Then just register the loader in your Bevy app: ```rust app.init_asset_loader::<ThingLoader>() ``` Now just add your `Thing` asset files into the `assets` folder and load them like this: ```rust fn system(asset_server: Res<AssetServer>) { let handle = Handle<Thing> = asset_server.load("cool.thing"); } ``` You can check load states directly via the asset server: ```rust if asset_server.load_state(&handle) == LoadState::Loaded { } ``` You can also listen for events: ```rust fn system(mut events: EventReader<AssetEvent<Thing>>, handle: Res<SomeThingHandle>) { for event in events.iter() { if event.is_loaded_with_dependencies(&handle) { } } } ``` Note the new `AssetEvent::LoadedWithDependencies`, which only fires when the asset is loaded _and_ all dependencies (and their dependencies) have loaded. Unlike the old asset system, for a given asset path all `Handle<T>` values point to the same underlying Arc. This means Handles can cheaply hold more asset information, such as the AssetPath: ```rust // prints the AssetPath of the handle info!("{:?}", handle.path()) ``` ### Processed Assets Asset processing can be enabled via the `AssetPlugin`. When developing Bevy Apps with processed assets, do this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev())) ``` This runs the `AssetProcessor` in the background with hot-reloading. It reads assets from the `assets` folder, processes them, and writes them to the `.imported_assets` folder. Asset loads in the Bevy App will wait for a processed version of the asset to become available. If an asset in the `assets` folder changes, it will be reprocessed and hot-reloaded in the Bevy App. When deploying processed Bevy apps, do this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::processed())) ``` This does not run the `AssetProcessor` in the background. It behaves like `AssetPlugin::unprocessed()`, but reads assets from `.imported_assets`. When the `AssetProcessor` is running, it will populate sibling `.meta` files for assets in the `assets` folder. Meta files for assets that do not have a processor configured look like this: ```rust ( meta_format_version: "1.0", asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: FromExtension, ), ), ) ``` This is metadata for an image asset. For example, if you have `assets/my_sprite.png`, this could be the metadata stored at `assets/my_sprite.png.meta`. Meta files are totally optional. If no metadata exists, the default settings will be used. In short, this file says "load this asset with the ImageLoader and use the file extension to determine the image type". This type of meta file is supported in all AssetPlugin modes. If in `Unprocessed` mode, the asset (with the meta settings) will be loaded directly. If in `ProcessedDev` mode, the asset file will be copied directly to the `.imported_assets` folder. The meta will also be copied directly to the `.imported_assets` folder, but with one addition: ```rust ( meta_format_version: "1.0", processed_info: Some(( hash: 12415480888597742505, full_hash: 14344495437905856884, process_dependencies: [], )), asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: FromExtension, ), ), ) ``` `processed_info` contains `hash` (a direct hash of the asset and meta bytes), `full_hash` (a hash of `hash` and the hashes of all `process_dependencies`), and `process_dependencies` (the `path` and `full_hash` of every process_dependency). A "process dependency" is an asset dependency that is _directly_ used when processing the asset. Images do not have process dependencies, so this is empty. When the processor is enabled, you can use the `Process` metadata config: ```rust ( meta_format_version: "1.0", asset: Process( processor: "bevy_asset::processor::process::LoadAndSave<bevy_render::texture::image_loader::ImageLoader, bevy_render::texture::compressed_image_saver::CompressedImageSaver>", settings: ( loader_settings: ( format: FromExtension, ), saver_settings: ( generate_mipmaps: true, ), ), ), ) ``` This configures the asset to use the `LoadAndSave` processor, which runs an AssetLoader and feeds the result into an AssetSaver (which saves the given Asset and defines a loader to load it with). (for terseness LoadAndSave will likely get a shorter/friendlier type name when [Stable Type Paths](#7184) lands). `LoadAndSave` is likely to be the most common processor type, but arbitrary processors are supported. `CompressedImageSaver` saves an `Image` in the Basis Universal format and configures the ImageLoader to load it as basis universal. The `AssetProcessor` will read this meta, run it through the LoadAndSave processor, and write the basis-universal version of the image to `.imported_assets`. The final metadata will look like this: ```rust ( meta_format_version: "1.0", processed_info: Some(( hash: 905599590923828066, full_hash: 9948823010183819117, process_dependencies: [], )), asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: Format(Basis), ), ), ) ``` To try basis-universal processing out in Bevy examples, (for example `sprite.rs`), change `add_plugins(DefaultPlugins)` to `add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev()))` and run with the `basis-universal` feature enabled: `cargo run --features=basis-universal --example sprite`. To create a custom processor, there are two main paths: 1. Use the `LoadAndSave` processor with an existing `AssetLoader`. Implement the `AssetSaver` trait, register the processor using `asset_processor.register_processor::<LoadAndSave<ImageLoader, CompressedImageSaver>>(image_saver.into())`. 2. Implement the `Process` trait directly and register it using: `asset_processor.register_processor(thing_processor)`. You can configure default processors for file extensions like this: ```rust asset_processor.set_default_processor::<ThingProcessor>("thing") ``` There is one more metadata type to be aware of: ```rust ( meta_format_version: "1.0", asset: Ignore, ) ``` This will ignore the asset during processing / prevent it from being written to `.imported_assets`. The AssetProcessor stores a transaction log at `.imported_assets/log` and uses it to gracefully recover from unexpected stops. This means you can force-quit the processor (and Bevy Apps running the processor in parallel) at arbitrary times! `.imported_assets` is "local state". It should _not_ be checked into source control. It should also be considered "read only". In practice, you _can_ modify processed assets and processed metadata if you really need to test something. But those modifications will not be represented in the hashes of the assets, so the processed state will be "out of sync" with the source assets. The processor _will not_ fix this for you. Either revert the change after you have tested it, or delete the processed files so they can be re-populated. ## Open Questions There are a number of open questions to be discussed. We should decide if they need to be addressed in this PR and if so, how we will address them: ### Implied Dependencies vs Dependency Enumeration There are currently two ways to populate asset dependencies: * **Implied via AssetLoaders**: if an AssetLoader loads an asset (and retrieves a handle), a dependency is added to the list. * **Explicit via the optional Asset::visit_dependencies**: if `server.load_asset(my_asset)` is called, it will call `my_asset.visit_dependencies`, which will grab dependencies that have been manually defined for the asset via the Asset trait impl (which can be derived). This means that defining explicit dependencies is optional for "loaded assets". And the list of dependencies is always accurate because loaders can only produce Handles if they register dependencies. If an asset was loaded with an AssetLoader, it only uses the implied dependencies. If an asset was created at runtime and added with `asset_server.load_asset(MyAsset)`, it will use `Asset::visit_dependencies`. However this can create a behavior mismatch between loaded assets and equivalent "created at runtime" assets if `Assets::visit_dependencies` doesn't exactly match the dependencies produced by the AssetLoader. This behavior mismatch can be resolved by completely removing "implied loader dependencies" and requiring `Asset::visit_dependencies` to supply dependency data. But this creates two problems: * It makes defining loaded assets harder and more error prone: Devs must remember to manually annotate asset dependencies with `#[dependency]` when deriving `Asset`. For more complicated assets (such as scenes), the derive likely wouldn't be sufficient and a manual `visit_dependencies` impl would be required. * Removes the ability to immediately kick off dependency loads: When AssetLoaders retrieve a Handle, they also immediately kick off an asset load for the handle, which means it can start loading in parallel _before_ the asset finishes loading. For large assets, this could be significant. (although this could be mitigated for processed assets if we store dependencies in the processed meta file and load them ahead of time) ### Eager ProcessorDev Asset Loading I made a controversial call in the interest of fast startup times ("time to first pixel") for the "processor dev mode configuration". When initializing the AssetProcessor, current processed versions of unchanged assets are yielded immediately, even if their dependencies haven't been checked yet for reprocessing. This means that non-current-state-of-filesystem-but-previously-valid assets might be returned to the App first, then hot-reloaded if/when their dependencies change and the asset is reprocessed. Is this behavior desirable? There is largely one alternative: do not yield an asset from the processor to the app until all of its dependencies have been checked for changes. In some common cases (load dependency has not changed since last run) this will increase startup time. The main question is "by how much" and is that slower startup time worth it in the interest of only yielding assets that are true to the current state of the filesystem. Should this be configurable? I'm starting to think we should only yield an asset after its (historical) dependencies have been checked for changes + processed as necessary, but I'm curious what you all think. ### Paths Are Currently The Only Canonical ID / Do We Want Asset UUIDs? In this implementation AssetPaths are the only canonical asset identifier (just like the previous Bevy Asset system and Godot). Moving assets will result in re-scans (and currently reprocessing, although reprocessing can easily be avoided with some changes). Asset renames/moves will break code and assets that rely on specific paths, unless those paths are fixed up. Do we want / need "stable asset uuids"? Introducing them is very possible: 1. Generate a UUID and include it in .meta files 2. Support UUID in AssetPath 3. Generate "asset indices" which are loaded on startup and map UUIDs to paths. 4 (maybe). Consider only supporting UUIDs for processed assets so we can generate quick-to-load indices instead of scanning meta files. The main "pro" is that assets referencing UUIDs don't need to be migrated when a path changes. The main "con" is that UUIDs cannot be "lazily resolved" like paths. They need a full view of all assets to answer the question "does this UUID exist". Which means UUIDs require the AssetProcessor to fully finish startup scans before saying an asset doesnt exist. And they essentially require asset pre-processing to use in apps, because scanning all asset metadata files at runtime to resolve a UUID is not viable for medium-to-large apps. It really requires a pre-generated UUID index, which must be loaded before querying for assets. I personally think this should be investigated in a separate PR. Paths aren't going anywhere ... _everyone_ uses filesystems (and filesystem-like apis) to manage their asset source files. I consider them permanent canonical asset information. Additionally, they behave well for both processed and unprocessed asset modes. Given that Bevy is supporting both, this feels like the right canonical ID to start with. UUIDS (and maybe even other indexed-identifier types) can be added later as necessary. ### Folder / File Naming Conventions All asset processing config currently lives in the `.imported_assets` folder. The processor transaction log is in `.imported_assets/log`. Processed assets are added to `.imported_assets/Default`, which will make migrating to processed asset profiles (ex: a `.imported_assets/Mobile` profile) a non-breaking change. It also allows us to create top-level files like `.imported_assets/log` without it being interpreted as an asset. Meta files currently have a `.meta` suffix. Do we like these names and conventions? ### Should the `AssetPlugin::processed_dev` configuration enable `watch_for_changes` automatically? Currently it does (which I think makes sense), but it does make it the only configuration that enables watch_for_changes by default. ### Discuss on_loaded High Level Interface: This PR includes a very rough "proof of concept" `on_loaded` system adapter that uses the `LoadedWithDependencies` event in combination with `asset_server.load_asset` dependency tracking to support this pattern ```rust fn main() { App::new() .init_asset::<MyAssets>() .add_systems(Update, on_loaded(create_array_texture)) .run(); } #[derive(Asset, Clone)] struct MyAssets { #[dependency] picture_of_my_cat: Handle<Image>, #[dependency] picture_of_my_other_cat: Handle<Image>, } impl FromWorld for ArrayTexture { fn from_world(world: &mut World) -> Self { picture_of_my_cat: server.load("meow.png"), picture_of_my_other_cat: server.load("meeeeeeeow.png"), } } fn spawn_cat(In(my_assets): In<MyAssets>, mut commands: Commands) { commands.spawn(SpriteBundle { texture: my_assets.picture_of_my_cat.clone(), ..default() }); commands.spawn(SpriteBundle { texture: my_assets.picture_of_my_other_cat.clone(), ..default() }); } ``` The implementation is _very_ rough. And it is currently unsafe because `bevy_ecs` doesn't expose some internals to do this safely from inside `bevy_asset`. There are plenty of unanswered questions like: * "do we add a Loadable" derive? (effectively automate the FromWorld implementation above) * Should `MyAssets` even be an Asset? (largely implemented this way because it elegantly builds on `server.load_asset(MyAsset { .. })` dependency tracking). We should think hard about what our ideal API looks like (and if this is a pattern we want to support). Not necessarily something we need to solve in this PR. The current `on_loaded` impl should probably be removed from this PR before merging. ## Clarifying Questions ### What about Assets as Entities? This Bevy Asset V2 proposal implementation initially stored Assets as ECS Entities. Instead of `AssetId<T>` + the `Assets<T>` resource it used `Entity` as the asset id and Asset values were just ECS components. There are plenty of compelling reasons to do this: 1. Easier to inline assets in Bevy Scenes (as they are "just" normal entities + components) 2. More flexible queries: use the power of the ECS to filter assets (ex: `Query<Mesh, With<Tree>>`). 3. Extensible. Users can add arbitrary component data to assets. 4. Things like "component visualization tools" work out of the box to visualize asset data. However Assets as Entities has a ton of caveats right now: * We need to be able to allocate entity ids without a direct World reference (aka rework id allocator in Entities ... i worked around this in my prototypes by just pre allocating big chunks of entities) * We want asset change events in addition to ECS change tracking ... how do we populate them when mutations can come from anywhere? Do we use Changed queries? This would require iterating over the change data for all assets every frame. Is this acceptable or should we implement a new "event based" component change detection option? * Reconciling manually created assets with asset-system managed assets has some nuance (ex: are they "loaded" / do they also have that component metadata?) * "how do we handle "static" / default entity handles" (ties in to the Entity Indices discussion: https://github.com/bevyengine/bevy/discussions/8319). This is necessary for things like "built in" assets and default handles in things like SpriteBundle. * Storing asset information as a component makes it easy to "invalidate" asset state by removing the component (or forcing modifications). Ideally we have ways to lock this down (some combination of Rust type privacy and ECS validation) In practice, how we store and identify assets is a reasonably superficial change (porting off of Assets as Entities and implementing dedicated storage + ids took less than a day). So once we sort out the remaining challenges the flip should be straightforward. Additionally, I do still have "Assets as Entities" in my commit history, so we can reuse that work. I personally think "assets as entities" is a good endgame, but it also doesn't provide _significant_ value at the moment and it certainly isn't ready yet with the current state of things. ### Why not Distill? [Distill](https://github.com/amethyst/distill) is a high quality fully featured asset system built in Rust. It is very natural to ask "why not just use Distill?". It is also worth calling out that for awhile, [we planned on adopting Distill / I signed off on it](https://github.com/bevyengine/bevy/issues/708). However I think Bevy has a number of constraints that make Distill adoption suboptimal: * **Architectural Simplicity:** * Distill's processor requires an in-memory database (lmdb) and RPC networked API (using Cap'n Proto). Each of these introduces API complexity that increases maintenance burden and "code grokability". Ignoring tests, documentation, and examples, Distill has 24,237 lines of Rust code (including generated code for RPC + database interactions). If you ignore generated code, it has 11,499 lines. * Bevy builds the AssetProcessor and AssetServer using pluggable AssetReader/AssetWriter Rust traits with simple io interfaces. They do not necessitate databases or RPC interfaces (although Readers/Writers could use them if that is desired). Bevy Asset V2 (at the time of writing this PR) is 5,384 lines of Rust code (ignoring tests, documentation, and examples). Grain of salt: Distill does have more features currently (ex: Asset Packing, GUIDS, remote-out-of-process asset processor). I do plan to implement these features in Bevy Asset V2 and I personally highly doubt they will meaningfully close the 6115 lines-of-code gap. * This complexity gap (which while illustrated by lines of code, is much bigger than just that) is noteworthy to me. Bevy should be hackable and there are pillars of Distill that are very hard to understand and extend. This is a matter of opinion (and Bevy Asset V2 also has complicated areas), but I think Bevy Asset V2 is much more approachable for the average developer. * Necessary disclaimer: counting lines of code is an extremely rough complexity metric. Read the code and form your own opinions. * **Optional Asset Processing:** Not all Bevy Apps (or Bevy App developers) need / want asset preprocessing. Processing increases the complexity of the development environment by introducing things like meta files, imported asset storage, running processors in the background, waiting for processing to finish, etc. Distill _requires_ preprocessing to work. With Bevy Asset V2 processing is fully opt-in. The AssetServer isn't directly aware of asset processors at all. AssetLoaders only care about converting bytes to runtime Assets ... they don't know or care if the bytes were pre-processed or not. Processing is "elegantly" (forgive my self-congratulatory phrasing) layered on top and builds on the existing Asset system primitives. * **Direct Filesystem Access to Processed Asset State:** Distill stores processed assets in a database. This makes debugging / inspecting the processed outputs harder (either requires special tooling to query the database or they need to be "deployed" to be inspected). Bevy Asset V2, on the other hand, stores processed assets in the filesystem (by default ... this is configurable). This makes interacting with the processed state more natural. Note that both Godot and Unity's new asset system store processed assets in the filesystem. * **Portability**: Because Distill's processor uses lmdb and RPC networking, it cannot be run on certain platforms (ex: lmdb is a non-rust dependency that cannot run on the web, some platforms don't support running network servers). Bevy should be able to process assets everywhere (ex: run the Bevy Editor on the web, compile + process shaders on mobile, etc). Distill does partially mitigate this problem by supporting "streaming" assets via the RPC protocol, but this is not a full solve from my perspective. And Bevy Asset V2 can (in theory) also stream assets (without requiring RPC, although this isn't implemented yet) Note that I _do_ still think Distill would be a solid asset system for Bevy. But I think the approach in this PR is a better solve for Bevy's specific "asset system requirements". ### Doesn't async-fs just shim requests to "sync" `std::fs`? What is the point? "True async file io" has limited / spotty platform support. async-fs (and the rust async ecosystem generally ... ex Tokio) currently use async wrappers over std::fs that offload blocking requests to separate threads. This may feel unsatisfying, but it _does_ still provide value because it prevents our task pools from blocking on file system operations (which would prevent progress when there are many tasks to do, but all threads in a pool are currently blocking on file system ops). Additionally, using async APIs for our AssetReaders and AssetWriters also provides value because we can later add support for "true async file io" for platforms that support it. _And_ we can implement other "true async io" asset backends (such as networked asset io). ## Draft TODO - [x] Fill in missing filesystem event APIs: file removed event (which is expressed as dangling RenameFrom events in some cases), file/folder renamed event - [x] Assets without loaders are not moved to the processed folder. This breaks things like referenced `.bin` files for GLTFs. This should be configurable per-non-asset-type. - [x] Initial implementation of Reflect and FromReflect for Handle. The "deserialization" parity bar is low here as this only worked with static UUIDs in the old impl ... this is a non-trivial problem. Either we add a Handle::AssetPath variant that gets "upgraded" to a strong handle on scene load or we use a separate AssetRef type for Bevy scenes (which is converted to a runtime Handle on load). This deserves its own discussion in a different pr. - [x] Populate read_asset_bytes hash when run by the processor (a bit of a special case .. when run by the processor the processed meta will contain the hash so we don't need to compute it on the spot, but we don't want/need to read the meta when run by the main AssetServer) - [x] Delay hot reloading: currently filesystem events are handled immediately, which creates timing issues in some cases. For example hot reloading images can sometimes break because the image isn't finished writing. We should add a delay, likely similar to the [implementation in this PR](https://github.com/bevyengine/bevy/pull/8503). - [x] Port old platform-specific AssetIo implementations to the new AssetReader interface (currently missing Android and web) - [x] Resolve on_loaded unsafety (either by removing the API entirely or removing the unsafe) - [x] Runtime loader setting overrides - [x] Remove remaining unwraps that should be error-handled. There are number of TODOs here - [x] Pretty AssetPath Display impl - [x] Document more APIs - [x] Resolve spurious "reloading because it has changed" events (to repro run load_gltf with `processed_dev()`) - [x] load_dependency hot reloading currently only works for processed assets. If processing is disabled, load_dependency changes are not hot reloaded. - [x] Replace AssetInfo dependency load/fail counters with `loading_dependencies: HashSet<UntypedAssetId>` to prevent reloads from (potentially) breaking counters. Storing this will also enable "dependency reloaded" events (see [Next Steps](#next-steps)) - [x] Re-add filesystem watcher cargo feature gate (currently it is not optional) - [ ] Migration Guide - [ ] Changelog ## Followup TODO - [ ] Replace "eager unchanged processed asset loading" behavior with "don't returned unchanged processed asset until dependencies have been checked". - [ ] Add true `Ignore` AssetAction that does not copy the asset to the imported_assets folder. - [ ] Finish "live asset unloading" (ex: free up CPU asset memory after uploading an image to the GPU), rethink RenderAssets, and port renderer features. The `Assets` collection uses `Option<T>` for asset storage to support its removal. (1) the Option might not actually be necessary ... might be able to just remove from the collection entirely (2) need to finalize removal apis - [ ] Try replacing the "channel based" asset id recycling with something a bit more efficient (ex: we might be able to use raw atomic ints with some cleverness) - [ ] Consider adding UUIDs to processed assets (scoped just to helping identify moved assets ... not exposed to load queries ... see [Next Steps](#next-steps)) - [ ] Store "last modified" source asset and meta timestamps in processed meta files to enable skipping expensive hashing when the file wasn't changed - [ ] Fix "slow loop" handle drop fix - [ ] Migrate to TypeName - [x] Handle "loader preregistration". See #9429 ## Next Steps * **Configurable per-type defaults for AssetMeta**: It should be possible to add configuration like "all png image meta should default to using nearest sampling" (currently this hard-coded per-loader/processor Settings::default() impls). Also see the "Folder Meta" bullet point. * **Avoid Reprocessing on Asset Renames / Moves**: See the "canonical asset ids" discussion in [Open Questions](#open-questions) and the relevant bullet point in [Draft TODO](#draft-todo). Even without canonical ids, folder renames could avoid reprocessing in some cases. * **Multiple Asset Sources**: Expand AssetPath to support "asset source names" and support multiple AssetReaders in the asset server (ex: `webserver://some_path/image.png` backed by an Http webserver AssetReader). The "default" asset reader would use normal `some_path/image.png` paths. Ideally this works in combination with multiple AssetWatchers for hot-reloading * **Stable Type Names**: this pr removes the TypeUuid requirement from assets in favor of `std::any::type_name`. This makes defining assets easier (no need to generate a new uuid / use weird proc macro syntax). It also makes reading meta files easier (because things have "friendly names"). We also use type names for components in scene files. If they are good enough for components, they are good enough for assets. And consistency across Bevy pillars is desirable. However, `std::any::type_name` is not guaranteed to be stable (although in practice it is). We've developed a [stable type path](https://github.com/bevyengine/bevy/pull/7184) to resolve this, which should be adopted when it is ready. * **Command Line Interface**: It should be possible to run the asset processor in a separate process from the command line. This will also require building a network-server-backed AssetReader to communicate between the app and the processor. We've been planning to build a "bevy cli" for awhile. This seems like a good excuse to build it. * **Asset Packing**: This is largely an additive feature, so it made sense to me to punt this until we've laid the foundations in this PR. * **Per-Platform Processed Assets**: It should be possible to generate assets for multiple platforms by supporting multiple "processor profiles" per asset (ex: compress with format X on PC and Y on iOS). I think there should probably be arbitrary "profiles" (which can be separate from actual platforms), which are then assigned to a given platform when generating the final asset distribution for that platform. Ex: maybe devs want a "Mobile" profile that is shared between iOS and Android. Or a "LowEnd" profile shared between web and mobile. * **Versioning and Migrations**: Assets, Loaders, Savers, and Processors need to have versions to determine if their schema is valid. If an asset / loader version is incompatible with the current version expected at runtime, the processor should be able to migrate them. I think we should try using Bevy Reflect for this, as it would allow us to load the old version as a dynamic Reflect type without actually having the old Rust type. It would also allow us to define "patches" to migrate between versions (Bevy Reflect devs are currently working on patching). The `.meta` file already has its own format version. Migrating that to new versions should also be possible. * **Real Copy-on-write AssetPaths**: Rust's actual Cow (clone-on-write type) currently used by AssetPath can still result in String clones that aren't actually necessary (cloning an Owned Cow clones the contents). Bevy's asset system requires cloning AssetPaths in a number of places, which result in actual clones of the internal Strings. This is not efficient. AssetPath internals should be reworked to exhibit truer cow-like-behavior that reduces String clones to the absolute minimum. * **Consider processor-less processing**: In theory the AssetServer could run processors "inline" even if the background AssetProcessor is disabled. If we decide this is actually desirable, we could add this. But I don't think its a priority in the short or medium term. * **Pre-emptive dependency loading**: We could encode dependencies in processed meta files, which could then be used by the Asset Server to kick of dependency loads as early as possible (prior to starting the actual asset load). Is this desirable? How much time would this save in practice? * **Optimize Processor With UntypedAssetIds**: The processor exclusively uses AssetPath to identify assets currently. It might be possible to swap these out for UntypedAssetIds in some places, which are smaller / cheaper to hash and compare. * **One to Many Asset Processing**: An asset source file that produces many assets currently must be processed into a single "processed" asset source. If labeled assets can be written separately they can each have their own configured savers _and_ they could be loaded more granularly. Definitely worth exploring! * **Automatically Track "Runtime-only" Asset Dependencies**: Right now, tracking "created at runtime" asset dependencies requires adding them via `asset_server.load_asset(StandardMaterial::default())`. I think with some cleverness we could also do this for `materials.add(StandardMaterial::default())`, making tracking work "everywhere". There are challenges here relating to change detection / ensuring the server is made aware of dependency changes. This could be expensive in some cases. * **"Dependency Changed" events**: Some assets have runtime artifacts that need to be re-generated when one of their dependencies change (ex: regenerate a material's bind group when a Texture needs to change). We are generating the dependency graph so we can definitely produce these events. Buuuuut generating these events will have a cost / they could be high frequency for some assets, so we might want this to be opt-in for specific cases. * **Investigate Storing More Information In Handles**: Handles can now store arbitrary information, which makes it cheaper and easier to access. How much should we move into them? Canonical asset load states (via atomics)? (`handle.is_loaded()` would be very cool). Should we store the entire asset and remove the `Assets<T>` collection? (`Arc<RwLock<Option<Image>>>`?) * **Support processing and loading files without extensions**: This is a pretty arbitrary restriction and could be supported with very minimal changes. * **Folder Meta**: It would be nice if we could define per folder processor configuration defaults (likely in a `.meta` or `.folder_meta` file). Things like "default to linear filtering for all Images in this folder". * **Replace async_broadcast with event-listener?** This might be approximately drop-in for some uses and it feels more light weight * **Support Running the AssetProcessor on the Web**: Most of the hard work is done here, but there are some easy straggling TODOs (make the transaction log an interface instead of a direct file writer so we can write a web storage backend, implement an AssetReader/AssetWriter that reads/writes to something like LocalStorage). * **Consider identifying and preventing circular dependencies**: This is especially important for "processor dependencies", as processing will silently never finish in these cases. * **Built-in/Inlined Asset Hot Reloading**: This PR regresses "built-in/inlined" asset hot reloading (previously provided by the DebugAssetServer). I'm intentionally punting this because I think it can be cleanly implemented with "multiple asset sources" by registering a "debug asset source" (ex: `debug://bevy_pbr/src/render/pbr.wgsl` asset paths) in combination with an AssetWatcher for that asset source and support for "manually loading pats with asset bytes instead of AssetReaders". The old DebugAssetServer was quite nasty and I'd love to avoid that hackery going forward. * **Investigate ways to remove double-parsing meta files**: Parsing meta files currently involves parsing once with "minimal" versions of the meta file to extract the type name of the loader/processor config, then parsing again to parse the "full" meta. This is suboptimal. We should be able to define custom deserializers that (1) assume the loader/processor type name comes first (2) dynamically looks up the loader/processor registrations to deserialize settings in-line (similar to components in the bevy scene format). Another alternative: deserialize as dynamic Reflect objects and then convert. * **More runtime loading configuration**: Support using the Handle type as a hint to select an asset loader (instead of relying on AssetPath extensions) * **More high level Processor trait implementations**: For example, it might be worth adding support for arbitrary chains of "asset transforms" that modify an in-memory asset representation between loading and saving. (ex: load a Mesh, run a `subdivide_mesh` transform, followed by a `flip_normals` transform, then save the mesh to an efficient compressed format). * **Bevy Scene Handle Deserialization**: (see the relevant [Draft TODO item](#draft-todo) for context) * **Explore High Level Load Interfaces**: See [this discussion](#discuss-on_loaded-high-level-interface) for one prototype. * **Asset Streaming**: It would be great if we could stream Assets (ex: stream a long video file piece by piece) * **ID Exchanging**: In this PR Asset Handles/AssetIds are bigger than they need to be because they have a Uuid enum variant. If we implement an "id exchanging" system that trades Uuids for "efficient runtime ids", we can cut down on the size of AssetIds, making them more efficient. This has some open design questions, such as how to spawn entities with "default" handle values (as these wouldn't have access to the exchange api in the current system). * **Asset Path Fixup Tooling**: Assets that inline asset paths inside them will break when an asset moves. The asset system provides the functionality to detect when paths break. We should build a framework that enables formats to define "path migrations". This is especially important for scene files. For editor-generated files, we should also consider using UUIDs (see other bullet point) to avoid the need to migrate in these cases. --------- Co-authored-by: BeastLe9enD <beastle9end@outlook.de> Co-authored-by: Mike <mike.hsu@gmail.com> Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com>
2023-09-07 02:07:27 +00:00
[package.metadata.example.custom_asset_reader]
name = "Custom Asset IO"
Bevy Asset V2 (#8624) # Bevy Asset V2 Proposal ## Why Does Bevy Need A New Asset System? Asset pipelines are a central part of the gamedev process. Bevy's current asset system is missing a number of features that make it non-viable for many classes of gamedev. After plenty of discussions and [a long community feedback period](https://github.com/bevyengine/bevy/discussions/3972), we've identified a number missing features: * **Asset Preprocessing**: it should be possible to "preprocess" / "compile" / "crunch" assets at "development time" rather than when the game starts up. This enables offloading expensive work from deployed apps, faster asset loading, less runtime memory usage, etc. * **Per-Asset Loader Settings**: Individual assets cannot define their own loaders that override the defaults. Additionally, they cannot provide per-asset settings to their loaders. This is a huge limitation, as many asset types don't provide all information necessary for Bevy _inside_ the asset. For example, a raw PNG image says nothing about how it should be sampled (ex: linear vs nearest). * **Asset `.meta` files**: assets should have configuration files stored adjacent to the asset in question, which allows the user to configure asset-type-specific settings. These settings should be accessible during the pre-processing phase. Modifying a `.meta` file should trigger a re-processing / re-load of the asset. It should be possible to configure asset loaders from the meta file. * **Processed Asset Hot Reloading**: Changes to processed assets (or their dependencies) should result in re-processing them and re-loading the results in live Bevy Apps. * **Asset Dependency Tracking**: The current bevy_asset has no good way to wait for asset dependencies to load. It punts this as an exercise for consumers of the loader apis, which is unreasonable and error prone. There should be easy, ergonomic ways to wait for assets to load and block some logic on an asset's entire dependency tree loading. * **Runtime Asset Loading**: it should be (optionally) possible to load arbitrary assets dynamically at runtime. This necessitates being able to deploy and run the asset server alongside Bevy Apps on _all platforms_. For example, we should be able to invoke the shader compiler at runtime, stream scenes from sources like the internet, etc. To keep deployed binaries (and startup times) small, the runtime asset server configuration should be configurable with different settings compared to the "pre processor asset server". * **Multiple Backends**: It should be possible to load assets from arbitrary sources (filesystems, the internet, remote asset serves, etc). * **Asset Packing**: It should be possible to deploy assets in compressed "packs", which makes it easier and more efficient to distribute assets with Bevy Apps. * **Asset Handoff**: It should be possible to hold a "live" asset handle, which correlates to runtime data, without actually holding the asset in memory. Ex: it must be possible to hold a reference to a GPU mesh generated from a "mesh asset" without keeping the mesh data in CPU memory * **Per-Platform Processed Assets**: Different platforms and app distributions have different capabilities and requirements. Some platforms need lower asset resolutions or different asset formats to operate within the hardware constraints of the platform. It should be possible to define per-platform asset processing profiles. And it should be possible to deploy only the assets required for a given platform. These features have architectural implications that are significant enough to require a full rewrite. The current Bevy Asset implementation got us this far, but it can take us no farther. This PR defines a brand new asset system that implements most of these features, while laying the foundations for the remaining features to be built. ## Bevy Asset V2 Here is a quick overview of the features introduced in this PR. * **Asset Preprocessing**: Preprocess assets at development time into more efficient (and configurable) representations * **Dependency Aware**: Dependencies required to process an asset are tracked. If an asset's processed dependency changes, it will be reprocessed * **Hot Reprocessing/Reloading**: detect changes to asset source files, reprocess them if they have changed, and then hot-reload them in Bevy Apps. * **Only Process Changes**: Assets are only re-processed when their source file (or meta file) has changed. This uses hashing and timestamps to avoid processing assets that haven't changed. * **Transactional and Reliable**: Uses write-ahead logging (a technique commonly used by databases) to recover from crashes / forced-exits. Whenever possible it avoids full-reprocessing / only uncompleted transactions will be reprocessed. When the processor is running in parallel with a Bevy App, processor asset writes block Bevy App asset reads. Reading metadata + asset bytes is guaranteed to be transactional / correctly paired. * **Portable / Run anywhere / Database-free**: The processor does not rely on an in-memory database (although it uses some database techniques for reliability). This is important because pretty much all in-memory databases have unsupported platforms or build complications. * **Configure Processor Defaults Per File Type**: You can say "use this processor for all files of this type". * **Custom Processors**: The `Processor` trait is flexible and unopinionated. It can be implemented by downstream plugins. * **LoadAndSave Processors**: Most asset processing scenarios can be expressed as "run AssetLoader A, save the results using AssetSaver X, and then load the result using AssetLoader B". For example, load this png image using `PngImageLoader`, which produces an `Image` asset and then save it using `CompressedImageSaver` (which also produces an `Image` asset, but in a compressed format), which takes an `Image` asset as input. This means if you have an `AssetLoader` for an asset, you are already half way there! It also means that you can share AssetSavers across multiple loaders. Because `CompressedImageSaver` accepts Bevy's generic Image asset as input, it means you can also use it with some future `JpegImageLoader`. * **Loader and Saver Settings**: Asset Loaders and Savers can now define their own settings types, which are passed in as input when an asset is loaded / saved. Each asset can define its own settings. * **Asset `.meta` files**: configure asset loaders, their settings, enable/disable processing, and configure processor settings * **Runtime Asset Dependency Tracking** Runtime asset dependencies (ex: if an asset contains a `Handle<Image>`) are tracked by the asset server. An event is emitted when an asset and all of its dependencies have been loaded * **Unprocessed Asset Loading**: Assets do not require preprocessing. They can be loaded directly. A processed asset is just a "normal" asset with some extra metadata. Asset Loaders don't need to know or care about whether or not an asset was processed. * **Async Asset IO**: Asset readers/writers use async non-blocking interfaces. Note that because Rust doesn't yet support async traits, there is a bit of manual Boxing / Future boilerplate. This will hopefully be removed in the near future when Rust gets async traits. * **Pluggable Asset Readers and Writers**: Arbitrary asset source readers/writers are supported, both by the processor and the asset server. * **Better Asset Handles** * **Single Arc Tree**: Asset Handles now use a single arc tree that represents the lifetime of the asset. This makes their implementation simpler, more efficient, and allows us to cheaply attach metadata to handles. Ex: the AssetPath of a handle is now directly accessible on the handle itself! * **Const Typed Handles**: typed handles can be constructed in a const context. No more weird "const untyped converted to typed at runtime" patterns! * **Handles and Ids are Smaller / Faster To Hash / Compare**: Typed `Handle<T>` is now much smaller in memory and `AssetId<T>` is even smaller. * **Weak Handle Usage Reduction**: In general Handles are now considered to be "strong". Bevy features that previously used "weak `Handle<T>`" have been ported to `AssetId<T>`, which makes it statically clear that the features do not hold strong handles (while retaining strong type information). Currently Handle::Weak still exists, but it is very possible that we can remove that entirely. * **Efficient / Dense Asset Ids**: Assets now have efficient dense runtime asset ids, which means we can avoid expensive hash lookups. Assets are stored in Vecs instead of HashMaps. There are now typed and untyped ids, which means we no longer need to store dynamic type information in the ID for typed handles. "AssetPathId" (which was a nightmare from a performance and correctness standpoint) has been entirely removed in favor of dense ids (which are retrieved for a path on load) * **Direct Asset Loading, with Dependency Tracking**: Assets that are defined at runtime can still have their dependencies tracked by the Asset Server (ex: if you create a material at runtime, you can still wait for its textures to load). This is accomplished via the (currently optional) "asset dependency visitor" trait. This system can also be used to define a set of assets to load, then wait for those assets to load. * **Async folder loading**: Folder loading also uses this system and immediately returns a handle to the LoadedFolder asset, which means folder loading no longer blocks on directory traversals. * **Improved Loader Interface**: Loaders now have a specific "top level asset type", which makes returning the top-level asset simpler and statically typed. * **Basic Image Settings and Processing**: Image assets can now be processed into the gpu-friendly Basic Universal format. The ImageLoader now has a setting to define what format the image should be loaded as. Note that this is just a minimal MVP ... plenty of additional work to do here. To demo this, enable the `basis-universal` feature and turn on asset processing. * **Simpler Audio Play / AudioSink API**: Asset handle providers are cloneable, which means the Audio resource can mint its own handles. This means you can now do `let sink_handle = audio.play(music)` instead of `let sink_handle = audio_sinks.get_handle(audio.play(music))`. Note that this might still be replaced by https://github.com/bevyengine/bevy/pull/8424. **Removed Handle Casting From Engine Features**: Ex: FontAtlases no longer use casting between handle types ## Using The New Asset System ### Normal Unprocessed Asset Loading By default the `AssetPlugin` does not use processing. It behaves pretty much the same way as the old system. If you are defining a custom asset, first derive `Asset`: ```rust #[derive(Asset)] struct Thing { value: String, } ``` Initialize the asset: ```rust app.init_asset:<Thing>() ``` Implement a new `AssetLoader` for it: ```rust #[derive(Default)] struct ThingLoader; #[derive(Serialize, Deserialize, Default)] pub struct ThingSettings { some_setting: bool, } impl AssetLoader for ThingLoader { type Asset = Thing; type Settings = ThingSettings; fn load<'a>( &'a self, reader: &'a mut Reader, settings: &'a ThingSettings, load_context: &'a mut LoadContext, ) -> BoxedFuture<'a, Result<Thing, anyhow::Error>> { Box::pin(async move { let mut bytes = Vec::new(); reader.read_to_end(&mut bytes).await?; // convert bytes to value somehow Ok(Thing { value }) }) } fn extensions(&self) -> &[&str] { &["thing"] } } ``` Note that this interface will get much cleaner once Rust gets support for async traits. `Reader` is an async futures_io::AsyncRead. You can stream bytes as they come in or read them all into a `Vec<u8>`, depending on the context. You can use `let handle = load_context.load(path)` to kick off a dependency load, retrieve a handle, and register the dependency for the asset. Then just register the loader in your Bevy app: ```rust app.init_asset_loader::<ThingLoader>() ``` Now just add your `Thing` asset files into the `assets` folder and load them like this: ```rust fn system(asset_server: Res<AssetServer>) { let handle = Handle<Thing> = asset_server.load("cool.thing"); } ``` You can check load states directly via the asset server: ```rust if asset_server.load_state(&handle) == LoadState::Loaded { } ``` You can also listen for events: ```rust fn system(mut events: EventReader<AssetEvent<Thing>>, handle: Res<SomeThingHandle>) { for event in events.iter() { if event.is_loaded_with_dependencies(&handle) { } } } ``` Note the new `AssetEvent::LoadedWithDependencies`, which only fires when the asset is loaded _and_ all dependencies (and their dependencies) have loaded. Unlike the old asset system, for a given asset path all `Handle<T>` values point to the same underlying Arc. This means Handles can cheaply hold more asset information, such as the AssetPath: ```rust // prints the AssetPath of the handle info!("{:?}", handle.path()) ``` ### Processed Assets Asset processing can be enabled via the `AssetPlugin`. When developing Bevy Apps with processed assets, do this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev())) ``` This runs the `AssetProcessor` in the background with hot-reloading. It reads assets from the `assets` folder, processes them, and writes them to the `.imported_assets` folder. Asset loads in the Bevy App will wait for a processed version of the asset to become available. If an asset in the `assets` folder changes, it will be reprocessed and hot-reloaded in the Bevy App. When deploying processed Bevy apps, do this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::processed())) ``` This does not run the `AssetProcessor` in the background. It behaves like `AssetPlugin::unprocessed()`, but reads assets from `.imported_assets`. When the `AssetProcessor` is running, it will populate sibling `.meta` files for assets in the `assets` folder. Meta files for assets that do not have a processor configured look like this: ```rust ( meta_format_version: "1.0", asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: FromExtension, ), ), ) ``` This is metadata for an image asset. For example, if you have `assets/my_sprite.png`, this could be the metadata stored at `assets/my_sprite.png.meta`. Meta files are totally optional. If no metadata exists, the default settings will be used. In short, this file says "load this asset with the ImageLoader and use the file extension to determine the image type". This type of meta file is supported in all AssetPlugin modes. If in `Unprocessed` mode, the asset (with the meta settings) will be loaded directly. If in `ProcessedDev` mode, the asset file will be copied directly to the `.imported_assets` folder. The meta will also be copied directly to the `.imported_assets` folder, but with one addition: ```rust ( meta_format_version: "1.0", processed_info: Some(( hash: 12415480888597742505, full_hash: 14344495437905856884, process_dependencies: [], )), asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: FromExtension, ), ), ) ``` `processed_info` contains `hash` (a direct hash of the asset and meta bytes), `full_hash` (a hash of `hash` and the hashes of all `process_dependencies`), and `process_dependencies` (the `path` and `full_hash` of every process_dependency). A "process dependency" is an asset dependency that is _directly_ used when processing the asset. Images do not have process dependencies, so this is empty. When the processor is enabled, you can use the `Process` metadata config: ```rust ( meta_format_version: "1.0", asset: Process( processor: "bevy_asset::processor::process::LoadAndSave<bevy_render::texture::image_loader::ImageLoader, bevy_render::texture::compressed_image_saver::CompressedImageSaver>", settings: ( loader_settings: ( format: FromExtension, ), saver_settings: ( generate_mipmaps: true, ), ), ), ) ``` This configures the asset to use the `LoadAndSave` processor, which runs an AssetLoader and feeds the result into an AssetSaver (which saves the given Asset and defines a loader to load it with). (for terseness LoadAndSave will likely get a shorter/friendlier type name when [Stable Type Paths](#7184) lands). `LoadAndSave` is likely to be the most common processor type, but arbitrary processors are supported. `CompressedImageSaver` saves an `Image` in the Basis Universal format and configures the ImageLoader to load it as basis universal. The `AssetProcessor` will read this meta, run it through the LoadAndSave processor, and write the basis-universal version of the image to `.imported_assets`. The final metadata will look like this: ```rust ( meta_format_version: "1.0", processed_info: Some(( hash: 905599590923828066, full_hash: 9948823010183819117, process_dependencies: [], )), asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: Format(Basis), ), ), ) ``` To try basis-universal processing out in Bevy examples, (for example `sprite.rs`), change `add_plugins(DefaultPlugins)` to `add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev()))` and run with the `basis-universal` feature enabled: `cargo run --features=basis-universal --example sprite`. To create a custom processor, there are two main paths: 1. Use the `LoadAndSave` processor with an existing `AssetLoader`. Implement the `AssetSaver` trait, register the processor using `asset_processor.register_processor::<LoadAndSave<ImageLoader, CompressedImageSaver>>(image_saver.into())`. 2. Implement the `Process` trait directly and register it using: `asset_processor.register_processor(thing_processor)`. You can configure default processors for file extensions like this: ```rust asset_processor.set_default_processor::<ThingProcessor>("thing") ``` There is one more metadata type to be aware of: ```rust ( meta_format_version: "1.0", asset: Ignore, ) ``` This will ignore the asset during processing / prevent it from being written to `.imported_assets`. The AssetProcessor stores a transaction log at `.imported_assets/log` and uses it to gracefully recover from unexpected stops. This means you can force-quit the processor (and Bevy Apps running the processor in parallel) at arbitrary times! `.imported_assets` is "local state". It should _not_ be checked into source control. It should also be considered "read only". In practice, you _can_ modify processed assets and processed metadata if you really need to test something. But those modifications will not be represented in the hashes of the assets, so the processed state will be "out of sync" with the source assets. The processor _will not_ fix this for you. Either revert the change after you have tested it, or delete the processed files so they can be re-populated. ## Open Questions There are a number of open questions to be discussed. We should decide if they need to be addressed in this PR and if so, how we will address them: ### Implied Dependencies vs Dependency Enumeration There are currently two ways to populate asset dependencies: * **Implied via AssetLoaders**: if an AssetLoader loads an asset (and retrieves a handle), a dependency is added to the list. * **Explicit via the optional Asset::visit_dependencies**: if `server.load_asset(my_asset)` is called, it will call `my_asset.visit_dependencies`, which will grab dependencies that have been manually defined for the asset via the Asset trait impl (which can be derived). This means that defining explicit dependencies is optional for "loaded assets". And the list of dependencies is always accurate because loaders can only produce Handles if they register dependencies. If an asset was loaded with an AssetLoader, it only uses the implied dependencies. If an asset was created at runtime and added with `asset_server.load_asset(MyAsset)`, it will use `Asset::visit_dependencies`. However this can create a behavior mismatch between loaded assets and equivalent "created at runtime" assets if `Assets::visit_dependencies` doesn't exactly match the dependencies produced by the AssetLoader. This behavior mismatch can be resolved by completely removing "implied loader dependencies" and requiring `Asset::visit_dependencies` to supply dependency data. But this creates two problems: * It makes defining loaded assets harder and more error prone: Devs must remember to manually annotate asset dependencies with `#[dependency]` when deriving `Asset`. For more complicated assets (such as scenes), the derive likely wouldn't be sufficient and a manual `visit_dependencies` impl would be required. * Removes the ability to immediately kick off dependency loads: When AssetLoaders retrieve a Handle, they also immediately kick off an asset load for the handle, which means it can start loading in parallel _before_ the asset finishes loading. For large assets, this could be significant. (although this could be mitigated for processed assets if we store dependencies in the processed meta file and load them ahead of time) ### Eager ProcessorDev Asset Loading I made a controversial call in the interest of fast startup times ("time to first pixel") for the "processor dev mode configuration". When initializing the AssetProcessor, current processed versions of unchanged assets are yielded immediately, even if their dependencies haven't been checked yet for reprocessing. This means that non-current-state-of-filesystem-but-previously-valid assets might be returned to the App first, then hot-reloaded if/when their dependencies change and the asset is reprocessed. Is this behavior desirable? There is largely one alternative: do not yield an asset from the processor to the app until all of its dependencies have been checked for changes. In some common cases (load dependency has not changed since last run) this will increase startup time. The main question is "by how much" and is that slower startup time worth it in the interest of only yielding assets that are true to the current state of the filesystem. Should this be configurable? I'm starting to think we should only yield an asset after its (historical) dependencies have been checked for changes + processed as necessary, but I'm curious what you all think. ### Paths Are Currently The Only Canonical ID / Do We Want Asset UUIDs? In this implementation AssetPaths are the only canonical asset identifier (just like the previous Bevy Asset system and Godot). Moving assets will result in re-scans (and currently reprocessing, although reprocessing can easily be avoided with some changes). Asset renames/moves will break code and assets that rely on specific paths, unless those paths are fixed up. Do we want / need "stable asset uuids"? Introducing them is very possible: 1. Generate a UUID and include it in .meta files 2. Support UUID in AssetPath 3. Generate "asset indices" which are loaded on startup and map UUIDs to paths. 4 (maybe). Consider only supporting UUIDs for processed assets so we can generate quick-to-load indices instead of scanning meta files. The main "pro" is that assets referencing UUIDs don't need to be migrated when a path changes. The main "con" is that UUIDs cannot be "lazily resolved" like paths. They need a full view of all assets to answer the question "does this UUID exist". Which means UUIDs require the AssetProcessor to fully finish startup scans before saying an asset doesnt exist. And they essentially require asset pre-processing to use in apps, because scanning all asset metadata files at runtime to resolve a UUID is not viable for medium-to-large apps. It really requires a pre-generated UUID index, which must be loaded before querying for assets. I personally think this should be investigated in a separate PR. Paths aren't going anywhere ... _everyone_ uses filesystems (and filesystem-like apis) to manage their asset source files. I consider them permanent canonical asset information. Additionally, they behave well for both processed and unprocessed asset modes. Given that Bevy is supporting both, this feels like the right canonical ID to start with. UUIDS (and maybe even other indexed-identifier types) can be added later as necessary. ### Folder / File Naming Conventions All asset processing config currently lives in the `.imported_assets` folder. The processor transaction log is in `.imported_assets/log`. Processed assets are added to `.imported_assets/Default`, which will make migrating to processed asset profiles (ex: a `.imported_assets/Mobile` profile) a non-breaking change. It also allows us to create top-level files like `.imported_assets/log` without it being interpreted as an asset. Meta files currently have a `.meta` suffix. Do we like these names and conventions? ### Should the `AssetPlugin::processed_dev` configuration enable `watch_for_changes` automatically? Currently it does (which I think makes sense), but it does make it the only configuration that enables watch_for_changes by default. ### Discuss on_loaded High Level Interface: This PR includes a very rough "proof of concept" `on_loaded` system adapter that uses the `LoadedWithDependencies` event in combination with `asset_server.load_asset` dependency tracking to support this pattern ```rust fn main() { App::new() .init_asset::<MyAssets>() .add_systems(Update, on_loaded(create_array_texture)) .run(); } #[derive(Asset, Clone)] struct MyAssets { #[dependency] picture_of_my_cat: Handle<Image>, #[dependency] picture_of_my_other_cat: Handle<Image>, } impl FromWorld for ArrayTexture { fn from_world(world: &mut World) -> Self { picture_of_my_cat: server.load("meow.png"), picture_of_my_other_cat: server.load("meeeeeeeow.png"), } } fn spawn_cat(In(my_assets): In<MyAssets>, mut commands: Commands) { commands.spawn(SpriteBundle { texture: my_assets.picture_of_my_cat.clone(), ..default() }); commands.spawn(SpriteBundle { texture: my_assets.picture_of_my_other_cat.clone(), ..default() }); } ``` The implementation is _very_ rough. And it is currently unsafe because `bevy_ecs` doesn't expose some internals to do this safely from inside `bevy_asset`. There are plenty of unanswered questions like: * "do we add a Loadable" derive? (effectively automate the FromWorld implementation above) * Should `MyAssets` even be an Asset? (largely implemented this way because it elegantly builds on `server.load_asset(MyAsset { .. })` dependency tracking). We should think hard about what our ideal API looks like (and if this is a pattern we want to support). Not necessarily something we need to solve in this PR. The current `on_loaded` impl should probably be removed from this PR before merging. ## Clarifying Questions ### What about Assets as Entities? This Bevy Asset V2 proposal implementation initially stored Assets as ECS Entities. Instead of `AssetId<T>` + the `Assets<T>` resource it used `Entity` as the asset id and Asset values were just ECS components. There are plenty of compelling reasons to do this: 1. Easier to inline assets in Bevy Scenes (as they are "just" normal entities + components) 2. More flexible queries: use the power of the ECS to filter assets (ex: `Query<Mesh, With<Tree>>`). 3. Extensible. Users can add arbitrary component data to assets. 4. Things like "component visualization tools" work out of the box to visualize asset data. However Assets as Entities has a ton of caveats right now: * We need to be able to allocate entity ids without a direct World reference (aka rework id allocator in Entities ... i worked around this in my prototypes by just pre allocating big chunks of entities) * We want asset change events in addition to ECS change tracking ... how do we populate them when mutations can come from anywhere? Do we use Changed queries? This would require iterating over the change data for all assets every frame. Is this acceptable or should we implement a new "event based" component change detection option? * Reconciling manually created assets with asset-system managed assets has some nuance (ex: are they "loaded" / do they also have that component metadata?) * "how do we handle "static" / default entity handles" (ties in to the Entity Indices discussion: https://github.com/bevyengine/bevy/discussions/8319). This is necessary for things like "built in" assets and default handles in things like SpriteBundle. * Storing asset information as a component makes it easy to "invalidate" asset state by removing the component (or forcing modifications). Ideally we have ways to lock this down (some combination of Rust type privacy and ECS validation) In practice, how we store and identify assets is a reasonably superficial change (porting off of Assets as Entities and implementing dedicated storage + ids took less than a day). So once we sort out the remaining challenges the flip should be straightforward. Additionally, I do still have "Assets as Entities" in my commit history, so we can reuse that work. I personally think "assets as entities" is a good endgame, but it also doesn't provide _significant_ value at the moment and it certainly isn't ready yet with the current state of things. ### Why not Distill? [Distill](https://github.com/amethyst/distill) is a high quality fully featured asset system built in Rust. It is very natural to ask "why not just use Distill?". It is also worth calling out that for awhile, [we planned on adopting Distill / I signed off on it](https://github.com/bevyengine/bevy/issues/708). However I think Bevy has a number of constraints that make Distill adoption suboptimal: * **Architectural Simplicity:** * Distill's processor requires an in-memory database (lmdb) and RPC networked API (using Cap'n Proto). Each of these introduces API complexity that increases maintenance burden and "code grokability". Ignoring tests, documentation, and examples, Distill has 24,237 lines of Rust code (including generated code for RPC + database interactions). If you ignore generated code, it has 11,499 lines. * Bevy builds the AssetProcessor and AssetServer using pluggable AssetReader/AssetWriter Rust traits with simple io interfaces. They do not necessitate databases or RPC interfaces (although Readers/Writers could use them if that is desired). Bevy Asset V2 (at the time of writing this PR) is 5,384 lines of Rust code (ignoring tests, documentation, and examples). Grain of salt: Distill does have more features currently (ex: Asset Packing, GUIDS, remote-out-of-process asset processor). I do plan to implement these features in Bevy Asset V2 and I personally highly doubt they will meaningfully close the 6115 lines-of-code gap. * This complexity gap (which while illustrated by lines of code, is much bigger than just that) is noteworthy to me. Bevy should be hackable and there are pillars of Distill that are very hard to understand and extend. This is a matter of opinion (and Bevy Asset V2 also has complicated areas), but I think Bevy Asset V2 is much more approachable for the average developer. * Necessary disclaimer: counting lines of code is an extremely rough complexity metric. Read the code and form your own opinions. * **Optional Asset Processing:** Not all Bevy Apps (or Bevy App developers) need / want asset preprocessing. Processing increases the complexity of the development environment by introducing things like meta files, imported asset storage, running processors in the background, waiting for processing to finish, etc. Distill _requires_ preprocessing to work. With Bevy Asset V2 processing is fully opt-in. The AssetServer isn't directly aware of asset processors at all. AssetLoaders only care about converting bytes to runtime Assets ... they don't know or care if the bytes were pre-processed or not. Processing is "elegantly" (forgive my self-congratulatory phrasing) layered on top and builds on the existing Asset system primitives. * **Direct Filesystem Access to Processed Asset State:** Distill stores processed assets in a database. This makes debugging / inspecting the processed outputs harder (either requires special tooling to query the database or they need to be "deployed" to be inspected). Bevy Asset V2, on the other hand, stores processed assets in the filesystem (by default ... this is configurable). This makes interacting with the processed state more natural. Note that both Godot and Unity's new asset system store processed assets in the filesystem. * **Portability**: Because Distill's processor uses lmdb and RPC networking, it cannot be run on certain platforms (ex: lmdb is a non-rust dependency that cannot run on the web, some platforms don't support running network servers). Bevy should be able to process assets everywhere (ex: run the Bevy Editor on the web, compile + process shaders on mobile, etc). Distill does partially mitigate this problem by supporting "streaming" assets via the RPC protocol, but this is not a full solve from my perspective. And Bevy Asset V2 can (in theory) also stream assets (without requiring RPC, although this isn't implemented yet) Note that I _do_ still think Distill would be a solid asset system for Bevy. But I think the approach in this PR is a better solve for Bevy's specific "asset system requirements". ### Doesn't async-fs just shim requests to "sync" `std::fs`? What is the point? "True async file io" has limited / spotty platform support. async-fs (and the rust async ecosystem generally ... ex Tokio) currently use async wrappers over std::fs that offload blocking requests to separate threads. This may feel unsatisfying, but it _does_ still provide value because it prevents our task pools from blocking on file system operations (which would prevent progress when there are many tasks to do, but all threads in a pool are currently blocking on file system ops). Additionally, using async APIs for our AssetReaders and AssetWriters also provides value because we can later add support for "true async file io" for platforms that support it. _And_ we can implement other "true async io" asset backends (such as networked asset io). ## Draft TODO - [x] Fill in missing filesystem event APIs: file removed event (which is expressed as dangling RenameFrom events in some cases), file/folder renamed event - [x] Assets without loaders are not moved to the processed folder. This breaks things like referenced `.bin` files for GLTFs. This should be configurable per-non-asset-type. - [x] Initial implementation of Reflect and FromReflect for Handle. The "deserialization" parity bar is low here as this only worked with static UUIDs in the old impl ... this is a non-trivial problem. Either we add a Handle::AssetPath variant that gets "upgraded" to a strong handle on scene load or we use a separate AssetRef type for Bevy scenes (which is converted to a runtime Handle on load). This deserves its own discussion in a different pr. - [x] Populate read_asset_bytes hash when run by the processor (a bit of a special case .. when run by the processor the processed meta will contain the hash so we don't need to compute it on the spot, but we don't want/need to read the meta when run by the main AssetServer) - [x] Delay hot reloading: currently filesystem events are handled immediately, which creates timing issues in some cases. For example hot reloading images can sometimes break because the image isn't finished writing. We should add a delay, likely similar to the [implementation in this PR](https://github.com/bevyengine/bevy/pull/8503). - [x] Port old platform-specific AssetIo implementations to the new AssetReader interface (currently missing Android and web) - [x] Resolve on_loaded unsafety (either by removing the API entirely or removing the unsafe) - [x] Runtime loader setting overrides - [x] Remove remaining unwraps that should be error-handled. There are number of TODOs here - [x] Pretty AssetPath Display impl - [x] Document more APIs - [x] Resolve spurious "reloading because it has changed" events (to repro run load_gltf with `processed_dev()`) - [x] load_dependency hot reloading currently only works for processed assets. If processing is disabled, load_dependency changes are not hot reloaded. - [x] Replace AssetInfo dependency load/fail counters with `loading_dependencies: HashSet<UntypedAssetId>` to prevent reloads from (potentially) breaking counters. Storing this will also enable "dependency reloaded" events (see [Next Steps](#next-steps)) - [x] Re-add filesystem watcher cargo feature gate (currently it is not optional) - [ ] Migration Guide - [ ] Changelog ## Followup TODO - [ ] Replace "eager unchanged processed asset loading" behavior with "don't returned unchanged processed asset until dependencies have been checked". - [ ] Add true `Ignore` AssetAction that does not copy the asset to the imported_assets folder. - [ ] Finish "live asset unloading" (ex: free up CPU asset memory after uploading an image to the GPU), rethink RenderAssets, and port renderer features. The `Assets` collection uses `Option<T>` for asset storage to support its removal. (1) the Option might not actually be necessary ... might be able to just remove from the collection entirely (2) need to finalize removal apis - [ ] Try replacing the "channel based" asset id recycling with something a bit more efficient (ex: we might be able to use raw atomic ints with some cleverness) - [ ] Consider adding UUIDs to processed assets (scoped just to helping identify moved assets ... not exposed to load queries ... see [Next Steps](#next-steps)) - [ ] Store "last modified" source asset and meta timestamps in processed meta files to enable skipping expensive hashing when the file wasn't changed - [ ] Fix "slow loop" handle drop fix - [ ] Migrate to TypeName - [x] Handle "loader preregistration". See #9429 ## Next Steps * **Configurable per-type defaults for AssetMeta**: It should be possible to add configuration like "all png image meta should default to using nearest sampling" (currently this hard-coded per-loader/processor Settings::default() impls). Also see the "Folder Meta" bullet point. * **Avoid Reprocessing on Asset Renames / Moves**: See the "canonical asset ids" discussion in [Open Questions](#open-questions) and the relevant bullet point in [Draft TODO](#draft-todo). Even without canonical ids, folder renames could avoid reprocessing in some cases. * **Multiple Asset Sources**: Expand AssetPath to support "asset source names" and support multiple AssetReaders in the asset server (ex: `webserver://some_path/image.png` backed by an Http webserver AssetReader). The "default" asset reader would use normal `some_path/image.png` paths. Ideally this works in combination with multiple AssetWatchers for hot-reloading * **Stable Type Names**: this pr removes the TypeUuid requirement from assets in favor of `std::any::type_name`. This makes defining assets easier (no need to generate a new uuid / use weird proc macro syntax). It also makes reading meta files easier (because things have "friendly names"). We also use type names for components in scene files. If they are good enough for components, they are good enough for assets. And consistency across Bevy pillars is desirable. However, `std::any::type_name` is not guaranteed to be stable (although in practice it is). We've developed a [stable type path](https://github.com/bevyengine/bevy/pull/7184) to resolve this, which should be adopted when it is ready. * **Command Line Interface**: It should be possible to run the asset processor in a separate process from the command line. This will also require building a network-server-backed AssetReader to communicate between the app and the processor. We've been planning to build a "bevy cli" for awhile. This seems like a good excuse to build it. * **Asset Packing**: This is largely an additive feature, so it made sense to me to punt this until we've laid the foundations in this PR. * **Per-Platform Processed Assets**: It should be possible to generate assets for multiple platforms by supporting multiple "processor profiles" per asset (ex: compress with format X on PC and Y on iOS). I think there should probably be arbitrary "profiles" (which can be separate from actual platforms), which are then assigned to a given platform when generating the final asset distribution for that platform. Ex: maybe devs want a "Mobile" profile that is shared between iOS and Android. Or a "LowEnd" profile shared between web and mobile. * **Versioning and Migrations**: Assets, Loaders, Savers, and Processors need to have versions to determine if their schema is valid. If an asset / loader version is incompatible with the current version expected at runtime, the processor should be able to migrate them. I think we should try using Bevy Reflect for this, as it would allow us to load the old version as a dynamic Reflect type without actually having the old Rust type. It would also allow us to define "patches" to migrate between versions (Bevy Reflect devs are currently working on patching). The `.meta` file already has its own format version. Migrating that to new versions should also be possible. * **Real Copy-on-write AssetPaths**: Rust's actual Cow (clone-on-write type) currently used by AssetPath can still result in String clones that aren't actually necessary (cloning an Owned Cow clones the contents). Bevy's asset system requires cloning AssetPaths in a number of places, which result in actual clones of the internal Strings. This is not efficient. AssetPath internals should be reworked to exhibit truer cow-like-behavior that reduces String clones to the absolute minimum. * **Consider processor-less processing**: In theory the AssetServer could run processors "inline" even if the background AssetProcessor is disabled. If we decide this is actually desirable, we could add this. But I don't think its a priority in the short or medium term. * **Pre-emptive dependency loading**: We could encode dependencies in processed meta files, which could then be used by the Asset Server to kick of dependency loads as early as possible (prior to starting the actual asset load). Is this desirable? How much time would this save in practice? * **Optimize Processor With UntypedAssetIds**: The processor exclusively uses AssetPath to identify assets currently. It might be possible to swap these out for UntypedAssetIds in some places, which are smaller / cheaper to hash and compare. * **One to Many Asset Processing**: An asset source file that produces many assets currently must be processed into a single "processed" asset source. If labeled assets can be written separately they can each have their own configured savers _and_ they could be loaded more granularly. Definitely worth exploring! * **Automatically Track "Runtime-only" Asset Dependencies**: Right now, tracking "created at runtime" asset dependencies requires adding them via `asset_server.load_asset(StandardMaterial::default())`. I think with some cleverness we could also do this for `materials.add(StandardMaterial::default())`, making tracking work "everywhere". There are challenges here relating to change detection / ensuring the server is made aware of dependency changes. This could be expensive in some cases. * **"Dependency Changed" events**: Some assets have runtime artifacts that need to be re-generated when one of their dependencies change (ex: regenerate a material's bind group when a Texture needs to change). We are generating the dependency graph so we can definitely produce these events. Buuuuut generating these events will have a cost / they could be high frequency for some assets, so we might want this to be opt-in for specific cases. * **Investigate Storing More Information In Handles**: Handles can now store arbitrary information, which makes it cheaper and easier to access. How much should we move into them? Canonical asset load states (via atomics)? (`handle.is_loaded()` would be very cool). Should we store the entire asset and remove the `Assets<T>` collection? (`Arc<RwLock<Option<Image>>>`?) * **Support processing and loading files without extensions**: This is a pretty arbitrary restriction and could be supported with very minimal changes. * **Folder Meta**: It would be nice if we could define per folder processor configuration defaults (likely in a `.meta` or `.folder_meta` file). Things like "default to linear filtering for all Images in this folder". * **Replace async_broadcast with event-listener?** This might be approximately drop-in for some uses and it feels more light weight * **Support Running the AssetProcessor on the Web**: Most of the hard work is done here, but there are some easy straggling TODOs (make the transaction log an interface instead of a direct file writer so we can write a web storage backend, implement an AssetReader/AssetWriter that reads/writes to something like LocalStorage). * **Consider identifying and preventing circular dependencies**: This is especially important for "processor dependencies", as processing will silently never finish in these cases. * **Built-in/Inlined Asset Hot Reloading**: This PR regresses "built-in/inlined" asset hot reloading (previously provided by the DebugAssetServer). I'm intentionally punting this because I think it can be cleanly implemented with "multiple asset sources" by registering a "debug asset source" (ex: `debug://bevy_pbr/src/render/pbr.wgsl` asset paths) in combination with an AssetWatcher for that asset source and support for "manually loading pats with asset bytes instead of AssetReaders". The old DebugAssetServer was quite nasty and I'd love to avoid that hackery going forward. * **Investigate ways to remove double-parsing meta files**: Parsing meta files currently involves parsing once with "minimal" versions of the meta file to extract the type name of the loader/processor config, then parsing again to parse the "full" meta. This is suboptimal. We should be able to define custom deserializers that (1) assume the loader/processor type name comes first (2) dynamically looks up the loader/processor registrations to deserialize settings in-line (similar to components in the bevy scene format). Another alternative: deserialize as dynamic Reflect objects and then convert. * **More runtime loading configuration**: Support using the Handle type as a hint to select an asset loader (instead of relying on AssetPath extensions) * **More high level Processor trait implementations**: For example, it might be worth adding support for arbitrary chains of "asset transforms" that modify an in-memory asset representation between loading and saving. (ex: load a Mesh, run a `subdivide_mesh` transform, followed by a `flip_normals` transform, then save the mesh to an efficient compressed format). * **Bevy Scene Handle Deserialization**: (see the relevant [Draft TODO item](#draft-todo) for context) * **Explore High Level Load Interfaces**: See [this discussion](#discuss-on_loaded-high-level-interface) for one prototype. * **Asset Streaming**: It would be great if we could stream Assets (ex: stream a long video file piece by piece) * **ID Exchanging**: In this PR Asset Handles/AssetIds are bigger than they need to be because they have a Uuid enum variant. If we implement an "id exchanging" system that trades Uuids for "efficient runtime ids", we can cut down on the size of AssetIds, making them more efficient. This has some open design questions, such as how to spawn entities with "default" handle values (as these wouldn't have access to the exchange api in the current system). * **Asset Path Fixup Tooling**: Assets that inline asset paths inside them will break when an asset moves. The asset system provides the functionality to detect when paths break. We should build a framework that enables formats to define "path migrations". This is especially important for scene files. For editor-generated files, we should also consider using UUIDs (see other bullet point) to avoid the need to migrate in these cases. --------- Co-authored-by: BeastLe9enD <beastle9end@outlook.de> Co-authored-by: Mike <mike.hsu@gmail.com> Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com>
2023-09-07 02:07:27 +00:00
description = "Implements a custom AssetReader"
category = "Assets"
wasm = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[[example]]
name = "hot_asset_reloading"
path = "examples/asset/hot_asset_reloading.rs"
doc-scrape-examples = true
Multiple Asset Sources (#9885) This adds support for **Multiple Asset Sources**. You can now register a named `AssetSource`, which you can load assets from like you normally would: ```rust let shader: Handle<Shader> = asset_server.load("custom_source://path/to/shader.wgsl"); ``` Notice that `AssetPath` now supports `some_source://` syntax. This can now be accessed through the `asset_path.source()` accessor. Asset source names _are not required_. If one is not specified, the default asset source will be used: ```rust let shader: Handle<Shader> = asset_server.load("path/to/shader.wgsl"); ``` The behavior of the default asset source has not changed. Ex: the `assets` folder is still the default. As referenced in #9714 ## Why? **Multiple Asset Sources** enables a number of often-asked-for scenarios: * **Loading some assets from other locations on disk**: you could create a `config` asset source that reads from the OS-default config folder (not implemented in this PR) * **Loading some assets from a remote server**: you could register a new `remote` asset source that reads some assets from a remote http server (not implemented in this PR) * **Improved "Binary Embedded" Assets**: we can use this system for "embedded-in-binary assets", which allows us to replace the old `load_internal_asset!` approach, which couldn't support asset processing, didn't support hot-reloading _well_, and didn't make embedded assets accessible to the `AssetServer` (implemented in this pr) ## Adding New Asset Sources An `AssetSource` is "just" a collection of `AssetReader`, `AssetWriter`, and `AssetWatcher` entries. You can configure new asset sources like this: ```rust app.register_asset_source( "other", AssetSource::build() .with_reader(|| Box::new(FileAssetReader::new("other"))) ) ) ``` Note that `AssetSource` construction _must_ be repeatable, which is why a closure is accepted. `AssetSourceBuilder` supports `with_reader`, `with_writer`, `with_watcher`, `with_processed_reader`, `with_processed_writer`, and `with_processed_watcher`. Note that the "asset source" system replaces the old "asset providers" system. ## Processing Multiple Sources The `AssetProcessor` now supports multiple asset sources! Processed assets can refer to assets in other sources and everything "just works". Each `AssetSource` defines an unprocessed and processed `AssetReader` / `AssetWriter`. Currently this is all or nothing for a given `AssetSource`. A given source is either processed or it is not. Later we might want to add support for "lazy asset processing", where an `AssetSource` (such as a remote server) can be configured to only process assets that are directly referenced by local assets (in order to save local disk space and avoid doing extra work). ## A new `AssetSource`: `embedded` One of the big features motivating **Multiple Asset Sources** was improving our "embedded-in-binary" asset loading. To prove out the **Multiple Asset Sources** implementation, I chose to build a new `embedded` `AssetSource`, which replaces the old `load_interal_asset!` system. The old `load_internal_asset!` approach had a number of issues: * The `AssetServer` was not aware of (or capable of loading) internal assets. * Because internal assets weren't visible to the `AssetServer`, they could not be processed (or used by assets that are processed). This would prevent things "preprocessing shaders that depend on built in Bevy shaders", which is something we desperately need to start doing. * Each "internal asset" needed a UUID to be defined in-code to reference it. This was very manual and toilsome. The new `embedded` `AssetSource` enables the following pattern: ```rust // Called in `crates/bevy_pbr/src/render/mesh.rs` embedded_asset!(app, "mesh.wgsl"); // later in the app let shader: Handle<Shader> = asset_server.load("embedded://bevy_pbr/render/mesh.wgsl"); ``` Notice that this always treats the crate name as the "root path", and it trims out the `src` path for brevity. This is generally predictable, but if you need to debug you can use the new `embedded_path!` macro to get a `PathBuf` that matches the one used by `embedded_asset`. You can also reference embedded assets in arbitrary assets, such as WGSL shaders: ```rust #import "embedded://bevy_pbr/render/mesh.wgsl" ``` This also makes `embedded` assets go through the "normal" asset lifecycle. They are only loaded when they are actually used! We are also discussing implicitly converting asset paths to/from shader modules, so in the future (not in this PR) you might be able to load it like this: ```rust #import bevy_pbr::render::mesh::Vertex ``` Compare that to the old system! ```rust pub const MESH_SHADER_HANDLE: Handle<Shader> = Handle::weak_from_u128(3252377289100772450); load_internal_asset!(app, MESH_SHADER_HANDLE, "mesh.wgsl", Shader::from_wgsl); // The mesh asset is the _only_ accessible via MESH_SHADER_HANDLE and _cannot_ be loaded via the AssetServer. ``` ## Hot Reloading `embedded` You can enable `embedded` hot reloading by enabling the `embedded_watcher` cargo feature: ``` cargo run --features=embedded_watcher ``` ## Improved Hot Reloading Workflow First: the `filesystem_watcher` cargo feature has been renamed to `file_watcher` for brevity (and to match the `FileAssetReader` naming convention). More importantly, hot asset reloading is no longer configured in-code by default. If you enable any asset watcher feature (such as `file_watcher` or `rust_source_watcher`), asset watching will be automatically enabled. This removes the need to _also_ enable hot reloading in your app code. That means you can replace this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::default().watch_for_changes())) ``` with this: ```rust app.add_plugins(DefaultPlugins) ``` If you want to hot reload assets in your app during development, just run your app like this: ``` cargo run --features=file_watcher ``` This means you can use the same code for development and deployment! To deploy an app, just don't include the watcher feature ``` cargo build --release ``` My intent is to move to this approach for pretty much all dev workflows. In a future PR I would like to replace `AssetMode::ProcessedDev` with a `runtime-processor` cargo feature. We could then group all common "dev" cargo features under a single `dev` feature: ```sh # this would enable file_watcher, embedded_watcher, runtime-processor, and more cargo run --features=dev ``` ## AssetMode `AssetPlugin::Unprocessed`, `AssetPlugin::Processed`, and `AssetPlugin::ProcessedDev` have been replaced with an `AssetMode` field on `AssetPlugin`. ```rust // before app.add_plugins(DefaultPlugins.set(AssetPlugin::Processed { /* fields here */ }) // after app.add_plugins(DefaultPlugins.set(AssetPlugin { mode: AssetMode::Processed, ..default() }) ``` This aligns `AssetPlugin` with our other struct-like plugins. The old "source" and "destination" `AssetProvider` fields in the enum variants have been replaced by the "asset source" system. You no longer need to configure the AssetPlugin to "point" to custom asset providers. ## AssetServerMode To improve the implementation of **Multiple Asset Sources**, `AssetServer` was made aware of whether or not it is using "processed" or "unprocessed" assets. You can check that like this: ```rust if asset_server.mode() == AssetServerMode::Processed { /* do something */ } ``` Note that this refactor should also prepare the way for building "one to many processed output files", as it makes the server aware of whether it is loading from processed or unprocessed sources. Meaning we can store and read processed and unprocessed assets differently! ## AssetPath can now refer to folders The "file only" restriction has been removed from `AssetPath`. The `AssetServer::load_folder` API now accepts an `AssetPath` instead of a `Path`, meaning you can load folders from other asset sources! ## Improved AssetPath Parsing AssetPath parsing was reworked to support sources, improve error messages, and to enable parsing with a single pass over the string. `AssetPath::new` was replaced by `AssetPath::parse` and `AssetPath::try_parse`. ## AssetWatcher broken out from AssetReader `AssetReader` is no longer responsible for constructing `AssetWatcher`. This has been moved to `AssetSourceBuilder`. ## Duplicate Event Debouncing Asset V2 already debounced duplicate filesystem events, but this was _input_ events. Multiple input event types can produce the same _output_ `AssetSourceEvent`. Now that we have `embedded_watcher`, which does expensive file io on events, it made sense to debounce output events too, so I added that! This will also benefit the AssetProcessor by preventing integrity checks for duplicate events (and helps keep the noise down in trace logs). ## Next Steps * **Port Built-in Shaders**: Currently the primary (and essentially only) user of `load_interal_asset` in Bevy's source code is "built-in shaders". I chose not to do that in this PR for a few reasons: 1. We need to add the ability to pass shader defs in to shaders via meta files. Some shaders (such as MESH_VIEW_TYPES) need to pass shader def values in that are defined in code. 2. We need to revisit the current shader module naming system. I think we _probably_ want to imply modules from source structure (at least by default). Ideally in a way that can losslessly convert asset paths to/from shader modules (to enable the asset system to resolve modules using the asset server). 3. I want to keep this change set minimal / get this merged first. * **Deprecate `load_internal_asset`**: we can't do that until we do (1) and (2) * **Relative Asset Paths**: This PR significantly increases the need for relative asset paths (which was already pretty high). Currently when loading dependencies, it is assumed to be an absolute path, which means if in an `AssetLoader` you call `context.load("some/path/image.png")` it will assume that is the "default" asset source, _even if the current asset is in a different asset source_. This will cause breakage for AssetLoaders that are not designed to add the current source to whatever paths are being used. AssetLoaders should generally not need to be aware of the name of their current asset source, or need to think about the "current asset source" generally. We should build apis that support relative asset paths and then encourage using relative paths as much as possible (both via api design and docs). Relative paths are also important because they will allow developers to move folders around (even across providers) without reprocessing, provided there is no path breakage.
2023-10-13 23:17:32 +00:00
required-features = ["file_watcher"]
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[package.metadata.example.hot_asset_reloading]
name = "Hot Reloading of Assets"
description = "Demonstrates automatic reloading of assets when modified on disk"
category = "Assets"
wasm = true
Bevy Asset V2 (#8624) # Bevy Asset V2 Proposal ## Why Does Bevy Need A New Asset System? Asset pipelines are a central part of the gamedev process. Bevy's current asset system is missing a number of features that make it non-viable for many classes of gamedev. After plenty of discussions and [a long community feedback period](https://github.com/bevyengine/bevy/discussions/3972), we've identified a number missing features: * **Asset Preprocessing**: it should be possible to "preprocess" / "compile" / "crunch" assets at "development time" rather than when the game starts up. This enables offloading expensive work from deployed apps, faster asset loading, less runtime memory usage, etc. * **Per-Asset Loader Settings**: Individual assets cannot define their own loaders that override the defaults. Additionally, they cannot provide per-asset settings to their loaders. This is a huge limitation, as many asset types don't provide all information necessary for Bevy _inside_ the asset. For example, a raw PNG image says nothing about how it should be sampled (ex: linear vs nearest). * **Asset `.meta` files**: assets should have configuration files stored adjacent to the asset in question, which allows the user to configure asset-type-specific settings. These settings should be accessible during the pre-processing phase. Modifying a `.meta` file should trigger a re-processing / re-load of the asset. It should be possible to configure asset loaders from the meta file. * **Processed Asset Hot Reloading**: Changes to processed assets (or their dependencies) should result in re-processing them and re-loading the results in live Bevy Apps. * **Asset Dependency Tracking**: The current bevy_asset has no good way to wait for asset dependencies to load. It punts this as an exercise for consumers of the loader apis, which is unreasonable and error prone. There should be easy, ergonomic ways to wait for assets to load and block some logic on an asset's entire dependency tree loading. * **Runtime Asset Loading**: it should be (optionally) possible to load arbitrary assets dynamically at runtime. This necessitates being able to deploy and run the asset server alongside Bevy Apps on _all platforms_. For example, we should be able to invoke the shader compiler at runtime, stream scenes from sources like the internet, etc. To keep deployed binaries (and startup times) small, the runtime asset server configuration should be configurable with different settings compared to the "pre processor asset server". * **Multiple Backends**: It should be possible to load assets from arbitrary sources (filesystems, the internet, remote asset serves, etc). * **Asset Packing**: It should be possible to deploy assets in compressed "packs", which makes it easier and more efficient to distribute assets with Bevy Apps. * **Asset Handoff**: It should be possible to hold a "live" asset handle, which correlates to runtime data, without actually holding the asset in memory. Ex: it must be possible to hold a reference to a GPU mesh generated from a "mesh asset" without keeping the mesh data in CPU memory * **Per-Platform Processed Assets**: Different platforms and app distributions have different capabilities and requirements. Some platforms need lower asset resolutions or different asset formats to operate within the hardware constraints of the platform. It should be possible to define per-platform asset processing profiles. And it should be possible to deploy only the assets required for a given platform. These features have architectural implications that are significant enough to require a full rewrite. The current Bevy Asset implementation got us this far, but it can take us no farther. This PR defines a brand new asset system that implements most of these features, while laying the foundations for the remaining features to be built. ## Bevy Asset V2 Here is a quick overview of the features introduced in this PR. * **Asset Preprocessing**: Preprocess assets at development time into more efficient (and configurable) representations * **Dependency Aware**: Dependencies required to process an asset are tracked. If an asset's processed dependency changes, it will be reprocessed * **Hot Reprocessing/Reloading**: detect changes to asset source files, reprocess them if they have changed, and then hot-reload them in Bevy Apps. * **Only Process Changes**: Assets are only re-processed when their source file (or meta file) has changed. This uses hashing and timestamps to avoid processing assets that haven't changed. * **Transactional and Reliable**: Uses write-ahead logging (a technique commonly used by databases) to recover from crashes / forced-exits. Whenever possible it avoids full-reprocessing / only uncompleted transactions will be reprocessed. When the processor is running in parallel with a Bevy App, processor asset writes block Bevy App asset reads. Reading metadata + asset bytes is guaranteed to be transactional / correctly paired. * **Portable / Run anywhere / Database-free**: The processor does not rely on an in-memory database (although it uses some database techniques for reliability). This is important because pretty much all in-memory databases have unsupported platforms or build complications. * **Configure Processor Defaults Per File Type**: You can say "use this processor for all files of this type". * **Custom Processors**: The `Processor` trait is flexible and unopinionated. It can be implemented by downstream plugins. * **LoadAndSave Processors**: Most asset processing scenarios can be expressed as "run AssetLoader A, save the results using AssetSaver X, and then load the result using AssetLoader B". For example, load this png image using `PngImageLoader`, which produces an `Image` asset and then save it using `CompressedImageSaver` (which also produces an `Image` asset, but in a compressed format), which takes an `Image` asset as input. This means if you have an `AssetLoader` for an asset, you are already half way there! It also means that you can share AssetSavers across multiple loaders. Because `CompressedImageSaver` accepts Bevy's generic Image asset as input, it means you can also use it with some future `JpegImageLoader`. * **Loader and Saver Settings**: Asset Loaders and Savers can now define their own settings types, which are passed in as input when an asset is loaded / saved. Each asset can define its own settings. * **Asset `.meta` files**: configure asset loaders, their settings, enable/disable processing, and configure processor settings * **Runtime Asset Dependency Tracking** Runtime asset dependencies (ex: if an asset contains a `Handle<Image>`) are tracked by the asset server. An event is emitted when an asset and all of its dependencies have been loaded * **Unprocessed Asset Loading**: Assets do not require preprocessing. They can be loaded directly. A processed asset is just a "normal" asset with some extra metadata. Asset Loaders don't need to know or care about whether or not an asset was processed. * **Async Asset IO**: Asset readers/writers use async non-blocking interfaces. Note that because Rust doesn't yet support async traits, there is a bit of manual Boxing / Future boilerplate. This will hopefully be removed in the near future when Rust gets async traits. * **Pluggable Asset Readers and Writers**: Arbitrary asset source readers/writers are supported, both by the processor and the asset server. * **Better Asset Handles** * **Single Arc Tree**: Asset Handles now use a single arc tree that represents the lifetime of the asset. This makes their implementation simpler, more efficient, and allows us to cheaply attach metadata to handles. Ex: the AssetPath of a handle is now directly accessible on the handle itself! * **Const Typed Handles**: typed handles can be constructed in a const context. No more weird "const untyped converted to typed at runtime" patterns! * **Handles and Ids are Smaller / Faster To Hash / Compare**: Typed `Handle<T>` is now much smaller in memory and `AssetId<T>` is even smaller. * **Weak Handle Usage Reduction**: In general Handles are now considered to be "strong". Bevy features that previously used "weak `Handle<T>`" have been ported to `AssetId<T>`, which makes it statically clear that the features do not hold strong handles (while retaining strong type information). Currently Handle::Weak still exists, but it is very possible that we can remove that entirely. * **Efficient / Dense Asset Ids**: Assets now have efficient dense runtime asset ids, which means we can avoid expensive hash lookups. Assets are stored in Vecs instead of HashMaps. There are now typed and untyped ids, which means we no longer need to store dynamic type information in the ID for typed handles. "AssetPathId" (which was a nightmare from a performance and correctness standpoint) has been entirely removed in favor of dense ids (which are retrieved for a path on load) * **Direct Asset Loading, with Dependency Tracking**: Assets that are defined at runtime can still have their dependencies tracked by the Asset Server (ex: if you create a material at runtime, you can still wait for its textures to load). This is accomplished via the (currently optional) "asset dependency visitor" trait. This system can also be used to define a set of assets to load, then wait for those assets to load. * **Async folder loading**: Folder loading also uses this system and immediately returns a handle to the LoadedFolder asset, which means folder loading no longer blocks on directory traversals. * **Improved Loader Interface**: Loaders now have a specific "top level asset type", which makes returning the top-level asset simpler and statically typed. * **Basic Image Settings and Processing**: Image assets can now be processed into the gpu-friendly Basic Universal format. The ImageLoader now has a setting to define what format the image should be loaded as. Note that this is just a minimal MVP ... plenty of additional work to do here. To demo this, enable the `basis-universal` feature and turn on asset processing. * **Simpler Audio Play / AudioSink API**: Asset handle providers are cloneable, which means the Audio resource can mint its own handles. This means you can now do `let sink_handle = audio.play(music)` instead of `let sink_handle = audio_sinks.get_handle(audio.play(music))`. Note that this might still be replaced by https://github.com/bevyengine/bevy/pull/8424. **Removed Handle Casting From Engine Features**: Ex: FontAtlases no longer use casting between handle types ## Using The New Asset System ### Normal Unprocessed Asset Loading By default the `AssetPlugin` does not use processing. It behaves pretty much the same way as the old system. If you are defining a custom asset, first derive `Asset`: ```rust #[derive(Asset)] struct Thing { value: String, } ``` Initialize the asset: ```rust app.init_asset:<Thing>() ``` Implement a new `AssetLoader` for it: ```rust #[derive(Default)] struct ThingLoader; #[derive(Serialize, Deserialize, Default)] pub struct ThingSettings { some_setting: bool, } impl AssetLoader for ThingLoader { type Asset = Thing; type Settings = ThingSettings; fn load<'a>( &'a self, reader: &'a mut Reader, settings: &'a ThingSettings, load_context: &'a mut LoadContext, ) -> BoxedFuture<'a, Result<Thing, anyhow::Error>> { Box::pin(async move { let mut bytes = Vec::new(); reader.read_to_end(&mut bytes).await?; // convert bytes to value somehow Ok(Thing { value }) }) } fn extensions(&self) -> &[&str] { &["thing"] } } ``` Note that this interface will get much cleaner once Rust gets support for async traits. `Reader` is an async futures_io::AsyncRead. You can stream bytes as they come in or read them all into a `Vec<u8>`, depending on the context. You can use `let handle = load_context.load(path)` to kick off a dependency load, retrieve a handle, and register the dependency for the asset. Then just register the loader in your Bevy app: ```rust app.init_asset_loader::<ThingLoader>() ``` Now just add your `Thing` asset files into the `assets` folder and load them like this: ```rust fn system(asset_server: Res<AssetServer>) { let handle = Handle<Thing> = asset_server.load("cool.thing"); } ``` You can check load states directly via the asset server: ```rust if asset_server.load_state(&handle) == LoadState::Loaded { } ``` You can also listen for events: ```rust fn system(mut events: EventReader<AssetEvent<Thing>>, handle: Res<SomeThingHandle>) { for event in events.iter() { if event.is_loaded_with_dependencies(&handle) { } } } ``` Note the new `AssetEvent::LoadedWithDependencies`, which only fires when the asset is loaded _and_ all dependencies (and their dependencies) have loaded. Unlike the old asset system, for a given asset path all `Handle<T>` values point to the same underlying Arc. This means Handles can cheaply hold more asset information, such as the AssetPath: ```rust // prints the AssetPath of the handle info!("{:?}", handle.path()) ``` ### Processed Assets Asset processing can be enabled via the `AssetPlugin`. When developing Bevy Apps with processed assets, do this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev())) ``` This runs the `AssetProcessor` in the background with hot-reloading. It reads assets from the `assets` folder, processes them, and writes them to the `.imported_assets` folder. Asset loads in the Bevy App will wait for a processed version of the asset to become available. If an asset in the `assets` folder changes, it will be reprocessed and hot-reloaded in the Bevy App. When deploying processed Bevy apps, do this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::processed())) ``` This does not run the `AssetProcessor` in the background. It behaves like `AssetPlugin::unprocessed()`, but reads assets from `.imported_assets`. When the `AssetProcessor` is running, it will populate sibling `.meta` files for assets in the `assets` folder. Meta files for assets that do not have a processor configured look like this: ```rust ( meta_format_version: "1.0", asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: FromExtension, ), ), ) ``` This is metadata for an image asset. For example, if you have `assets/my_sprite.png`, this could be the metadata stored at `assets/my_sprite.png.meta`. Meta files are totally optional. If no metadata exists, the default settings will be used. In short, this file says "load this asset with the ImageLoader and use the file extension to determine the image type". This type of meta file is supported in all AssetPlugin modes. If in `Unprocessed` mode, the asset (with the meta settings) will be loaded directly. If in `ProcessedDev` mode, the asset file will be copied directly to the `.imported_assets` folder. The meta will also be copied directly to the `.imported_assets` folder, but with one addition: ```rust ( meta_format_version: "1.0", processed_info: Some(( hash: 12415480888597742505, full_hash: 14344495437905856884, process_dependencies: [], )), asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: FromExtension, ), ), ) ``` `processed_info` contains `hash` (a direct hash of the asset and meta bytes), `full_hash` (a hash of `hash` and the hashes of all `process_dependencies`), and `process_dependencies` (the `path` and `full_hash` of every process_dependency). A "process dependency" is an asset dependency that is _directly_ used when processing the asset. Images do not have process dependencies, so this is empty. When the processor is enabled, you can use the `Process` metadata config: ```rust ( meta_format_version: "1.0", asset: Process( processor: "bevy_asset::processor::process::LoadAndSave<bevy_render::texture::image_loader::ImageLoader, bevy_render::texture::compressed_image_saver::CompressedImageSaver>", settings: ( loader_settings: ( format: FromExtension, ), saver_settings: ( generate_mipmaps: true, ), ), ), ) ``` This configures the asset to use the `LoadAndSave` processor, which runs an AssetLoader and feeds the result into an AssetSaver (which saves the given Asset and defines a loader to load it with). (for terseness LoadAndSave will likely get a shorter/friendlier type name when [Stable Type Paths](#7184) lands). `LoadAndSave` is likely to be the most common processor type, but arbitrary processors are supported. `CompressedImageSaver` saves an `Image` in the Basis Universal format and configures the ImageLoader to load it as basis universal. The `AssetProcessor` will read this meta, run it through the LoadAndSave processor, and write the basis-universal version of the image to `.imported_assets`. The final metadata will look like this: ```rust ( meta_format_version: "1.0", processed_info: Some(( hash: 905599590923828066, full_hash: 9948823010183819117, process_dependencies: [], )), asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: Format(Basis), ), ), ) ``` To try basis-universal processing out in Bevy examples, (for example `sprite.rs`), change `add_plugins(DefaultPlugins)` to `add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev()))` and run with the `basis-universal` feature enabled: `cargo run --features=basis-universal --example sprite`. To create a custom processor, there are two main paths: 1. Use the `LoadAndSave` processor with an existing `AssetLoader`. Implement the `AssetSaver` trait, register the processor using `asset_processor.register_processor::<LoadAndSave<ImageLoader, CompressedImageSaver>>(image_saver.into())`. 2. Implement the `Process` trait directly and register it using: `asset_processor.register_processor(thing_processor)`. You can configure default processors for file extensions like this: ```rust asset_processor.set_default_processor::<ThingProcessor>("thing") ``` There is one more metadata type to be aware of: ```rust ( meta_format_version: "1.0", asset: Ignore, ) ``` This will ignore the asset during processing / prevent it from being written to `.imported_assets`. The AssetProcessor stores a transaction log at `.imported_assets/log` and uses it to gracefully recover from unexpected stops. This means you can force-quit the processor (and Bevy Apps running the processor in parallel) at arbitrary times! `.imported_assets` is "local state". It should _not_ be checked into source control. It should also be considered "read only". In practice, you _can_ modify processed assets and processed metadata if you really need to test something. But those modifications will not be represented in the hashes of the assets, so the processed state will be "out of sync" with the source assets. The processor _will not_ fix this for you. Either revert the change after you have tested it, or delete the processed files so they can be re-populated. ## Open Questions There are a number of open questions to be discussed. We should decide if they need to be addressed in this PR and if so, how we will address them: ### Implied Dependencies vs Dependency Enumeration There are currently two ways to populate asset dependencies: * **Implied via AssetLoaders**: if an AssetLoader loads an asset (and retrieves a handle), a dependency is added to the list. * **Explicit via the optional Asset::visit_dependencies**: if `server.load_asset(my_asset)` is called, it will call `my_asset.visit_dependencies`, which will grab dependencies that have been manually defined for the asset via the Asset trait impl (which can be derived). This means that defining explicit dependencies is optional for "loaded assets". And the list of dependencies is always accurate because loaders can only produce Handles if they register dependencies. If an asset was loaded with an AssetLoader, it only uses the implied dependencies. If an asset was created at runtime and added with `asset_server.load_asset(MyAsset)`, it will use `Asset::visit_dependencies`. However this can create a behavior mismatch between loaded assets and equivalent "created at runtime" assets if `Assets::visit_dependencies` doesn't exactly match the dependencies produced by the AssetLoader. This behavior mismatch can be resolved by completely removing "implied loader dependencies" and requiring `Asset::visit_dependencies` to supply dependency data. But this creates two problems: * It makes defining loaded assets harder and more error prone: Devs must remember to manually annotate asset dependencies with `#[dependency]` when deriving `Asset`. For more complicated assets (such as scenes), the derive likely wouldn't be sufficient and a manual `visit_dependencies` impl would be required. * Removes the ability to immediately kick off dependency loads: When AssetLoaders retrieve a Handle, they also immediately kick off an asset load for the handle, which means it can start loading in parallel _before_ the asset finishes loading. For large assets, this could be significant. (although this could be mitigated for processed assets if we store dependencies in the processed meta file and load them ahead of time) ### Eager ProcessorDev Asset Loading I made a controversial call in the interest of fast startup times ("time to first pixel") for the "processor dev mode configuration". When initializing the AssetProcessor, current processed versions of unchanged assets are yielded immediately, even if their dependencies haven't been checked yet for reprocessing. This means that non-current-state-of-filesystem-but-previously-valid assets might be returned to the App first, then hot-reloaded if/when their dependencies change and the asset is reprocessed. Is this behavior desirable? There is largely one alternative: do not yield an asset from the processor to the app until all of its dependencies have been checked for changes. In some common cases (load dependency has not changed since last run) this will increase startup time. The main question is "by how much" and is that slower startup time worth it in the interest of only yielding assets that are true to the current state of the filesystem. Should this be configurable? I'm starting to think we should only yield an asset after its (historical) dependencies have been checked for changes + processed as necessary, but I'm curious what you all think. ### Paths Are Currently The Only Canonical ID / Do We Want Asset UUIDs? In this implementation AssetPaths are the only canonical asset identifier (just like the previous Bevy Asset system and Godot). Moving assets will result in re-scans (and currently reprocessing, although reprocessing can easily be avoided with some changes). Asset renames/moves will break code and assets that rely on specific paths, unless those paths are fixed up. Do we want / need "stable asset uuids"? Introducing them is very possible: 1. Generate a UUID and include it in .meta files 2. Support UUID in AssetPath 3. Generate "asset indices" which are loaded on startup and map UUIDs to paths. 4 (maybe). Consider only supporting UUIDs for processed assets so we can generate quick-to-load indices instead of scanning meta files. The main "pro" is that assets referencing UUIDs don't need to be migrated when a path changes. The main "con" is that UUIDs cannot be "lazily resolved" like paths. They need a full view of all assets to answer the question "does this UUID exist". Which means UUIDs require the AssetProcessor to fully finish startup scans before saying an asset doesnt exist. And they essentially require asset pre-processing to use in apps, because scanning all asset metadata files at runtime to resolve a UUID is not viable for medium-to-large apps. It really requires a pre-generated UUID index, which must be loaded before querying for assets. I personally think this should be investigated in a separate PR. Paths aren't going anywhere ... _everyone_ uses filesystems (and filesystem-like apis) to manage their asset source files. I consider them permanent canonical asset information. Additionally, they behave well for both processed and unprocessed asset modes. Given that Bevy is supporting both, this feels like the right canonical ID to start with. UUIDS (and maybe even other indexed-identifier types) can be added later as necessary. ### Folder / File Naming Conventions All asset processing config currently lives in the `.imported_assets` folder. The processor transaction log is in `.imported_assets/log`. Processed assets are added to `.imported_assets/Default`, which will make migrating to processed asset profiles (ex: a `.imported_assets/Mobile` profile) a non-breaking change. It also allows us to create top-level files like `.imported_assets/log` without it being interpreted as an asset. Meta files currently have a `.meta` suffix. Do we like these names and conventions? ### Should the `AssetPlugin::processed_dev` configuration enable `watch_for_changes` automatically? Currently it does (which I think makes sense), but it does make it the only configuration that enables watch_for_changes by default. ### Discuss on_loaded High Level Interface: This PR includes a very rough "proof of concept" `on_loaded` system adapter that uses the `LoadedWithDependencies` event in combination with `asset_server.load_asset` dependency tracking to support this pattern ```rust fn main() { App::new() .init_asset::<MyAssets>() .add_systems(Update, on_loaded(create_array_texture)) .run(); } #[derive(Asset, Clone)] struct MyAssets { #[dependency] picture_of_my_cat: Handle<Image>, #[dependency] picture_of_my_other_cat: Handle<Image>, } impl FromWorld for ArrayTexture { fn from_world(world: &mut World) -> Self { picture_of_my_cat: server.load("meow.png"), picture_of_my_other_cat: server.load("meeeeeeeow.png"), } } fn spawn_cat(In(my_assets): In<MyAssets>, mut commands: Commands) { commands.spawn(SpriteBundle { texture: my_assets.picture_of_my_cat.clone(), ..default() }); commands.spawn(SpriteBundle { texture: my_assets.picture_of_my_other_cat.clone(), ..default() }); } ``` The implementation is _very_ rough. And it is currently unsafe because `bevy_ecs` doesn't expose some internals to do this safely from inside `bevy_asset`. There are plenty of unanswered questions like: * "do we add a Loadable" derive? (effectively automate the FromWorld implementation above) * Should `MyAssets` even be an Asset? (largely implemented this way because it elegantly builds on `server.load_asset(MyAsset { .. })` dependency tracking). We should think hard about what our ideal API looks like (and if this is a pattern we want to support). Not necessarily something we need to solve in this PR. The current `on_loaded` impl should probably be removed from this PR before merging. ## Clarifying Questions ### What about Assets as Entities? This Bevy Asset V2 proposal implementation initially stored Assets as ECS Entities. Instead of `AssetId<T>` + the `Assets<T>` resource it used `Entity` as the asset id and Asset values were just ECS components. There are plenty of compelling reasons to do this: 1. Easier to inline assets in Bevy Scenes (as they are "just" normal entities + components) 2. More flexible queries: use the power of the ECS to filter assets (ex: `Query<Mesh, With<Tree>>`). 3. Extensible. Users can add arbitrary component data to assets. 4. Things like "component visualization tools" work out of the box to visualize asset data. However Assets as Entities has a ton of caveats right now: * We need to be able to allocate entity ids without a direct World reference (aka rework id allocator in Entities ... i worked around this in my prototypes by just pre allocating big chunks of entities) * We want asset change events in addition to ECS change tracking ... how do we populate them when mutations can come from anywhere? Do we use Changed queries? This would require iterating over the change data for all assets every frame. Is this acceptable or should we implement a new "event based" component change detection option? * Reconciling manually created assets with asset-system managed assets has some nuance (ex: are they "loaded" / do they also have that component metadata?) * "how do we handle "static" / default entity handles" (ties in to the Entity Indices discussion: https://github.com/bevyengine/bevy/discussions/8319). This is necessary for things like "built in" assets and default handles in things like SpriteBundle. * Storing asset information as a component makes it easy to "invalidate" asset state by removing the component (or forcing modifications). Ideally we have ways to lock this down (some combination of Rust type privacy and ECS validation) In practice, how we store and identify assets is a reasonably superficial change (porting off of Assets as Entities and implementing dedicated storage + ids took less than a day). So once we sort out the remaining challenges the flip should be straightforward. Additionally, I do still have "Assets as Entities" in my commit history, so we can reuse that work. I personally think "assets as entities" is a good endgame, but it also doesn't provide _significant_ value at the moment and it certainly isn't ready yet with the current state of things. ### Why not Distill? [Distill](https://github.com/amethyst/distill) is a high quality fully featured asset system built in Rust. It is very natural to ask "why not just use Distill?". It is also worth calling out that for awhile, [we planned on adopting Distill / I signed off on it](https://github.com/bevyengine/bevy/issues/708). However I think Bevy has a number of constraints that make Distill adoption suboptimal: * **Architectural Simplicity:** * Distill's processor requires an in-memory database (lmdb) and RPC networked API (using Cap'n Proto). Each of these introduces API complexity that increases maintenance burden and "code grokability". Ignoring tests, documentation, and examples, Distill has 24,237 lines of Rust code (including generated code for RPC + database interactions). If you ignore generated code, it has 11,499 lines. * Bevy builds the AssetProcessor and AssetServer using pluggable AssetReader/AssetWriter Rust traits with simple io interfaces. They do not necessitate databases or RPC interfaces (although Readers/Writers could use them if that is desired). Bevy Asset V2 (at the time of writing this PR) is 5,384 lines of Rust code (ignoring tests, documentation, and examples). Grain of salt: Distill does have more features currently (ex: Asset Packing, GUIDS, remote-out-of-process asset processor). I do plan to implement these features in Bevy Asset V2 and I personally highly doubt they will meaningfully close the 6115 lines-of-code gap. * This complexity gap (which while illustrated by lines of code, is much bigger than just that) is noteworthy to me. Bevy should be hackable and there are pillars of Distill that are very hard to understand and extend. This is a matter of opinion (and Bevy Asset V2 also has complicated areas), but I think Bevy Asset V2 is much more approachable for the average developer. * Necessary disclaimer: counting lines of code is an extremely rough complexity metric. Read the code and form your own opinions. * **Optional Asset Processing:** Not all Bevy Apps (or Bevy App developers) need / want asset preprocessing. Processing increases the complexity of the development environment by introducing things like meta files, imported asset storage, running processors in the background, waiting for processing to finish, etc. Distill _requires_ preprocessing to work. With Bevy Asset V2 processing is fully opt-in. The AssetServer isn't directly aware of asset processors at all. AssetLoaders only care about converting bytes to runtime Assets ... they don't know or care if the bytes were pre-processed or not. Processing is "elegantly" (forgive my self-congratulatory phrasing) layered on top and builds on the existing Asset system primitives. * **Direct Filesystem Access to Processed Asset State:** Distill stores processed assets in a database. This makes debugging / inspecting the processed outputs harder (either requires special tooling to query the database or they need to be "deployed" to be inspected). Bevy Asset V2, on the other hand, stores processed assets in the filesystem (by default ... this is configurable). This makes interacting with the processed state more natural. Note that both Godot and Unity's new asset system store processed assets in the filesystem. * **Portability**: Because Distill's processor uses lmdb and RPC networking, it cannot be run on certain platforms (ex: lmdb is a non-rust dependency that cannot run on the web, some platforms don't support running network servers). Bevy should be able to process assets everywhere (ex: run the Bevy Editor on the web, compile + process shaders on mobile, etc). Distill does partially mitigate this problem by supporting "streaming" assets via the RPC protocol, but this is not a full solve from my perspective. And Bevy Asset V2 can (in theory) also stream assets (without requiring RPC, although this isn't implemented yet) Note that I _do_ still think Distill would be a solid asset system for Bevy. But I think the approach in this PR is a better solve for Bevy's specific "asset system requirements". ### Doesn't async-fs just shim requests to "sync" `std::fs`? What is the point? "True async file io" has limited / spotty platform support. async-fs (and the rust async ecosystem generally ... ex Tokio) currently use async wrappers over std::fs that offload blocking requests to separate threads. This may feel unsatisfying, but it _does_ still provide value because it prevents our task pools from blocking on file system operations (which would prevent progress when there are many tasks to do, but all threads in a pool are currently blocking on file system ops). Additionally, using async APIs for our AssetReaders and AssetWriters also provides value because we can later add support for "true async file io" for platforms that support it. _And_ we can implement other "true async io" asset backends (such as networked asset io). ## Draft TODO - [x] Fill in missing filesystem event APIs: file removed event (which is expressed as dangling RenameFrom events in some cases), file/folder renamed event - [x] Assets without loaders are not moved to the processed folder. This breaks things like referenced `.bin` files for GLTFs. This should be configurable per-non-asset-type. - [x] Initial implementation of Reflect and FromReflect for Handle. The "deserialization" parity bar is low here as this only worked with static UUIDs in the old impl ... this is a non-trivial problem. Either we add a Handle::AssetPath variant that gets "upgraded" to a strong handle on scene load or we use a separate AssetRef type for Bevy scenes (which is converted to a runtime Handle on load). This deserves its own discussion in a different pr. - [x] Populate read_asset_bytes hash when run by the processor (a bit of a special case .. when run by the processor the processed meta will contain the hash so we don't need to compute it on the spot, but we don't want/need to read the meta when run by the main AssetServer) - [x] Delay hot reloading: currently filesystem events are handled immediately, which creates timing issues in some cases. For example hot reloading images can sometimes break because the image isn't finished writing. We should add a delay, likely similar to the [implementation in this PR](https://github.com/bevyengine/bevy/pull/8503). - [x] Port old platform-specific AssetIo implementations to the new AssetReader interface (currently missing Android and web) - [x] Resolve on_loaded unsafety (either by removing the API entirely or removing the unsafe) - [x] Runtime loader setting overrides - [x] Remove remaining unwraps that should be error-handled. There are number of TODOs here - [x] Pretty AssetPath Display impl - [x] Document more APIs - [x] Resolve spurious "reloading because it has changed" events (to repro run load_gltf with `processed_dev()`) - [x] load_dependency hot reloading currently only works for processed assets. If processing is disabled, load_dependency changes are not hot reloaded. - [x] Replace AssetInfo dependency load/fail counters with `loading_dependencies: HashSet<UntypedAssetId>` to prevent reloads from (potentially) breaking counters. Storing this will also enable "dependency reloaded" events (see [Next Steps](#next-steps)) - [x] Re-add filesystem watcher cargo feature gate (currently it is not optional) - [ ] Migration Guide - [ ] Changelog ## Followup TODO - [ ] Replace "eager unchanged processed asset loading" behavior with "don't returned unchanged processed asset until dependencies have been checked". - [ ] Add true `Ignore` AssetAction that does not copy the asset to the imported_assets folder. - [ ] Finish "live asset unloading" (ex: free up CPU asset memory after uploading an image to the GPU), rethink RenderAssets, and port renderer features. The `Assets` collection uses `Option<T>` for asset storage to support its removal. (1) the Option might not actually be necessary ... might be able to just remove from the collection entirely (2) need to finalize removal apis - [ ] Try replacing the "channel based" asset id recycling with something a bit more efficient (ex: we might be able to use raw atomic ints with some cleverness) - [ ] Consider adding UUIDs to processed assets (scoped just to helping identify moved assets ... not exposed to load queries ... see [Next Steps](#next-steps)) - [ ] Store "last modified" source asset and meta timestamps in processed meta files to enable skipping expensive hashing when the file wasn't changed - [ ] Fix "slow loop" handle drop fix - [ ] Migrate to TypeName - [x] Handle "loader preregistration". See #9429 ## Next Steps * **Configurable per-type defaults for AssetMeta**: It should be possible to add configuration like "all png image meta should default to using nearest sampling" (currently this hard-coded per-loader/processor Settings::default() impls). Also see the "Folder Meta" bullet point. * **Avoid Reprocessing on Asset Renames / Moves**: See the "canonical asset ids" discussion in [Open Questions](#open-questions) and the relevant bullet point in [Draft TODO](#draft-todo). Even without canonical ids, folder renames could avoid reprocessing in some cases. * **Multiple Asset Sources**: Expand AssetPath to support "asset source names" and support multiple AssetReaders in the asset server (ex: `webserver://some_path/image.png` backed by an Http webserver AssetReader). The "default" asset reader would use normal `some_path/image.png` paths. Ideally this works in combination with multiple AssetWatchers for hot-reloading * **Stable Type Names**: this pr removes the TypeUuid requirement from assets in favor of `std::any::type_name`. This makes defining assets easier (no need to generate a new uuid / use weird proc macro syntax). It also makes reading meta files easier (because things have "friendly names"). We also use type names for components in scene files. If they are good enough for components, they are good enough for assets. And consistency across Bevy pillars is desirable. However, `std::any::type_name` is not guaranteed to be stable (although in practice it is). We've developed a [stable type path](https://github.com/bevyengine/bevy/pull/7184) to resolve this, which should be adopted when it is ready. * **Command Line Interface**: It should be possible to run the asset processor in a separate process from the command line. This will also require building a network-server-backed AssetReader to communicate between the app and the processor. We've been planning to build a "bevy cli" for awhile. This seems like a good excuse to build it. * **Asset Packing**: This is largely an additive feature, so it made sense to me to punt this until we've laid the foundations in this PR. * **Per-Platform Processed Assets**: It should be possible to generate assets for multiple platforms by supporting multiple "processor profiles" per asset (ex: compress with format X on PC and Y on iOS). I think there should probably be arbitrary "profiles" (which can be separate from actual platforms), which are then assigned to a given platform when generating the final asset distribution for that platform. Ex: maybe devs want a "Mobile" profile that is shared between iOS and Android. Or a "LowEnd" profile shared between web and mobile. * **Versioning and Migrations**: Assets, Loaders, Savers, and Processors need to have versions to determine if their schema is valid. If an asset / loader version is incompatible with the current version expected at runtime, the processor should be able to migrate them. I think we should try using Bevy Reflect for this, as it would allow us to load the old version as a dynamic Reflect type without actually having the old Rust type. It would also allow us to define "patches" to migrate between versions (Bevy Reflect devs are currently working on patching). The `.meta` file already has its own format version. Migrating that to new versions should also be possible. * **Real Copy-on-write AssetPaths**: Rust's actual Cow (clone-on-write type) currently used by AssetPath can still result in String clones that aren't actually necessary (cloning an Owned Cow clones the contents). Bevy's asset system requires cloning AssetPaths in a number of places, which result in actual clones of the internal Strings. This is not efficient. AssetPath internals should be reworked to exhibit truer cow-like-behavior that reduces String clones to the absolute minimum. * **Consider processor-less processing**: In theory the AssetServer could run processors "inline" even if the background AssetProcessor is disabled. If we decide this is actually desirable, we could add this. But I don't think its a priority in the short or medium term. * **Pre-emptive dependency loading**: We could encode dependencies in processed meta files, which could then be used by the Asset Server to kick of dependency loads as early as possible (prior to starting the actual asset load). Is this desirable? How much time would this save in practice? * **Optimize Processor With UntypedAssetIds**: The processor exclusively uses AssetPath to identify assets currently. It might be possible to swap these out for UntypedAssetIds in some places, which are smaller / cheaper to hash and compare. * **One to Many Asset Processing**: An asset source file that produces many assets currently must be processed into a single "processed" asset source. If labeled assets can be written separately they can each have their own configured savers _and_ they could be loaded more granularly. Definitely worth exploring! * **Automatically Track "Runtime-only" Asset Dependencies**: Right now, tracking "created at runtime" asset dependencies requires adding them via `asset_server.load_asset(StandardMaterial::default())`. I think with some cleverness we could also do this for `materials.add(StandardMaterial::default())`, making tracking work "everywhere". There are challenges here relating to change detection / ensuring the server is made aware of dependency changes. This could be expensive in some cases. * **"Dependency Changed" events**: Some assets have runtime artifacts that need to be re-generated when one of their dependencies change (ex: regenerate a material's bind group when a Texture needs to change). We are generating the dependency graph so we can definitely produce these events. Buuuuut generating these events will have a cost / they could be high frequency for some assets, so we might want this to be opt-in for specific cases. * **Investigate Storing More Information In Handles**: Handles can now store arbitrary information, which makes it cheaper and easier to access. How much should we move into them? Canonical asset load states (via atomics)? (`handle.is_loaded()` would be very cool). Should we store the entire asset and remove the `Assets<T>` collection? (`Arc<RwLock<Option<Image>>>`?) * **Support processing and loading files without extensions**: This is a pretty arbitrary restriction and could be supported with very minimal changes. * **Folder Meta**: It would be nice if we could define per folder processor configuration defaults (likely in a `.meta` or `.folder_meta` file). Things like "default to linear filtering for all Images in this folder". * **Replace async_broadcast with event-listener?** This might be approximately drop-in for some uses and it feels more light weight * **Support Running the AssetProcessor on the Web**: Most of the hard work is done here, but there are some easy straggling TODOs (make the transaction log an interface instead of a direct file writer so we can write a web storage backend, implement an AssetReader/AssetWriter that reads/writes to something like LocalStorage). * **Consider identifying and preventing circular dependencies**: This is especially important for "processor dependencies", as processing will silently never finish in these cases. * **Built-in/Inlined Asset Hot Reloading**: This PR regresses "built-in/inlined" asset hot reloading (previously provided by the DebugAssetServer). I'm intentionally punting this because I think it can be cleanly implemented with "multiple asset sources" by registering a "debug asset source" (ex: `debug://bevy_pbr/src/render/pbr.wgsl` asset paths) in combination with an AssetWatcher for that asset source and support for "manually loading pats with asset bytes instead of AssetReaders". The old DebugAssetServer was quite nasty and I'd love to avoid that hackery going forward. * **Investigate ways to remove double-parsing meta files**: Parsing meta files currently involves parsing once with "minimal" versions of the meta file to extract the type name of the loader/processor config, then parsing again to parse the "full" meta. This is suboptimal. We should be able to define custom deserializers that (1) assume the loader/processor type name comes first (2) dynamically looks up the loader/processor registrations to deserialize settings in-line (similar to components in the bevy scene format). Another alternative: deserialize as dynamic Reflect objects and then convert. * **More runtime loading configuration**: Support using the Handle type as a hint to select an asset loader (instead of relying on AssetPath extensions) * **More high level Processor trait implementations**: For example, it might be worth adding support for arbitrary chains of "asset transforms" that modify an in-memory asset representation between loading and saving. (ex: load a Mesh, run a `subdivide_mesh` transform, followed by a `flip_normals` transform, then save the mesh to an efficient compressed format). * **Bevy Scene Handle Deserialization**: (see the relevant [Draft TODO item](#draft-todo) for context) * **Explore High Level Load Interfaces**: See [this discussion](#discuss-on_loaded-high-level-interface) for one prototype. * **Asset Streaming**: It would be great if we could stream Assets (ex: stream a long video file piece by piece) * **ID Exchanging**: In this PR Asset Handles/AssetIds are bigger than they need to be because they have a Uuid enum variant. If we implement an "id exchanging" system that trades Uuids for "efficient runtime ids", we can cut down on the size of AssetIds, making them more efficient. This has some open design questions, such as how to spawn entities with "default" handle values (as these wouldn't have access to the exchange api in the current system). * **Asset Path Fixup Tooling**: Assets that inline asset paths inside them will break when an asset moves. The asset system provides the functionality to detect when paths break. We should build a framework that enables formats to define "path migrations". This is especially important for scene files. For editor-generated files, we should also consider using UUIDs (see other bullet point) to avoid the need to migrate in these cases. --------- Co-authored-by: BeastLe9enD <beastle9end@outlook.de> Co-authored-by: Mike <mike.hsu@gmail.com> Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com>
2023-09-07 02:07:27 +00:00
[[example]]
name = "asset_processing"
path = "examples/asset/processing/asset_processing.rs"
Bevy Asset V2 (#8624) # Bevy Asset V2 Proposal ## Why Does Bevy Need A New Asset System? Asset pipelines are a central part of the gamedev process. Bevy's current asset system is missing a number of features that make it non-viable for many classes of gamedev. After plenty of discussions and [a long community feedback period](https://github.com/bevyengine/bevy/discussions/3972), we've identified a number missing features: * **Asset Preprocessing**: it should be possible to "preprocess" / "compile" / "crunch" assets at "development time" rather than when the game starts up. This enables offloading expensive work from deployed apps, faster asset loading, less runtime memory usage, etc. * **Per-Asset Loader Settings**: Individual assets cannot define their own loaders that override the defaults. Additionally, they cannot provide per-asset settings to their loaders. This is a huge limitation, as many asset types don't provide all information necessary for Bevy _inside_ the asset. For example, a raw PNG image says nothing about how it should be sampled (ex: linear vs nearest). * **Asset `.meta` files**: assets should have configuration files stored adjacent to the asset in question, which allows the user to configure asset-type-specific settings. These settings should be accessible during the pre-processing phase. Modifying a `.meta` file should trigger a re-processing / re-load of the asset. It should be possible to configure asset loaders from the meta file. * **Processed Asset Hot Reloading**: Changes to processed assets (or their dependencies) should result in re-processing them and re-loading the results in live Bevy Apps. * **Asset Dependency Tracking**: The current bevy_asset has no good way to wait for asset dependencies to load. It punts this as an exercise for consumers of the loader apis, which is unreasonable and error prone. There should be easy, ergonomic ways to wait for assets to load and block some logic on an asset's entire dependency tree loading. * **Runtime Asset Loading**: it should be (optionally) possible to load arbitrary assets dynamically at runtime. This necessitates being able to deploy and run the asset server alongside Bevy Apps on _all platforms_. For example, we should be able to invoke the shader compiler at runtime, stream scenes from sources like the internet, etc. To keep deployed binaries (and startup times) small, the runtime asset server configuration should be configurable with different settings compared to the "pre processor asset server". * **Multiple Backends**: It should be possible to load assets from arbitrary sources (filesystems, the internet, remote asset serves, etc). * **Asset Packing**: It should be possible to deploy assets in compressed "packs", which makes it easier and more efficient to distribute assets with Bevy Apps. * **Asset Handoff**: It should be possible to hold a "live" asset handle, which correlates to runtime data, without actually holding the asset in memory. Ex: it must be possible to hold a reference to a GPU mesh generated from a "mesh asset" without keeping the mesh data in CPU memory * **Per-Platform Processed Assets**: Different platforms and app distributions have different capabilities and requirements. Some platforms need lower asset resolutions or different asset formats to operate within the hardware constraints of the platform. It should be possible to define per-platform asset processing profiles. And it should be possible to deploy only the assets required for a given platform. These features have architectural implications that are significant enough to require a full rewrite. The current Bevy Asset implementation got us this far, but it can take us no farther. This PR defines a brand new asset system that implements most of these features, while laying the foundations for the remaining features to be built. ## Bevy Asset V2 Here is a quick overview of the features introduced in this PR. * **Asset Preprocessing**: Preprocess assets at development time into more efficient (and configurable) representations * **Dependency Aware**: Dependencies required to process an asset are tracked. If an asset's processed dependency changes, it will be reprocessed * **Hot Reprocessing/Reloading**: detect changes to asset source files, reprocess them if they have changed, and then hot-reload them in Bevy Apps. * **Only Process Changes**: Assets are only re-processed when their source file (or meta file) has changed. This uses hashing and timestamps to avoid processing assets that haven't changed. * **Transactional and Reliable**: Uses write-ahead logging (a technique commonly used by databases) to recover from crashes / forced-exits. Whenever possible it avoids full-reprocessing / only uncompleted transactions will be reprocessed. When the processor is running in parallel with a Bevy App, processor asset writes block Bevy App asset reads. Reading metadata + asset bytes is guaranteed to be transactional / correctly paired. * **Portable / Run anywhere / Database-free**: The processor does not rely on an in-memory database (although it uses some database techniques for reliability). This is important because pretty much all in-memory databases have unsupported platforms or build complications. * **Configure Processor Defaults Per File Type**: You can say "use this processor for all files of this type". * **Custom Processors**: The `Processor` trait is flexible and unopinionated. It can be implemented by downstream plugins. * **LoadAndSave Processors**: Most asset processing scenarios can be expressed as "run AssetLoader A, save the results using AssetSaver X, and then load the result using AssetLoader B". For example, load this png image using `PngImageLoader`, which produces an `Image` asset and then save it using `CompressedImageSaver` (which also produces an `Image` asset, but in a compressed format), which takes an `Image` asset as input. This means if you have an `AssetLoader` for an asset, you are already half way there! It also means that you can share AssetSavers across multiple loaders. Because `CompressedImageSaver` accepts Bevy's generic Image asset as input, it means you can also use it with some future `JpegImageLoader`. * **Loader and Saver Settings**: Asset Loaders and Savers can now define their own settings types, which are passed in as input when an asset is loaded / saved. Each asset can define its own settings. * **Asset `.meta` files**: configure asset loaders, their settings, enable/disable processing, and configure processor settings * **Runtime Asset Dependency Tracking** Runtime asset dependencies (ex: if an asset contains a `Handle<Image>`) are tracked by the asset server. An event is emitted when an asset and all of its dependencies have been loaded * **Unprocessed Asset Loading**: Assets do not require preprocessing. They can be loaded directly. A processed asset is just a "normal" asset with some extra metadata. Asset Loaders don't need to know or care about whether or not an asset was processed. * **Async Asset IO**: Asset readers/writers use async non-blocking interfaces. Note that because Rust doesn't yet support async traits, there is a bit of manual Boxing / Future boilerplate. This will hopefully be removed in the near future when Rust gets async traits. * **Pluggable Asset Readers and Writers**: Arbitrary asset source readers/writers are supported, both by the processor and the asset server. * **Better Asset Handles** * **Single Arc Tree**: Asset Handles now use a single arc tree that represents the lifetime of the asset. This makes their implementation simpler, more efficient, and allows us to cheaply attach metadata to handles. Ex: the AssetPath of a handle is now directly accessible on the handle itself! * **Const Typed Handles**: typed handles can be constructed in a const context. No more weird "const untyped converted to typed at runtime" patterns! * **Handles and Ids are Smaller / Faster To Hash / Compare**: Typed `Handle<T>` is now much smaller in memory and `AssetId<T>` is even smaller. * **Weak Handle Usage Reduction**: In general Handles are now considered to be "strong". Bevy features that previously used "weak `Handle<T>`" have been ported to `AssetId<T>`, which makes it statically clear that the features do not hold strong handles (while retaining strong type information). Currently Handle::Weak still exists, but it is very possible that we can remove that entirely. * **Efficient / Dense Asset Ids**: Assets now have efficient dense runtime asset ids, which means we can avoid expensive hash lookups. Assets are stored in Vecs instead of HashMaps. There are now typed and untyped ids, which means we no longer need to store dynamic type information in the ID for typed handles. "AssetPathId" (which was a nightmare from a performance and correctness standpoint) has been entirely removed in favor of dense ids (which are retrieved for a path on load) * **Direct Asset Loading, with Dependency Tracking**: Assets that are defined at runtime can still have their dependencies tracked by the Asset Server (ex: if you create a material at runtime, you can still wait for its textures to load). This is accomplished via the (currently optional) "asset dependency visitor" trait. This system can also be used to define a set of assets to load, then wait for those assets to load. * **Async folder loading**: Folder loading also uses this system and immediately returns a handle to the LoadedFolder asset, which means folder loading no longer blocks on directory traversals. * **Improved Loader Interface**: Loaders now have a specific "top level asset type", which makes returning the top-level asset simpler and statically typed. * **Basic Image Settings and Processing**: Image assets can now be processed into the gpu-friendly Basic Universal format. The ImageLoader now has a setting to define what format the image should be loaded as. Note that this is just a minimal MVP ... plenty of additional work to do here. To demo this, enable the `basis-universal` feature and turn on asset processing. * **Simpler Audio Play / AudioSink API**: Asset handle providers are cloneable, which means the Audio resource can mint its own handles. This means you can now do `let sink_handle = audio.play(music)` instead of `let sink_handle = audio_sinks.get_handle(audio.play(music))`. Note that this might still be replaced by https://github.com/bevyengine/bevy/pull/8424. **Removed Handle Casting From Engine Features**: Ex: FontAtlases no longer use casting between handle types ## Using The New Asset System ### Normal Unprocessed Asset Loading By default the `AssetPlugin` does not use processing. It behaves pretty much the same way as the old system. If you are defining a custom asset, first derive `Asset`: ```rust #[derive(Asset)] struct Thing { value: String, } ``` Initialize the asset: ```rust app.init_asset:<Thing>() ``` Implement a new `AssetLoader` for it: ```rust #[derive(Default)] struct ThingLoader; #[derive(Serialize, Deserialize, Default)] pub struct ThingSettings { some_setting: bool, } impl AssetLoader for ThingLoader { type Asset = Thing; type Settings = ThingSettings; fn load<'a>( &'a self, reader: &'a mut Reader, settings: &'a ThingSettings, load_context: &'a mut LoadContext, ) -> BoxedFuture<'a, Result<Thing, anyhow::Error>> { Box::pin(async move { let mut bytes = Vec::new(); reader.read_to_end(&mut bytes).await?; // convert bytes to value somehow Ok(Thing { value }) }) } fn extensions(&self) -> &[&str] { &["thing"] } } ``` Note that this interface will get much cleaner once Rust gets support for async traits. `Reader` is an async futures_io::AsyncRead. You can stream bytes as they come in or read them all into a `Vec<u8>`, depending on the context. You can use `let handle = load_context.load(path)` to kick off a dependency load, retrieve a handle, and register the dependency for the asset. Then just register the loader in your Bevy app: ```rust app.init_asset_loader::<ThingLoader>() ``` Now just add your `Thing` asset files into the `assets` folder and load them like this: ```rust fn system(asset_server: Res<AssetServer>) { let handle = Handle<Thing> = asset_server.load("cool.thing"); } ``` You can check load states directly via the asset server: ```rust if asset_server.load_state(&handle) == LoadState::Loaded { } ``` You can also listen for events: ```rust fn system(mut events: EventReader<AssetEvent<Thing>>, handle: Res<SomeThingHandle>) { for event in events.iter() { if event.is_loaded_with_dependencies(&handle) { } } } ``` Note the new `AssetEvent::LoadedWithDependencies`, which only fires when the asset is loaded _and_ all dependencies (and their dependencies) have loaded. Unlike the old asset system, for a given asset path all `Handle<T>` values point to the same underlying Arc. This means Handles can cheaply hold more asset information, such as the AssetPath: ```rust // prints the AssetPath of the handle info!("{:?}", handle.path()) ``` ### Processed Assets Asset processing can be enabled via the `AssetPlugin`. When developing Bevy Apps with processed assets, do this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev())) ``` This runs the `AssetProcessor` in the background with hot-reloading. It reads assets from the `assets` folder, processes them, and writes them to the `.imported_assets` folder. Asset loads in the Bevy App will wait for a processed version of the asset to become available. If an asset in the `assets` folder changes, it will be reprocessed and hot-reloaded in the Bevy App. When deploying processed Bevy apps, do this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::processed())) ``` This does not run the `AssetProcessor` in the background. It behaves like `AssetPlugin::unprocessed()`, but reads assets from `.imported_assets`. When the `AssetProcessor` is running, it will populate sibling `.meta` files for assets in the `assets` folder. Meta files for assets that do not have a processor configured look like this: ```rust ( meta_format_version: "1.0", asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: FromExtension, ), ), ) ``` This is metadata for an image asset. For example, if you have `assets/my_sprite.png`, this could be the metadata stored at `assets/my_sprite.png.meta`. Meta files are totally optional. If no metadata exists, the default settings will be used. In short, this file says "load this asset with the ImageLoader and use the file extension to determine the image type". This type of meta file is supported in all AssetPlugin modes. If in `Unprocessed` mode, the asset (with the meta settings) will be loaded directly. If in `ProcessedDev` mode, the asset file will be copied directly to the `.imported_assets` folder. The meta will also be copied directly to the `.imported_assets` folder, but with one addition: ```rust ( meta_format_version: "1.0", processed_info: Some(( hash: 12415480888597742505, full_hash: 14344495437905856884, process_dependencies: [], )), asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: FromExtension, ), ), ) ``` `processed_info` contains `hash` (a direct hash of the asset and meta bytes), `full_hash` (a hash of `hash` and the hashes of all `process_dependencies`), and `process_dependencies` (the `path` and `full_hash` of every process_dependency). A "process dependency" is an asset dependency that is _directly_ used when processing the asset. Images do not have process dependencies, so this is empty. When the processor is enabled, you can use the `Process` metadata config: ```rust ( meta_format_version: "1.0", asset: Process( processor: "bevy_asset::processor::process::LoadAndSave<bevy_render::texture::image_loader::ImageLoader, bevy_render::texture::compressed_image_saver::CompressedImageSaver>", settings: ( loader_settings: ( format: FromExtension, ), saver_settings: ( generate_mipmaps: true, ), ), ), ) ``` This configures the asset to use the `LoadAndSave` processor, which runs an AssetLoader and feeds the result into an AssetSaver (which saves the given Asset and defines a loader to load it with). (for terseness LoadAndSave will likely get a shorter/friendlier type name when [Stable Type Paths](#7184) lands). `LoadAndSave` is likely to be the most common processor type, but arbitrary processors are supported. `CompressedImageSaver` saves an `Image` in the Basis Universal format and configures the ImageLoader to load it as basis universal. The `AssetProcessor` will read this meta, run it through the LoadAndSave processor, and write the basis-universal version of the image to `.imported_assets`. The final metadata will look like this: ```rust ( meta_format_version: "1.0", processed_info: Some(( hash: 905599590923828066, full_hash: 9948823010183819117, process_dependencies: [], )), asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: Format(Basis), ), ), ) ``` To try basis-universal processing out in Bevy examples, (for example `sprite.rs`), change `add_plugins(DefaultPlugins)` to `add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev()))` and run with the `basis-universal` feature enabled: `cargo run --features=basis-universal --example sprite`. To create a custom processor, there are two main paths: 1. Use the `LoadAndSave` processor with an existing `AssetLoader`. Implement the `AssetSaver` trait, register the processor using `asset_processor.register_processor::<LoadAndSave<ImageLoader, CompressedImageSaver>>(image_saver.into())`. 2. Implement the `Process` trait directly and register it using: `asset_processor.register_processor(thing_processor)`. You can configure default processors for file extensions like this: ```rust asset_processor.set_default_processor::<ThingProcessor>("thing") ``` There is one more metadata type to be aware of: ```rust ( meta_format_version: "1.0", asset: Ignore, ) ``` This will ignore the asset during processing / prevent it from being written to `.imported_assets`. The AssetProcessor stores a transaction log at `.imported_assets/log` and uses it to gracefully recover from unexpected stops. This means you can force-quit the processor (and Bevy Apps running the processor in parallel) at arbitrary times! `.imported_assets` is "local state". It should _not_ be checked into source control. It should also be considered "read only". In practice, you _can_ modify processed assets and processed metadata if you really need to test something. But those modifications will not be represented in the hashes of the assets, so the processed state will be "out of sync" with the source assets. The processor _will not_ fix this for you. Either revert the change after you have tested it, or delete the processed files so they can be re-populated. ## Open Questions There are a number of open questions to be discussed. We should decide if they need to be addressed in this PR and if so, how we will address them: ### Implied Dependencies vs Dependency Enumeration There are currently two ways to populate asset dependencies: * **Implied via AssetLoaders**: if an AssetLoader loads an asset (and retrieves a handle), a dependency is added to the list. * **Explicit via the optional Asset::visit_dependencies**: if `server.load_asset(my_asset)` is called, it will call `my_asset.visit_dependencies`, which will grab dependencies that have been manually defined for the asset via the Asset trait impl (which can be derived). This means that defining explicit dependencies is optional for "loaded assets". And the list of dependencies is always accurate because loaders can only produce Handles if they register dependencies. If an asset was loaded with an AssetLoader, it only uses the implied dependencies. If an asset was created at runtime and added with `asset_server.load_asset(MyAsset)`, it will use `Asset::visit_dependencies`. However this can create a behavior mismatch between loaded assets and equivalent "created at runtime" assets if `Assets::visit_dependencies` doesn't exactly match the dependencies produced by the AssetLoader. This behavior mismatch can be resolved by completely removing "implied loader dependencies" and requiring `Asset::visit_dependencies` to supply dependency data. But this creates two problems: * It makes defining loaded assets harder and more error prone: Devs must remember to manually annotate asset dependencies with `#[dependency]` when deriving `Asset`. For more complicated assets (such as scenes), the derive likely wouldn't be sufficient and a manual `visit_dependencies` impl would be required. * Removes the ability to immediately kick off dependency loads: When AssetLoaders retrieve a Handle, they also immediately kick off an asset load for the handle, which means it can start loading in parallel _before_ the asset finishes loading. For large assets, this could be significant. (although this could be mitigated for processed assets if we store dependencies in the processed meta file and load them ahead of time) ### Eager ProcessorDev Asset Loading I made a controversial call in the interest of fast startup times ("time to first pixel") for the "processor dev mode configuration". When initializing the AssetProcessor, current processed versions of unchanged assets are yielded immediately, even if their dependencies haven't been checked yet for reprocessing. This means that non-current-state-of-filesystem-but-previously-valid assets might be returned to the App first, then hot-reloaded if/when their dependencies change and the asset is reprocessed. Is this behavior desirable? There is largely one alternative: do not yield an asset from the processor to the app until all of its dependencies have been checked for changes. In some common cases (load dependency has not changed since last run) this will increase startup time. The main question is "by how much" and is that slower startup time worth it in the interest of only yielding assets that are true to the current state of the filesystem. Should this be configurable? I'm starting to think we should only yield an asset after its (historical) dependencies have been checked for changes + processed as necessary, but I'm curious what you all think. ### Paths Are Currently The Only Canonical ID / Do We Want Asset UUIDs? In this implementation AssetPaths are the only canonical asset identifier (just like the previous Bevy Asset system and Godot). Moving assets will result in re-scans (and currently reprocessing, although reprocessing can easily be avoided with some changes). Asset renames/moves will break code and assets that rely on specific paths, unless those paths are fixed up. Do we want / need "stable asset uuids"? Introducing them is very possible: 1. Generate a UUID and include it in .meta files 2. Support UUID in AssetPath 3. Generate "asset indices" which are loaded on startup and map UUIDs to paths. 4 (maybe). Consider only supporting UUIDs for processed assets so we can generate quick-to-load indices instead of scanning meta files. The main "pro" is that assets referencing UUIDs don't need to be migrated when a path changes. The main "con" is that UUIDs cannot be "lazily resolved" like paths. They need a full view of all assets to answer the question "does this UUID exist". Which means UUIDs require the AssetProcessor to fully finish startup scans before saying an asset doesnt exist. And they essentially require asset pre-processing to use in apps, because scanning all asset metadata files at runtime to resolve a UUID is not viable for medium-to-large apps. It really requires a pre-generated UUID index, which must be loaded before querying for assets. I personally think this should be investigated in a separate PR. Paths aren't going anywhere ... _everyone_ uses filesystems (and filesystem-like apis) to manage their asset source files. I consider them permanent canonical asset information. Additionally, they behave well for both processed and unprocessed asset modes. Given that Bevy is supporting both, this feels like the right canonical ID to start with. UUIDS (and maybe even other indexed-identifier types) can be added later as necessary. ### Folder / File Naming Conventions All asset processing config currently lives in the `.imported_assets` folder. The processor transaction log is in `.imported_assets/log`. Processed assets are added to `.imported_assets/Default`, which will make migrating to processed asset profiles (ex: a `.imported_assets/Mobile` profile) a non-breaking change. It also allows us to create top-level files like `.imported_assets/log` without it being interpreted as an asset. Meta files currently have a `.meta` suffix. Do we like these names and conventions? ### Should the `AssetPlugin::processed_dev` configuration enable `watch_for_changes` automatically? Currently it does (which I think makes sense), but it does make it the only configuration that enables watch_for_changes by default. ### Discuss on_loaded High Level Interface: This PR includes a very rough "proof of concept" `on_loaded` system adapter that uses the `LoadedWithDependencies` event in combination with `asset_server.load_asset` dependency tracking to support this pattern ```rust fn main() { App::new() .init_asset::<MyAssets>() .add_systems(Update, on_loaded(create_array_texture)) .run(); } #[derive(Asset, Clone)] struct MyAssets { #[dependency] picture_of_my_cat: Handle<Image>, #[dependency] picture_of_my_other_cat: Handle<Image>, } impl FromWorld for ArrayTexture { fn from_world(world: &mut World) -> Self { picture_of_my_cat: server.load("meow.png"), picture_of_my_other_cat: server.load("meeeeeeeow.png"), } } fn spawn_cat(In(my_assets): In<MyAssets>, mut commands: Commands) { commands.spawn(SpriteBundle { texture: my_assets.picture_of_my_cat.clone(), ..default() }); commands.spawn(SpriteBundle { texture: my_assets.picture_of_my_other_cat.clone(), ..default() }); } ``` The implementation is _very_ rough. And it is currently unsafe because `bevy_ecs` doesn't expose some internals to do this safely from inside `bevy_asset`. There are plenty of unanswered questions like: * "do we add a Loadable" derive? (effectively automate the FromWorld implementation above) * Should `MyAssets` even be an Asset? (largely implemented this way because it elegantly builds on `server.load_asset(MyAsset { .. })` dependency tracking). We should think hard about what our ideal API looks like (and if this is a pattern we want to support). Not necessarily something we need to solve in this PR. The current `on_loaded` impl should probably be removed from this PR before merging. ## Clarifying Questions ### What about Assets as Entities? This Bevy Asset V2 proposal implementation initially stored Assets as ECS Entities. Instead of `AssetId<T>` + the `Assets<T>` resource it used `Entity` as the asset id and Asset values were just ECS components. There are plenty of compelling reasons to do this: 1. Easier to inline assets in Bevy Scenes (as they are "just" normal entities + components) 2. More flexible queries: use the power of the ECS to filter assets (ex: `Query<Mesh, With<Tree>>`). 3. Extensible. Users can add arbitrary component data to assets. 4. Things like "component visualization tools" work out of the box to visualize asset data. However Assets as Entities has a ton of caveats right now: * We need to be able to allocate entity ids without a direct World reference (aka rework id allocator in Entities ... i worked around this in my prototypes by just pre allocating big chunks of entities) * We want asset change events in addition to ECS change tracking ... how do we populate them when mutations can come from anywhere? Do we use Changed queries? This would require iterating over the change data for all assets every frame. Is this acceptable or should we implement a new "event based" component change detection option? * Reconciling manually created assets with asset-system managed assets has some nuance (ex: are they "loaded" / do they also have that component metadata?) * "how do we handle "static" / default entity handles" (ties in to the Entity Indices discussion: https://github.com/bevyengine/bevy/discussions/8319). This is necessary for things like "built in" assets and default handles in things like SpriteBundle. * Storing asset information as a component makes it easy to "invalidate" asset state by removing the component (or forcing modifications). Ideally we have ways to lock this down (some combination of Rust type privacy and ECS validation) In practice, how we store and identify assets is a reasonably superficial change (porting off of Assets as Entities and implementing dedicated storage + ids took less than a day). So once we sort out the remaining challenges the flip should be straightforward. Additionally, I do still have "Assets as Entities" in my commit history, so we can reuse that work. I personally think "assets as entities" is a good endgame, but it also doesn't provide _significant_ value at the moment and it certainly isn't ready yet with the current state of things. ### Why not Distill? [Distill](https://github.com/amethyst/distill) is a high quality fully featured asset system built in Rust. It is very natural to ask "why not just use Distill?". It is also worth calling out that for awhile, [we planned on adopting Distill / I signed off on it](https://github.com/bevyengine/bevy/issues/708). However I think Bevy has a number of constraints that make Distill adoption suboptimal: * **Architectural Simplicity:** * Distill's processor requires an in-memory database (lmdb) and RPC networked API (using Cap'n Proto). Each of these introduces API complexity that increases maintenance burden and "code grokability". Ignoring tests, documentation, and examples, Distill has 24,237 lines of Rust code (including generated code for RPC + database interactions). If you ignore generated code, it has 11,499 lines. * Bevy builds the AssetProcessor and AssetServer using pluggable AssetReader/AssetWriter Rust traits with simple io interfaces. They do not necessitate databases or RPC interfaces (although Readers/Writers could use them if that is desired). Bevy Asset V2 (at the time of writing this PR) is 5,384 lines of Rust code (ignoring tests, documentation, and examples). Grain of salt: Distill does have more features currently (ex: Asset Packing, GUIDS, remote-out-of-process asset processor). I do plan to implement these features in Bevy Asset V2 and I personally highly doubt they will meaningfully close the 6115 lines-of-code gap. * This complexity gap (which while illustrated by lines of code, is much bigger than just that) is noteworthy to me. Bevy should be hackable and there are pillars of Distill that are very hard to understand and extend. This is a matter of opinion (and Bevy Asset V2 also has complicated areas), but I think Bevy Asset V2 is much more approachable for the average developer. * Necessary disclaimer: counting lines of code is an extremely rough complexity metric. Read the code and form your own opinions. * **Optional Asset Processing:** Not all Bevy Apps (or Bevy App developers) need / want asset preprocessing. Processing increases the complexity of the development environment by introducing things like meta files, imported asset storage, running processors in the background, waiting for processing to finish, etc. Distill _requires_ preprocessing to work. With Bevy Asset V2 processing is fully opt-in. The AssetServer isn't directly aware of asset processors at all. AssetLoaders only care about converting bytes to runtime Assets ... they don't know or care if the bytes were pre-processed or not. Processing is "elegantly" (forgive my self-congratulatory phrasing) layered on top and builds on the existing Asset system primitives. * **Direct Filesystem Access to Processed Asset State:** Distill stores processed assets in a database. This makes debugging / inspecting the processed outputs harder (either requires special tooling to query the database or they need to be "deployed" to be inspected). Bevy Asset V2, on the other hand, stores processed assets in the filesystem (by default ... this is configurable). This makes interacting with the processed state more natural. Note that both Godot and Unity's new asset system store processed assets in the filesystem. * **Portability**: Because Distill's processor uses lmdb and RPC networking, it cannot be run on certain platforms (ex: lmdb is a non-rust dependency that cannot run on the web, some platforms don't support running network servers). Bevy should be able to process assets everywhere (ex: run the Bevy Editor on the web, compile + process shaders on mobile, etc). Distill does partially mitigate this problem by supporting "streaming" assets via the RPC protocol, but this is not a full solve from my perspective. And Bevy Asset V2 can (in theory) also stream assets (without requiring RPC, although this isn't implemented yet) Note that I _do_ still think Distill would be a solid asset system for Bevy. But I think the approach in this PR is a better solve for Bevy's specific "asset system requirements". ### Doesn't async-fs just shim requests to "sync" `std::fs`? What is the point? "True async file io" has limited / spotty platform support. async-fs (and the rust async ecosystem generally ... ex Tokio) currently use async wrappers over std::fs that offload blocking requests to separate threads. This may feel unsatisfying, but it _does_ still provide value because it prevents our task pools from blocking on file system operations (which would prevent progress when there are many tasks to do, but all threads in a pool are currently blocking on file system ops). Additionally, using async APIs for our AssetReaders and AssetWriters also provides value because we can later add support for "true async file io" for platforms that support it. _And_ we can implement other "true async io" asset backends (such as networked asset io). ## Draft TODO - [x] Fill in missing filesystem event APIs: file removed event (which is expressed as dangling RenameFrom events in some cases), file/folder renamed event - [x] Assets without loaders are not moved to the processed folder. This breaks things like referenced `.bin` files for GLTFs. This should be configurable per-non-asset-type. - [x] Initial implementation of Reflect and FromReflect for Handle. The "deserialization" parity bar is low here as this only worked with static UUIDs in the old impl ... this is a non-trivial problem. Either we add a Handle::AssetPath variant that gets "upgraded" to a strong handle on scene load or we use a separate AssetRef type for Bevy scenes (which is converted to a runtime Handle on load). This deserves its own discussion in a different pr. - [x] Populate read_asset_bytes hash when run by the processor (a bit of a special case .. when run by the processor the processed meta will contain the hash so we don't need to compute it on the spot, but we don't want/need to read the meta when run by the main AssetServer) - [x] Delay hot reloading: currently filesystem events are handled immediately, which creates timing issues in some cases. For example hot reloading images can sometimes break because the image isn't finished writing. We should add a delay, likely similar to the [implementation in this PR](https://github.com/bevyengine/bevy/pull/8503). - [x] Port old platform-specific AssetIo implementations to the new AssetReader interface (currently missing Android and web) - [x] Resolve on_loaded unsafety (either by removing the API entirely or removing the unsafe) - [x] Runtime loader setting overrides - [x] Remove remaining unwraps that should be error-handled. There are number of TODOs here - [x] Pretty AssetPath Display impl - [x] Document more APIs - [x] Resolve spurious "reloading because it has changed" events (to repro run load_gltf with `processed_dev()`) - [x] load_dependency hot reloading currently only works for processed assets. If processing is disabled, load_dependency changes are not hot reloaded. - [x] Replace AssetInfo dependency load/fail counters with `loading_dependencies: HashSet<UntypedAssetId>` to prevent reloads from (potentially) breaking counters. Storing this will also enable "dependency reloaded" events (see [Next Steps](#next-steps)) - [x] Re-add filesystem watcher cargo feature gate (currently it is not optional) - [ ] Migration Guide - [ ] Changelog ## Followup TODO - [ ] Replace "eager unchanged processed asset loading" behavior with "don't returned unchanged processed asset until dependencies have been checked". - [ ] Add true `Ignore` AssetAction that does not copy the asset to the imported_assets folder. - [ ] Finish "live asset unloading" (ex: free up CPU asset memory after uploading an image to the GPU), rethink RenderAssets, and port renderer features. The `Assets` collection uses `Option<T>` for asset storage to support its removal. (1) the Option might not actually be necessary ... might be able to just remove from the collection entirely (2) need to finalize removal apis - [ ] Try replacing the "channel based" asset id recycling with something a bit more efficient (ex: we might be able to use raw atomic ints with some cleverness) - [ ] Consider adding UUIDs to processed assets (scoped just to helping identify moved assets ... not exposed to load queries ... see [Next Steps](#next-steps)) - [ ] Store "last modified" source asset and meta timestamps in processed meta files to enable skipping expensive hashing when the file wasn't changed - [ ] Fix "slow loop" handle drop fix - [ ] Migrate to TypeName - [x] Handle "loader preregistration". See #9429 ## Next Steps * **Configurable per-type defaults for AssetMeta**: It should be possible to add configuration like "all png image meta should default to using nearest sampling" (currently this hard-coded per-loader/processor Settings::default() impls). Also see the "Folder Meta" bullet point. * **Avoid Reprocessing on Asset Renames / Moves**: See the "canonical asset ids" discussion in [Open Questions](#open-questions) and the relevant bullet point in [Draft TODO](#draft-todo). Even without canonical ids, folder renames could avoid reprocessing in some cases. * **Multiple Asset Sources**: Expand AssetPath to support "asset source names" and support multiple AssetReaders in the asset server (ex: `webserver://some_path/image.png` backed by an Http webserver AssetReader). The "default" asset reader would use normal `some_path/image.png` paths. Ideally this works in combination with multiple AssetWatchers for hot-reloading * **Stable Type Names**: this pr removes the TypeUuid requirement from assets in favor of `std::any::type_name`. This makes defining assets easier (no need to generate a new uuid / use weird proc macro syntax). It also makes reading meta files easier (because things have "friendly names"). We also use type names for components in scene files. If they are good enough for components, they are good enough for assets. And consistency across Bevy pillars is desirable. However, `std::any::type_name` is not guaranteed to be stable (although in practice it is). We've developed a [stable type path](https://github.com/bevyengine/bevy/pull/7184) to resolve this, which should be adopted when it is ready. * **Command Line Interface**: It should be possible to run the asset processor in a separate process from the command line. This will also require building a network-server-backed AssetReader to communicate between the app and the processor. We've been planning to build a "bevy cli" for awhile. This seems like a good excuse to build it. * **Asset Packing**: This is largely an additive feature, so it made sense to me to punt this until we've laid the foundations in this PR. * **Per-Platform Processed Assets**: It should be possible to generate assets for multiple platforms by supporting multiple "processor profiles" per asset (ex: compress with format X on PC and Y on iOS). I think there should probably be arbitrary "profiles" (which can be separate from actual platforms), which are then assigned to a given platform when generating the final asset distribution for that platform. Ex: maybe devs want a "Mobile" profile that is shared between iOS and Android. Or a "LowEnd" profile shared between web and mobile. * **Versioning and Migrations**: Assets, Loaders, Savers, and Processors need to have versions to determine if their schema is valid. If an asset / loader version is incompatible with the current version expected at runtime, the processor should be able to migrate them. I think we should try using Bevy Reflect for this, as it would allow us to load the old version as a dynamic Reflect type without actually having the old Rust type. It would also allow us to define "patches" to migrate between versions (Bevy Reflect devs are currently working on patching). The `.meta` file already has its own format version. Migrating that to new versions should also be possible. * **Real Copy-on-write AssetPaths**: Rust's actual Cow (clone-on-write type) currently used by AssetPath can still result in String clones that aren't actually necessary (cloning an Owned Cow clones the contents). Bevy's asset system requires cloning AssetPaths in a number of places, which result in actual clones of the internal Strings. This is not efficient. AssetPath internals should be reworked to exhibit truer cow-like-behavior that reduces String clones to the absolute minimum. * **Consider processor-less processing**: In theory the AssetServer could run processors "inline" even if the background AssetProcessor is disabled. If we decide this is actually desirable, we could add this. But I don't think its a priority in the short or medium term. * **Pre-emptive dependency loading**: We could encode dependencies in processed meta files, which could then be used by the Asset Server to kick of dependency loads as early as possible (prior to starting the actual asset load). Is this desirable? How much time would this save in practice? * **Optimize Processor With UntypedAssetIds**: The processor exclusively uses AssetPath to identify assets currently. It might be possible to swap these out for UntypedAssetIds in some places, which are smaller / cheaper to hash and compare. * **One to Many Asset Processing**: An asset source file that produces many assets currently must be processed into a single "processed" asset source. If labeled assets can be written separately they can each have their own configured savers _and_ they could be loaded more granularly. Definitely worth exploring! * **Automatically Track "Runtime-only" Asset Dependencies**: Right now, tracking "created at runtime" asset dependencies requires adding them via `asset_server.load_asset(StandardMaterial::default())`. I think with some cleverness we could also do this for `materials.add(StandardMaterial::default())`, making tracking work "everywhere". There are challenges here relating to change detection / ensuring the server is made aware of dependency changes. This could be expensive in some cases. * **"Dependency Changed" events**: Some assets have runtime artifacts that need to be re-generated when one of their dependencies change (ex: regenerate a material's bind group when a Texture needs to change). We are generating the dependency graph so we can definitely produce these events. Buuuuut generating these events will have a cost / they could be high frequency for some assets, so we might want this to be opt-in for specific cases. * **Investigate Storing More Information In Handles**: Handles can now store arbitrary information, which makes it cheaper and easier to access. How much should we move into them? Canonical asset load states (via atomics)? (`handle.is_loaded()` would be very cool). Should we store the entire asset and remove the `Assets<T>` collection? (`Arc<RwLock<Option<Image>>>`?) * **Support processing and loading files without extensions**: This is a pretty arbitrary restriction and could be supported with very minimal changes. * **Folder Meta**: It would be nice if we could define per folder processor configuration defaults (likely in a `.meta` or `.folder_meta` file). Things like "default to linear filtering for all Images in this folder". * **Replace async_broadcast with event-listener?** This might be approximately drop-in for some uses and it feels more light weight * **Support Running the AssetProcessor on the Web**: Most of the hard work is done here, but there are some easy straggling TODOs (make the transaction log an interface instead of a direct file writer so we can write a web storage backend, implement an AssetReader/AssetWriter that reads/writes to something like LocalStorage). * **Consider identifying and preventing circular dependencies**: This is especially important for "processor dependencies", as processing will silently never finish in these cases. * **Built-in/Inlined Asset Hot Reloading**: This PR regresses "built-in/inlined" asset hot reloading (previously provided by the DebugAssetServer). I'm intentionally punting this because I think it can be cleanly implemented with "multiple asset sources" by registering a "debug asset source" (ex: `debug://bevy_pbr/src/render/pbr.wgsl` asset paths) in combination with an AssetWatcher for that asset source and support for "manually loading pats with asset bytes instead of AssetReaders". The old DebugAssetServer was quite nasty and I'd love to avoid that hackery going forward. * **Investigate ways to remove double-parsing meta files**: Parsing meta files currently involves parsing once with "minimal" versions of the meta file to extract the type name of the loader/processor config, then parsing again to parse the "full" meta. This is suboptimal. We should be able to define custom deserializers that (1) assume the loader/processor type name comes first (2) dynamically looks up the loader/processor registrations to deserialize settings in-line (similar to components in the bevy scene format). Another alternative: deserialize as dynamic Reflect objects and then convert. * **More runtime loading configuration**: Support using the Handle type as a hint to select an asset loader (instead of relying on AssetPath extensions) * **More high level Processor trait implementations**: For example, it might be worth adding support for arbitrary chains of "asset transforms" that modify an in-memory asset representation between loading and saving. (ex: load a Mesh, run a `subdivide_mesh` transform, followed by a `flip_normals` transform, then save the mesh to an efficient compressed format). * **Bevy Scene Handle Deserialization**: (see the relevant [Draft TODO item](#draft-todo) for context) * **Explore High Level Load Interfaces**: See [this discussion](#discuss-on_loaded-high-level-interface) for one prototype. * **Asset Streaming**: It would be great if we could stream Assets (ex: stream a long video file piece by piece) * **ID Exchanging**: In this PR Asset Handles/AssetIds are bigger than they need to be because they have a Uuid enum variant. If we implement an "id exchanging" system that trades Uuids for "efficient runtime ids", we can cut down on the size of AssetIds, making them more efficient. This has some open design questions, such as how to spawn entities with "default" handle values (as these wouldn't have access to the exchange api in the current system). * **Asset Path Fixup Tooling**: Assets that inline asset paths inside them will break when an asset moves. The asset system provides the functionality to detect when paths break. We should build a framework that enables formats to define "path migrations". This is especially important for scene files. For editor-generated files, we should also consider using UUIDs (see other bullet point) to avoid the need to migrate in these cases. --------- Co-authored-by: BeastLe9enD <beastle9end@outlook.de> Co-authored-by: Mike <mike.hsu@gmail.com> Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com>
2023-09-07 02:07:27 +00:00
doc-scrape-examples = true
required-features = ["file_watcher", "asset_processor"]
Bevy Asset V2 (#8624) # Bevy Asset V2 Proposal ## Why Does Bevy Need A New Asset System? Asset pipelines are a central part of the gamedev process. Bevy's current asset system is missing a number of features that make it non-viable for many classes of gamedev. After plenty of discussions and [a long community feedback period](https://github.com/bevyengine/bevy/discussions/3972), we've identified a number missing features: * **Asset Preprocessing**: it should be possible to "preprocess" / "compile" / "crunch" assets at "development time" rather than when the game starts up. This enables offloading expensive work from deployed apps, faster asset loading, less runtime memory usage, etc. * **Per-Asset Loader Settings**: Individual assets cannot define their own loaders that override the defaults. Additionally, they cannot provide per-asset settings to their loaders. This is a huge limitation, as many asset types don't provide all information necessary for Bevy _inside_ the asset. For example, a raw PNG image says nothing about how it should be sampled (ex: linear vs nearest). * **Asset `.meta` files**: assets should have configuration files stored adjacent to the asset in question, which allows the user to configure asset-type-specific settings. These settings should be accessible during the pre-processing phase. Modifying a `.meta` file should trigger a re-processing / re-load of the asset. It should be possible to configure asset loaders from the meta file. * **Processed Asset Hot Reloading**: Changes to processed assets (or their dependencies) should result in re-processing them and re-loading the results in live Bevy Apps. * **Asset Dependency Tracking**: The current bevy_asset has no good way to wait for asset dependencies to load. It punts this as an exercise for consumers of the loader apis, which is unreasonable and error prone. There should be easy, ergonomic ways to wait for assets to load and block some logic on an asset's entire dependency tree loading. * **Runtime Asset Loading**: it should be (optionally) possible to load arbitrary assets dynamically at runtime. This necessitates being able to deploy and run the asset server alongside Bevy Apps on _all platforms_. For example, we should be able to invoke the shader compiler at runtime, stream scenes from sources like the internet, etc. To keep deployed binaries (and startup times) small, the runtime asset server configuration should be configurable with different settings compared to the "pre processor asset server". * **Multiple Backends**: It should be possible to load assets from arbitrary sources (filesystems, the internet, remote asset serves, etc). * **Asset Packing**: It should be possible to deploy assets in compressed "packs", which makes it easier and more efficient to distribute assets with Bevy Apps. * **Asset Handoff**: It should be possible to hold a "live" asset handle, which correlates to runtime data, without actually holding the asset in memory. Ex: it must be possible to hold a reference to a GPU mesh generated from a "mesh asset" without keeping the mesh data in CPU memory * **Per-Platform Processed Assets**: Different platforms and app distributions have different capabilities and requirements. Some platforms need lower asset resolutions or different asset formats to operate within the hardware constraints of the platform. It should be possible to define per-platform asset processing profiles. And it should be possible to deploy only the assets required for a given platform. These features have architectural implications that are significant enough to require a full rewrite. The current Bevy Asset implementation got us this far, but it can take us no farther. This PR defines a brand new asset system that implements most of these features, while laying the foundations for the remaining features to be built. ## Bevy Asset V2 Here is a quick overview of the features introduced in this PR. * **Asset Preprocessing**: Preprocess assets at development time into more efficient (and configurable) representations * **Dependency Aware**: Dependencies required to process an asset are tracked. If an asset's processed dependency changes, it will be reprocessed * **Hot Reprocessing/Reloading**: detect changes to asset source files, reprocess them if they have changed, and then hot-reload them in Bevy Apps. * **Only Process Changes**: Assets are only re-processed when their source file (or meta file) has changed. This uses hashing and timestamps to avoid processing assets that haven't changed. * **Transactional and Reliable**: Uses write-ahead logging (a technique commonly used by databases) to recover from crashes / forced-exits. Whenever possible it avoids full-reprocessing / only uncompleted transactions will be reprocessed. When the processor is running in parallel with a Bevy App, processor asset writes block Bevy App asset reads. Reading metadata + asset bytes is guaranteed to be transactional / correctly paired. * **Portable / Run anywhere / Database-free**: The processor does not rely on an in-memory database (although it uses some database techniques for reliability). This is important because pretty much all in-memory databases have unsupported platforms or build complications. * **Configure Processor Defaults Per File Type**: You can say "use this processor for all files of this type". * **Custom Processors**: The `Processor` trait is flexible and unopinionated. It can be implemented by downstream plugins. * **LoadAndSave Processors**: Most asset processing scenarios can be expressed as "run AssetLoader A, save the results using AssetSaver X, and then load the result using AssetLoader B". For example, load this png image using `PngImageLoader`, which produces an `Image` asset and then save it using `CompressedImageSaver` (which also produces an `Image` asset, but in a compressed format), which takes an `Image` asset as input. This means if you have an `AssetLoader` for an asset, you are already half way there! It also means that you can share AssetSavers across multiple loaders. Because `CompressedImageSaver` accepts Bevy's generic Image asset as input, it means you can also use it with some future `JpegImageLoader`. * **Loader and Saver Settings**: Asset Loaders and Savers can now define their own settings types, which are passed in as input when an asset is loaded / saved. Each asset can define its own settings. * **Asset `.meta` files**: configure asset loaders, their settings, enable/disable processing, and configure processor settings * **Runtime Asset Dependency Tracking** Runtime asset dependencies (ex: if an asset contains a `Handle<Image>`) are tracked by the asset server. An event is emitted when an asset and all of its dependencies have been loaded * **Unprocessed Asset Loading**: Assets do not require preprocessing. They can be loaded directly. A processed asset is just a "normal" asset with some extra metadata. Asset Loaders don't need to know or care about whether or not an asset was processed. * **Async Asset IO**: Asset readers/writers use async non-blocking interfaces. Note that because Rust doesn't yet support async traits, there is a bit of manual Boxing / Future boilerplate. This will hopefully be removed in the near future when Rust gets async traits. * **Pluggable Asset Readers and Writers**: Arbitrary asset source readers/writers are supported, both by the processor and the asset server. * **Better Asset Handles** * **Single Arc Tree**: Asset Handles now use a single arc tree that represents the lifetime of the asset. This makes their implementation simpler, more efficient, and allows us to cheaply attach metadata to handles. Ex: the AssetPath of a handle is now directly accessible on the handle itself! * **Const Typed Handles**: typed handles can be constructed in a const context. No more weird "const untyped converted to typed at runtime" patterns! * **Handles and Ids are Smaller / Faster To Hash / Compare**: Typed `Handle<T>` is now much smaller in memory and `AssetId<T>` is even smaller. * **Weak Handle Usage Reduction**: In general Handles are now considered to be "strong". Bevy features that previously used "weak `Handle<T>`" have been ported to `AssetId<T>`, which makes it statically clear that the features do not hold strong handles (while retaining strong type information). Currently Handle::Weak still exists, but it is very possible that we can remove that entirely. * **Efficient / Dense Asset Ids**: Assets now have efficient dense runtime asset ids, which means we can avoid expensive hash lookups. Assets are stored in Vecs instead of HashMaps. There are now typed and untyped ids, which means we no longer need to store dynamic type information in the ID for typed handles. "AssetPathId" (which was a nightmare from a performance and correctness standpoint) has been entirely removed in favor of dense ids (which are retrieved for a path on load) * **Direct Asset Loading, with Dependency Tracking**: Assets that are defined at runtime can still have their dependencies tracked by the Asset Server (ex: if you create a material at runtime, you can still wait for its textures to load). This is accomplished via the (currently optional) "asset dependency visitor" trait. This system can also be used to define a set of assets to load, then wait for those assets to load. * **Async folder loading**: Folder loading also uses this system and immediately returns a handle to the LoadedFolder asset, which means folder loading no longer blocks on directory traversals. * **Improved Loader Interface**: Loaders now have a specific "top level asset type", which makes returning the top-level asset simpler and statically typed. * **Basic Image Settings and Processing**: Image assets can now be processed into the gpu-friendly Basic Universal format. The ImageLoader now has a setting to define what format the image should be loaded as. Note that this is just a minimal MVP ... plenty of additional work to do here. To demo this, enable the `basis-universal` feature and turn on asset processing. * **Simpler Audio Play / AudioSink API**: Asset handle providers are cloneable, which means the Audio resource can mint its own handles. This means you can now do `let sink_handle = audio.play(music)` instead of `let sink_handle = audio_sinks.get_handle(audio.play(music))`. Note that this might still be replaced by https://github.com/bevyengine/bevy/pull/8424. **Removed Handle Casting From Engine Features**: Ex: FontAtlases no longer use casting between handle types ## Using The New Asset System ### Normal Unprocessed Asset Loading By default the `AssetPlugin` does not use processing. It behaves pretty much the same way as the old system. If you are defining a custom asset, first derive `Asset`: ```rust #[derive(Asset)] struct Thing { value: String, } ``` Initialize the asset: ```rust app.init_asset:<Thing>() ``` Implement a new `AssetLoader` for it: ```rust #[derive(Default)] struct ThingLoader; #[derive(Serialize, Deserialize, Default)] pub struct ThingSettings { some_setting: bool, } impl AssetLoader for ThingLoader { type Asset = Thing; type Settings = ThingSettings; fn load<'a>( &'a self, reader: &'a mut Reader, settings: &'a ThingSettings, load_context: &'a mut LoadContext, ) -> BoxedFuture<'a, Result<Thing, anyhow::Error>> { Box::pin(async move { let mut bytes = Vec::new(); reader.read_to_end(&mut bytes).await?; // convert bytes to value somehow Ok(Thing { value }) }) } fn extensions(&self) -> &[&str] { &["thing"] } } ``` Note that this interface will get much cleaner once Rust gets support for async traits. `Reader` is an async futures_io::AsyncRead. You can stream bytes as they come in or read them all into a `Vec<u8>`, depending on the context. You can use `let handle = load_context.load(path)` to kick off a dependency load, retrieve a handle, and register the dependency for the asset. Then just register the loader in your Bevy app: ```rust app.init_asset_loader::<ThingLoader>() ``` Now just add your `Thing` asset files into the `assets` folder and load them like this: ```rust fn system(asset_server: Res<AssetServer>) { let handle = Handle<Thing> = asset_server.load("cool.thing"); } ``` You can check load states directly via the asset server: ```rust if asset_server.load_state(&handle) == LoadState::Loaded { } ``` You can also listen for events: ```rust fn system(mut events: EventReader<AssetEvent<Thing>>, handle: Res<SomeThingHandle>) { for event in events.iter() { if event.is_loaded_with_dependencies(&handle) { } } } ``` Note the new `AssetEvent::LoadedWithDependencies`, which only fires when the asset is loaded _and_ all dependencies (and their dependencies) have loaded. Unlike the old asset system, for a given asset path all `Handle<T>` values point to the same underlying Arc. This means Handles can cheaply hold more asset information, such as the AssetPath: ```rust // prints the AssetPath of the handle info!("{:?}", handle.path()) ``` ### Processed Assets Asset processing can be enabled via the `AssetPlugin`. When developing Bevy Apps with processed assets, do this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev())) ``` This runs the `AssetProcessor` in the background with hot-reloading. It reads assets from the `assets` folder, processes them, and writes them to the `.imported_assets` folder. Asset loads in the Bevy App will wait for a processed version of the asset to become available. If an asset in the `assets` folder changes, it will be reprocessed and hot-reloaded in the Bevy App. When deploying processed Bevy apps, do this: ```rust app.add_plugins(DefaultPlugins.set(AssetPlugin::processed())) ``` This does not run the `AssetProcessor` in the background. It behaves like `AssetPlugin::unprocessed()`, but reads assets from `.imported_assets`. When the `AssetProcessor` is running, it will populate sibling `.meta` files for assets in the `assets` folder. Meta files for assets that do not have a processor configured look like this: ```rust ( meta_format_version: "1.0", asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: FromExtension, ), ), ) ``` This is metadata for an image asset. For example, if you have `assets/my_sprite.png`, this could be the metadata stored at `assets/my_sprite.png.meta`. Meta files are totally optional. If no metadata exists, the default settings will be used. In short, this file says "load this asset with the ImageLoader and use the file extension to determine the image type". This type of meta file is supported in all AssetPlugin modes. If in `Unprocessed` mode, the asset (with the meta settings) will be loaded directly. If in `ProcessedDev` mode, the asset file will be copied directly to the `.imported_assets` folder. The meta will also be copied directly to the `.imported_assets` folder, but with one addition: ```rust ( meta_format_version: "1.0", processed_info: Some(( hash: 12415480888597742505, full_hash: 14344495437905856884, process_dependencies: [], )), asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: FromExtension, ), ), ) ``` `processed_info` contains `hash` (a direct hash of the asset and meta bytes), `full_hash` (a hash of `hash` and the hashes of all `process_dependencies`), and `process_dependencies` (the `path` and `full_hash` of every process_dependency). A "process dependency" is an asset dependency that is _directly_ used when processing the asset. Images do not have process dependencies, so this is empty. When the processor is enabled, you can use the `Process` metadata config: ```rust ( meta_format_version: "1.0", asset: Process( processor: "bevy_asset::processor::process::LoadAndSave<bevy_render::texture::image_loader::ImageLoader, bevy_render::texture::compressed_image_saver::CompressedImageSaver>", settings: ( loader_settings: ( format: FromExtension, ), saver_settings: ( generate_mipmaps: true, ), ), ), ) ``` This configures the asset to use the `LoadAndSave` processor, which runs an AssetLoader and feeds the result into an AssetSaver (which saves the given Asset and defines a loader to load it with). (for terseness LoadAndSave will likely get a shorter/friendlier type name when [Stable Type Paths](#7184) lands). `LoadAndSave` is likely to be the most common processor type, but arbitrary processors are supported. `CompressedImageSaver` saves an `Image` in the Basis Universal format and configures the ImageLoader to load it as basis universal. The `AssetProcessor` will read this meta, run it through the LoadAndSave processor, and write the basis-universal version of the image to `.imported_assets`. The final metadata will look like this: ```rust ( meta_format_version: "1.0", processed_info: Some(( hash: 905599590923828066, full_hash: 9948823010183819117, process_dependencies: [], )), asset: Load( loader: "bevy_render::texture::image_loader::ImageLoader", settings: ( format: Format(Basis), ), ), ) ``` To try basis-universal processing out in Bevy examples, (for example `sprite.rs`), change `add_plugins(DefaultPlugins)` to `add_plugins(DefaultPlugins.set(AssetPlugin::processed_dev()))` and run with the `basis-universal` feature enabled: `cargo run --features=basis-universal --example sprite`. To create a custom processor, there are two main paths: 1. Use the `LoadAndSave` processor with an existing `AssetLoader`. Implement the `AssetSaver` trait, register the processor using `asset_processor.register_processor::<LoadAndSave<ImageLoader, CompressedImageSaver>>(image_saver.into())`. 2. Implement the `Process` trait directly and register it using: `asset_processor.register_processor(thing_processor)`. You can configure default processors for file extensions like this: ```rust asset_processor.set_default_processor::<ThingProcessor>("thing") ``` There is one more metadata type to be aware of: ```rust ( meta_format_version: "1.0", asset: Ignore, ) ``` This will ignore the asset during processing / prevent it from being written to `.imported_assets`. The AssetProcessor stores a transaction log at `.imported_assets/log` and uses it to gracefully recover from unexpected stops. This means you can force-quit the processor (and Bevy Apps running the processor in parallel) at arbitrary times! `.imported_assets` is "local state". It should _not_ be checked into source control. It should also be considered "read only". In practice, you _can_ modify processed assets and processed metadata if you really need to test something. But those modifications will not be represented in the hashes of the assets, so the processed state will be "out of sync" with the source assets. The processor _will not_ fix this for you. Either revert the change after you have tested it, or delete the processed files so they can be re-populated. ## Open Questions There are a number of open questions to be discussed. We should decide if they need to be addressed in this PR and if so, how we will address them: ### Implied Dependencies vs Dependency Enumeration There are currently two ways to populate asset dependencies: * **Implied via AssetLoaders**: if an AssetLoader loads an asset (and retrieves a handle), a dependency is added to the list. * **Explicit via the optional Asset::visit_dependencies**: if `server.load_asset(my_asset)` is called, it will call `my_asset.visit_dependencies`, which will grab dependencies that have been manually defined for the asset via the Asset trait impl (which can be derived). This means that defining explicit dependencies is optional for "loaded assets". And the list of dependencies is always accurate because loaders can only produce Handles if they register dependencies. If an asset was loaded with an AssetLoader, it only uses the implied dependencies. If an asset was created at runtime and added with `asset_server.load_asset(MyAsset)`, it will use `Asset::visit_dependencies`. However this can create a behavior mismatch between loaded assets and equivalent "created at runtime" assets if `Assets::visit_dependencies` doesn't exactly match the dependencies produced by the AssetLoader. This behavior mismatch can be resolved by completely removing "implied loader dependencies" and requiring `Asset::visit_dependencies` to supply dependency data. But this creates two problems: * It makes defining loaded assets harder and more error prone: Devs must remember to manually annotate asset dependencies with `#[dependency]` when deriving `Asset`. For more complicated assets (such as scenes), the derive likely wouldn't be sufficient and a manual `visit_dependencies` impl would be required. * Removes the ability to immediately kick off dependency loads: When AssetLoaders retrieve a Handle, they also immediately kick off an asset load for the handle, which means it can start loading in parallel _before_ the asset finishes loading. For large assets, this could be significant. (although this could be mitigated for processed assets if we store dependencies in the processed meta file and load them ahead of time) ### Eager ProcessorDev Asset Loading I made a controversial call in the interest of fast startup times ("time to first pixel") for the "processor dev mode configuration". When initializing the AssetProcessor, current processed versions of unchanged assets are yielded immediately, even if their dependencies haven't been checked yet for reprocessing. This means that non-current-state-of-filesystem-but-previously-valid assets might be returned to the App first, then hot-reloaded if/when their dependencies change and the asset is reprocessed. Is this behavior desirable? There is largely one alternative: do not yield an asset from the processor to the app until all of its dependencies have been checked for changes. In some common cases (load dependency has not changed since last run) this will increase startup time. The main question is "by how much" and is that slower startup time worth it in the interest of only yielding assets that are true to the current state of the filesystem. Should this be configurable? I'm starting to think we should only yield an asset after its (historical) dependencies have been checked for changes + processed as necessary, but I'm curious what you all think. ### Paths Are Currently The Only Canonical ID / Do We Want Asset UUIDs? In this implementation AssetPaths are the only canonical asset identifier (just like the previous Bevy Asset system and Godot). Moving assets will result in re-scans (and currently reprocessing, although reprocessing can easily be avoided with some changes). Asset renames/moves will break code and assets that rely on specific paths, unless those paths are fixed up. Do we want / need "stable asset uuids"? Introducing them is very possible: 1. Generate a UUID and include it in .meta files 2. Support UUID in AssetPath 3. Generate "asset indices" which are loaded on startup and map UUIDs to paths. 4 (maybe). Consider only supporting UUIDs for processed assets so we can generate quick-to-load indices instead of scanning meta files. The main "pro" is that assets referencing UUIDs don't need to be migrated when a path changes. The main "con" is that UUIDs cannot be "lazily resolved" like paths. They need a full view of all assets to answer the question "does this UUID exist". Which means UUIDs require the AssetProcessor to fully finish startup scans before saying an asset doesnt exist. And they essentially require asset pre-processing to use in apps, because scanning all asset metadata files at runtime to resolve a UUID is not viable for medium-to-large apps. It really requires a pre-generated UUID index, which must be loaded before querying for assets. I personally think this should be investigated in a separate PR. Paths aren't going anywhere ... _everyone_ uses filesystems (and filesystem-like apis) to manage their asset source files. I consider them permanent canonical asset information. Additionally, they behave well for both processed and unprocessed asset modes. Given that Bevy is supporting both, this feels like the right canonical ID to start with. UUIDS (and maybe even other indexed-identifier types) can be added later as necessary. ### Folder / File Naming Conventions All asset processing config currently lives in the `.imported_assets` folder. The processor transaction log is in `.imported_assets/log`. Processed assets are added to `.imported_assets/Default`, which will make migrating to processed asset profiles (ex: a `.imported_assets/Mobile` profile) a non-breaking change. It also allows us to create top-level files like `.imported_assets/log` without it being interpreted as an asset. Meta files currently have a `.meta` suffix. Do we like these names and conventions? ### Should the `AssetPlugin::processed_dev` configuration enable `watch_for_changes` automatically? Currently it does (which I think makes sense), but it does make it the only configuration that enables watch_for_changes by default. ### Discuss on_loaded High Level Interface: This PR includes a very rough "proof of concept" `on_loaded` system adapter that uses the `LoadedWithDependencies` event in combination with `asset_server.load_asset` dependency tracking to support this pattern ```rust fn main() { App::new() .init_asset::<MyAssets>() .add_systems(Update, on_loaded(create_array_texture)) .run(); } #[derive(Asset, Clone)] struct MyAssets { #[dependency] picture_of_my_cat: Handle<Image>, #[dependency] picture_of_my_other_cat: Handle<Image>, } impl FromWorld for ArrayTexture { fn from_world(world: &mut World) -> Self { picture_of_my_cat: server.load("meow.png"), picture_of_my_other_cat: server.load("meeeeeeeow.png"), } } fn spawn_cat(In(my_assets): In<MyAssets>, mut commands: Commands) { commands.spawn(SpriteBundle { texture: my_assets.picture_of_my_cat.clone(), ..default() }); commands.spawn(SpriteBundle { texture: my_assets.picture_of_my_other_cat.clone(), ..default() }); } ``` The implementation is _very_ rough. And it is currently unsafe because `bevy_ecs` doesn't expose some internals to do this safely from inside `bevy_asset`. There are plenty of unanswered questions like: * "do we add a Loadable" derive? (effectively automate the FromWorld implementation above) * Should `MyAssets` even be an Asset? (largely implemented this way because it elegantly builds on `server.load_asset(MyAsset { .. })` dependency tracking). We should think hard about what our ideal API looks like (and if this is a pattern we want to support). Not necessarily something we need to solve in this PR. The current `on_loaded` impl should probably be removed from this PR before merging. ## Clarifying Questions ### What about Assets as Entities? This Bevy Asset V2 proposal implementation initially stored Assets as ECS Entities. Instead of `AssetId<T>` + the `Assets<T>` resource it used `Entity` as the asset id and Asset values were just ECS components. There are plenty of compelling reasons to do this: 1. Easier to inline assets in Bevy Scenes (as they are "just" normal entities + components) 2. More flexible queries: use the power of the ECS to filter assets (ex: `Query<Mesh, With<Tree>>`). 3. Extensible. Users can add arbitrary component data to assets. 4. Things like "component visualization tools" work out of the box to visualize asset data. However Assets as Entities has a ton of caveats right now: * We need to be able to allocate entity ids without a direct World reference (aka rework id allocator in Entities ... i worked around this in my prototypes by just pre allocating big chunks of entities) * We want asset change events in addition to ECS change tracking ... how do we populate them when mutations can come from anywhere? Do we use Changed queries? This would require iterating over the change data for all assets every frame. Is this acceptable or should we implement a new "event based" component change detection option? * Reconciling manually created assets with asset-system managed assets has some nuance (ex: are they "loaded" / do they also have that component metadata?) * "how do we handle "static" / default entity handles" (ties in to the Entity Indices discussion: https://github.com/bevyengine/bevy/discussions/8319). This is necessary for things like "built in" assets and default handles in things like SpriteBundle. * Storing asset information as a component makes it easy to "invalidate" asset state by removing the component (or forcing modifications). Ideally we have ways to lock this down (some combination of Rust type privacy and ECS validation) In practice, how we store and identify assets is a reasonably superficial change (porting off of Assets as Entities and implementing dedicated storage + ids took less than a day). So once we sort out the remaining challenges the flip should be straightforward. Additionally, I do still have "Assets as Entities" in my commit history, so we can reuse that work. I personally think "assets as entities" is a good endgame, but it also doesn't provide _significant_ value at the moment and it certainly isn't ready yet with the current state of things. ### Why not Distill? [Distill](https://github.com/amethyst/distill) is a high quality fully featured asset system built in Rust. It is very natural to ask "why not just use Distill?". It is also worth calling out that for awhile, [we planned on adopting Distill / I signed off on it](https://github.com/bevyengine/bevy/issues/708). However I think Bevy has a number of constraints that make Distill adoption suboptimal: * **Architectural Simplicity:** * Distill's processor requires an in-memory database (lmdb) and RPC networked API (using Cap'n Proto). Each of these introduces API complexity that increases maintenance burden and "code grokability". Ignoring tests, documentation, and examples, Distill has 24,237 lines of Rust code (including generated code for RPC + database interactions). If you ignore generated code, it has 11,499 lines. * Bevy builds the AssetProcessor and AssetServer using pluggable AssetReader/AssetWriter Rust traits with simple io interfaces. They do not necessitate databases or RPC interfaces (although Readers/Writers could use them if that is desired). Bevy Asset V2 (at the time of writing this PR) is 5,384 lines of Rust code (ignoring tests, documentation, and examples). Grain of salt: Distill does have more features currently (ex: Asset Packing, GUIDS, remote-out-of-process asset processor). I do plan to implement these features in Bevy Asset V2 and I personally highly doubt they will meaningfully close the 6115 lines-of-code gap. * This complexity gap (which while illustrated by lines of code, is much bigger than just that) is noteworthy to me. Bevy should be hackable and there are pillars of Distill that are very hard to understand and extend. This is a matter of opinion (and Bevy Asset V2 also has complicated areas), but I think Bevy Asset V2 is much more approachable for the average developer. * Necessary disclaimer: counting lines of code is an extremely rough complexity metric. Read the code and form your own opinions. * **Optional Asset Processing:** Not all Bevy Apps (or Bevy App developers) need / want asset preprocessing. Processing increases the complexity of the development environment by introducing things like meta files, imported asset storage, running processors in the background, waiting for processing to finish, etc. Distill _requires_ preprocessing to work. With Bevy Asset V2 processing is fully opt-in. The AssetServer isn't directly aware of asset processors at all. AssetLoaders only care about converting bytes to runtime Assets ... they don't know or care if the bytes were pre-processed or not. Processing is "elegantly" (forgive my self-congratulatory phrasing) layered on top and builds on the existing Asset system primitives. * **Direct Filesystem Access to Processed Asset State:** Distill stores processed assets in a database. This makes debugging / inspecting the processed outputs harder (either requires special tooling to query the database or they need to be "deployed" to be inspected). Bevy Asset V2, on the other hand, stores processed assets in the filesystem (by default ... this is configurable). This makes interacting with the processed state more natural. Note that both Godot and Unity's new asset system store processed assets in the filesystem. * **Portability**: Because Distill's processor uses lmdb and RPC networking, it cannot be run on certain platforms (ex: lmdb is a non-rust dependency that cannot run on the web, some platforms don't support running network servers). Bevy should be able to process assets everywhere (ex: run the Bevy Editor on the web, compile + process shaders on mobile, etc). Distill does partially mitigate this problem by supporting "streaming" assets via the RPC protocol, but this is not a full solve from my perspective. And Bevy Asset V2 can (in theory) also stream assets (without requiring RPC, although this isn't implemented yet) Note that I _do_ still think Distill would be a solid asset system for Bevy. But I think the approach in this PR is a better solve for Bevy's specific "asset system requirements". ### Doesn't async-fs just shim requests to "sync" `std::fs`? What is the point? "True async file io" has limited / spotty platform support. async-fs (and the rust async ecosystem generally ... ex Tokio) currently use async wrappers over std::fs that offload blocking requests to separate threads. This may feel unsatisfying, but it _does_ still provide value because it prevents our task pools from blocking on file system operations (which would prevent progress when there are many tasks to do, but all threads in a pool are currently blocking on file system ops). Additionally, using async APIs for our AssetReaders and AssetWriters also provides value because we can later add support for "true async file io" for platforms that support it. _And_ we can implement other "true async io" asset backends (such as networked asset io). ## Draft TODO - [x] Fill in missing filesystem event APIs: file removed event (which is expressed as dangling RenameFrom events in some cases), file/folder renamed event - [x] Assets without loaders are not moved to the processed folder. This breaks things like referenced `.bin` files for GLTFs. This should be configurable per-non-asset-type. - [x] Initial implementation of Reflect and FromReflect for Handle. The "deserialization" parity bar is low here as this only worked with static UUIDs in the old impl ... this is a non-trivial problem. Either we add a Handle::AssetPath variant that gets "upgraded" to a strong handle on scene load or we use a separate AssetRef type for Bevy scenes (which is converted to a runtime Handle on load). This deserves its own discussion in a different pr. - [x] Populate read_asset_bytes hash when run by the processor (a bit of a special case .. when run by the processor the processed meta will contain the hash so we don't need to compute it on the spot, but we don't want/need to read the meta when run by the main AssetServer) - [x] Delay hot reloading: currently filesystem events are handled immediately, which creates timing issues in some cases. For example hot reloading images can sometimes break because the image isn't finished writing. We should add a delay, likely similar to the [implementation in this PR](https://github.com/bevyengine/bevy/pull/8503). - [x] Port old platform-specific AssetIo implementations to the new AssetReader interface (currently missing Android and web) - [x] Resolve on_loaded unsafety (either by removing the API entirely or removing the unsafe) - [x] Runtime loader setting overrides - [x] Remove remaining unwraps that should be error-handled. There are number of TODOs here - [x] Pretty AssetPath Display impl - [x] Document more APIs - [x] Resolve spurious "reloading because it has changed" events (to repro run load_gltf with `processed_dev()`) - [x] load_dependency hot reloading currently only works for processed assets. If processing is disabled, load_dependency changes are not hot reloaded. - [x] Replace AssetInfo dependency load/fail counters with `loading_dependencies: HashSet<UntypedAssetId>` to prevent reloads from (potentially) breaking counters. Storing this will also enable "dependency reloaded" events (see [Next Steps](#next-steps)) - [x] Re-add filesystem watcher cargo feature gate (currently it is not optional) - [ ] Migration Guide - [ ] Changelog ## Followup TODO - [ ] Replace "eager unchanged processed asset loading" behavior with "don't returned unchanged processed asset until dependencies have been checked". - [ ] Add true `Ignore` AssetAction that does not copy the asset to the imported_assets folder. - [ ] Finish "live asset unloading" (ex: free up CPU asset memory after uploading an image to the GPU), rethink RenderAssets, and port renderer features. The `Assets` collection uses `Option<T>` for asset storage to support its removal. (1) the Option might not actually be necessary ... might be able to just remove from the collection entirely (2) need to finalize removal apis - [ ] Try replacing the "channel based" asset id recycling with something a bit more efficient (ex: we might be able to use raw atomic ints with some cleverness) - [ ] Consider adding UUIDs to processed assets (scoped just to helping identify moved assets ... not exposed to load queries ... see [Next Steps](#next-steps)) - [ ] Store "last modified" source asset and meta timestamps in processed meta files to enable skipping expensive hashing when the file wasn't changed - [ ] Fix "slow loop" handle drop fix - [ ] Migrate to TypeName - [x] Handle "loader preregistration". See #9429 ## Next Steps * **Configurable per-type defaults for AssetMeta**: It should be possible to add configuration like "all png image meta should default to using nearest sampling" (currently this hard-coded per-loader/processor Settings::default() impls). Also see the "Folder Meta" bullet point. * **Avoid Reprocessing on Asset Renames / Moves**: See the "canonical asset ids" discussion in [Open Questions](#open-questions) and the relevant bullet point in [Draft TODO](#draft-todo). Even without canonical ids, folder renames could avoid reprocessing in some cases. * **Multiple Asset Sources**: Expand AssetPath to support "asset source names" and support multiple AssetReaders in the asset server (ex: `webserver://some_path/image.png` backed by an Http webserver AssetReader). The "default" asset reader would use normal `some_path/image.png` paths. Ideally this works in combination with multiple AssetWatchers for hot-reloading * **Stable Type Names**: this pr removes the TypeUuid requirement from assets in favor of `std::any::type_name`. This makes defining assets easier (no need to generate a new uuid / use weird proc macro syntax). It also makes reading meta files easier (because things have "friendly names"). We also use type names for components in scene files. If they are good enough for components, they are good enough for assets. And consistency across Bevy pillars is desirable. However, `std::any::type_name` is not guaranteed to be stable (although in practice it is). We've developed a [stable type path](https://github.com/bevyengine/bevy/pull/7184) to resolve this, which should be adopted when it is ready. * **Command Line Interface**: It should be possible to run the asset processor in a separate process from the command line. This will also require building a network-server-backed AssetReader to communicate between the app and the processor. We've been planning to build a "bevy cli" for awhile. This seems like a good excuse to build it. * **Asset Packing**: This is largely an additive feature, so it made sense to me to punt this until we've laid the foundations in this PR. * **Per-Platform Processed Assets**: It should be possible to generate assets for multiple platforms by supporting multiple "processor profiles" per asset (ex: compress with format X on PC and Y on iOS). I think there should probably be arbitrary "profiles" (which can be separate from actual platforms), which are then assigned to a given platform when generating the final asset distribution for that platform. Ex: maybe devs want a "Mobile" profile that is shared between iOS and Android. Or a "LowEnd" profile shared between web and mobile. * **Versioning and Migrations**: Assets, Loaders, Savers, and Processors need to have versions to determine if their schema is valid. If an asset / loader version is incompatible with the current version expected at runtime, the processor should be able to migrate them. I think we should try using Bevy Reflect for this, as it would allow us to load the old version as a dynamic Reflect type without actually having the old Rust type. It would also allow us to define "patches" to migrate between versions (Bevy Reflect devs are currently working on patching). The `.meta` file already has its own format version. Migrating that to new versions should also be possible. * **Real Copy-on-write AssetPaths**: Rust's actual Cow (clone-on-write type) currently used by AssetPath can still result in String clones that aren't actually necessary (cloning an Owned Cow clones the contents). Bevy's asset system requires cloning AssetPaths in a number of places, which result in actual clones of the internal Strings. This is not efficient. AssetPath internals should be reworked to exhibit truer cow-like-behavior that reduces String clones to the absolute minimum. * **Consider processor-less processing**: In theory the AssetServer could run processors "inline" even if the background AssetProcessor is disabled. If we decide this is actually desirable, we could add this. But I don't think its a priority in the short or medium term. * **Pre-emptive dependency loading**: We could encode dependencies in processed meta files, which could then be used by the Asset Server to kick of dependency loads as early as possible (prior to starting the actual asset load). Is this desirable? How much time would this save in practice? * **Optimize Processor With UntypedAssetIds**: The processor exclusively uses AssetPath to identify assets currently. It might be possible to swap these out for UntypedAssetIds in some places, which are smaller / cheaper to hash and compare. * **One to Many Asset Processing**: An asset source file that produces many assets currently must be processed into a single "processed" asset source. If labeled assets can be written separately they can each have their own configured savers _and_ they could be loaded more granularly. Definitely worth exploring! * **Automatically Track "Runtime-only" Asset Dependencies**: Right now, tracking "created at runtime" asset dependencies requires adding them via `asset_server.load_asset(StandardMaterial::default())`. I think with some cleverness we could also do this for `materials.add(StandardMaterial::default())`, making tracking work "everywhere". There are challenges here relating to change detection / ensuring the server is made aware of dependency changes. This could be expensive in some cases. * **"Dependency Changed" events**: Some assets have runtime artifacts that need to be re-generated when one of their dependencies change (ex: regenerate a material's bind group when a Texture needs to change). We are generating the dependency graph so we can definitely produce these events. Buuuuut generating these events will have a cost / they could be high frequency for some assets, so we might want this to be opt-in for specific cases. * **Investigate Storing More Information In Handles**: Handles can now store arbitrary information, which makes it cheaper and easier to access. How much should we move into them? Canonical asset load states (via atomics)? (`handle.is_loaded()` would be very cool). Should we store the entire asset and remove the `Assets<T>` collection? (`Arc<RwLock<Option<Image>>>`?) * **Support processing and loading files without extensions**: This is a pretty arbitrary restriction and could be supported with very minimal changes. * **Folder Meta**: It would be nice if we could define per folder processor configuration defaults (likely in a `.meta` or `.folder_meta` file). Things like "default to linear filtering for all Images in this folder". * **Replace async_broadcast with event-listener?** This might be approximately drop-in for some uses and it feels more light weight * **Support Running the AssetProcessor on the Web**: Most of the hard work is done here, but there are some easy straggling TODOs (make the transaction log an interface instead of a direct file writer so we can write a web storage backend, implement an AssetReader/AssetWriter that reads/writes to something like LocalStorage). * **Consider identifying and preventing circular dependencies**: This is especially important for "processor dependencies", as processing will silently never finish in these cases. * **Built-in/Inlined Asset Hot Reloading**: This PR regresses "built-in/inlined" asset hot reloading (previously provided by the DebugAssetServer). I'm intentionally punting this because I think it can be cleanly implemented with "multiple asset sources" by registering a "debug asset source" (ex: `debug://bevy_pbr/src/render/pbr.wgsl` asset paths) in combination with an AssetWatcher for that asset source and support for "manually loading pats with asset bytes instead of AssetReaders". The old DebugAssetServer was quite nasty and I'd love to avoid that hackery going forward. * **Investigate ways to remove double-parsing meta files**: Parsing meta files currently involves parsing once with "minimal" versions of the meta file to extract the type name of the loader/processor config, then parsing again to parse the "full" meta. This is suboptimal. We should be able to define custom deserializers that (1) assume the loader/processor type name comes first (2) dynamically looks up the loader/processor registrations to deserialize settings in-line (similar to components in the bevy scene format). Another alternative: deserialize as dynamic Reflect objects and then convert. * **More runtime loading configuration**: Support using the Handle type as a hint to select an asset loader (instead of relying on AssetPath extensions) * **More high level Processor trait implementations**: For example, it might be worth adding support for arbitrary chains of "asset transforms" that modify an in-memory asset representation between loading and saving. (ex: load a Mesh, run a `subdivide_mesh` transform, followed by a `flip_normals` transform, then save the mesh to an efficient compressed format). * **Bevy Scene Handle Deserialization**: (see the relevant [Draft TODO item](#draft-todo) for context) * **Explore High Level Load Interfaces**: See [this discussion](#discuss-on_loaded-high-level-interface) for one prototype. * **Asset Streaming**: It would be great if we could stream Assets (ex: stream a long video file piece by piece) * **ID Exchanging**: In this PR Asset Handles/AssetIds are bigger than they need to be because they have a Uuid enum variant. If we implement an "id exchanging" system that trades Uuids for "efficient runtime ids", we can cut down on the size of AssetIds, making them more efficient. This has some open design questions, such as how to spawn entities with "default" handle values (as these wouldn't have access to the exchange api in the current system). * **Asset Path Fixup Tooling**: Assets that inline asset paths inside them will break when an asset moves. The asset system provides the functionality to detect when paths break. We should build a framework that enables formats to define "path migrations". This is especially important for scene files. For editor-generated files, we should also consider using UUIDs (see other bullet point) to avoid the need to migrate in these cases. --------- Co-authored-by: BeastLe9enD <beastle9end@outlook.de> Co-authored-by: Mike <mike.hsu@gmail.com> Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com>
2023-09-07 02:07:27 +00:00
[package.metadata.example.asset_processing]
name = "Asset Processing"
description = "Demonstrates how to process and load custom assets"
category = "Assets"
wasm = false
# Async Tasks
[[example]]
name = "async_compute"
path = "examples/async_tasks/async_compute.rs"
doc-scrape-examples = true
[package.metadata.example.async_compute]
name = "Async Compute"
description = "How to use `AsyncComputeTaskPool` to complete longer running tasks"
category = "Async Tasks"
wasm = false
[[example]]
name = "external_source_external_thread"
path = "examples/async_tasks/external_source_external_thread.rs"
doc-scrape-examples = true
[package.metadata.example.external_source_external_thread]
name = "External Source of Data on an External Thread"
description = "How to use an external thread to run an infinite task and communicate with a channel"
category = "Async Tasks"
wasm = false
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
# Audio
[[example]]
name = "audio"
path = "examples/audio/audio.rs"
doc-scrape-examples = true
[package.metadata.example.audio]
name = "Audio"
description = "Shows how to load and play an audio file"
category = "Audio"
wasm = true
[[example]]
name = "audio_control"
path = "examples/audio/audio_control.rs"
doc-scrape-examples = true
[package.metadata.example.audio_control]
name = "Audio Control"
description = "Shows how to load and play an audio file, and control how it's played"
category = "Audio"
wasm = true
[[example]]
name = "decodable"
path = "examples/audio/decodable.rs"
doc-scrape-examples = true
[package.metadata.example.decodable]
name = "Decodable"
description = "Shows how to create and register a custom audio source by implementing the `Decodable` type."
category = "Audio"
wasm = true
[[example]]
name = "spatial_audio_2d"
path = "examples/audio/spatial_audio_2d.rs"
doc-scrape-examples = true
[package.metadata.example.spatial_audio_2d]
name = "Spatial Audio 2D"
description = "Shows how to play spatial audio, and moving the emitter in 2D"
category = "Audio"
wasm = true
[[example]]
name = "spatial_audio_3d"
path = "examples/audio/spatial_audio_3d.rs"
doc-scrape-examples = true
[package.metadata.example.spatial_audio_3d]
name = "Spatial Audio 3D"
description = "Shows how to play spatial audio, and moving the emitter in 3D"
category = "Audio"
wasm = true
[[example]]
name = "pitch"
path = "examples/audio/pitch.rs"
[package.metadata.example.pitch]
name = "Pitch"
description = "Shows how to directly play a simple pitch"
category = "Audio"
wasm = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
# Diagnostics
[[example]]
name = "log_diagnostics"
path = "examples/diagnostics/log_diagnostics.rs"
doc-scrape-examples = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[package.metadata.example.log_diagnostics]
name = "Log Diagnostics"
description = "Add a plugin that logs diagnostics, like frames per second (FPS), to the console"
category = "Diagnostics"
wasm = true
2020-05-04 21:14:49 +00:00
[[example]]
name = "custom_diagnostic"
path = "examples/diagnostics/custom_diagnostic.rs"
doc-scrape-examples = true
2020-05-04 21:14:49 +00:00
[package.metadata.example.custom_diagnostic]
name = "Custom Diagnostic"
description = "Shows how to create a custom diagnostic"
category = "Diagnostics"
wasm = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
# ECS (Entity Component System)
2020-05-04 21:14:49 +00:00
[[example]]
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
name = "ecs_guide"
path = "examples/ecs/ecs_guide.rs"
doc-scrape-examples = true
2020-05-04 21:14:49 +00:00
[package.metadata.example.ecs_guide]
name = "ECS Guide"
description = "Full guide to Bevy's ECS"
category = "ECS (Entity Component System)"
wasm = false
[[example]]
name = "apply_deferred"
path = "examples/ecs/apply_deferred.rs"
doc-scrape-examples = true
[package.metadata.example.apply_deferred]
name = "Apply System Buffers"
description = "Show how to use `apply_deferred` system"
category = "ECS (Entity Component System)"
wasm = false
[[example]]
name = "component_change_detection"
path = "examples/ecs/component_change_detection.rs"
doc-scrape-examples = true
[package.metadata.example.component_change_detection]
name = "Component Change Detection"
description = "Change detection on components"
category = "ECS (Entity Component System)"
wasm = false
Implement `WorldQuery` derive macro (#2713) # Objective - Closes #786 - Closes #2252 - Closes #2588 This PR implements a derive macro that allows users to define their queries as structs with named fields. ## Example ```rust #[derive(WorldQuery)] #[world_query(derive(Debug))] struct NumQuery<'w, T: Component, P: Component> { entity: Entity, u: UNumQuery<'w>, generic: GenericQuery<'w, T, P>, } #[derive(WorldQuery)] #[world_query(derive(Debug))] struct UNumQuery<'w> { u_16: &'w u16, u_32_opt: Option<&'w u32>, } #[derive(WorldQuery)] #[world_query(derive(Debug))] struct GenericQuery<'w, T: Component, P: Component> { generic: (&'w T, &'w P), } #[derive(WorldQuery)] #[world_query(filter)] struct NumQueryFilter<T: Component, P: Component> { _u_16: With<u16>, _u_32: With<u32>, _or: Or<(With<i16>, Changed<u16>, Added<u32>)>, _generic_tuple: (With<T>, With<P>), _without: Without<Option<u16>>, _tp: PhantomData<(T, P)>, } fn print_nums_readonly(query: Query<NumQuery<u64, i64>, NumQueryFilter<u64, i64>>) { for num in query.iter() { println!("{:#?}", num); } } #[derive(WorldQuery)] #[world_query(mutable, derive(Debug))] struct MutNumQuery<'w, T: Component, P: Component> { i_16: &'w mut i16, i_32_opt: Option<&'w mut i32>, } fn print_nums(mut query: Query<MutNumQuery, NumQueryFilter<u64, i64>>) { for num in query.iter_mut() { println!("{:#?}", num); } } ``` ## TODOs: - [x] Add support for `&T` and `&mut T` - [x] Test - [x] Add support for optional types - [x] Test - [x] Add support for `Entity` - [x] Test - [x] Add support for nested `WorldQuery` - [x] Test - [x] Add support for tuples - [x] Test - [x] Add support for generics - [x] Test - [x] Add support for query filters - [x] Test - [x] Add support for `PhantomData` - [x] Test - [x] Refactor `read_world_query_field_type_info` - [x] Properly document `readonly` attribute for nested queries and the static assertions that guarantee safety - [x] Test that we never implement `ReadOnlyFetch` for types that need mutable access - [x] Test that we insert static assertions for nested `WorldQuery` that a user marked as readonly
2022-02-24 00:19:49 +00:00
[[example]]
name = "custom_query_param"
path = "examples/ecs/custom_query_param.rs"
doc-scrape-examples = true
Implement `WorldQuery` derive macro (#2713) # Objective - Closes #786 - Closes #2252 - Closes #2588 This PR implements a derive macro that allows users to define their queries as structs with named fields. ## Example ```rust #[derive(WorldQuery)] #[world_query(derive(Debug))] struct NumQuery<'w, T: Component, P: Component> { entity: Entity, u: UNumQuery<'w>, generic: GenericQuery<'w, T, P>, } #[derive(WorldQuery)] #[world_query(derive(Debug))] struct UNumQuery<'w> { u_16: &'w u16, u_32_opt: Option<&'w u32>, } #[derive(WorldQuery)] #[world_query(derive(Debug))] struct GenericQuery<'w, T: Component, P: Component> { generic: (&'w T, &'w P), } #[derive(WorldQuery)] #[world_query(filter)] struct NumQueryFilter<T: Component, P: Component> { _u_16: With<u16>, _u_32: With<u32>, _or: Or<(With<i16>, Changed<u16>, Added<u32>)>, _generic_tuple: (With<T>, With<P>), _without: Without<Option<u16>>, _tp: PhantomData<(T, P)>, } fn print_nums_readonly(query: Query<NumQuery<u64, i64>, NumQueryFilter<u64, i64>>) { for num in query.iter() { println!("{:#?}", num); } } #[derive(WorldQuery)] #[world_query(mutable, derive(Debug))] struct MutNumQuery<'w, T: Component, P: Component> { i_16: &'w mut i16, i_32_opt: Option<&'w mut i32>, } fn print_nums(mut query: Query<MutNumQuery, NumQueryFilter<u64, i64>>) { for num in query.iter_mut() { println!("{:#?}", num); } } ``` ## TODOs: - [x] Add support for `&T` and `&mut T` - [x] Test - [x] Add support for optional types - [x] Test - [x] Add support for `Entity` - [x] Test - [x] Add support for nested `WorldQuery` - [x] Test - [x] Add support for tuples - [x] Test - [x] Add support for generics - [x] Test - [x] Add support for query filters - [x] Test - [x] Add support for `PhantomData` - [x] Test - [x] Refactor `read_world_query_field_type_info` - [x] Properly document `readonly` attribute for nested queries and the static assertions that guarantee safety - [x] Test that we never implement `ReadOnlyFetch` for types that need mutable access - [x] Test that we insert static assertions for nested `WorldQuery` that a user marked as readonly
2022-02-24 00:19:49 +00:00
[package.metadata.example.custom_query_param]
name = "Custom Query Parameters"
description = "Groups commonly used compound queries and query filters into a single type"
category = "ECS (Entity Component System)"
wasm = false
2020-05-01 20:12:47 +00:00
[[example]]
name = "event"
path = "examples/ecs/event.rs"
doc-scrape-examples = true
2020-05-01 20:12:47 +00:00
[package.metadata.example.event]
name = "Event"
description = "Illustrates event creation, activation, and reception"
category = "ECS (Entity Component System)"
wasm = false
2020-12-13 02:04:42 +00:00
[[example]]
name = "fixed_timestep"
path = "examples/ecs/fixed_timestep.rs"
doc-scrape-examples = true
2020-12-13 02:04:42 +00:00
[package.metadata.example.fixed_timestep]
name = "Fixed Timestep"
description = "Shows how to create systems that run every fixed timestep, rather than every tick"
category = "ECS (Entity Component System)"
wasm = false
[[example]]
name = "generic_system"
path = "examples/ecs/generic_system.rs"
doc-scrape-examples = true
[package.metadata.example.generic_system]
name = "Generic System"
description = "Shows how to create systems that can be reused with different types"
category = "ECS (Entity Component System)"
wasm = false
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[[example]]
name = "hierarchy"
path = "examples/ecs/hierarchy.rs"
doc-scrape-examples = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[package.metadata.example.hierarchy]
name = "Hierarchy"
description = "Creates a hierarchy of parents and children entities"
category = "ECS (Entity Component System)"
wasm = false
[[example]]
name = "iter_combinations"
path = "examples/ecs/iter_combinations.rs"
doc-scrape-examples = true
[package.metadata.example.iter_combinations]
name = "Iter Combinations"
description = "Shows how to iterate over combinations of query results"
category = "ECS (Entity Component System)"
wasm = true
One Shot Systems (#8963) I'm adopting this ~~child~~ PR. # Objective - Working with exclusive world access is not always easy: in many cases, a standard system or three is more ergonomic to write, and more modularly maintainable. - For small, one-off tasks (commonly handled with scripting), running an event-reader system incurs a small but flat overhead cost and muddies the schedule. - Certain forms of logic (e.g. turn-based games) want very fine-grained linear and/or branching control over logic. - SystemState is not automatically cached, and so performance can suffer and change detection breaks. - Fixes https://github.com/bevyengine/bevy/issues/2192. - Partial workaround for https://github.com/bevyengine/bevy/issues/279. ## Solution - Adds a SystemRegistry resource to the World, which stores initialized systems keyed by their SystemSet. - Allows users to call world.run_system(my_system) and commands.run_system(my_system), without re-initializing or losing state (essential for change detection). - Add a Callback type to enable convenient use of dynamic one shot systems and reduce the mental overhead of working with Box<dyn SystemSet>. - Allow users to run systems based on their SystemSet, enabling more complex user-made abstractions. ## Future work - Parameterized one-shot systems would improve reusability and bring them closer to events and commands. The API could be something like run_system_with_input(my_system, my_input) and use the In SystemParam. - We should evaluate the unification of commands and one-shot systems since they are two different ways to run logic on demand over a World. ### Prior attempts - https://github.com/bevyengine/bevy/pull/2234 - https://github.com/bevyengine/bevy/pull/2417 - https://github.com/bevyengine/bevy/pull/4090 - https://github.com/bevyengine/bevy/pull/7999 This PR continues the work done in https://github.com/bevyengine/bevy/pull/7999. --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> Co-authored-by: Federico Rinaldi <gisquerin@gmail.com> Co-authored-by: MinerSebas <66798382+MinerSebas@users.noreply.github.com> Co-authored-by: Aevyrie <aevyrie@gmail.com> Co-authored-by: Alejandro Pascual Pozo <alejandro.pascual.pozo@gmail.com> Co-authored-by: Rob Parrett <robparrett@gmail.com> Co-authored-by: François <mockersf@gmail.com> Co-authored-by: Dmytro Banin <banind@cs.washington.edu> Co-authored-by: James Liu <contact@jamessliu.com>
2023-09-19 20:17:05 +00:00
[[example]]
name = "one_shot_systems"
path = "examples/ecs/one_shot_systems.rs"
[package.metadata.example.one_shot_systems]
name = "One Shot Systems"
description = "Shows how to flexibly run systems without scheduling them"
category = "ECS (Entity Component System)"
wasm = false
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[[example]]
name = "parallel_query"
path = "examples/ecs/parallel_query.rs"
doc-scrape-examples = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[package.metadata.example.parallel_query]
name = "Parallel Query"
description = "Illustrates parallel queries with `ParallelIterator`"
category = "ECS (Entity Component System)"
wasm = false
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[[example]]
name = "removal_detection"
path = "examples/ecs/removal_detection.rs"
doc-scrape-examples = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[package.metadata.example.removal_detection]
name = "Removal Detection"
Migrate engine to Schedule v3 (#7267) Huge thanks to @maniwani, @devil-ira, @hymm, @cart, @superdump and @jakobhellermann for the help with this PR. # Objective - Followup #6587. - Minimal integration for the Stageless Scheduling RFC: https://github.com/bevyengine/rfcs/pull/45 ## Solution - [x] Remove old scheduling module - [x] Migrate new methods to no longer use extension methods - [x] Fix compiler errors - [x] Fix benchmarks - [x] Fix examples - [x] Fix docs - [x] Fix tests ## Changelog ### Added - a large number of methods on `App` to work with schedules ergonomically - the `CoreSchedule` enum - `App::add_extract_system` via the `RenderingAppExtension` trait extension method - the private `prepare_view_uniforms` system now has a public system set for scheduling purposes, called `ViewSet::PrepareUniforms` ### Removed - stages, and all code that mentions stages - states have been dramatically simplified, and no longer use a stack - `RunCriteriaLabel` - `AsSystemLabel` trait - `on_hierarchy_reports_enabled` run criteria (now just uses an ad hoc resource checking run condition) - systems in `RenderSet/Stage::Extract` no longer warn when they do not read data from the main world - `RunCriteriaLabel` - `transform_propagate_system_set`: this was a nonstandard pattern that didn't actually provide enough control. The systems are already `pub`: the docs have been updated to ensure that the third-party usage is clear. ### Changed - `System::default_labels` is now `System::default_system_sets`. - `App::add_default_labels` is now `App::add_default_sets` - `CoreStage` and `StartupStage` enums are now `CoreSet` and `StartupSet` - `App::add_system_set` was renamed to `App::add_systems` - The `StartupSchedule` label is now defined as part of the `CoreSchedules` enum - `.label(SystemLabel)` is now referred to as `.in_set(SystemSet)` - `SystemLabel` trait was replaced by `SystemSet` - `SystemTypeIdLabel<T>` was replaced by `SystemSetType<T>` - The `ReportHierarchyIssue` resource now has a public constructor (`new`), and implements `PartialEq` - Fixed time steps now use a schedule (`CoreSchedule::FixedTimeStep`) rather than a run criteria. - Adding rendering extraction systems now panics rather than silently failing if no subapp with the `RenderApp` label is found. - the `calculate_bounds` system, with the `CalculateBounds` label, is now in `CoreSet::Update`, rather than in `CoreSet::PostUpdate` before commands are applied. - `SceneSpawnerSystem` now runs under `CoreSet::Update`, rather than `CoreStage::PreUpdate.at_end()`. - `bevy_pbr::add_clusters` is no longer an exclusive system - the top level `bevy_ecs::schedule` module was replaced with `bevy_ecs::scheduling` - `tick_global_task_pools_on_main_thread` is no longer run as an exclusive system. Instead, it has been replaced by `tick_global_task_pools`, which uses a `NonSend` resource to force running on the main thread. ## Migration Guide - Calls to `.label(MyLabel)` should be replaced with `.in_set(MySet)` - Stages have been removed. Replace these with system sets, and then add command flushes using the `apply_system_buffers` exclusive system where needed. - The `CoreStage`, `StartupStage, `RenderStage` and `AssetStage` enums have been replaced with `CoreSet`, `StartupSet, `RenderSet` and `AssetSet`. The same scheduling guarantees have been preserved. - Systems are no longer added to `CoreSet::Update` by default. Add systems manually if this behavior is needed, although you should consider adding your game logic systems to `CoreSchedule::FixedTimestep` instead for more reliable framerate-independent behavior. - Similarly, startup systems are no longer part of `StartupSet::Startup` by default. In most cases, this won't matter to you. - For example, `add_system_to_stage(CoreStage::PostUpdate, my_system)` should be replaced with - `add_system(my_system.in_set(CoreSet::PostUpdate)` - When testing systems or otherwise running them in a headless fashion, simply construct and run a schedule using `Schedule::new()` and `World::run_schedule` rather than constructing stages - Run criteria have been renamed to run conditions. These can now be combined with each other and with states. - Looping run criteria and state stacks have been removed. Use an exclusive system that runs a schedule if you need this level of control over system control flow. - For app-level control flow over which schedules get run when (such as for rollback networking), create your own schedule and insert it under the `CoreSchedule::Outer` label. - Fixed timesteps are now evaluated in a schedule, rather than controlled via run criteria. The `run_fixed_timestep` system runs this schedule between `CoreSet::First` and `CoreSet::PreUpdate` by default. - Command flush points introduced by `AssetStage` have been removed. If you were relying on these, add them back manually. - Adding extract systems is now typically done directly on the main app. Make sure the `RenderingAppExtension` trait is in scope, then call `app.add_extract_system(my_system)`. - the `calculate_bounds` system, with the `CalculateBounds` label, is now in `CoreSet::Update`, rather than in `CoreSet::PostUpdate` before commands are applied. You may need to order your movement systems to occur before this system in order to avoid system order ambiguities in culling behavior. - the `RenderLabel` `AppLabel` was renamed to `RenderApp` for clarity - `App::add_state` now takes 0 arguments: the starting state is set based on the `Default` impl. - Instead of creating `SystemSet` containers for systems that run in stages, simply use `.on_enter::<State::Variant>()` or its `on_exit` or `on_update` siblings. - `SystemLabel` derives should be replaced with `SystemSet`. You will also need to add the `Debug`, `PartialEq`, `Eq`, and `Hash` traits to satisfy the new trait bounds. - `with_run_criteria` has been renamed to `run_if`. Run criteria have been renamed to run conditions for clarity, and should now simply return a bool. - States have been dramatically simplified: there is no longer a "state stack". To queue a transition to the next state, call `NextState::set` ## TODO - [x] remove dead methods on App and World - [x] add `App::add_system_to_schedule` and `App::add_systems_to_schedule` - [x] avoid adding the default system set at inappropriate times - [x] remove any accidental cycles in the default plugins schedule - [x] migrate benchmarks - [x] expose explicit labels for the built-in command flush points - [x] migrate engine code - [x] remove all mentions of stages from the docs - [x] verify docs for States - [x] fix uses of exclusive systems that use .end / .at_start / .before_commands - [x] migrate RenderStage and AssetStage - [x] migrate examples - [x] ensure that transform propagation is exported in a sufficiently public way (the systems are already pub) - [x] ensure that on_enter schedules are run at least once before the main app - [x] re-enable opt-in to execution order ambiguities - [x] revert change to `update_bounds` to ensure it runs in `PostUpdate` - [x] test all examples - [x] unbreak directional lights - [x] unbreak shadows (see 3d_scene, 3d_shape, lighting, transparaency_3d examples) - [x] game menu example shows loading screen and menu simultaneously - [x] display settings menu is a blank screen - [x] `without_winit` example panics - [x] ensure all tests pass - [x] SubApp doc test fails - [x] runs_spawn_local tasks fails - [x] [Fix panic_when_hierachy_cycle test hanging](https://github.com/alice-i-cecile/bevy/pull/120) ## Points of Difficulty and Controversy **Reviewers, please give feedback on these and look closely** 1. Default sets, from the RFC, have been removed. These added a tremendous amount of implicit complexity and result in hard to debug scheduling errors. They're going to be tackled in the form of "base sets" by @cart in a followup. 2. The outer schedule controls which schedule is run when `App::update` is called. 3. I implemented `Label for `Box<dyn Label>` for our label types. This enables us to store schedule labels in concrete form, and then later run them. I ran into the same set of problems when working with one-shot systems. We've previously investigated this pattern in depth, and it does not appear to lead to extra indirection with nested boxes. 4. `SubApp::update` simply runs the default schedule once. This sucks, but this whole API is incomplete and this was the minimal changeset. 5. `time_system` and `tick_global_task_pools_on_main_thread` no longer use exclusive systems to attempt to force scheduling order 6. Implemetnation strategy for fixed timesteps 7. `AssetStage` was migrated to `AssetSet` without reintroducing command flush points. These did not appear to be used, and it's nice to remove these bottlenecks. 8. Migration of `bevy_render/lib.rs` and pipelined rendering. The logic here is unusually tricky, as we have complex scheduling requirements. ## Future Work (ideally before 0.10) - Rename schedule_v3 module to schedule or scheduling - Add a derive macro to states, and likely a `EnumIter` trait of some form - Figure out what exactly to do with the "systems added should basically work by default" problem - Improve ergonomics for working with fixed timesteps and states - Polish FixedTime API to match Time - Rebase and merge #7415 - Resolve all internal ambiguities (blocked on better tools, especially #7442) - Add "base sets" to replace the removed default sets.
2023-02-06 02:04:50 +00:00
description = "Query for entities that had a specific component removed earlier in the current frame"
category = "ECS (Entity Component System)"
wasm = false
[[example]]
name = "run_conditions"
path = "examples/ecs/run_conditions.rs"
doc-scrape-examples = true
[package.metadata.example.run_conditions]
name = "Run Conditions"
description = "Run systems only when one or multiple conditions are met"
category = "ECS (Entity Component System)"
wasm = false
2020-05-01 20:12:47 +00:00
[[example]]
name = "startup_system"
path = "examples/ecs/startup_system.rs"
doc-scrape-examples = true
2020-05-01 20:12:47 +00:00
[package.metadata.example.startup_system]
name = "Startup System"
description = "Demonstrates a startup system (one that runs once when the app starts up)"
category = "ECS (Entity Component System)"
wasm = false
2020-12-13 02:04:42 +00:00
[[example]]
name = "state"
path = "examples/ecs/state.rs"
doc-scrape-examples = true
2020-12-13 02:04:42 +00:00
[package.metadata.example.state]
name = "State"
description = "Illustrates how to use States to control transitioning from a Menu state to an InGame state"
category = "ECS (Entity Component System)"
wasm = false
[[example]]
name = "system_piping"
path = "examples/ecs/system_piping.rs"
doc-scrape-examples = true
[package.metadata.example.system_piping]
name = "System Piping"
description = "Pipe the output of one system into a second, allowing you to handle any errors gracefully"
category = "ECS (Entity Component System)"
wasm = false
[[example]]
name = "system_closure"
path = "examples/ecs/system_closure.rs"
doc-scrape-examples = true
[package.metadata.example.system_closure]
name = "System Closure"
description = "Show how to use closures as systems, and how to configure `Local` variables by capturing external state"
category = "ECS (Entity Component System)"
wasm = false
[[example]]
name = "system_param"
path = "examples/ecs/system_param.rs"
doc-scrape-examples = true
[package.metadata.example.system_param]
name = "System Parameter"
description = "Illustrates creating custom system parameters with `SystemParam`"
category = "ECS (Entity Component System)"
wasm = false
# Time
Unify `FixedTime` and `Time` while fixing several problems (#8964) # Objective Current `FixedTime` and `Time` have several problems. This pull aims to fix many of them at once. - If there is a longer pause between app updates, time will jump forward a lot at once and fixed time will iterate on `FixedUpdate` for a large number of steps. If the pause is merely seconds, then this will just mean jerkiness and possible unexpected behaviour in gameplay. If the pause is hours/days as with OS suspend, the game will appear to freeze until it has caught up with real time. - If calculating a fixed step takes longer than specified fixed step period, the game will enter a death spiral where rendering each frame takes longer and longer due to more and more fixed step updates being run per frame and the game appears to freeze. - There is no way to see current fixed step elapsed time inside fixed steps. In order to track this, the game designer needs to add a custom system inside `FixedUpdate` that calculates elapsed or step count in a resource. - Access to delta time inside fixed step is `FixedStep::period` rather than `Time::delta`. This, coupled with the issue that `Time::elapsed` isn't available at all for fixed steps, makes it that time requiring systems are either implemented to be run in `FixedUpdate` or `Update`, but rarely work in both. - Fixes #8800 - Fixes #8543 - Fixes #7439 - Fixes #5692 ## Solution - Create a generic `Time<T>` clock that has no processing logic but which can be instantiated for multiple usages. This is also exposed for users to add custom clocks. - Create three standard clocks, `Time<Real>`, `Time<Virtual>` and `Time<Fixed>`, all of which contain their individual logic. - Create one "default" clock, which is just `Time` (or `Time<()>`), which will be overwritten from `Time<Virtual>` on each update, and `Time<Fixed>` inside `FixedUpdate` schedule. This way systems that do not care specifically which time they track can work both in `Update` and `FixedUpdate` without changes and the behaviour is intuitive. - Add `max_delta` to virtual time update, which limits how much can be added to virtual time by a single update. This fixes both the behaviour after a long freeze, and also the death spiral by limiting how many fixed timestep iterations there can be per update. Possible future work could be adding `max_accumulator` to add a sort of "leaky bucket" time processing to possibly smooth out jumps in time while keeping frame rate stable. - Many minor tweaks and clarifications to the time functions and their documentation. ## Changelog - `Time::raw_delta()`, `Time::raw_elapsed()` and related methods are moved to `Time<Real>::delta()` and `Time<Real>::elapsed()` and now match `Time` API - `FixedTime` is now `Time<Fixed>` and matches `Time` API. - `Time<Fixed>` default timestep is now 64 Hz, or 15625 microseconds. - `Time` inside `FixedUpdate` now reflects fixed timestep time, making systems portable between `Update ` and `FixedUpdate`. - `Time::pause()`, `Time::set_relative_speed()` and related methods must now be called as `Time<Virtual>::pause()` etc. - There is a new `max_delta` setting in `Time<Virtual>` that limits how much the clock can jump by a single update. The default value is 0.25 seconds. - Removed `on_fixed_timer()` condition as `on_timer()` does the right thing inside `FixedUpdate` now. ## Migration Guide - Change all `Res<Time>` instances that access `raw_delta()`, `raw_elapsed()` and related methods to `Res<Time<Real>>` and `delta()`, `elapsed()`, etc. - Change access to `period` from `Res<FixedTime>` to `Res<Time<Fixed>>` and use `delta()`. - The default timestep has been changed from 60 Hz to 64 Hz. If you wish to restore the old behaviour, use `app.insert_resource(Time::<Fixed>::from_hz(60.0))`. - Change `app.insert_resource(FixedTime::new(duration))` to `app.insert_resource(Time::<Fixed>::from_duration(duration))` - Change `app.insert_resource(FixedTime::new_from_secs(secs))` to `app.insert_resource(Time::<Fixed>::from_seconds(secs))` - Change `system.on_fixed_timer(duration)` to `system.on_timer(duration)`. Timers in systems placed in `FixedUpdate` schedule automatically use the fixed time clock. - Change `ResMut<Time>` calls to `pause()`, `is_paused()`, `set_relative_speed()` and related methods to `ResMut<Time<Virtual>>` calls. The API is the same, with the exception that `relative_speed()` will return the actual last ste relative speed, while `effective_relative_speed()` returns 0.0 if the time is paused and corresponds to the speed that was set when the update for the current frame started. ## Todo - [x] Update pull name and description - [x] Top level documentation on usage - [x] Fix examples - [x] Decide on default `max_delta` value - [x] Decide naming of the three clocks: is `Real`, `Virtual`, `Fixed` good? - [x] Decide if the three clock inner structures should be in prelude - [x] Decide on best way to configure values at startup: is manually inserting a new clock instance okay, or should there be config struct separately? - [x] Fix links in docs - [x] Decide what should be public and what not - [x] Decide how `wrap_period` should be handled when it is changed - [x] ~~Add toggles to disable setting the clock as default?~~ No, separate pull if needed. - [x] Add tests - [x] Reformat, ensure adheres to conventions etc. - [x] Build documentation and see that it looks correct ## Contributors Huge thanks to @alice-i-cecile and @maniwani while building this pull. It was a shared effort! --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> Co-authored-by: Cameron <51241057+maniwani@users.noreply.github.com> Co-authored-by: Jerome Humbert <djeedai@gmail.com>
2023-10-16 01:57:55 +00:00
[[example]]
name = "time"
path = "examples/time/time.rs"
Unify `FixedTime` and `Time` while fixing several problems (#8964) # Objective Current `FixedTime` and `Time` have several problems. This pull aims to fix many of them at once. - If there is a longer pause between app updates, time will jump forward a lot at once and fixed time will iterate on `FixedUpdate` for a large number of steps. If the pause is merely seconds, then this will just mean jerkiness and possible unexpected behaviour in gameplay. If the pause is hours/days as with OS suspend, the game will appear to freeze until it has caught up with real time. - If calculating a fixed step takes longer than specified fixed step period, the game will enter a death spiral where rendering each frame takes longer and longer due to more and more fixed step updates being run per frame and the game appears to freeze. - There is no way to see current fixed step elapsed time inside fixed steps. In order to track this, the game designer needs to add a custom system inside `FixedUpdate` that calculates elapsed or step count in a resource. - Access to delta time inside fixed step is `FixedStep::period` rather than `Time::delta`. This, coupled with the issue that `Time::elapsed` isn't available at all for fixed steps, makes it that time requiring systems are either implemented to be run in `FixedUpdate` or `Update`, but rarely work in both. - Fixes #8800 - Fixes #8543 - Fixes #7439 - Fixes #5692 ## Solution - Create a generic `Time<T>` clock that has no processing logic but which can be instantiated for multiple usages. This is also exposed for users to add custom clocks. - Create three standard clocks, `Time<Real>`, `Time<Virtual>` and `Time<Fixed>`, all of which contain their individual logic. - Create one "default" clock, which is just `Time` (or `Time<()>`), which will be overwritten from `Time<Virtual>` on each update, and `Time<Fixed>` inside `FixedUpdate` schedule. This way systems that do not care specifically which time they track can work both in `Update` and `FixedUpdate` without changes and the behaviour is intuitive. - Add `max_delta` to virtual time update, which limits how much can be added to virtual time by a single update. This fixes both the behaviour after a long freeze, and also the death spiral by limiting how many fixed timestep iterations there can be per update. Possible future work could be adding `max_accumulator` to add a sort of "leaky bucket" time processing to possibly smooth out jumps in time while keeping frame rate stable. - Many minor tweaks and clarifications to the time functions and their documentation. ## Changelog - `Time::raw_delta()`, `Time::raw_elapsed()` and related methods are moved to `Time<Real>::delta()` and `Time<Real>::elapsed()` and now match `Time` API - `FixedTime` is now `Time<Fixed>` and matches `Time` API. - `Time<Fixed>` default timestep is now 64 Hz, or 15625 microseconds. - `Time` inside `FixedUpdate` now reflects fixed timestep time, making systems portable between `Update ` and `FixedUpdate`. - `Time::pause()`, `Time::set_relative_speed()` and related methods must now be called as `Time<Virtual>::pause()` etc. - There is a new `max_delta` setting in `Time<Virtual>` that limits how much the clock can jump by a single update. The default value is 0.25 seconds. - Removed `on_fixed_timer()` condition as `on_timer()` does the right thing inside `FixedUpdate` now. ## Migration Guide - Change all `Res<Time>` instances that access `raw_delta()`, `raw_elapsed()` and related methods to `Res<Time<Real>>` and `delta()`, `elapsed()`, etc. - Change access to `period` from `Res<FixedTime>` to `Res<Time<Fixed>>` and use `delta()`. - The default timestep has been changed from 60 Hz to 64 Hz. If you wish to restore the old behaviour, use `app.insert_resource(Time::<Fixed>::from_hz(60.0))`. - Change `app.insert_resource(FixedTime::new(duration))` to `app.insert_resource(Time::<Fixed>::from_duration(duration))` - Change `app.insert_resource(FixedTime::new_from_secs(secs))` to `app.insert_resource(Time::<Fixed>::from_seconds(secs))` - Change `system.on_fixed_timer(duration)` to `system.on_timer(duration)`. Timers in systems placed in `FixedUpdate` schedule automatically use the fixed time clock. - Change `ResMut<Time>` calls to `pause()`, `is_paused()`, `set_relative_speed()` and related methods to `ResMut<Time<Virtual>>` calls. The API is the same, with the exception that `relative_speed()` will return the actual last ste relative speed, while `effective_relative_speed()` returns 0.0 if the time is paused and corresponds to the speed that was set when the update for the current frame started. ## Todo - [x] Update pull name and description - [x] Top level documentation on usage - [x] Fix examples - [x] Decide on default `max_delta` value - [x] Decide naming of the three clocks: is `Real`, `Virtual`, `Fixed` good? - [x] Decide if the three clock inner structures should be in prelude - [x] Decide on best way to configure values at startup: is manually inserting a new clock instance okay, or should there be config struct separately? - [x] Fix links in docs - [x] Decide what should be public and what not - [x] Decide how `wrap_period` should be handled when it is changed - [x] ~~Add toggles to disable setting the clock as default?~~ No, separate pull if needed. - [x] Add tests - [x] Reformat, ensure adheres to conventions etc. - [x] Build documentation and see that it looks correct ## Contributors Huge thanks to @alice-i-cecile and @maniwani while building this pull. It was a shared effort! --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> Co-authored-by: Cameron <51241057+maniwani@users.noreply.github.com> Co-authored-by: Jerome Humbert <djeedai@gmail.com>
2023-10-16 01:57:55 +00:00
[package.metadata.example.time]
name = "Time handling"
description = "Explains how Time is handled in ECS"
category = "Time"
wasm = false
[[example]]
name = "virtual_time"
path = "examples/time/virtual_time.rs"
[package.metadata.example.virtual_time]
name = "Virtual time"
description = "Shows how `Time<Virtual>` can be used to pause, resume, slow down and speed up a game."
category = "Time"
Unify `FixedTime` and `Time` while fixing several problems (#8964) # Objective Current `FixedTime` and `Time` have several problems. This pull aims to fix many of them at once. - If there is a longer pause between app updates, time will jump forward a lot at once and fixed time will iterate on `FixedUpdate` for a large number of steps. If the pause is merely seconds, then this will just mean jerkiness and possible unexpected behaviour in gameplay. If the pause is hours/days as with OS suspend, the game will appear to freeze until it has caught up with real time. - If calculating a fixed step takes longer than specified fixed step period, the game will enter a death spiral where rendering each frame takes longer and longer due to more and more fixed step updates being run per frame and the game appears to freeze. - There is no way to see current fixed step elapsed time inside fixed steps. In order to track this, the game designer needs to add a custom system inside `FixedUpdate` that calculates elapsed or step count in a resource. - Access to delta time inside fixed step is `FixedStep::period` rather than `Time::delta`. This, coupled with the issue that `Time::elapsed` isn't available at all for fixed steps, makes it that time requiring systems are either implemented to be run in `FixedUpdate` or `Update`, but rarely work in both. - Fixes #8800 - Fixes #8543 - Fixes #7439 - Fixes #5692 ## Solution - Create a generic `Time<T>` clock that has no processing logic but which can be instantiated for multiple usages. This is also exposed for users to add custom clocks. - Create three standard clocks, `Time<Real>`, `Time<Virtual>` and `Time<Fixed>`, all of which contain their individual logic. - Create one "default" clock, which is just `Time` (or `Time<()>`), which will be overwritten from `Time<Virtual>` on each update, and `Time<Fixed>` inside `FixedUpdate` schedule. This way systems that do not care specifically which time they track can work both in `Update` and `FixedUpdate` without changes and the behaviour is intuitive. - Add `max_delta` to virtual time update, which limits how much can be added to virtual time by a single update. This fixes both the behaviour after a long freeze, and also the death spiral by limiting how many fixed timestep iterations there can be per update. Possible future work could be adding `max_accumulator` to add a sort of "leaky bucket" time processing to possibly smooth out jumps in time while keeping frame rate stable. - Many minor tweaks and clarifications to the time functions and their documentation. ## Changelog - `Time::raw_delta()`, `Time::raw_elapsed()` and related methods are moved to `Time<Real>::delta()` and `Time<Real>::elapsed()` and now match `Time` API - `FixedTime` is now `Time<Fixed>` and matches `Time` API. - `Time<Fixed>` default timestep is now 64 Hz, or 15625 microseconds. - `Time` inside `FixedUpdate` now reflects fixed timestep time, making systems portable between `Update ` and `FixedUpdate`. - `Time::pause()`, `Time::set_relative_speed()` and related methods must now be called as `Time<Virtual>::pause()` etc. - There is a new `max_delta` setting in `Time<Virtual>` that limits how much the clock can jump by a single update. The default value is 0.25 seconds. - Removed `on_fixed_timer()` condition as `on_timer()` does the right thing inside `FixedUpdate` now. ## Migration Guide - Change all `Res<Time>` instances that access `raw_delta()`, `raw_elapsed()` and related methods to `Res<Time<Real>>` and `delta()`, `elapsed()`, etc. - Change access to `period` from `Res<FixedTime>` to `Res<Time<Fixed>>` and use `delta()`. - The default timestep has been changed from 60 Hz to 64 Hz. If you wish to restore the old behaviour, use `app.insert_resource(Time::<Fixed>::from_hz(60.0))`. - Change `app.insert_resource(FixedTime::new(duration))` to `app.insert_resource(Time::<Fixed>::from_duration(duration))` - Change `app.insert_resource(FixedTime::new_from_secs(secs))` to `app.insert_resource(Time::<Fixed>::from_seconds(secs))` - Change `system.on_fixed_timer(duration)` to `system.on_timer(duration)`. Timers in systems placed in `FixedUpdate` schedule automatically use the fixed time clock. - Change `ResMut<Time>` calls to `pause()`, `is_paused()`, `set_relative_speed()` and related methods to `ResMut<Time<Virtual>>` calls. The API is the same, with the exception that `relative_speed()` will return the actual last ste relative speed, while `effective_relative_speed()` returns 0.0 if the time is paused and corresponds to the speed that was set when the update for the current frame started. ## Todo - [x] Update pull name and description - [x] Top level documentation on usage - [x] Fix examples - [x] Decide on default `max_delta` value - [x] Decide naming of the three clocks: is `Real`, `Virtual`, `Fixed` good? - [x] Decide if the three clock inner structures should be in prelude - [x] Decide on best way to configure values at startup: is manually inserting a new clock instance okay, or should there be config struct separately? - [x] Fix links in docs - [x] Decide what should be public and what not - [x] Decide how `wrap_period` should be handled when it is changed - [x] ~~Add toggles to disable setting the clock as default?~~ No, separate pull if needed. - [x] Add tests - [x] Reformat, ensure adheres to conventions etc. - [x] Build documentation and see that it looks correct ## Contributors Huge thanks to @alice-i-cecile and @maniwani while building this pull. It was a shared effort! --------- Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> Co-authored-by: Cameron <51241057+maniwani@users.noreply.github.com> Co-authored-by: Jerome Humbert <djeedai@gmail.com>
2023-10-16 01:57:55 +00:00
wasm = false
[[example]]
name = "timers"
path = "examples/time/timers.rs"
doc-scrape-examples = true
[package.metadata.example.timers]
name = "Timers"
description = "Illustrates ticking `Timer` resources inside systems and handling their state"
category = "Time"
wasm = false
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
# Games
[[example]]
name = "alien_cake_addict"
path = "examples/games/alien_cake_addict.rs"
doc-scrape-examples = true
[package.metadata.example.alien_cake_addict]
name = "Alien Cake Addict"
description = "Eat the cakes. Eat them all. An example 3D game"
category = "Games"
wasm = true
2020-06-27 04:40:09 +00:00
[[example]]
name = "breakout"
path = "examples/games/breakout.rs"
doc-scrape-examples = true
[package.metadata.example.breakout]
name = "Breakout"
description = "An implementation of the classic game \"Breakout\""
category = "Games"
wasm = true
[[example]]
name = "contributors"
path = "examples/games/contributors.rs"
doc-scrape-examples = true
2020-06-27 04:40:09 +00:00
[package.metadata.example.contributors]
name = "Contributors"
description = "Displays each contributor as a bouncy bevy-ball!"
category = "Games"
wasm = true
[[example]]
name = "game_menu"
path = "examples/games/game_menu.rs"
doc-scrape-examples = true
[package.metadata.example.game_menu]
name = "Game Menu"
description = "A simple game menu"
category = "Games"
wasm = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
# Input
2020-05-01 20:12:47 +00:00
[[example]]
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
name = "char_input_events"
path = "examples/input/char_input_events.rs"
doc-scrape-examples = true
2020-05-01 20:12:47 +00:00
[package.metadata.example.char_input_events]
name = "Char Input Events"
description = "Prints out all chars as they are inputted"
category = "Input"
wasm = false
2020-05-01 20:12:47 +00:00
[[example]]
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
name = "gamepad_input"
path = "examples/input/gamepad_input.rs"
doc-scrape-examples = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[package.metadata.example.gamepad_input]
name = "Gamepad Input"
description = "Shows handling of gamepad input, connections, and disconnections"
category = "Input"
wasm = false
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[[example]]
name = "gamepad_input_events"
path = "examples/input/gamepad_input_events.rs"
doc-scrape-examples = true
2020-06-05 06:49:36 +00:00
[package.metadata.example.gamepad_input_events]
name = "Gamepad Input Events"
description = "Iterates and prints gamepad input and connection events"
category = "Input"
wasm = false
[[example]]
name = "gamepad_rumble"
path = "examples/input/gamepad_rumble.rs"
doc-scrape-examples = true
[package.metadata.example.gamepad_rumble]
name = "Gamepad Rumble"
description = "Shows how to rumble a gamepad using force feedback"
category = "Input"
wasm = false
2020-06-05 06:49:36 +00:00
[[example]]
name = "keyboard_input"
path = "examples/input/keyboard_input.rs"
doc-scrape-examples = true
2020-06-05 06:49:36 +00:00
[package.metadata.example.keyboard_input]
name = "Keyboard Input"
description = "Demonstrates handling a key press/release"
category = "Input"
wasm = false
[[example]]
name = "keyboard_modifiers"
path = "examples/input/keyboard_modifiers.rs"
doc-scrape-examples = true
[package.metadata.example.keyboard_modifiers]
name = "Keyboard Modifiers"
description = "Demonstrates using key modifiers (ctrl, shift)"
category = "Input"
wasm = false
2020-06-05 06:49:36 +00:00
[[example]]
name = "keyboard_input_events"
path = "examples/input/keyboard_input_events.rs"
doc-scrape-examples = true
2020-05-01 20:12:47 +00:00
[package.metadata.example.keyboard_input_events]
name = "Keyboard Input Events"
description = "Prints out all keyboard events"
category = "Input"
wasm = false
[[example]]
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
name = "mouse_input"
path = "examples/input/mouse_input.rs"
doc-scrape-examples = true
[package.metadata.example.mouse_input]
name = "Mouse Input"
description = "Demonstrates handling a mouse button press/release"
category = "Input"
wasm = false
[[example]]
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
name = "mouse_input_events"
path = "examples/input/mouse_input_events.rs"
doc-scrape-examples = true
[package.metadata.example.mouse_input_events]
name = "Mouse Input Events"
description = "Prints out all mouse events (buttons, movement, etc.)"
category = "Input"
wasm = false
[[example]]
name = "mouse_grab"
path = "examples/input/mouse_grab.rs"
doc-scrape-examples = true
[package.metadata.example.mouse_grab]
name = "Mouse Grab"
description = "Demonstrates how to grab the mouse, locking the cursor to the app's screen"
category = "Input"
wasm = false
[[example]]
name = "touch_input"
path = "examples/input/touch_input.rs"
doc-scrape-examples = true
[package.metadata.example.touch_input]
name = "Touch Input"
description = "Displays touch presses, releases, and cancels"
category = "Input"
wasm = false
[[example]]
name = "touch_input_events"
path = "examples/input/touch_input_events.rs"
doc-scrape-examples = true
[package.metadata.example.touch_input_events]
name = "Touch Input Events"
description = "Prints out all touch inputs"
category = "Input"
wasm = false
[[example]]
name = "text_input"
path = "examples/input/text_input.rs"
doc-scrape-examples = true
[package.metadata.example.text_input]
name = "Text Input"
description = "Simple text input with IME support"
category = "Input"
wasm = false
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
# Reflection
2020-05-01 20:12:47 +00:00
[[example]]
2020-11-28 00:39:59 +00:00
name = "reflection"
path = "examples/reflection/reflection.rs"
doc-scrape-examples = true
2020-11-28 00:39:59 +00:00
[package.metadata.example.reflection]
name = "Reflection"
description = "Demonstrates how reflection in Bevy provides a way to dynamically interact with Rust types"
category = "Reflection"
wasm = false
2020-11-28 00:39:59 +00:00
[[example]]
name = "generic_reflection"
path = "examples/reflection/generic_reflection.rs"
doc-scrape-examples = true
2020-11-28 00:39:59 +00:00
[package.metadata.example.generic_reflection]
name = "Generic Reflection"
description = "Registers concrete instances of generic types that may be used with reflection"
category = "Reflection"
wasm = false
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[[example]]
name = "reflection_types"
path = "examples/reflection/reflection_types.rs"
doc-scrape-examples = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[package.metadata.example.reflection_types]
name = "Reflection Types"
description = "Illustrates the various reflection types available"
category = "Reflection"
wasm = false
2020-11-28 00:39:59 +00:00
[[example]]
name = "trait_reflection"
path = "examples/reflection/trait_reflection.rs"
doc-scrape-examples = true
2020-05-01 20:12:47 +00:00
[package.metadata.example.trait_reflection]
name = "Trait Reflection"
description = "Allows reflection with trait objects"
category = "Reflection"
wasm = false
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
# Scene
2020-05-22 06:58:11 +00:00
[[example]]
2020-11-28 00:39:59 +00:00
name = "scene"
path = "examples/scene/scene.rs"
doc-scrape-examples = true
2020-05-22 06:58:11 +00:00
[package.metadata.example.scene]
name = "Scene"
description = "Demonstrates loading from and saving scenes to files"
category = "Scene"
wasm = false
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
# Shaders
[[package.metadata.example_category]]
name = "Shaders"
description = """
These examples demonstrate how to implement different shaders in user code.
A shader in its most common usage is a small program that is run by the GPU per-vertex in a mesh (a vertex shader) or per-affected-screen-fragment (a fragment shader.) The GPU executes these programs in a highly parallel way.
There are also compute shaders which are used for more general processing leveraging the GPU's parallelism.
"""
Mesh vertex buffer layouts (#3959) This PR makes a number of changes to how meshes and vertex attributes are handled, which the goal of enabling easy and flexible custom vertex attributes: * Reworks the `Mesh` type to use the newly added `VertexAttribute` internally * `VertexAttribute` defines the name, a unique `VertexAttributeId`, and a `VertexFormat` * `VertexAttributeId` is used to produce consistent sort orders for vertex buffer generation, replacing the more expensive and often surprising "name based sorting" * Meshes can be used to generate a `MeshVertexBufferLayout`, which defines the layout of the gpu buffer produced by the mesh. `MeshVertexBufferLayouts` can then be used to generate actual `VertexBufferLayouts` according to the requirements of a specific pipeline. This decoupling of "mesh layout" vs "pipeline vertex buffer layout" is what enables custom attributes. We don't need to standardize _mesh layouts_ or contort meshes to meet the needs of a specific pipeline. As long as the mesh has what the pipeline needs, it will work transparently. * Mesh-based pipelines now specialize on `&MeshVertexBufferLayout` via the new `SpecializedMeshPipeline` trait (which behaves like `SpecializedPipeline`, but adds `&MeshVertexBufferLayout`). The integrity of the pipeline cache is maintained because the `MeshVertexBufferLayout` is treated as part of the key (which is fully abstracted from implementers of the trait ... no need to add any additional info to the specialization key). * Hashing `MeshVertexBufferLayout` is too expensive to do for every entity, every frame. To make this scalable, I added a generalized "pre-hashing" solution to `bevy_utils`: `Hashed<T>` keys and `PreHashMap<K, V>` (which uses `Hashed<T>` internally) . Why didn't I just do the quick and dirty in-place "pre-compute hash and use that u64 as a key in a hashmap" that we've done in the past? Because its wrong! Hashes by themselves aren't enough because two different values can produce the same hash. Re-hashing a hash is even worse! I decided to build a generalized solution because this pattern has come up in the past and we've chosen to do the wrong thing. Now we can do the right thing! This did unfortunately require pulling in `hashbrown` and using that in `bevy_utils`, because avoiding re-hashes requires the `raw_entry_mut` api, which isn't stabilized yet (and may never be ... `entry_ref` has favor now, but also isn't available yet). If std's HashMap ever provides the tools we need, we can move back to that. Note that adding `hashbrown` doesn't increase our dependency count because it was already in our tree. I will probably break these changes out into their own PR. * Specializing on `MeshVertexBufferLayout` has one non-obvious behavior: it can produce identical pipelines for two different MeshVertexBufferLayouts. To optimize the number of active pipelines / reduce re-binds while drawing, I de-duplicate pipelines post-specialization using the final `VertexBufferLayout` as the key. For example, consider a pipeline that needs the layout `(position, normal)` and is specialized using two meshes: `(position, normal, uv)` and `(position, normal, other_vec2)`. If both of these meshes result in `(position, normal)` specializations, we can use the same pipeline! Now we do. Cool! To briefly illustrate, this is what the relevant section of `MeshPipeline`'s specialization code looks like now: ```rust impl SpecializedMeshPipeline for MeshPipeline { type Key = MeshPipelineKey; fn specialize( &self, key: Self::Key, layout: &MeshVertexBufferLayout, ) -> RenderPipelineDescriptor { let mut vertex_attributes = vec![ Mesh::ATTRIBUTE_POSITION.at_shader_location(0), Mesh::ATTRIBUTE_NORMAL.at_shader_location(1), Mesh::ATTRIBUTE_UV_0.at_shader_location(2), ]; let mut shader_defs = Vec::new(); if layout.contains(Mesh::ATTRIBUTE_TANGENT) { shader_defs.push(String::from("VERTEX_TANGENTS")); vertex_attributes.push(Mesh::ATTRIBUTE_TANGENT.at_shader_location(3)); } let vertex_buffer_layout = layout .get_layout(&vertex_attributes) .expect("Mesh is missing a vertex attribute"); ``` Notice that this is _much_ simpler than it was before. And now any mesh with any layout can be used with this pipeline, provided it has vertex postions, normals, and uvs. We even got to remove `HAS_TANGENTS` from MeshPipelineKey and `has_tangents` from `GpuMesh`, because that information is redundant with `MeshVertexBufferLayout`. This is still a draft because I still need to: * Add more docs * Experiment with adding error handling to mesh pipeline specialization (which would print errors at runtime when a mesh is missing a vertex attribute required by a pipeline). If it doesn't tank perf, we'll keep it. * Consider breaking out the PreHash / hashbrown changes into a separate PR. * Add an example illustrating this change * Verify that the "mesh-specialized pipeline de-duplication code" works properly Please dont yell at me for not doing these things yet :) Just trying to get this in peoples' hands asap. Alternative to #3120 Fixes #3030 Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-02-23 23:21:13 +00:00
[[example]]
name = "custom_vertex_attribute"
path = "examples/shader/custom_vertex_attribute.rs"
doc-scrape-examples = true
Mesh vertex buffer layouts (#3959) This PR makes a number of changes to how meshes and vertex attributes are handled, which the goal of enabling easy and flexible custom vertex attributes: * Reworks the `Mesh` type to use the newly added `VertexAttribute` internally * `VertexAttribute` defines the name, a unique `VertexAttributeId`, and a `VertexFormat` * `VertexAttributeId` is used to produce consistent sort orders for vertex buffer generation, replacing the more expensive and often surprising "name based sorting" * Meshes can be used to generate a `MeshVertexBufferLayout`, which defines the layout of the gpu buffer produced by the mesh. `MeshVertexBufferLayouts` can then be used to generate actual `VertexBufferLayouts` according to the requirements of a specific pipeline. This decoupling of "mesh layout" vs "pipeline vertex buffer layout" is what enables custom attributes. We don't need to standardize _mesh layouts_ or contort meshes to meet the needs of a specific pipeline. As long as the mesh has what the pipeline needs, it will work transparently. * Mesh-based pipelines now specialize on `&MeshVertexBufferLayout` via the new `SpecializedMeshPipeline` trait (which behaves like `SpecializedPipeline`, but adds `&MeshVertexBufferLayout`). The integrity of the pipeline cache is maintained because the `MeshVertexBufferLayout` is treated as part of the key (which is fully abstracted from implementers of the trait ... no need to add any additional info to the specialization key). * Hashing `MeshVertexBufferLayout` is too expensive to do for every entity, every frame. To make this scalable, I added a generalized "pre-hashing" solution to `bevy_utils`: `Hashed<T>` keys and `PreHashMap<K, V>` (which uses `Hashed<T>` internally) . Why didn't I just do the quick and dirty in-place "pre-compute hash and use that u64 as a key in a hashmap" that we've done in the past? Because its wrong! Hashes by themselves aren't enough because two different values can produce the same hash. Re-hashing a hash is even worse! I decided to build a generalized solution because this pattern has come up in the past and we've chosen to do the wrong thing. Now we can do the right thing! This did unfortunately require pulling in `hashbrown` and using that in `bevy_utils`, because avoiding re-hashes requires the `raw_entry_mut` api, which isn't stabilized yet (and may never be ... `entry_ref` has favor now, but also isn't available yet). If std's HashMap ever provides the tools we need, we can move back to that. Note that adding `hashbrown` doesn't increase our dependency count because it was already in our tree. I will probably break these changes out into their own PR. * Specializing on `MeshVertexBufferLayout` has one non-obvious behavior: it can produce identical pipelines for two different MeshVertexBufferLayouts. To optimize the number of active pipelines / reduce re-binds while drawing, I de-duplicate pipelines post-specialization using the final `VertexBufferLayout` as the key. For example, consider a pipeline that needs the layout `(position, normal)` and is specialized using two meshes: `(position, normal, uv)` and `(position, normal, other_vec2)`. If both of these meshes result in `(position, normal)` specializations, we can use the same pipeline! Now we do. Cool! To briefly illustrate, this is what the relevant section of `MeshPipeline`'s specialization code looks like now: ```rust impl SpecializedMeshPipeline for MeshPipeline { type Key = MeshPipelineKey; fn specialize( &self, key: Self::Key, layout: &MeshVertexBufferLayout, ) -> RenderPipelineDescriptor { let mut vertex_attributes = vec![ Mesh::ATTRIBUTE_POSITION.at_shader_location(0), Mesh::ATTRIBUTE_NORMAL.at_shader_location(1), Mesh::ATTRIBUTE_UV_0.at_shader_location(2), ]; let mut shader_defs = Vec::new(); if layout.contains(Mesh::ATTRIBUTE_TANGENT) { shader_defs.push(String::from("VERTEX_TANGENTS")); vertex_attributes.push(Mesh::ATTRIBUTE_TANGENT.at_shader_location(3)); } let vertex_buffer_layout = layout .get_layout(&vertex_attributes) .expect("Mesh is missing a vertex attribute"); ``` Notice that this is _much_ simpler than it was before. And now any mesh with any layout can be used with this pipeline, provided it has vertex postions, normals, and uvs. We even got to remove `HAS_TANGENTS` from MeshPipelineKey and `has_tangents` from `GpuMesh`, because that information is redundant with `MeshVertexBufferLayout`. This is still a draft because I still need to: * Add more docs * Experiment with adding error handling to mesh pipeline specialization (which would print errors at runtime when a mesh is missing a vertex attribute required by a pipeline). If it doesn't tank perf, we'll keep it. * Consider breaking out the PreHash / hashbrown changes into a separate PR. * Add an example illustrating this change * Verify that the "mesh-specialized pipeline de-duplication code" works properly Please dont yell at me for not doing these things yet :) Just trying to get this in peoples' hands asap. Alternative to #3120 Fixes #3030 Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-02-23 23:21:13 +00:00
[package.metadata.example.custom_vertex_attribute]
name = "Custom Vertex Attribute"
description = "A shader that reads a mesh's custom vertex attribute"
category = "Shaders"
wasm = true
[[example]]
name = "post_processing"
path = "examples/shader/post_processing.rs"
doc-scrape-examples = true
[package.metadata.example.post_processing]
name = "Post Processing - Custom Render Pass"
description = "A custom post processing effect, using a custom render pass that runs after the main pass"
category = "Shaders"
wasm = true
2020-05-01 20:12:47 +00:00
[[example]]
name = "shader_defs"
path = "examples/shader/shader_defs.rs"
doc-scrape-examples = true
2020-05-01 20:12:47 +00:00
[package.metadata.example.shader_defs]
name = "Shader Defs"
description = "A shader that uses \"shaders defs\" (a bevy tool to selectively toggle parts of a shader)"
category = "Shaders"
wasm = true
Modular Rendering (#2831) This changes how render logic is composed to make it much more modular. Previously, all extraction logic was centralized for a given "type" of rendered thing. For example, we extracted meshes into a vector of ExtractedMesh, which contained the mesh and material asset handles, the transform, etc. We looked up bindings for "drawn things" using their index in the `Vec<ExtractedMesh>`. This worked fine for built in rendering, but made it hard to reuse logic for "custom" rendering. It also prevented us from reusing things like "extracted transforms" across contexts. To make rendering more modular, I made a number of changes: * Entities now drive rendering: * We extract "render components" from "app components" and store them _on_ entities. No more centralized uber lists! We now have true "ECS-driven rendering" * To make this perform well, I implemented #2673 in upstream Bevy for fast batch insertions into specific entities. This was merged into the `pipelined-rendering` branch here: #2815 * Reworked the `Draw` abstraction: * Generic `PhaseItems`: each draw phase can define its own type of "rendered thing", which can define its own "sort key" * Ported the 2d, 3d, and shadow phases to the new PhaseItem impl (currently Transparent2d, Transparent3d, and Shadow PhaseItems) * `Draw` trait and and `DrawFunctions` are now generic on PhaseItem * Modular / Ergonomic `DrawFunctions` via `RenderCommands` * RenderCommand is a trait that runs an ECS query and produces one or more RenderPass calls. Types implementing this trait can be composed to create a final DrawFunction. For example the DrawPbr DrawFunction is created from the following DrawCommand tuple. Const generics are used to set specific bind group locations: ```rust pub type DrawPbr = ( SetPbrPipeline, SetMeshViewBindGroup<0>, SetStandardMaterialBindGroup<1>, SetTransformBindGroup<2>, DrawMesh, ); ``` * The new `custom_shader_pipelined` example illustrates how the commands above can be reused to create a custom draw function: ```rust type DrawCustom = ( SetCustomMaterialPipeline, SetMeshViewBindGroup<0>, SetTransformBindGroup<2>, DrawMesh, ); ``` * ExtractComponentPlugin and UniformComponentPlugin: * Simple, standardized ways to easily extract individual components and write them to GPU buffers * Ported PBR and Sprite rendering to the new primitives above. * Removed staging buffer from UniformVec in favor of direct Queue usage * Makes UniformVec much easier to use and more ergonomic. Completely removes the need for custom render graph nodes in these contexts (see the PbrNode and view Node removals and the much simpler call patterns in the relevant Prepare systems). * Added a many_cubes_pipelined example to benchmark baseline 3d rendering performance and ensure there were no major regressions during this port. Avoiding regressions was challenging given that the old approach of extracting into centralized vectors is basically the "optimal" approach. However thanks to a various ECS optimizations and render logic rephrasing, we pretty much break even on this benchmark! * Lifetimeless SystemParams: this will be a bit divisive, but as we continue to embrace "trait driven systems" (ex: ExtractComponentPlugin, UniformComponentPlugin, DrawCommand), the ergonomics of `(Query<'static, 'static, (&'static A, &'static B, &'static)>, Res<'static, C>)` were getting very hard to bear. As a compromise, I added "static type aliases" for the relevant SystemParams. The previous example can now be expressed like this: `(SQuery<(Read<A>, Read<B>)>, SRes<C>)`. If anyone has better ideas / conflicting opinions, please let me know! * RunSystem trait: a way to define Systems via a trait with a SystemParam associated type. This is used to implement the various plugins mentioned above. I also added SystemParamItem and QueryItem type aliases to make "trait stye" ecs interactions nicer on the eyes (and fingers). * RenderAsset retrying: ensures that render assets are only created when they are "ready" and allows us to create bind groups directly inside render assets (which significantly simplified the StandardMaterial code). I think ultimately we should swap this out on "asset dependency" events to wait for dependencies to load, but this will require significant asset system changes. * Updated some built in shaders to account for missing MeshUniform fields
2021-09-23 06:16:11 +00:00
[[example]]
name = "shader_material"
path = "examples/shader/shader_material.rs"
doc-scrape-examples = true
Pipeline Specialization, Shader Assets, and Shader Preprocessing (#3031) ## New Features This adds the following to the new renderer: * **Shader Assets** * Shaders are assets again! Users no longer need to call `include_str!` for their shaders * Shader hot-reloading * **Shader Defs / Shader Preprocessing** * Shaders now support `# ifdef NAME`, `# ifndef NAME`, and `# endif` preprocessor directives * **Bevy RenderPipelineDescriptor and RenderPipelineCache** * Bevy now provides its own `RenderPipelineDescriptor` and the wgpu version is now exported as `RawRenderPipelineDescriptor`. This allows users to define pipelines with `Handle<Shader>` instead of needing to manually compile and reference `ShaderModules`, enables passing in shader defs to configure the shader preprocessor, makes hot reloading possible (because the descriptor can be owned and used to create new pipelines when a shader changes), and opens the doors to pipeline specialization. * The `RenderPipelineCache` now handles compiling and re-compiling Bevy RenderPipelineDescriptors. It has internal PipelineLayout and ShaderModule caches. Users receive a `CachedPipelineId`, which can be used to look up the actual `&RenderPipeline` during rendering. * **Pipeline Specialization** * This enables defining per-entity-configurable pipelines that specialize on arbitrary custom keys. In practice this will involve specializing based on things like MSAA values, Shader Defs, Bind Group existence, and Vertex Layouts. * Adds a `SpecializedPipeline` trait and `SpecializedPipelines<MyPipeline>` resource. This is a simple layer that generates Bevy RenderPipelineDescriptors based on a custom key defined for the pipeline. * Specialized pipelines are also hot-reloadable. * This was the result of experimentation with two different approaches: 1. **"generic immediate mode multi-key hash pipeline specialization"** * breaks up the pipeline into multiple "identities" (the core pipeline definition, shader defs, mesh layout, bind group layout). each of these identities has its own key. looking up / compiling a specific version of a pipeline requires composing all of these keys together * the benefit of this approach is that it works for all pipelines / the pipeline is fully identified by the keys. the multiple keys allow pre-hashing parts of the pipeline identity where possible (ex: pre compute the mesh identity for all meshes) * the downside is that any per-entity data that informs the values of these keys could require expensive re-hashes. computing each key for each sprite tanked bevymark performance (sprites don't actually need this level of specialization yet ... but things like pbr and future sprite scenarios might). * this is the approach rafx used last time i checked 2. **"custom key specialization"** * Pipelines by default are not specialized * Pipelines that need specialization implement a SpecializedPipeline trait with a custom key associated type * This allows specialization keys to encode exactly the amount of information required (instead of needing to be a combined hash of the entire pipeline). Generally this should fit in a small number of bytes. Per-entity specialization barely registers anymore on things like bevymark. It also makes things like "shader defs" way cheaper to hash because we can use context specific bitflags instead of strings. * Despite the extra trait, it actually generally makes pipeline definitions + lookups simpler: managing multiple keys (and making the appropriate calls to manage these keys) was way more complicated. * I opted for custom key specialization. It performs better generally and in my opinion is better UX. Fortunately the way this is implemented also allows for custom caches as this all builds on a common abstraction: the RenderPipelineCache. The built in custom key trait is just a simple / pre-defined way to interact with the cache ## Callouts * The SpecializedPipeline trait makes it easy to inherit pipeline configuration in custom pipelines. The changes to `custom_shader_pipelined` and the new `shader_defs_pipelined` example illustrate how much simpler it is to define custom pipelines based on the PbrPipeline. * The shader preprocessor is currently pretty naive (it just uses regexes to process each line). Ultimately we might want to build a more custom parser for more performance + better error handling, but for now I'm happy to optimize for "easy to implement and understand". ## Next Steps * Port compute pipelines to the new system * Add more preprocessor directives (else, elif, import) * More flexible vertex attribute specialization / enable cheaply specializing on specific mesh vertex layouts
2021-10-28 19:07:47 +00:00
[package.metadata.example.shader_material]
name = "Material"
description = "A shader and a material that uses it"
category = "Shaders"
wasm = true
[[example]]
name = "extended_material"
path = "examples/shader/extended_material.rs"
[package.metadata.example.extended_material]
name = "Extended Material"
description = "A custom shader that builds on the standard material"
category = "Shaders"
wasm = true
Add depth and normal prepass (#6284) # Objective - Add a configurable prepass - A depth prepass is useful for various shader effects and to reduce overdraw. It can be expansive depending on the scene so it's important to be able to disable it if you don't need any effects that uses it or don't suffer from excessive overdraw. - The goal is to eventually use it for things like TAA, Ambient Occlusion, SSR and various other techniques that can benefit from having a prepass. ## Solution The prepass node is inserted before the main pass. It runs for each `Camera3d` with a prepass component (`DepthPrepass`, `NormalPrepass`). The presence of one of those components is used to determine which textures are generated in the prepass. When any prepass is enabled, the depth buffer generated will be used by the main pass to reduce overdraw. The prepass runs for each `Material` created with the `MaterialPlugin::prepass_enabled` option set to `true`. You can overload the shader used by the prepass by using `Material::prepass_vertex_shader()` and/or `Material::prepass_fragment_shader()`. It will also use the `Material::specialize()` for more advanced use cases. It is enabled by default on all materials. The prepass works on opaque materials and materials using an alpha mask. Transparent materials are ignored. The `StandardMaterial` overloads the prepass fragment shader to support alpha mask and normal maps. --- ## Changelog - Add a new `PrepassNode` that runs before the main pass - Add a `PrepassPlugin` to extract/prepare/queue the necessary data - Add a `DepthPrepass` and `NormalPrepass` component to control which textures will be created by the prepass and available in later passes. - Add a new `prepass_enabled` flag to the `MaterialPlugin` that will control if a material uses the prepass or not. - Add a new `prepass_enabled` flag to the `PbrPlugin` to control if the StandardMaterial uses the prepass. Currently defaults to false. - Add `Material::prepass_vertex_shader()` and `Material::prepass_fragment_shader()` to control the prepass from the `Material` ## Notes In bevy's sample 3d scene, the performance is actually worse when enabling the prepass, but on more complex scenes the performance is generally better. I would like more testing on this, but @DGriffin91 has reported a very noticeable improvements in some scenes. The prepass is also used by @JMS55 for TAA and GTAO discord thread: <https://discord.com/channels/691052431525675048/1011624228627419187> This PR was built on top of the work of multiple people Co-Authored-By: @superdump Co-Authored-By: @robtfm Co-Authored-By: @JMS55 Co-authored-by: Charles <IceSentry@users.noreply.github.com> Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
2023-01-19 22:11:13 +00:00
[[example]]
name = "shader_prepass"
path = "examples/shader/shader_prepass.rs"
doc-scrape-examples = true
Add depth and normal prepass (#6284) # Objective - Add a configurable prepass - A depth prepass is useful for various shader effects and to reduce overdraw. It can be expansive depending on the scene so it's important to be able to disable it if you don't need any effects that uses it or don't suffer from excessive overdraw. - The goal is to eventually use it for things like TAA, Ambient Occlusion, SSR and various other techniques that can benefit from having a prepass. ## Solution The prepass node is inserted before the main pass. It runs for each `Camera3d` with a prepass component (`DepthPrepass`, `NormalPrepass`). The presence of one of those components is used to determine which textures are generated in the prepass. When any prepass is enabled, the depth buffer generated will be used by the main pass to reduce overdraw. The prepass runs for each `Material` created with the `MaterialPlugin::prepass_enabled` option set to `true`. You can overload the shader used by the prepass by using `Material::prepass_vertex_shader()` and/or `Material::prepass_fragment_shader()`. It will also use the `Material::specialize()` for more advanced use cases. It is enabled by default on all materials. The prepass works on opaque materials and materials using an alpha mask. Transparent materials are ignored. The `StandardMaterial` overloads the prepass fragment shader to support alpha mask and normal maps. --- ## Changelog - Add a new `PrepassNode` that runs before the main pass - Add a `PrepassPlugin` to extract/prepare/queue the necessary data - Add a `DepthPrepass` and `NormalPrepass` component to control which textures will be created by the prepass and available in later passes. - Add a new `prepass_enabled` flag to the `MaterialPlugin` that will control if a material uses the prepass or not. - Add a new `prepass_enabled` flag to the `PbrPlugin` to control if the StandardMaterial uses the prepass. Currently defaults to false. - Add `Material::prepass_vertex_shader()` and `Material::prepass_fragment_shader()` to control the prepass from the `Material` ## Notes In bevy's sample 3d scene, the performance is actually worse when enabling the prepass, but on more complex scenes the performance is generally better. I would like more testing on this, but @DGriffin91 has reported a very noticeable improvements in some scenes. The prepass is also used by @JMS55 for TAA and GTAO discord thread: <https://discord.com/channels/691052431525675048/1011624228627419187> This PR was built on top of the work of multiple people Co-Authored-By: @superdump Co-Authored-By: @robtfm Co-Authored-By: @JMS55 Co-authored-by: Charles <IceSentry@users.noreply.github.com> Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
2023-01-19 22:11:13 +00:00
[package.metadata.example.shader_prepass]
name = "Material Prepass"
description = "A shader that uses the various textures generated by the prepass"
Add depth and normal prepass (#6284) # Objective - Add a configurable prepass - A depth prepass is useful for various shader effects and to reduce overdraw. It can be expansive depending on the scene so it's important to be able to disable it if you don't need any effects that uses it or don't suffer from excessive overdraw. - The goal is to eventually use it for things like TAA, Ambient Occlusion, SSR and various other techniques that can benefit from having a prepass. ## Solution The prepass node is inserted before the main pass. It runs for each `Camera3d` with a prepass component (`DepthPrepass`, `NormalPrepass`). The presence of one of those components is used to determine which textures are generated in the prepass. When any prepass is enabled, the depth buffer generated will be used by the main pass to reduce overdraw. The prepass runs for each `Material` created with the `MaterialPlugin::prepass_enabled` option set to `true`. You can overload the shader used by the prepass by using `Material::prepass_vertex_shader()` and/or `Material::prepass_fragment_shader()`. It will also use the `Material::specialize()` for more advanced use cases. It is enabled by default on all materials. The prepass works on opaque materials and materials using an alpha mask. Transparent materials are ignored. The `StandardMaterial` overloads the prepass fragment shader to support alpha mask and normal maps. --- ## Changelog - Add a new `PrepassNode` that runs before the main pass - Add a `PrepassPlugin` to extract/prepare/queue the necessary data - Add a `DepthPrepass` and `NormalPrepass` component to control which textures will be created by the prepass and available in later passes. - Add a new `prepass_enabled` flag to the `MaterialPlugin` that will control if a material uses the prepass or not. - Add a new `prepass_enabled` flag to the `PbrPlugin` to control if the StandardMaterial uses the prepass. Currently defaults to false. - Add `Material::prepass_vertex_shader()` and `Material::prepass_fragment_shader()` to control the prepass from the `Material` ## Notes In bevy's sample 3d scene, the performance is actually worse when enabling the prepass, but on more complex scenes the performance is generally better. I would like more testing on this, but @DGriffin91 has reported a very noticeable improvements in some scenes. The prepass is also used by @JMS55 for TAA and GTAO discord thread: <https://discord.com/channels/691052431525675048/1011624228627419187> This PR was built on top of the work of multiple people Co-Authored-By: @superdump Co-Authored-By: @robtfm Co-Authored-By: @JMS55 Co-authored-by: Charles <IceSentry@users.noreply.github.com> Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
2023-01-19 22:11:13 +00:00
category = "Shaders"
wasm = false
[[example]]
name = "shader_material_screenspace_texture"
path = "examples/shader/shader_material_screenspace_texture.rs"
doc-scrape-examples = true
[package.metadata.example.shader_material_screenspace_texture]
name = "Material - Screenspace Texture"
description = "A shader that samples a texture with view-independent UV coordinates"
category = "Shaders"
wasm = true
[[example]]
name = "shader_material_glsl"
path = "examples/shader/shader_material_glsl.rs"
doc-scrape-examples = true
[package.metadata.example.shader_material_glsl]
name = "Material - GLSL"
description = "A shader that uses the GLSL shading language"
category = "Shaders"
wasm = true
[[example]]
name = "shader_instancing"
path = "examples/shader/shader_instancing.rs"
doc-scrape-examples = true
[package.metadata.example.shader_instancing]
name = "Instancing"
description = "A shader that renders a mesh multiple times in one draw call"
category = "Shaders"
wasm = true
[[example]]
name = "animate_shader"
path = "examples/shader/animate_shader.rs"
doc-scrape-examples = true
[package.metadata.example.animate_shader]
name = "Animated"
description = "A shader that uses dynamic data like the time since startup"
category = "Shaders"
wasm = true
[[example]]
name = "compute_shader_game_of_life"
path = "examples/shader/compute_shader_game_of_life.rs"
doc-scrape-examples = true
[package.metadata.example.compute_shader_game_of_life]
name = "Compute - Game of Life"
description = "A compute shader that simulates Conway's Game of Life"
category = "Shaders"
wasm = false
[[example]]
name = "array_texture"
path = "examples/shader/array_texture.rs"
doc-scrape-examples = true
[package.metadata.example.array_texture]
name = "Array Texture"
description = "A shader that shows how to reuse the core bevy PBR shading functionality in a custom material that obtains the base color from an array texture."
category = "Shaders"
wasm = true
[[example]]
name = "texture_binding_array"
path = "examples/shader/texture_binding_array.rs"
doc-scrape-examples = true
[package.metadata.example.texture_binding_array]
name = "Texture Binding Array (Bindless Textures)"
description = "A shader that shows how to bind and sample multiple textures as a binding array (a.k.a. bindless textures)."
category = "Shaders"
wasm = false
# Stress tests
[[package.metadata.example_category]]
name = "Stress Tests"
description = """
These examples are used to test the performance and stability of various parts of the engine in an isolated way.
Due to the focus on performance it's recommended to run the stress tests in release mode:
```sh
cargo run --release --example <example name>
```
"""
[[example]]
name = "bevymark"
path = "examples/stress_tests/bevymark.rs"
doc-scrape-examples = true
[package.metadata.example.bevymark]
name = "Bevymark"
description = "A heavy sprite rendering workload to benchmark your system with Bevy"
category = "Stress Tests"
wasm = true
[[example]]
name = "many_animated_sprites"
path = "examples/stress_tests/many_animated_sprites.rs"
doc-scrape-examples = true
[package.metadata.example.many_animated_sprites]
name = "Many Animated Sprites"
description = "Displays many animated sprites in a grid arrangement with slight offsets to their animation timers. Used for performance testing."
category = "Stress Tests"
wasm = true
[[example]]
name = "many_buttons"
path = "examples/stress_tests/many_buttons.rs"
doc-scrape-examples = true
[package.metadata.example.many_buttons]
name = "Many Buttons"
description = "Test rendering of many UI elements"
category = "Stress Tests"
wasm = true
[[example]]
name = "many_cubes"
path = "examples/stress_tests/many_cubes.rs"
doc-scrape-examples = true
[package.metadata.example.many_cubes]
name = "Many Cubes"
description = "Simple benchmark to test per-entity draw overhead. Run with the `sphere` argument to test frustum culling"
category = "Stress Tests"
wasm = true
Immediate Mode Line/Gizmo Drawing (#6529) # Objective Add a convenient immediate mode drawing API for visual debugging. Fixes #5619 Alternative to #1625 Partial alternative to #5734 Based off https://github.com/Toqozz/bevy_debug_lines with some changes: * Simultaneous support for 2D and 3D. * Methods for basic shapes; circles, spheres, rectangles, boxes, etc. * 2D methods. * Removed durations. Seemed niche, and can be handled by users. <details> <summary>Performance</summary> Stress tested using Bevy's recommended optimization settings for the dev profile with the following command. ```bash cargo run --example many_debug_lines \ --config "profile.dev.package.\"*\".opt-level=3" \ --config "profile.dev.opt-level=1" ``` I dipped to 65-70 FPS at 300,000 lines CPU: 3700x RAM Speed: 3200 Mhz GPU: 2070 super - probably not very relevant, mostly cpu/memory bound </details> <details> <summary>Fancy bloom screenshot</summary> ![Screenshot_20230207_155033](https://user-images.githubusercontent.com/29694403/217291980-f1e0500e-7a14-4131-8c96-eaaaf52596ae.png) </details> ## Changelog * Added `GizmoPlugin` * Added `Gizmos` system parameter for drawing lines and wireshapes. ### TODO - [ ] Update changelog - [x] Update performance numbers - [x] Add credit to PR description ### Future work - Cache rendering primitives instead of constructing them out of line segments each frame. - Support for drawing solid meshes - Interactions. (See [bevy_mod_gizmos](https://github.com/LiamGallagher737/bevy_mod_gizmos)) - Fancier line drawing. (See [bevy_polyline](https://github.com/ForesightMiningSoftwareCorporation/bevy_polyline)) - Support for `RenderLayers` - Display gizmos for a certain duration. Currently everything displays for one frame (ie. immediate mode) - Changing settings per drawn item like drawing on top or drawing to different `RenderLayers` Co-Authored By: @lassade <felipe.jorge.pereira@gmail.com> Co-Authored By: @The5-1 <agaku@hotmail.de> Co-Authored By: @Toqozz <toqoz@hotmail.com> Co-Authored By: @nicopap <nico@nicopap.ch> --------- Co-authored-by: Robert Swain <robert.swain@gmail.com> Co-authored-by: IceSentry <c.giguere42@gmail.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2023-03-20 20:57:54 +00:00
[[example]]
name = "many_gizmos"
path = "examples/stress_tests/many_gizmos.rs"
doc-scrape-examples = true
Immediate Mode Line/Gizmo Drawing (#6529) # Objective Add a convenient immediate mode drawing API for visual debugging. Fixes #5619 Alternative to #1625 Partial alternative to #5734 Based off https://github.com/Toqozz/bevy_debug_lines with some changes: * Simultaneous support for 2D and 3D. * Methods for basic shapes; circles, spheres, rectangles, boxes, etc. * 2D methods. * Removed durations. Seemed niche, and can be handled by users. <details> <summary>Performance</summary> Stress tested using Bevy's recommended optimization settings for the dev profile with the following command. ```bash cargo run --example many_debug_lines \ --config "profile.dev.package.\"*\".opt-level=3" \ --config "profile.dev.opt-level=1" ``` I dipped to 65-70 FPS at 300,000 lines CPU: 3700x RAM Speed: 3200 Mhz GPU: 2070 super - probably not very relevant, mostly cpu/memory bound </details> <details> <summary>Fancy bloom screenshot</summary> ![Screenshot_20230207_155033](https://user-images.githubusercontent.com/29694403/217291980-f1e0500e-7a14-4131-8c96-eaaaf52596ae.png) </details> ## Changelog * Added `GizmoPlugin` * Added `Gizmos` system parameter for drawing lines and wireshapes. ### TODO - [ ] Update changelog - [x] Update performance numbers - [x] Add credit to PR description ### Future work - Cache rendering primitives instead of constructing them out of line segments each frame. - Support for drawing solid meshes - Interactions. (See [bevy_mod_gizmos](https://github.com/LiamGallagher737/bevy_mod_gizmos)) - Fancier line drawing. (See [bevy_polyline](https://github.com/ForesightMiningSoftwareCorporation/bevy_polyline)) - Support for `RenderLayers` - Display gizmos for a certain duration. Currently everything displays for one frame (ie. immediate mode) - Changing settings per drawn item like drawing on top or drawing to different `RenderLayers` Co-Authored By: @lassade <felipe.jorge.pereira@gmail.com> Co-Authored By: @The5-1 <agaku@hotmail.de> Co-Authored By: @Toqozz <toqoz@hotmail.com> Co-Authored By: @nicopap <nico@nicopap.ch> --------- Co-authored-by: Robert Swain <robert.swain@gmail.com> Co-authored-by: IceSentry <c.giguere42@gmail.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2023-03-20 20:57:54 +00:00
[package.metadata.example.many_gizmos]
name = "Many Gizmos"
description = "Test rendering of many gizmos"
category = "Stress Tests"
wasm = true
[[example]]
name = "many_foxes"
path = "examples/stress_tests/many_foxes.rs"
doc-scrape-examples = true
[package.metadata.example.many_foxes]
name = "Many Foxes"
description = "Loads an animated fox model and spawns lots of them. Good for testing skinned mesh performance. Takes an unsigned integer argument for the number of foxes to spawn. Defaults to 1000"
category = "Stress Tests"
wasm = true
[[example]]
name = "many_glyphs"
path = "examples/stress_tests/many_glyphs.rs"
doc-scrape-examples = true
[package.metadata.example.many_glyphs]
name = "Many Glyphs"
description = "Simple benchmark to test text rendering."
category = "Stress Tests"
wasm = true
[[example]]
name = "many_lights"
path = "examples/stress_tests/many_lights.rs"
doc-scrape-examples = true
[package.metadata.example.many_lights]
name = "Many Lights"
description = "Simple benchmark to test rendering many point lights. Run with `WGPU_SETTINGS_PRIO=webgl2` to restrict to uniform buffers and max 256 lights"
category = "Stress Tests"
wasm = true
[[example]]
name = "many_sprites"
path = "examples/stress_tests/many_sprites.rs"
doc-scrape-examples = true
[package.metadata.example.many_sprites]
name = "Many Sprites"
description = "Displays many sprites in a grid arrangement! Used for performance testing. Use `--colored` to enable color tinted sprites."
category = "Stress Tests"
wasm = true
[[example]]
name = "transform_hierarchy"
path = "examples/stress_tests/transform_hierarchy.rs"
doc-scrape-examples = true
[package.metadata.example.transform_hierarchy]
name = "Transform Hierarchy"
description = "Various test cases for hierarchy and transform propagation performance"
category = "Stress Tests"
wasm = false
[[example]]
name = "text_pipeline"
path = "examples/stress_tests/text_pipeline.rs"
doc-scrape-examples = true
[package.metadata.example.text_pipeline]
name = "Text Pipeline"
description = "Text Pipeline benchmark"
category = "Stress Tests"
wasm = false
# Tools
[[example]]
name = "scene_viewer"
path = "examples/tools/scene_viewer/main.rs"
doc-scrape-examples = true
[package.metadata.example.scene_viewer]
name = "Scene Viewer"
description = "A simple way to view glTF models with Bevy. Just run `cargo run --release --example scene_viewer /path/to/model.gltf#Scene0`, replacing the path as appropriate. With no arguments it will load the FieldHelmet glTF model from the repository assets subdirectory"
category = "Tools"
wasm = true
[[example]]
name = "gamepad_viewer"
path = "examples/tools/gamepad_viewer.rs"
doc-scrape-examples = true
[package.metadata.example.gamepad_viewer]
name = "Gamepad Viewer"
description = "Shows a visualization of gamepad buttons, sticks, and triggers"
category = "Tools"
wasm = true
Reduce internal system order ambiguities, and add an example explaining them (#7383) # Objective - Bevy should not have any "internal" execution order ambiguities. These clutter the output of user-facing error reporting, and can result in nasty, nondetermistic, very difficult to solve bugs. - Verifying this currently involves repeated non-trivial manual work. ## Solution - [x] add an example to quickly check this - ~~[ ] ensure that this example panics if there are any unresolved ambiguities~~ - ~~[ ] run the example in CI :smiling_imp:~~ There's one tricky ambiguity left, between UI and animation. I don't have the tools to fix this without system set configuration, so the remaining work is going to be left to #7267 or another PR after that. ``` 2023-01-27T18:38:42.989405Z INFO bevy_ecs::schedule::ambiguity_detection: Execution order ambiguities detected, you might want to add an explicit dependency relation between some of these systems: * Parallel systems: -- "bevy_animation::animation_player" and "bevy_ui::flex::flex_node_system" conflicts: ["bevy_transform::components::transform::Transform"] ``` ## Changelog Resolved internal execution order ambiguities for: 1. Transform propagation (ignored, we need smarter filter checking). 2. Gamepad processing (fixed). 3. bevy_winit's window handling (fixed). 4. Cascaded shadow maps and perspectives (fixed). Also fixed a desynchronized state bug that could occur when the `Window` component is removed and then added to the same entity in a single frame.
2023-01-31 01:47:00 +00:00
[[example]]
name = "nondeterministic_system_order"
path = "examples/ecs/nondeterministic_system_order.rs"
doc-scrape-examples = true
Reduce internal system order ambiguities, and add an example explaining them (#7383) # Objective - Bevy should not have any "internal" execution order ambiguities. These clutter the output of user-facing error reporting, and can result in nasty, nondetermistic, very difficult to solve bugs. - Verifying this currently involves repeated non-trivial manual work. ## Solution - [x] add an example to quickly check this - ~~[ ] ensure that this example panics if there are any unresolved ambiguities~~ - ~~[ ] run the example in CI :smiling_imp:~~ There's one tricky ambiguity left, between UI and animation. I don't have the tools to fix this without system set configuration, so the remaining work is going to be left to #7267 or another PR after that. ``` 2023-01-27T18:38:42.989405Z INFO bevy_ecs::schedule::ambiguity_detection: Execution order ambiguities detected, you might want to add an explicit dependency relation between some of these systems: * Parallel systems: -- "bevy_animation::animation_player" and "bevy_ui::flex::flex_node_system" conflicts: ["bevy_transform::components::transform::Transform"] ``` ## Changelog Resolved internal execution order ambiguities for: 1. Transform propagation (ignored, we need smarter filter checking). 2. Gamepad processing (fixed). 3. bevy_winit's window handling (fixed). 4. Cascaded shadow maps and perspectives (fixed). Also fixed a desynchronized state bug that could occur when the `Window` component is removed and then added to the same entity in a single frame.
2023-01-31 01:47:00 +00:00
[package.metadata.example.nondeterministic_system_order]
name = "Nondeterministic System Order"
description = "Systems run in parallel, but their order isn't always deterministic. Here's how to detect and fix this."
Reduce internal system order ambiguities, and add an example explaining them (#7383) # Objective - Bevy should not have any "internal" execution order ambiguities. These clutter the output of user-facing error reporting, and can result in nasty, nondetermistic, very difficult to solve bugs. - Verifying this currently involves repeated non-trivial manual work. ## Solution - [x] add an example to quickly check this - ~~[ ] ensure that this example panics if there are any unresolved ambiguities~~ - ~~[ ] run the example in CI :smiling_imp:~~ There's one tricky ambiguity left, between UI and animation. I don't have the tools to fix this without system set configuration, so the remaining work is going to be left to #7267 or another PR after that. ``` 2023-01-27T18:38:42.989405Z INFO bevy_ecs::schedule::ambiguity_detection: Execution order ambiguities detected, you might want to add an explicit dependency relation between some of these systems: * Parallel systems: -- "bevy_animation::animation_player" and "bevy_ui::flex::flex_node_system" conflicts: ["bevy_transform::components::transform::Transform"] ``` ## Changelog Resolved internal execution order ambiguities for: 1. Transform propagation (ignored, we need smarter filter checking). 2. Gamepad processing (fixed). 3. bevy_winit's window handling (fixed). 4. Cascaded shadow maps and perspectives (fixed). Also fixed a desynchronized state bug that could occur when the `Window` component is removed and then added to the same entity in a single frame.
2023-01-31 01:47:00 +00:00
category = "ECS (Entity Component System)"
wasm = false
[[example]]
name = "3d_rotation"
path = "examples/transforms/3d_rotation.rs"
doc-scrape-examples = true
[package.metadata.example.3d_rotation]
name = "3D Rotation"
description = "Illustrates how to (constantly) rotate an object around an axis"
category = "Transforms"
wasm = true
[[example]]
name = "scale"
path = "examples/transforms/scale.rs"
doc-scrape-examples = true
[package.metadata.example.scale]
name = "Scale"
description = "Illustrates how to scale an object in each direction"
category = "Transforms"
wasm = true
[[example]]
name = "transform"
path = "examples/transforms/transform.rs"
doc-scrape-examples = true
[package.metadata.example.transform]
name = "Transform"
description = "Shows multiple transformations of objects"
category = "Transforms"
wasm = true
[[example]]
name = "translation"
path = "examples/transforms/translation.rs"
doc-scrape-examples = true
[package.metadata.example.translation]
name = "Translation"
description = "Illustrates how to move an object along an axis"
category = "Transforms"
wasm = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
# UI (User Interface)
[[example]]
name = "borders"
path = "examples/ui/borders.rs"
doc-scrape-examples = true
[package.metadata.example.borders]
name = "Borders"
description = "Demonstrates how to create a node with a border"
category = "UI (User Interface)"
wasm = true
[[example]]
name = "button"
path = "examples/ui/button.rs"
doc-scrape-examples = true
[package.metadata.example.button]
name = "Button"
description = "Illustrates creating and updating a button"
category = "UI (User Interface)"
wasm = true
[[example]]
name = "display_and_visibility"
path = "examples/ui/display_and_visibility.rs"
doc-scrape-examples = true
[package.metadata.example.display_and_visibility]
name = "Display and Visibility"
description = "Demonstrates how Display and Visibility work in the UI."
category = "UI (User Interface)"
wasm = true
[[example]]
name = "window_fallthrough"
path = "examples/ui/window_fallthrough.rs"
doc-scrape-examples = true
[package.metadata.example.window_fallthrough]
name = "Window Fallthrough"
description = "Illustrates how to access `winit::window::Window`'s `hittest` functionality."
category = "UI (User Interface)"
wasm = false
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[[example]]
name = "font_atlas_debug"
path = "examples/ui/font_atlas_debug.rs"
doc-scrape-examples = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
[package.metadata.example.font_atlas_debug]
name = "Font Atlas Debug"
description = "Illustrates how FontAtlases are populated (used to optimize text rendering internally)"
category = "UI (User Interface)"
wasm = true
Split UI `Overflow` by axis (#8095) # Objective Split the UI overflow enum so that overflow can be set for each axis separately. ## Solution Change `Overflow` from an enum to a struct with `x` and `y` `OverflowAxis` fields, where `OverflowAxis` is an enum with `Clip` and `Visible` variants. Modify `update_clipping` to calculate clipping for each axis separately. If only one axis is clipped, the other axis is given infinite bounds. <img width="642" alt="overflow" src="https://user-images.githubusercontent.com/27962798/227592983-568cf76f-7e40-48c4-a511-43c886f5e431.PNG"> --- ## Changelog * Split the UI overflow implementation so overflow can be set for each axis separately. * Added the enum `OverflowAxis` with `Clip` and `Visible` variants. * Changed `Overflow` to a struct with `x` and `y` fields of type `OverflowAxis`. * `Overflow` has new methods `visible()` and `hidden()` that replace its previous `Clip` and `Visible` variants. * Added `Overflow` helper methods `clip_x()` and `clip_y()` that return a new `Overflow` value with the given axis clipped. * Modified `update_clipping` so it calculates clipping for each axis separately. If a node is only clipped on a single axis, the other axis is given `-f32::INFINITY` to `f32::INFINITY` clipping bounds. ## Migration Guide The `Style` property `Overflow` is now a struct with `x` and `y` fields, that allow for per-axis overflow control. Use these helper functions to replace the variants of `Overflow`: * Replace `Overflow::Visible` with `Overflow::visible()` * Replace `Overflow::Hidden` with `Overflow::clip()`
2023-04-17 22:23:52 +00:00
[[example]]
name = "overflow"
path = "examples/ui/overflow.rs"
doc-scrape-examples = true
Split UI `Overflow` by axis (#8095) # Objective Split the UI overflow enum so that overflow can be set for each axis separately. ## Solution Change `Overflow` from an enum to a struct with `x` and `y` `OverflowAxis` fields, where `OverflowAxis` is an enum with `Clip` and `Visible` variants. Modify `update_clipping` to calculate clipping for each axis separately. If only one axis is clipped, the other axis is given infinite bounds. <img width="642" alt="overflow" src="https://user-images.githubusercontent.com/27962798/227592983-568cf76f-7e40-48c4-a511-43c886f5e431.PNG"> --- ## Changelog * Split the UI overflow implementation so overflow can be set for each axis separately. * Added the enum `OverflowAxis` with `Clip` and `Visible` variants. * Changed `Overflow` to a struct with `x` and `y` fields of type `OverflowAxis`. * `Overflow` has new methods `visible()` and `hidden()` that replace its previous `Clip` and `Visible` variants. * Added `Overflow` helper methods `clip_x()` and `clip_y()` that return a new `Overflow` value with the given axis clipped. * Modified `update_clipping` so it calculates clipping for each axis separately. If a node is only clipped on a single axis, the other axis is given `-f32::INFINITY` to `f32::INFINITY` clipping bounds. ## Migration Guide The `Style` property `Overflow` is now a struct with `x` and `y` fields, that allow for per-axis overflow control. Use these helper functions to replace the variants of `Overflow`: * Replace `Overflow::Visible` with `Overflow::visible()` * Replace `Overflow::Hidden` with `Overflow::clip()`
2023-04-17 22:23:52 +00:00
[package.metadata.example.overflow]
name = "Overflow"
description = "Simple example demonstrating overflow behavior"
category = "UI (User Interface)"
wasm = true
[[example]]
name = "overflow_debug"
path = "examples/ui/overflow_debug.rs"
doc-scrape-examples = true
[package.metadata.example.overflow_debug]
name = "Overflow and Clipping Debug"
description = "An example to debug overflow and clipping behavior"
category = "UI (User Interface)"
wasm = true
[[example]]
name = "relative_cursor_position"
path = "examples/ui/relative_cursor_position.rs"
doc-scrape-examples = true
[package.metadata.example.relative_cursor_position]
name = "Relative Cursor Position"
description = "Showcases the RelativeCursorPosition component"
category = "UI (User Interface)"
wasm = true
[[example]]
name = "size_constraints"
path = "examples/ui/size_constraints.rs"
doc-scrape-examples = true
[package.metadata.example.size_constraints]
name = "Size Constraints"
description = "Demonstrates how the to use the size constraints to control the size of a UI node."
category = "UI (User Interface)"
wasm = true
2020-05-13 20:09:32 +00:00
[[example]]
name = "text"
path = "examples/ui/text.rs"
doc-scrape-examples = true
2020-05-13 20:09:32 +00:00
[package.metadata.example.text]
name = "Text"
description = "Illustrates creating and updating text"
category = "UI (User Interface)"
wasm = true
[[example]]
name = "text_debug"
path = "examples/ui/text_debug.rs"
doc-scrape-examples = true
[package.metadata.example.text_debug]
name = "Text Debug"
description = "An example for debugging text layout"
category = "UI (User Interface)"
wasm = true
[[example]]
name = "flex_layout"
path = "examples/ui/flex_layout.rs"
doc-scrape-examples = true
[package.metadata.example.flex_layout]
name = "Flex Layout"
description = "Demonstrates how the AlignItems and JustifyContent properties can be composed to layout nodes and position text"
category = "UI (User Interface)"
Add CSS Grid support to `bevy_ui` (#8026) # Objective An easy way to create 2D grid layouts ## Solution Enable the `grid` feature in Taffy and add new style types for defining grids. ## Notes - ~I'm having a bit of trouble getting `#[derive(Reflect)]` to work properly. Help with that would be appreciated (EDIT: got it to compile by ignoring the problematic fields, but this presumably can't be merged).~ This is now fixed - ~The alignment types now have a `Normal` variant because I couldn't get reflect to work with `Option`.~ I've decided to stick with the flattened variant, as it saves a level of wrapping when authoring styles. But I've renamed the variants from `Normal` to `Default`. - ~This currently exposes a simplified API on top of grid. In particular the following is not currently supported:~ - ~Negative grid indices~ Now supported. - ~Custom `end` values for grid placement (you can only use `start` and `span`)~ Now supported - ~`minmax()` track sizing functions~ minmax is now support through a `GridTrack::minmax()` constructor - ~`repeat()`~ repeat is now implemented as `RepeatedGridTrack` - ~Documentation still needs to be improved.~ An initial pass over the documentation has been completed. ## Screenshot <img width="846" alt="Screenshot 2023-03-10 at 17 56 21" src="https://user-images.githubusercontent.com/1007307/224435332-69aa9eac-123d-4856-b75d-5449d3f1d426.png"> --- ## Changelog - Support for CSS Grid layout added to `bevy_ui` --------- Co-authored-by: Rob Parrett <robparrett@gmail.com> Co-authored-by: Andreas Weibye <13300393+Weibye@users.noreply.github.com>
2023-04-17 16:21:38 +00:00
wasm = true
[[example]]
name = "text_wrap_debug"
path = "examples/ui/text_wrap_debug.rs"
doc-scrape-examples = true
[package.metadata.example.text_wrap_debug]
name = "Text Wrap Debug"
description = "Demonstrates text wrapping"
category = "UI (User Interface)"
wasm = true
Add CSS Grid support to `bevy_ui` (#8026) # Objective An easy way to create 2D grid layouts ## Solution Enable the `grid` feature in Taffy and add new style types for defining grids. ## Notes - ~I'm having a bit of trouble getting `#[derive(Reflect)]` to work properly. Help with that would be appreciated (EDIT: got it to compile by ignoring the problematic fields, but this presumably can't be merged).~ This is now fixed - ~The alignment types now have a `Normal` variant because I couldn't get reflect to work with `Option`.~ I've decided to stick with the flattened variant, as it saves a level of wrapping when authoring styles. But I've renamed the variants from `Normal` to `Default`. - ~This currently exposes a simplified API on top of grid. In particular the following is not currently supported:~ - ~Negative grid indices~ Now supported. - ~Custom `end` values for grid placement (you can only use `start` and `span`)~ Now supported - ~`minmax()` track sizing functions~ minmax is now support through a `GridTrack::minmax()` constructor - ~`repeat()`~ repeat is now implemented as `RepeatedGridTrack` - ~Documentation still needs to be improved.~ An initial pass over the documentation has been completed. ## Screenshot <img width="846" alt="Screenshot 2023-03-10 at 17 56 21" src="https://user-images.githubusercontent.com/1007307/224435332-69aa9eac-123d-4856-b75d-5449d3f1d426.png"> --- ## Changelog - Support for CSS Grid layout added to `bevy_ui` --------- Co-authored-by: Rob Parrett <robparrett@gmail.com> Co-authored-by: Andreas Weibye <13300393+Weibye@users.noreply.github.com>
2023-04-17 16:21:38 +00:00
[[example]]
name = "grid"
path = "examples/ui/grid.rs"
doc-scrape-examples = true
Add CSS Grid support to `bevy_ui` (#8026) # Objective An easy way to create 2D grid layouts ## Solution Enable the `grid` feature in Taffy and add new style types for defining grids. ## Notes - ~I'm having a bit of trouble getting `#[derive(Reflect)]` to work properly. Help with that would be appreciated (EDIT: got it to compile by ignoring the problematic fields, but this presumably can't be merged).~ This is now fixed - ~The alignment types now have a `Normal` variant because I couldn't get reflect to work with `Option`.~ I've decided to stick with the flattened variant, as it saves a level of wrapping when authoring styles. But I've renamed the variants from `Normal` to `Default`. - ~This currently exposes a simplified API on top of grid. In particular the following is not currently supported:~ - ~Negative grid indices~ Now supported. - ~Custom `end` values for grid placement (you can only use `start` and `span`)~ Now supported - ~`minmax()` track sizing functions~ minmax is now support through a `GridTrack::minmax()` constructor - ~`repeat()`~ repeat is now implemented as `RepeatedGridTrack` - ~Documentation still needs to be improved.~ An initial pass over the documentation has been completed. ## Screenshot <img width="846" alt="Screenshot 2023-03-10 at 17 56 21" src="https://user-images.githubusercontent.com/1007307/224435332-69aa9eac-123d-4856-b75d-5449d3f1d426.png"> --- ## Changelog - Support for CSS Grid layout added to `bevy_ui` --------- Co-authored-by: Rob Parrett <robparrett@gmail.com> Co-authored-by: Andreas Weibye <13300393+Weibye@users.noreply.github.com>
2023-04-17 16:21:38 +00:00
[package.metadata.example.grid]
name = "CSS Grid"
description = "An example for CSS Grid layout"
Add CSS Grid support to `bevy_ui` (#8026) # Objective An easy way to create 2D grid layouts ## Solution Enable the `grid` feature in Taffy and add new style types for defining grids. ## Notes - ~I'm having a bit of trouble getting `#[derive(Reflect)]` to work properly. Help with that would be appreciated (EDIT: got it to compile by ignoring the problematic fields, but this presumably can't be merged).~ This is now fixed - ~The alignment types now have a `Normal` variant because I couldn't get reflect to work with `Option`.~ I've decided to stick with the flattened variant, as it saves a level of wrapping when authoring styles. But I've renamed the variants from `Normal` to `Default`. - ~This currently exposes a simplified API on top of grid. In particular the following is not currently supported:~ - ~Negative grid indices~ Now supported. - ~Custom `end` values for grid placement (you can only use `start` and `span`)~ Now supported - ~`minmax()` track sizing functions~ minmax is now support through a `GridTrack::minmax()` constructor - ~`repeat()`~ repeat is now implemented as `RepeatedGridTrack` - ~Documentation still needs to be improved.~ An initial pass over the documentation has been completed. ## Screenshot <img width="846" alt="Screenshot 2023-03-10 at 17 56 21" src="https://user-images.githubusercontent.com/1007307/224435332-69aa9eac-123d-4856-b75d-5449d3f1d426.png"> --- ## Changelog - Support for CSS Grid layout added to `bevy_ui` --------- Co-authored-by: Rob Parrett <robparrett@gmail.com> Co-authored-by: Andreas Weibye <13300393+Weibye@users.noreply.github.com>
2023-04-17 16:21:38 +00:00
category = "UI (User Interface)"
wasm = true
2020-05-01 20:12:47 +00:00
[[example]]
name = "transparency_ui"
path = "examples/ui/transparency_ui.rs"
doc-scrape-examples = true
[package.metadata.example.transparency_ui]
name = "Transparency UI"
description = "Demonstrates transparency for UI"
category = "UI (User Interface)"
wasm = true
Add z-index support with a predictable UI stack (#5877) # Objective Add consistent UI rendering and interaction where deep nodes inside two different hierarchies will never render on top of one-another by default and offer an escape hatch (z-index) for nodes to change their depth. ## The problem with current implementation The current implementation of UI rendering is broken in that regard, mainly because [it sets the Z value of the `Transform` component based on a "global Z" space](https://github.com/bevyengine/bevy/blob/main/crates/bevy_ui/src/update.rs#L43) shared by all nodes in the UI. This doesn't account for the fact that each node's final `GlobalTransform` value will be relative to its parent. This effectively makes the depth unpredictable when two deep trees are rendered on top of one-another. At the moment, it's also up to each part of the UI code to sort all of the UI nodes. The solution that's offered here does the full sorting of UI node entities once and offers the result through a resource so that all systems can use it. ## Solution ### New ZIndex component This adds a new optional `ZIndex` enum component for nodes which offers two mechanism: - `ZIndex::Local(i32)`: Overrides the depth of the node relative to its siblings. - `ZIndex::Global(i32)`: Overrides the depth of the node relative to the UI root. This basically allows any node in the tree to "escape" the parent and be ordered relative to the entire UI. Note that in the current implementation, omitting `ZIndex` on a node has the same result as adding `ZIndex::Local(0)`. Additionally, the "global" stacking context is essentially a way to add your node to the root stacking context, so using `ZIndex::Local(n)` on a root node (one without parent) will share that space with all nodes using `Index::Global(n)`. ### New UiStack resource This adds a new `UiStack` resource which is calculated from both hierarchy and `ZIndex` during UI update and contains a vector of all node entities in the UI, ordered by depth (from farthest from camera to closest). This is exposed publicly by the bevy_ui crate with the hope that it can be used for consistent ordering and to reduce the amount of sorting that needs to be done by UI systems (i.e. instead of sorting everything by `global_transform.z` in every system, this array can be iterated over). ### New z_index example This also adds a new z_index example that showcases the new `ZIndex` component. It's also a good general demo of the new UI stack system, because making this kind of UI was very broken with the old system (e.g. nodes would render on top of each other, not respecting hierarchy or insert order at all). ![image](https://user-images.githubusercontent.com/1060971/189015985-8ea8f989-0e9d-4601-a7e0-4a27a43a53f9.png) --- ## Changelog - Added the `ZIndex` component to bevy_ui. - Added the `UiStack` resource to bevy_ui, and added implementation in a new `stack.rs` module. - Removed the previous Z updating system from bevy_ui, because it was replaced with the above. - Changed bevy_ui rendering to use UiStack instead of z ordering. - Changed bevy_ui focus/interaction system to use UiStack instead of z ordering. - Added a new z_index example. ## ZIndex demo Here's a demo I wrote to test these features https://user-images.githubusercontent.com/1060971/188329295-d7beebd6-9aee-43ab-821e-d437df5dbe8a.mp4 Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-11-02 22:06:04 +00:00
[[example]]
name = "z_index"
path = "examples/ui/z_index.rs"
doc-scrape-examples = true
Add z-index support with a predictable UI stack (#5877) # Objective Add consistent UI rendering and interaction where deep nodes inside two different hierarchies will never render on top of one-another by default and offer an escape hatch (z-index) for nodes to change their depth. ## The problem with current implementation The current implementation of UI rendering is broken in that regard, mainly because [it sets the Z value of the `Transform` component based on a "global Z" space](https://github.com/bevyengine/bevy/blob/main/crates/bevy_ui/src/update.rs#L43) shared by all nodes in the UI. This doesn't account for the fact that each node's final `GlobalTransform` value will be relative to its parent. This effectively makes the depth unpredictable when two deep trees are rendered on top of one-another. At the moment, it's also up to each part of the UI code to sort all of the UI nodes. The solution that's offered here does the full sorting of UI node entities once and offers the result through a resource so that all systems can use it. ## Solution ### New ZIndex component This adds a new optional `ZIndex` enum component for nodes which offers two mechanism: - `ZIndex::Local(i32)`: Overrides the depth of the node relative to its siblings. - `ZIndex::Global(i32)`: Overrides the depth of the node relative to the UI root. This basically allows any node in the tree to "escape" the parent and be ordered relative to the entire UI. Note that in the current implementation, omitting `ZIndex` on a node has the same result as adding `ZIndex::Local(0)`. Additionally, the "global" stacking context is essentially a way to add your node to the root stacking context, so using `ZIndex::Local(n)` on a root node (one without parent) will share that space with all nodes using `Index::Global(n)`. ### New UiStack resource This adds a new `UiStack` resource which is calculated from both hierarchy and `ZIndex` during UI update and contains a vector of all node entities in the UI, ordered by depth (from farthest from camera to closest). This is exposed publicly by the bevy_ui crate with the hope that it can be used for consistent ordering and to reduce the amount of sorting that needs to be done by UI systems (i.e. instead of sorting everything by `global_transform.z` in every system, this array can be iterated over). ### New z_index example This also adds a new z_index example that showcases the new `ZIndex` component. It's also a good general demo of the new UI stack system, because making this kind of UI was very broken with the old system (e.g. nodes would render on top of each other, not respecting hierarchy or insert order at all). ![image](https://user-images.githubusercontent.com/1060971/189015985-8ea8f989-0e9d-4601-a7e0-4a27a43a53f9.png) --- ## Changelog - Added the `ZIndex` component to bevy_ui. - Added the `UiStack` resource to bevy_ui, and added implementation in a new `stack.rs` module. - Removed the previous Z updating system from bevy_ui, because it was replaced with the above. - Changed bevy_ui rendering to use UiStack instead of z ordering. - Changed bevy_ui focus/interaction system to use UiStack instead of z ordering. - Added a new z_index example. ## ZIndex demo Here's a demo I wrote to test these features https://user-images.githubusercontent.com/1060971/188329295-d7beebd6-9aee-43ab-821e-d437df5dbe8a.mp4 Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2022-11-02 22:06:04 +00:00
[package.metadata.example.z_index]
name = "UI Z-Index"
description = "Demonstrates how to control the relative depth (z-position) of UI elements"
category = "UI (User Interface)"
wasm = true
[[example]]
2020-05-01 20:12:47 +00:00
name = "ui"
path = "examples/ui/ui.rs"
doc-scrape-examples = true
2020-05-01 20:12:47 +00:00
[package.metadata.example.ui]
name = "UI"
description = "Illustrates various features of Bevy UI"
category = "UI (User Interface)"
wasm = true
[[example]]
name = "ui_scaling"
path = "examples/ui/ui_scaling.rs"
doc-scrape-examples = true
[package.metadata.example.ui_scaling]
name = "UI Scaling"
description = "Illustrates how to scale the UI"
category = "UI (User Interface)"
wasm = true
[[example]]
name = "ui_texture_atlas"
path = "examples/ui/ui_texture_atlas.rs"
doc-scrape-examples = true
[package.metadata.example.ui_texture_atlas]
name = "UI Texture Atlas"
description = "Illustrates how to use TextureAtlases in UI"
category = "UI (User Interface)"
wasm = true
[[example]]
name = "viewport_debug"
path = "examples/ui/viewport_debug.rs"
doc-scrape-examples = true
[package.metadata.example.viewport_debug]
name = "Viewport Debug"
description = "An example for debugging viewport coordinates"
category = "UI (User Interface)"
wasm = true
Cleanup of Markdown Files and add CI Checking (#1463) I have run the VSCode Extension [markdownlint](https://marketplace.visualstudio.com/items?itemName=DavidAnson.vscode-markdownlint) on all Markdown Files in the Repo. The provided Rules are documented here: https://github.com/DavidAnson/markdownlint/blob/v0.23.1/doc/Rules.md Rules I didn't follow/fix: * MD024/no-duplicate-heading * Changelog: Here Heading will always repeat. * Examples Readme: Platform-specific documentation should be symmetrical. * MD025/single-title * MD026/no-trailing-punctuation * Caused by the ! in "Hello, World!". * MD033/no-inline-html * The plugins_guidlines file does need HTML, so the shown badges aren't downscaled too much. * ~~MD036/no-emphasis-as-heading:~~ * ~~This Warning only Appears in the Github Issue Templates and can be ignored.~~ * ~~MD041/first-line-heading~~ * ~~Only appears in the Readme for the AlienCake example Assets, which is unimportant.~~ --- I also sorted the Examples in the Readme and Cargo.toml in this order/Priority: * Topic/Folder * Introductionary Examples * Alphabetical Order The explanation for each case, where it isn't Alphabetical : * Diagnostics * log_diagnostics: The usage of inbuild Diagnostics is more important than creating your own. * ECS (Entity Component System) * ecs_guide: The guide should be read, before diving into other Features. * Reflection * reflection: Basic Explanation should be read, before more advanced Topics. * WASM Examples * hello_wasm: It's "Hello, World!".
2021-02-22 04:50:05 +00:00
# Window
2020-06-25 22:24:27 +00:00
[[example]]
name = "clear_color"
path = "examples/window/clear_color.rs"
doc-scrape-examples = true
[package.metadata.example.clear_color]
name = "Clear Color"
description = "Creates a solid color window"
category = "Window"
wasm = true
Reduce power usage with configurable event loop (#3974) # Objective - Reduce power usage for games when not focused. - Reduce power usage to ~0 when a desktop application is minimized (opt-in). - Reduce power usage when focused, only updating on a `winit` event, or the user sends a redraw request. (opt-in) https://user-images.githubusercontent.com/2632925/156904387-ec47d7de-7f06-4c6f-8aaf-1e952c1153a2.mp4 Note resource usage in the Task Manager in the above video. ## Solution - Added a type `UpdateMode` that allows users to specify how the winit event loop is updated, without exposing winit types. - Added two fields to `WinitConfig`, both with the `UpdateMode` type. One configures how the application updates when focused, and the other configures how the application behaves when it is not focused. Users can modify this resource manually to set the type of event loop control flow they want. - For convenience, two functions were added to `WinitConfig`, that provide reasonable presets: `game()` (default) and `desktop_app()`. - The `game()` preset, which is used by default, is unchanged from current behavior with one exception: when the app is out of focus the app updates at a minimum of 10fps, or every time a winit event is received. This has a huge positive impact on power use and responsiveness on my machine, which will otherwise continue running the app at many hundreds of fps when out of focus or minimized. - The `desktop_app()` preset is fully reactive, only updating when user input (winit event) is supplied or a `RedrawRequest` event is sent. When the app is out of focus, it only updates on `Window` events - i.e. any winit event that directly interacts with the window. What this means in practice is that the app uses *zero* resources when minimized or not interacted with, but still updates fluidly when the app is out of focus and the user mouses over the application. - Added a `RedrawRequest` event so users can force an update even if there are no events. This is useful in an application when you want to, say, run an animation even when the user isn't providing input. - Added an example `low_power` to demonstrate these changes ## Usage Configuring the event loop: ```rs use bevy::winit::{WinitConfig}; // ... .insert_resource(WinitConfig::desktop_app()) // preset // or .insert_resource(WinitConfig::game()) // preset // or .insert_resource(WinitConfig{ .. }) // manual ``` Requesting a redraw: ```rs use bevy::window::RequestRedraw; // ... fn request_redraw(mut event: EventWriter<RequestRedraw>) { event.send(RequestRedraw); } ``` ## Other details - Because we have a single event loop for multiple windows, every time I've mentioned "focused" above, I more precisely mean, "if at least one bevy window is focused". - Due to a platform bug in winit (https://github.com/rust-windowing/winit/issues/1619), we can't simply use `Window::request_redraw()`. As a workaround, this PR will temporarily set the window mode to `Poll` when a redraw is requested. This is then reset to the user's `WinitConfig` setting on the next frame.
2022-03-07 23:32:05 +00:00
[[example]]
name = "low_power"
path = "examples/window/low_power.rs"
doc-scrape-examples = true
Reduce power usage with configurable event loop (#3974) # Objective - Reduce power usage for games when not focused. - Reduce power usage to ~0 when a desktop application is minimized (opt-in). - Reduce power usage when focused, only updating on a `winit` event, or the user sends a redraw request. (opt-in) https://user-images.githubusercontent.com/2632925/156904387-ec47d7de-7f06-4c6f-8aaf-1e952c1153a2.mp4 Note resource usage in the Task Manager in the above video. ## Solution - Added a type `UpdateMode` that allows users to specify how the winit event loop is updated, without exposing winit types. - Added two fields to `WinitConfig`, both with the `UpdateMode` type. One configures how the application updates when focused, and the other configures how the application behaves when it is not focused. Users can modify this resource manually to set the type of event loop control flow they want. - For convenience, two functions were added to `WinitConfig`, that provide reasonable presets: `game()` (default) and `desktop_app()`. - The `game()` preset, which is used by default, is unchanged from current behavior with one exception: when the app is out of focus the app updates at a minimum of 10fps, or every time a winit event is received. This has a huge positive impact on power use and responsiveness on my machine, which will otherwise continue running the app at many hundreds of fps when out of focus or minimized. - The `desktop_app()` preset is fully reactive, only updating when user input (winit event) is supplied or a `RedrawRequest` event is sent. When the app is out of focus, it only updates on `Window` events - i.e. any winit event that directly interacts with the window. What this means in practice is that the app uses *zero* resources when minimized or not interacted with, but still updates fluidly when the app is out of focus and the user mouses over the application. - Added a `RedrawRequest` event so users can force an update even if there are no events. This is useful in an application when you want to, say, run an animation even when the user isn't providing input. - Added an example `low_power` to demonstrate these changes ## Usage Configuring the event loop: ```rs use bevy::winit::{WinitConfig}; // ... .insert_resource(WinitConfig::desktop_app()) // preset // or .insert_resource(WinitConfig::game()) // preset // or .insert_resource(WinitConfig{ .. }) // manual ``` Requesting a redraw: ```rs use bevy::window::RequestRedraw; // ... fn request_redraw(mut event: EventWriter<RequestRedraw>) { event.send(RequestRedraw); } ``` ## Other details - Because we have a single event loop for multiple windows, every time I've mentioned "focused" above, I more precisely mean, "if at least one bevy window is focused". - Due to a platform bug in winit (https://github.com/rust-windowing/winit/issues/1619), we can't simply use `Window::request_redraw()`. As a workaround, this PR will temporarily set the window mode to `Poll` when a redraw is requested. This is then reset to the user's `WinitConfig` setting on the next frame.
2022-03-07 23:32:05 +00:00
[package.metadata.example.low_power]
name = "Low Power"
description = "Demonstrates settings to reduce power use for bevy applications"
category = "Window"
wasm = true
[[example]]
name = "multiple_windows"
path = "examples/window/multiple_windows.rs"
doc-scrape-examples = true
2020-06-25 22:24:27 +00:00
[package.metadata.example.multiple_windows]
name = "Multiple Windows"
description = "Demonstrates creating multiple windows, and rendering to them"
category = "Window"
wasm = false
[[example]]
name = "scale_factor_override"
path = "examples/window/scale_factor_override.rs"
doc-scrape-examples = true
[package.metadata.example.scale_factor_override]
name = "Scale Factor Override"
description = "Illustrates how to customize the default window settings"
category = "Window"
wasm = true
[[example]]
name = "screenshot"
path = "examples/window/screenshot.rs"
doc-scrape-examples = true
[package.metadata.example.screenshot]
name = "Screenshot"
description = "Shows how to save screenshots to disk"
category = "Window"
wasm = true
[[example]]
name = "transparent_window"
path = "examples/window/transparent_window.rs"
doc-scrape-examples = true
[package.metadata.example.transparent_window]
name = "Transparent Window"
description = "Illustrates making the window transparent and hiding the window decoration"
category = "Window"
wasm = false
[[example]]
name = "window_settings"
path = "examples/window/window_settings.rs"
doc-scrape-examples = true
[package.metadata.example.window_settings]
name = "Window Settings"
description = "Demonstrates customizing default window settings"
category = "Window"
wasm = true
Add an example to test small window sizes (#3597) # Objective We keep getting issues where things break at small window sizes, e.g #3368 (caused by #3153), #3596 ('caused' by #3545) ## Solution - Add a test that we can make small windows. Currently, this fails on my machine with some quite scary vulkan errors: ``` 2022-01-08T22:55:13.770261Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 (0x7cd0911d)] Validation Error: [ VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 ] Object 0: handle = 0x1adbd410a60, type = VK_OBJECT_TYPE_DEVICE; | MessageID = 0x7cd0911d | vkCreateSwapchainKHR() called with imageExtent = (225,60), which is outside the bounds returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR(): currentExtent = (225,56), minImageExtent = (225,56), maxImageExtent = (225,56). The Vulkan spec states: imageExtent must be between minImageExtent and maxImageExtent, inclusive, where minImageExtent and maxImageExtent are members of the VkSurfaceCapabilitiesKHR structure returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR for the surface (https://vulkan.lunarg.com/doc/view/1.2.198.1/windows/1.2-extensions/vkspec.html#VUID-VkSwapchainCreateInfoKHR-imageExtent-01274) 2022-01-08T22:55:13.770808Z ERROR wgpu_hal::vulkan::instance: objects: (type: DEVICE, hndl: 0x1adbd410a60, name: ?) 2022-01-08T22:55:13.787403Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 (0x7cd0911d)] Validation Error: [ VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 ] Object 0: handle = 0x1adbd410a60, type = VK_OBJECT_TYPE_DEVICE; | MessageID = 0x7cd0911d | vkCreateSwapchainKHR() called with imageExtent = (225,56), which is outside the bounds returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR(): currentExtent = (225,52), minImageExtent = (225,52), maxImageExtent = (225,52). The Vulkan spec states: imageExtent must be between minImageExtent and maxImageExtent, inclusive, where minImageExtent and maxImageExtent are members of the VkSurfaceCapabilitiesKHR structure returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR for the surface (https://vulkan.lunarg.com/doc/view/1.2.198.1/windows/1.2-extensions/vkspec.html#VUID-VkSwapchainCreateInfoKHR-imageExtent-01274) ``` etc. This might be a new issue here, although I'm surprised it's vulkan giving this error; wgpu should stop it if this is illegal.
2022-04-26 22:15:24 +00:00
[[example]]
name = "resizing"
path = "tests/window/resizing.rs"
doc-scrape-examples = true
Add an example to test small window sizes (#3597) # Objective We keep getting issues where things break at small window sizes, e.g #3368 (caused by #3153), #3596 ('caused' by #3545) ## Solution - Add a test that we can make small windows. Currently, this fails on my machine with some quite scary vulkan errors: ``` 2022-01-08T22:55:13.770261Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 (0x7cd0911d)] Validation Error: [ VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 ] Object 0: handle = 0x1adbd410a60, type = VK_OBJECT_TYPE_DEVICE; | MessageID = 0x7cd0911d | vkCreateSwapchainKHR() called with imageExtent = (225,60), which is outside the bounds returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR(): currentExtent = (225,56), minImageExtent = (225,56), maxImageExtent = (225,56). The Vulkan spec states: imageExtent must be between minImageExtent and maxImageExtent, inclusive, where minImageExtent and maxImageExtent are members of the VkSurfaceCapabilitiesKHR structure returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR for the surface (https://vulkan.lunarg.com/doc/view/1.2.198.1/windows/1.2-extensions/vkspec.html#VUID-VkSwapchainCreateInfoKHR-imageExtent-01274) 2022-01-08T22:55:13.770808Z ERROR wgpu_hal::vulkan::instance: objects: (type: DEVICE, hndl: 0x1adbd410a60, name: ?) 2022-01-08T22:55:13.787403Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 (0x7cd0911d)] Validation Error: [ VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 ] Object 0: handle = 0x1adbd410a60, type = VK_OBJECT_TYPE_DEVICE; | MessageID = 0x7cd0911d | vkCreateSwapchainKHR() called with imageExtent = (225,56), which is outside the bounds returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR(): currentExtent = (225,52), minImageExtent = (225,52), maxImageExtent = (225,52). The Vulkan spec states: imageExtent must be between minImageExtent and maxImageExtent, inclusive, where minImageExtent and maxImageExtent are members of the VkSurfaceCapabilitiesKHR structure returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR for the surface (https://vulkan.lunarg.com/doc/view/1.2.198.1/windows/1.2-extensions/vkspec.html#VUID-VkSwapchainCreateInfoKHR-imageExtent-01274) ``` etc. This might be a new issue here, although I'm surprised it's vulkan giving this error; wgpu should stop it if this is illegal.
2022-04-26 22:15:24 +00:00
[package.metadata.example.resizing]
hidden = true
Add an example to test small window sizes (#3597) # Objective We keep getting issues where things break at small window sizes, e.g #3368 (caused by #3153), #3596 ('caused' by #3545) ## Solution - Add a test that we can make small windows. Currently, this fails on my machine with some quite scary vulkan errors: ``` 2022-01-08T22:55:13.770261Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 (0x7cd0911d)] Validation Error: [ VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 ] Object 0: handle = 0x1adbd410a60, type = VK_OBJECT_TYPE_DEVICE; | MessageID = 0x7cd0911d | vkCreateSwapchainKHR() called with imageExtent = (225,60), which is outside the bounds returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR(): currentExtent = (225,56), minImageExtent = (225,56), maxImageExtent = (225,56). The Vulkan spec states: imageExtent must be between minImageExtent and maxImageExtent, inclusive, where minImageExtent and maxImageExtent are members of the VkSurfaceCapabilitiesKHR structure returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR for the surface (https://vulkan.lunarg.com/doc/view/1.2.198.1/windows/1.2-extensions/vkspec.html#VUID-VkSwapchainCreateInfoKHR-imageExtent-01274) 2022-01-08T22:55:13.770808Z ERROR wgpu_hal::vulkan::instance: objects: (type: DEVICE, hndl: 0x1adbd410a60, name: ?) 2022-01-08T22:55:13.787403Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 (0x7cd0911d)] Validation Error: [ VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 ] Object 0: handle = 0x1adbd410a60, type = VK_OBJECT_TYPE_DEVICE; | MessageID = 0x7cd0911d | vkCreateSwapchainKHR() called with imageExtent = (225,56), which is outside the bounds returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR(): currentExtent = (225,52), minImageExtent = (225,52), maxImageExtent = (225,52). The Vulkan spec states: imageExtent must be between minImageExtent and maxImageExtent, inclusive, where minImageExtent and maxImageExtent are members of the VkSurfaceCapabilitiesKHR structure returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR for the surface (https://vulkan.lunarg.com/doc/view/1.2.198.1/windows/1.2-extensions/vkspec.html#VUID-VkSwapchainCreateInfoKHR-imageExtent-01274) ``` etc. This might be a new issue here, although I'm surprised it's vulkan giving this error; wgpu should stop it if this is illegal.
2022-04-26 22:15:24 +00:00
[[example]]
name = "minimising"
path = "tests/window/minimising.rs"
doc-scrape-examples = true
Add an example to test small window sizes (#3597) # Objective We keep getting issues where things break at small window sizes, e.g #3368 (caused by #3153), #3596 ('caused' by #3545) ## Solution - Add a test that we can make small windows. Currently, this fails on my machine with some quite scary vulkan errors: ``` 2022-01-08T22:55:13.770261Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 (0x7cd0911d)] Validation Error: [ VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 ] Object 0: handle = 0x1adbd410a60, type = VK_OBJECT_TYPE_DEVICE; | MessageID = 0x7cd0911d | vkCreateSwapchainKHR() called with imageExtent = (225,60), which is outside the bounds returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR(): currentExtent = (225,56), minImageExtent = (225,56), maxImageExtent = (225,56). The Vulkan spec states: imageExtent must be between minImageExtent and maxImageExtent, inclusive, where minImageExtent and maxImageExtent are members of the VkSurfaceCapabilitiesKHR structure returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR for the surface (https://vulkan.lunarg.com/doc/view/1.2.198.1/windows/1.2-extensions/vkspec.html#VUID-VkSwapchainCreateInfoKHR-imageExtent-01274) 2022-01-08T22:55:13.770808Z ERROR wgpu_hal::vulkan::instance: objects: (type: DEVICE, hndl: 0x1adbd410a60, name: ?) 2022-01-08T22:55:13.787403Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 (0x7cd0911d)] Validation Error: [ VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 ] Object 0: handle = 0x1adbd410a60, type = VK_OBJECT_TYPE_DEVICE; | MessageID = 0x7cd0911d | vkCreateSwapchainKHR() called with imageExtent = (225,56), which is outside the bounds returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR(): currentExtent = (225,52), minImageExtent = (225,52), maxImageExtent = (225,52). The Vulkan spec states: imageExtent must be between minImageExtent and maxImageExtent, inclusive, where minImageExtent and maxImageExtent are members of the VkSurfaceCapabilitiesKHR structure returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR for the surface (https://vulkan.lunarg.com/doc/view/1.2.198.1/windows/1.2-extensions/vkspec.html#VUID-VkSwapchainCreateInfoKHR-imageExtent-01274) ``` etc. This might be a new issue here, although I'm surprised it's vulkan giving this error; wgpu should stop it if this is illegal.
2022-04-26 22:15:24 +00:00
[package.metadata.example.minimising]
hidden = true
Add an example to test small window sizes (#3597) # Objective We keep getting issues where things break at small window sizes, e.g #3368 (caused by #3153), #3596 ('caused' by #3545) ## Solution - Add a test that we can make small windows. Currently, this fails on my machine with some quite scary vulkan errors: ``` 2022-01-08T22:55:13.770261Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 (0x7cd0911d)] Validation Error: [ VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 ] Object 0: handle = 0x1adbd410a60, type = VK_OBJECT_TYPE_DEVICE; | MessageID = 0x7cd0911d | vkCreateSwapchainKHR() called with imageExtent = (225,60), which is outside the bounds returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR(): currentExtent = (225,56), minImageExtent = (225,56), maxImageExtent = (225,56). The Vulkan spec states: imageExtent must be between minImageExtent and maxImageExtent, inclusive, where minImageExtent and maxImageExtent are members of the VkSurfaceCapabilitiesKHR structure returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR for the surface (https://vulkan.lunarg.com/doc/view/1.2.198.1/windows/1.2-extensions/vkspec.html#VUID-VkSwapchainCreateInfoKHR-imageExtent-01274) 2022-01-08T22:55:13.770808Z ERROR wgpu_hal::vulkan::instance: objects: (type: DEVICE, hndl: 0x1adbd410a60, name: ?) 2022-01-08T22:55:13.787403Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 (0x7cd0911d)] Validation Error: [ VUID-VkSwapchainCreateInfoKHR-imageExtent-01274 ] Object 0: handle = 0x1adbd410a60, type = VK_OBJECT_TYPE_DEVICE; | MessageID = 0x7cd0911d | vkCreateSwapchainKHR() called with imageExtent = (225,56), which is outside the bounds returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR(): currentExtent = (225,52), minImageExtent = (225,52), maxImageExtent = (225,52). The Vulkan spec states: imageExtent must be between minImageExtent and maxImageExtent, inclusive, where minImageExtent and maxImageExtent are members of the VkSurfaceCapabilitiesKHR structure returned by vkGetPhysicalDeviceSurfaceCapabilitiesKHR for the surface (https://vulkan.lunarg.com/doc/view/1.2.198.1/windows/1.2-extensions/vkspec.html#VUID-VkSwapchainCreateInfoKHR-imageExtent-01274) ``` etc. This might be a new issue here, although I'm surprised it's vulkan giving this error; wgpu should stop it if this is illegal.
2022-04-26 22:15:24 +00:00
[[example]]
name = "window_resizing"
path = "examples/window/window_resizing.rs"
doc-scrape-examples = true
[[example]]
name = "fallback_image"
path = "examples/shader/fallback_image.rs"
doc-scrape-examples = true
[package.metadata.example.fallback_image]
hidden = true
[package.metadata.example.window_resizing]
name = "Window Resizing"
description = "Demonstrates resizing and responding to resizing a window"
category = "Window"
wasm = true
[[example]]
name = "ui_material"
path = "examples/ui/ui_material.rs"
doc-scrape-examples = true
[package.metadata.example.ui_material]
name = "UI Material"
description = "Demonstrates creating and using custom Ui materials"
category = "UI (User Interface)"
wasm = true
[profile.wasm-release]
inherits = "release"
opt-level = "z"
lto = "fat"
codegen-units = 1
[profile.stress-test]
inherits = "release"
lto = "fat"
panic = "abort"
[package.metadata.docs.rs]
cargo-args = ["-Zunstable-options", "-Zrustdoc-scrape-examples"]