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https://github.com/bevyengine/bevy
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29 commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Pablo Reinhardt
|
d96a9d15f6
|
Migrate from Query::single and friends to Single (#15872)
# Objective - closes #15866 ## Solution - Simply migrate where possible. ## Testing - Expect that CI will do most of the work. Examples is another way of testing this, as most of the work is in that area. --- ## Notes For now, this PR doesn't migrate `QueryState::single` and friends as for now, this look like another issue. So for example, QueryBuilders that used single or `World::query` that used single wasn't migrated. If there is a easy way to migrate those, please let me know. Most of the uses of `Query::single` were removed, the only other uses that I found was related to tests of said methods, so will probably be removed when we remove `Query::single`. |
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Joona Aalto
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25bfa80e60
|
Migrate cameras to required components (#15641)
# Objective Yet another PR for migrating stuff to required components. This time, cameras! ## Solution As per the [selected proposal](https://hackmd.io/tsYID4CGRiWxzsgawzxG_g#Combined-Proposal-1-Selected), deprecate `Camera2dBundle` and `Camera3dBundle` in favor of `Camera2d` and `Camera3d`. Adding a `Camera` without `Camera2d` or `Camera3d` now logs a warning, as suggested by Cart [on Discord](https://discord.com/channels/691052431525675048/1264881140007702558/1291506402832945273). I would personally like cameras to work a bit differently and be split into a few more components, to avoid some footguns and confusing semantics, but that is more controversial, and shouldn't block this core migration. ## Testing I ran a few 2D and 3D examples, and tried cameras with and without render graphs. --- ## Migration Guide `Camera2dBundle` and `Camera3dBundle` have been deprecated in favor of `Camera2d` and `Camera3d`. Inserting them will now also insert the other components required by them automatically. |
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Joona Aalto
|
54006b107b
|
Migrate meshes and materials to required components (#15524)
# Objective A big step in the migration to required components: meshes and materials! ## Solution As per the [selected proposal](https://hackmd.io/@bevy/required_components/%2Fj9-PnF-2QKK0on1KQ29UWQ): - Deprecate `MaterialMesh2dBundle`, `MaterialMeshBundle`, and `PbrBundle`. - Add `Mesh2d` and `Mesh3d` components, which wrap a `Handle<Mesh>`. - Add `MeshMaterial2d<M: Material2d>` and `MeshMaterial3d<M: Material>`, which wrap a `Handle<M>`. - Meshes *without* a mesh material should be rendered with a default material. The existence of a material is determined by `HasMaterial2d`/`HasMaterial3d`, which is required by `MeshMaterial2d`/`MeshMaterial3d`. This gets around problems with the generics. Previously: ```rust commands.spawn(MaterialMesh2dBundle { mesh: meshes.add(Circle::new(100.0)).into(), material: materials.add(Color::srgb(7.5, 0.0, 7.5)), transform: Transform::from_translation(Vec3::new(-200., 0., 0.)), ..default() }); ``` Now: ```rust commands.spawn(( Mesh2d(meshes.add(Circle::new(100.0))), MeshMaterial2d(materials.add(Color::srgb(7.5, 0.0, 7.5))), Transform::from_translation(Vec3::new(-200., 0., 0.)), )); ``` If the mesh material is missing, previously nothing was rendered. Now, it renders a white default `ColorMaterial` in 2D and a `StandardMaterial` in 3D (this can be overridden). Below, only every other entity has a material:   Why white? This is still open for discussion, but I think white makes sense for a *default* material, while *invalid* asset handles pointing to nothing should have something like a pink material to indicate that something is broken (I don't handle that in this PR yet). This is kind of a mix of Godot and Unity: Godot just renders a white material for non-existent materials, while Unity renders nothing when no materials exist, but renders pink for invalid materials. I can also change the default material to pink if that is preferable though. ## Testing I ran some 2D and 3D examples to test if anything changed visually. I have not tested all examples or features yet however. If anyone wants to test more extensively, it would be appreciated! ## Implementation Notes - The relationship between `bevy_render` and `bevy_pbr` is weird here. `bevy_render` needs `Mesh3d` for its own systems, but `bevy_pbr` has all of the material logic, and `bevy_render` doesn't depend on it. I feel like the two crates should be refactored in some way, but I think that's out of scope for this PR. - I didn't migrate meshlets to required components yet. That can probably be done in a follow-up, as this is already a huge PR. - It is becoming increasingly clear to me that we really, *really* want to disallow raw asset handles as components. They caused me a *ton* of headache here already, and it took me a long time to find every place that queried for them or inserted them directly on entities, since there were no compiler errors for it. If we don't remove the `Component` derive, I expect raw asset handles to be a *huge* footgun for users as we transition to wrapper components, especially as handles as components have been the norm so far. I personally consider this to be a blocker for 0.15: we need to migrate to wrapper components for asset handles everywhere, and remove the `Component` derive. Also see https://github.com/bevyengine/bevy/issues/14124. --- ## Migration Guide Asset handles for meshes and mesh materials must now be wrapped in the `Mesh2d` and `MeshMaterial2d` or `Mesh3d` and `MeshMaterial3d` components for 2D and 3D respectively. Raw handles as components no longer render meshes. Additionally, `MaterialMesh2dBundle`, `MaterialMeshBundle`, and `PbrBundle` have been deprecated. Instead, use the mesh and material components directly. Previously: ```rust commands.spawn(MaterialMesh2dBundle { mesh: meshes.add(Circle::new(100.0)).into(), material: materials.add(Color::srgb(7.5, 0.0, 7.5)), transform: Transform::from_translation(Vec3::new(-200., 0., 0.)), ..default() }); ``` Now: ```rust commands.spawn(( Mesh2d(meshes.add(Circle::new(100.0))), MeshMaterial2d(materials.add(Color::srgb(7.5, 0.0, 7.5))), Transform::from_translation(Vec3::new(-200., 0., 0.)), )); ``` If the mesh material is missing, a white default material is now used. Previously, nothing was rendered if the material was missing. The `WithMesh2d` and `WithMesh3d` query filter type aliases have also been removed. Simply use `With<Mesh2d>` or `With<Mesh3d>`. --------- Co-authored-by: Tim Blackbird <justthecooldude@gmail.com> Co-authored-by: Carter Anderson <mcanders1@gmail.com> |
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|
Joona Aalto
|
de888a373d
|
Migrate lights to required components (#15554)
# Objective Another step in the migration to required components: lights! Note that this does not include `EnvironmentMapLight` or reflection probes yet, because their API hasn't been fully chosen yet. ## Solution As per the [selected proposals](https://hackmd.io/@bevy/required_components/%2FLLnzwz9XTxiD7i2jiUXkJg): - Deprecate `PointLightBundle` in favor of the `PointLight` component - Deprecate `SpotLightBundle` in favor of the `PointLight` component - Deprecate `DirectionalLightBundle` in favor of the `DirectionalLight` component ## Testing I ran some examples with lights. --- ## Migration Guide `PointLightBundle`, `SpotLightBundle`, and `DirectionalLightBundle` have been deprecated. Use the `PointLight`, `SpotLight`, and `DirectionalLight` components instead. Adding them will now insert the other components required by them automatically. |
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Kornel
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435d9bc02c
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Highlight dependency on shader files in examples (#13824)
The examples won't work when copy-pasted to another project, without also copying their shader files. This change adds constants at the top of the files to bring attention to the dependencies. Follow up to [#13624](https://github.com/bevyengine/bevy/pull/13624#issuecomment-2143872791) |
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Alice Cecile
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599e5e4e76
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Migrate from LegacyColor to bevy_color::Color (#12163)
# Objective - As part of the migration process we need to a) see the end effect of the migration on user ergonomics b) check for serious perf regressions c) actually migrate the code - To accomplish this, I'm going to attempt to migrate all of the remaining user-facing usages of `LegacyColor` in one PR, being careful to keep a clean commit history. - Fixes #12056. ## Solution I've chosen to use the polymorphic `Color` type as our standard user-facing API. - [x] Migrate `bevy_gizmos`. - [x] Take `impl Into<Color>` in all `bevy_gizmos` APIs - [x] Migrate sprites - [x] Migrate UI - [x] Migrate `ColorMaterial` - [x] Migrate `MaterialMesh2D` - [x] Migrate fog - [x] Migrate lights - [x] Migrate StandardMaterial - [x] Migrate wireframes - [x] Migrate clear color - [x] Migrate text - [x] Migrate gltf loader - [x] Register color types for reflection - [x] Remove `LegacyColor` - [x] Make sure CI passes Incidental improvements to ease migration: - added `Color::srgba_u8`, `Color::srgba_from_array` and friends - added `set_alpha`, `is_fully_transparent` and `is_fully_opaque` to the `Alpha` trait - add and immediately deprecate (lol) `Color::rgb` and friends in favor of more explicit and consistent `Color::srgb` - standardized on white and black for most example text colors - added vector field traits to `LinearRgba`: ~~`Add`, `Sub`, `AddAssign`, `SubAssign`,~~ `Mul<f32>` and `Div<f32>`. Multiplications and divisions do not scale alpha. `Add` and `Sub` have been cut from this PR. - added `LinearRgba` and `Srgba` `RED/GREEN/BLUE` - added `LinearRgba_to_f32_array` and `LinearRgba::to_u32` ## Migration Guide Bevy's color types have changed! Wherever you used a `bevy::render::Color`, a `bevy::color::Color` is used instead. These are quite similar! Both are enums storing a color in a specific color space (or to be more precise, using a specific color model). However, each of the different color models now has its own type. TODO... - `Color::rgba`, `Color::rgb`, `Color::rbga_u8`, `Color::rgb_u8`, `Color::rgb_from_array` are now `Color::srgba`, `Color::srgb`, `Color::srgba_u8`, `Color::srgb_u8` and `Color::srgb_from_array`. - `Color::set_a` and `Color::a` is now `Color::set_alpha` and `Color::alpha`. These are part of the `Alpha` trait in `bevy_color`. - `Color::is_fully_transparent` is now part of the `Alpha` trait in `bevy_color` - `Color::r`, `Color::set_r`, `Color::with_r` and the equivalents for `g`, `b` `h`, `s` and `l` have been removed due to causing silent relatively expensive conversions. Convert your `Color` into the desired color space, perform your operations there, and then convert it back into a polymorphic `Color` enum. - `Color::hex` is now `Srgba::hex`. Call `.into` or construct a `Color::Srgba` variant manually to convert it. - `WireframeMaterial`, `ExtractedUiNode`, `ExtractedDirectionalLight`, `ExtractedPointLight`, `ExtractedSpotLight` and `ExtractedSprite` now store a `LinearRgba`, rather than a polymorphic `Color` - `Color::rgb_linear` and `Color::rgba_linear` are now `Color::linear_rgb` and `Color::linear_rgba` - The various CSS color constants are no longer stored directly on `Color`. Instead, they're defined in the `Srgba` color space, and accessed via `bevy::color::palettes::css`. Call `.into()` on them to convert them into a `Color` for quick debugging use, and consider using the much prettier `tailwind` palette for prototyping. - The `LIME_GREEN` color has been renamed to `LIMEGREEN` to comply with the standard naming. - Vector field arithmetic operations on `Color` (add, subtract, multiply and divide by a f32) have been removed. Instead, convert your colors into `LinearRgba` space, and perform your operations explicitly there. This is particularly relevant when working with emissive or HDR colors, whose color channel values are routinely outside of the ordinary 0 to 1 range. - `Color::as_linear_rgba_f32` has been removed. Call `LinearRgba::to_f32_array` instead, converting if needed. - `Color::as_linear_rgba_u32` has been removed. Call `LinearRgba::to_u32` instead, converting if needed. - Several other color conversion methods to transform LCH or HSL colors into float arrays or `Vec` types have been removed. Please reimplement these externally or open a PR to re-add them if you found them particularly useful. - Various methods on `Color` such as `rgb` or `hsl` to convert the color into a specific color space have been removed. Convert into `LinearRgba`, then to the color space of your choice. - Various implicitly-converting color value methods on `Color` such as `r`, `g`, `b` or `h` have been removed. Please convert it into the color space of your choice, then check these properties. - `Color` no longer implements `AsBindGroup`. Store a `LinearRgba` internally instead to avoid conversion costs. --------- Co-authored-by: Alice Cecile <alice.i.cecil@gmail.com> Co-authored-by: Afonso Lage <lage.afonso@gmail.com> Co-authored-by: Rob Parrett <robparrett@gmail.com> Co-authored-by: Zachary Harrold <zac@harrold.com.au> |
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Alice Cecile
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de004da8d5
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Rename bevy_render::Color to LegacyColor (#12069)
# Objective The migration process for `bevy_color` (#12013) will be fairly involved: there will be hundreds of affected files, and a large number of APIs. ## Solution To allow us to proceed granularly, we're going to keep both `bevy_color::Color` (new) and `bevy_render::Color` (old) around until the migration is complete. However, simply doing this directly is confusing! They're both called `Color`, making it very hard to tell when a portion of the code has been ported. As discussed in #12056, by renaming the old `Color` type, we can make it easier to gradually migrate over, one API at a time. ## Migration Guide THIS MIGRATION GUIDE INTENTIONALLY LEFT BLANK. This change should not be shipped to end users: delete this section in the final migration guide! --------- Co-authored-by: Alice Cecile <alice.i.cecil@gmail.com> |
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Carter Anderson
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dd619a1087
|
New Exposure and Lighting Defaults (and calibrate examples) (#11868)
# Objective After adding configurable exposure, we set the default ev100 value to `7` (indoor). This brought us out of sync with Blender's configuration and defaults. This PR changes the default to `9.7` (bright indoor or very overcast outdoors), as I calibrated in #11577. This feels like a very reasonable default. The other changes generally center around tweaking Bevy's lighting defaults and examples to play nicely with this number, alongside a few other tweaks and improvements. Note that for artistic reasons I have reverted some examples, which changed to directional lights in #11581, back to point lights. Fixes #11577 --- ## Changelog - Changed `Exposure::ev100` from `7` to `9.7` to better match Blender - Renamed `ExposureSettings` to `Exposure` - `Camera3dBundle` now includes `Exposure` for discoverability - Bumped `FULL_DAYLIGHT ` and `DIRECT_SUNLIGHT` to represent the middle-to-top of those ranges instead of near the bottom - Added new `AMBIENT_DAYLIGHT` constant and set that as the new `DirectionalLight` default illuminance. - `PointLight` and `SpotLight` now have a default `intensity` of 1,000,000 lumens. This makes them actually useful in the context of the new "semi-outdoor" exposure and puts them in the "cinema lighting" category instead of the "common household light" category. They are also reasonably close to the Blender default. - `AmbientLight` default has been bumped from `20` to `80`. ## Migration Guide - The increased `Exposure::ev100` means that all existing 3D lighting will need to be adjusted to match (DirectionalLights, PointLights, SpotLights, EnvironmentMapLights, etc). Or alternatively, you can adjust the `Exposure::ev100` on your cameras to work nicely with your current lighting values. If you are currently relying on default intensity values, you might need to change the intensity to achieve the same effect. Note that in Bevy 0.12, point/spot lights had a different hard coded ev100 value than directional lights. In Bevy 0.13, they use the same ev100, so if you have both in your scene, the _scale_ between these light types has changed and you will likely need to adjust one or both of them. |
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Doonv
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dc9b486650
|
Change light defaults & fix light examples (#11581)
# Objective Fix https://github.com/bevyengine/bevy/issues/11577. ## Solution Fix the examples, add a few constants to make setting light values easier, and change the default lighting settings to be more realistic. (Now designed for an overcast day instead of an indoor environment) --- I did not include any example-related changes in here. ## Changelogs (not including breaking changes) ### bevy_pbr - Added `light_consts` module (included in prelude), which contains common lux and lumen values for lights. - Added `AmbientLight::NONE` constant, which is an ambient light with a brightness of 0. - Added non-EV100 variants for `ExposureSettings`'s EV100 constants, which allow easier construction of an `ExposureSettings` from a EV100 constant. ## Breaking changes ### bevy_pbr The several default lighting values were changed: - `PointLight`'s default `intensity` is now `2000.0` - `SpotLight`'s default `intensity` is now `2000.0` - `DirectionalLight`'s default `illuminance` is now `light_consts::lux::OVERCAST_DAY` (`1000.`) - `AmbientLight`'s default `brightness` is now `20.0` |
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Joona Aalto
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0166db33f7
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Deprecate shapes in bevy_render::mesh::shape (#11773)
# Objective #11431 and #11688 implemented meshing support for Bevy's new geometric primitives. The next step is to deprecate the shapes in `bevy_render::mesh::shape` and to later remove them completely for 0.14. ## Solution Deprecate the shapes and reduce code duplication by utilizing the primitive meshing API for the old shapes where possible. Note that some shapes have behavior that can't be exactly reproduced with the new primitives yet: - `Box` is more of an AABB with min/max extents - `Plane` supports a subdivision count - `Quad` has a `flipped` property These types have not been changed to utilize the new primitives yet. --- ## Changelog - Deprecated all shapes in `bevy_render::mesh::shape` - Changed all examples to use new primitives for meshing ## Migration Guide Bevy has previously used rendering-specific types like `UVSphere` and `Quad` for primitive mesh shapes. These have now been deprecated to use the geometric primitives newly introduced in version 0.13. Some examples: ```rust let before = meshes.add(shape::Box::new(5.0, 0.15, 5.0)); let after = meshes.add(Cuboid::new(5.0, 0.15, 5.0)); let before = meshes.add(shape::Quad::default()); let after = meshes.add(Rectangle::default()); let before = meshes.add(shape::Plane::from_size(5.0)); // The surface normal can now also be specified when using `new` let after = meshes.add(Plane3d::default().mesh().size(5.0, 5.0)); let before = meshes.add( Mesh::try_from(shape::Icosphere { radius: 0.5, subdivisions: 5, }) .unwrap(), ); let after = meshes.add(Sphere::new(0.5).mesh().ico(5).unwrap()); ``` |
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Tristan Guichaoua
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694c06f3d0
|
Inverse missing_docs logic (#11676)
# Objective Currently the `missing_docs` lint is allowed-by-default and enabled at crate level when their documentations is complete (see #3492). This PR proposes to inverse this logic by making `missing_docs` warn-by-default and mark crates with imcomplete docs allowed. ## Solution Makes `missing_docs` warn at workspace level and allowed at crate level when the docs is imcomplete. |
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JMS55
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fcd7c0fc3d
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Exposure settings (adopted) (#11347)
Rebased and finished version of https://github.com/bevyengine/bevy/pull/8407. Huge thanks to @GitGhillie for adjusting all the examples, and the many other people who helped write this PR (@superdump , @coreh , among others) :) Fixes https://github.com/bevyengine/bevy/issues/8369 --- ## Changelog - Added a `brightness` control to `Skybox`. - Added an `intensity` control to `EnvironmentMapLight`. - Added `ExposureSettings` and `PhysicalCameraParameters` for controlling exposure of 3D cameras. - Removed the baked-in `DirectionalLight` exposure Bevy previously hardcoded internally. ## Migration Guide - If using a `Skybox` or `EnvironmentMapLight`, use the new `brightness` and `intensity` controls to adjust their strength. - All 3D scene will now have different apparent brightnesses due to Bevy implementing proper exposure controls. You will have to adjust the intensity of your lights and/or your camera exposure via the new `ExposureSettings` component to compensate. --------- Co-authored-by: Robert Swain <robert.swain@gmail.com> Co-authored-by: GitGhillie <jillisnoordhoek@gmail.com> Co-authored-by: Marco Buono <thecoreh@gmail.com> Co-authored-by: vero <email@atlasdostal.com> Co-authored-by: atlas dostal <rodol@rivalrebels.com> |
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Joona Aalto
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a795de30b4
|
Use impl Into<A> for Assets::add (#10878)
# Motivation
When spawning entities into a scene, it is very common to create assets
like meshes and materials and to add them via asset handles. A common
setup might look like this:
```rust
fn setup(
mut commands: Commands,
mut meshes: ResMut<Assets<Mesh>>,
mut materials: ResMut<Assets<StandardMaterial>>,
) {
commands.spawn(PbrBundle {
mesh: meshes.add(Mesh::from(shape::Cube { size: 1.0 })),
material: materials.add(StandardMaterial::from(Color::RED)),
..default()
});
}
```
Let's take a closer look at the part that adds the assets using `add`.
```rust
mesh: meshes.add(Mesh::from(shape::Cube { size: 1.0 })),
material: materials.add(StandardMaterial::from(Color::RED)),
```
Here, "mesh" and "material" are both repeated three times. It's very
explicit, but I find it to be a bit verbose. In addition to being more
code to read and write, the extra characters can sometimes also lead to
the code being formatted to span multiple lines even though the core
task, adding e.g. a primitive mesh, is extremely simple.
A way to address this is by using `.into()`:
```rust
mesh: meshes.add(shape::Cube { size: 1.0 }.into()),
material: materials.add(Color::RED.into()),
```
This is fine, but from the names and the type of `meshes`, we already
know what the type should be. It's very clear that `Cube` should be
turned into a `Mesh` because of the context it's used in. `.into()` is
just seven characters, but it's so common that it quickly adds up and
gets annoying.
It would be nice if you could skip all of the conversion and let Bevy
handle it for you:
```rust
mesh: meshes.add(shape::Cube { size: 1.0 }),
material: materials.add(Color::RED),
```
# Objective
Make adding assets more ergonomic by making `Assets::add` take an `impl
Into<A>` instead of `A`.
## Solution
`Assets::add` now takes an `impl Into<A>` instead of `A`, so e.g. this
works:
```rust
commands.spawn(PbrBundle {
mesh: meshes.add(shape::Cube { size: 1.0 }),
material: materials.add(Color::RED),
..default()
});
```
I also changed all examples to use this API, which increases consistency
as well because `Mesh::from` and `into` were being used arbitrarily even
in the same file. This also gets rid of some lines of code because
formatting is nicer.
---
## Changelog
- `Assets::add` now takes an `impl Into<A>` instead of `A`
- Examples don't use `T::from(K)` or `K.into()` when adding assets
## Migration Guide
Some `into` calls that worked previously might now be broken because of
the new trait bounds. You need to either remove `into` or perform the
conversion explicitly with `from`:
```rust
// Doesn't compile
let mesh_handle = meshes.add(shape::Cube { size: 1.0 }.into()),
// These compile
let mesh_handle = meshes.add(shape::Cube { size: 1.0 }),
let mesh_handle = meshes.add(Mesh::from(shape::Cube { size: 1.0 })),
```
## Concerns
I believe the primary concerns might be:
1. Is this too implicit?
2. Does this increase codegen bloat?
Previously, the two APIs were using `into` or `from`, and now it's
"nothing" or `from`. You could argue that `into` is slightly more
explicit than "nothing" in cases like the earlier examples where a
`Color` gets converted to e.g. a `StandardMaterial`, but I personally
don't think `into` adds much value even in this case, and you could
still see the actual type from the asset type.
As for codegen bloat, I doubt it adds that much, but I'm not very
familiar with the details of codegen. I personally value the user-facing
code reduction and ergonomics improvements that these changes would
provide, but it might be worth checking the other effects in more
detail.
Another slight concern is migration pain; apps might have a ton of
`into` calls that would need to be removed, and it did take me a while
to do so for Bevy itself (maybe around 20-40 minutes). However, I think
the fact that there *are* so many `into` calls just highlights that the
API could be made nicer, and I'd gladly migrate my own projects for it.
|
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Carter Anderson
|
5eb292dc10
|
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> |
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Edgar Geier
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f18f28874a
|
Allow tuples and single plugins in add_plugins, deprecate add_plugin (#8097)
# Objective - Better consistency with `add_systems`. - Deprecating `add_plugin` in favor of a more powerful `add_plugins`. - Allow passing `Plugin` to `add_plugins`. - Allow passing tuples to `add_plugins`. ## Solution - `App::add_plugins` now takes an `impl Plugins` parameter. - `App::add_plugin` is deprecated. - `Plugins` is a new sealed trait that is only implemented for `Plugin`, `PluginGroup` and tuples over `Plugins`. - All examples, benchmarks and tests are changed to use `add_plugins`, using tuples where appropriate. --- ## Changelog ### Changed - `App::add_plugins` now accepts all types that implement `Plugins`, which is implemented for: - Types that implement `Plugin`. - Types that implement `PluginGroup`. - Tuples (up to 16 elements) over types that implement `Plugins`. - Deprecated `App::add_plugin` in favor of `App::add_plugins`. ## Migration Guide - Replace `app.add_plugin(plugin)` calls with `app.add_plugins(plugin)`. --------- Co-authored-by: Carter Anderson <mcanders1@gmail.com> |
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radiish
|
1efc762924
|
reflect: stable type path v2 (#7184)
# Objective
- Introduce a stable alternative to
[`std::any::type_name`](https://doc.rust-lang.org/std/any/fn.type_name.html).
- Rewrite of #5805 with heavy inspiration in design.
- On the path to #5830.
- Part of solving #3327.
## Solution
- Add a `TypePath` trait for static stable type path/name information.
- Add a `TypePath` derive macro.
- Add a `impl_type_path` macro for implementing internal and foreign
types in `bevy_reflect`.
---
## Changelog
- Added `TypePath` trait.
- Added `DynamicTypePath` trait and `get_type_path` method to `Reflect`.
- Added a `TypePath` derive macro.
- Added a `bevy_reflect::impl_type_path` for implementing `TypePath` on
internal and foreign types in `bevy_reflect`.
- Changed `bevy_reflect::utility::(Non)GenericTypeInfoCell` to
`(Non)GenericTypedCell<T>` which allows us to be generic over both
`TypeInfo` and `TypePath`.
- `TypePath` is now a supertrait of `Asset`, `Material` and
`Material2d`.
- `impl_reflect_struct` needs a `#[type_path = "..."]` attribute to be
specified.
- `impl_reflect_value` needs to either specify path starting with a
double colon (`::core::option::Option`) or an `in my_crate::foo`
declaration.
- Added `bevy_reflect_derive::ReflectTypePath`.
- Most uses of `Ident` in `bevy_reflect_derive` changed to use
`ReflectTypePath`.
## Migration Guide
- Implementors of `Asset`, `Material` and `Material2d` now also need to
derive `TypePath`.
- Manual implementors of `Reflect` will need to implement the new
`get_type_path` method.
## Open Questions
- [x] ~This PR currently does not migrate any usages of
`std::any::type_name` to use `bevy_reflect::TypePath` to ease the review
process. Should it?~ Migration will be left to a follow-up PR.
- [ ] This PR adds a lot of `#[derive(TypePath)]` and `T: TypePath` to
satisfy new bounds, mostly when deriving `TypeUuid`. Should we make
`TypePath` a supertrait of `TypeUuid`? [Should we remove `TypeUuid` in
favour of
`TypePath`?](
|
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Carter Anderson
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aefe1f0739
|
Schedule-First: the new and improved add_systems (#8079)
Co-authored-by: Mike <mike.hsu@gmail.com> |
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JoJoJet
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fd1af7c8b8
|
Replace multiple calls to add_system with add_systems (#8001)
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woodroww
|
1bd390806f |
added subdivisions to shape::Plane (#7546)
# Objective There was issue #191 requesting subdivisions on the shape::Plane. I also could have used this recently. I then write the solution. Fixes #191 ## Solution I changed the shape::Plane to include subdivisions field and the code to create the subdivisions. I don't know how people are counting subdivisions so as I put in the doc comments 0 subdivisions results in the original geometry of the Plane. Greater then 0 results in the number of lines dividing the plane. I didn't know if it would be better to create a new struct that implemented this feature, say SubdivisionPlane or change Plane. I decided on changing Plane as that was what the original issue was. It would be trivial to alter this to use another struct instead of altering Plane. The issues of migration, although small, would be eliminated if a new struct was implemented. ## Changelog ### Added Added subdivisions field to shape::Plane ## Migration Guide All the examples needed to be updated to initalize the subdivisions field. Also there were two tests in tests/window that need to be updated. A user would have to update all their uses of shape::Plane to initalize the subdivisions field. |
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Carter Anderson
|
dcc03724a5 |
Base Sets (#7466)
# Objective NOTE: This depends on #7267 and should not be merged until #7267 is merged. If you are reviewing this before that is merged, I highly recommend viewing the Base Sets commit instead of trying to find my changes amongst those from #7267. "Default sets" as described by the [Stageless RFC](https://github.com/bevyengine/rfcs/pull/45) have some [unfortunate consequences](https://github.com/bevyengine/bevy/discussions/7365). ## Solution This adds "base sets" as a variant of `SystemSet`: A set is a "base set" if `SystemSet::is_base` returns `true`. Typically this will be opted-in to using the `SystemSet` derive: ```rust #[derive(SystemSet, Clone, Hash, Debug, PartialEq, Eq)] #[system_set(base)] enum MyBaseSet { A, B, } ``` **Base sets are exclusive**: a system can belong to at most one "base set". Adding a system to more than one will result in an error. When possible we fail immediately during system-config-time with a nice file + line number. For the more nested graph-ey cases, this will fail at the final schedule build. **Base sets cannot belong to other sets**: this is where the word "base" comes from Systems and Sets can only be added to base sets using `in_base_set`. Calling `in_set` with a base set will fail. As will calling `in_base_set` with a normal set. ```rust app.add_system(foo.in_base_set(MyBaseSet::A)) // X must be a normal set ... base sets cannot be added to base sets .configure_set(X.in_base_set(MyBaseSet::A)) ``` Base sets can still be configured like normal sets: ```rust app.add_system(MyBaseSet::B.after(MyBaseSet::Ap)) ``` The primary use case for base sets is enabling a "default base set": ```rust schedule.set_default_base_set(CoreSet::Update) // this will belong to CoreSet::Update by default .add_system(foo) // this will override the default base set with PostUpdate .add_system(bar.in_base_set(CoreSet::PostUpdate)) ``` This allows us to build apis that work by default in the standard Bevy style. This is a rough analog to the "default stage" model, but it use the new "stageless sets" model instead, with all of the ordering flexibility (including exclusive systems) that it provides. --- ## Changelog - Added "base sets" and ported CoreSet to use them. ## Migration Guide TODO |
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|
Alice Cecile
|
206c7ce219 |
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. |
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|
Carter Anderson
|
01aedc8431 |
Spawn now takes a Bundle (#6054)
# Objective Now that we can consolidate Bundles and Components under a single insert (thanks to #2975 and #6039), almost 100% of world spawns now look like `world.spawn().insert((Some, Tuple, Here))`. Spawning an entity without any components is an extremely uncommon pattern, so it makes sense to give spawn the "first class" ergonomic api. This consolidated api should be made consistent across all spawn apis (such as World and Commands). ## Solution All `spawn` apis (`World::spawn`, `Commands:;spawn`, `ChildBuilder::spawn`, and `WorldChildBuilder::spawn`) now accept a bundle as input: ```rust // before: commands .spawn() .insert((A, B, C)); world .spawn() .insert((A, B, C); // after commands.spawn((A, B, C)); world.spawn((A, B, C)); ``` All existing instances of `spawn_bundle` have been deprecated in favor of the new `spawn` api. A new `spawn_empty` has been added, replacing the old `spawn` api. By allowing `world.spawn(some_bundle)` to replace `world.spawn().insert(some_bundle)`, this opened the door to removing the initial entity allocation in the "empty" archetype / table done in `spawn()` (and subsequent move to the actual archetype in `.insert(some_bundle)`). This improves spawn performance by over 10%:  To take this measurement, I added a new `world_spawn` benchmark. Unfortunately, optimizing `Commands::spawn` is slightly less trivial, as Commands expose the Entity id of spawned entities prior to actually spawning. Doing the optimization would (naively) require assurances that the `spawn(some_bundle)` command is applied before all other commands involving the entity (which would not necessarily be true, if memory serves). Optimizing `Commands::spawn` this way does feel possible, but it will require careful thought (and maybe some additional checks), which deserves its own PR. For now, it has the same performance characteristics of the current `Commands::spawn_bundle` on main. **Note that 99% of this PR is simple renames and refactors. The only code that needs careful scrutiny is the new `World::spawn()` impl, which is relatively straightforward, but it has some new unsafe code (which re-uses battle tested BundlerSpawner code path).** --- ## Changelog - All `spawn` apis (`World::spawn`, `Commands:;spawn`, `ChildBuilder::spawn`, and `WorldChildBuilder::spawn`) now accept a bundle as input - All instances of `spawn_bundle` have been deprecated in favor of the new `spawn` api - World and Commands now have `spawn_empty()`, which is equivalent to the old `spawn()` behavior. ## Migration Guide ```rust // Old (0.8): commands .spawn() .insert_bundle((A, B, C)); // New (0.9) commands.spawn((A, B, C)); // Old (0.8): commands.spawn_bundle((A, B, C)); // New (0.9) commands.spawn((A, B, C)); // Old (0.8): let entity = commands.spawn().id(); // New (0.9) let entity = commands.spawn_empty().id(); // Old (0.8) let entity = world.spawn().id(); // New (0.9) let entity = world.spawn_empty(); ``` |
||
|
Carter Anderson
|
cd15f0f5be |
Accept Bundles for insert and remove. Deprecate insert/remove_bundle (#6039)
# Objective Take advantage of the "impl Bundle for Component" changes in #2975 / add the follow up changes discussed there. ## Solution - Change `insert` and `remove` to accept a Bundle instead of a Component (for both Commands and World) - Deprecate `insert_bundle`, `remove_bundle`, and `remove_bundle_intersection` - Add `remove_intersection` --- ## Changelog - Change `insert` and `remove` now accept a Bundle instead of a Component (for both Commands and World) - `insert_bundle` and `remove_bundle` are deprecated ## Migration Guide Replace `insert_bundle` with `insert`: ```rust // Old (0.8) commands.spawn().insert_bundle(SomeBundle::default()); // New (0.9) commands.spawn().insert(SomeBundle::default()); ``` Replace `remove_bundle` with `remove`: ```rust // Old (0.8) commands.entity(some_entity).remove_bundle::<SomeBundle>(); // New (0.9) commands.entity(some_entity).remove::<SomeBundle>(); ``` Replace `remove_bundle_intersection` with `remove_intersection`: ```rust // Old (0.8) world.entity_mut(some_entity).remove_bundle_intersection::<SomeBundle>(); // New (0.9) world.entity_mut(some_entity).remove_intersection::<SomeBundle>(); ``` Consider consolidating as many operations as possible to improve ergonomics and cut down on archetype moves: ```rust // Old (0.8) commands.spawn() .insert_bundle(SomeBundle::default()) .insert(SomeComponent); // New (0.9) - Option 1 commands.spawn().insert(( SomeBundle::default(), SomeComponent, )) // New (0.9) - Option 2 commands.spawn_bundle(( SomeBundle::default(), SomeComponent, )) ``` ## Next Steps Consider changing `spawn` to accept a bundle and deprecate `spawn_bundle`. |
||
|
Carter Anderson
|
747b0c69b0 |
Better Materials: AsBindGroup trait and derive, simpler Material trait (#5053)
# Objective
This PR reworks Bevy's Material system, making the user experience of defining Materials _much_ nicer. Bevy's previous material system leaves a lot to be desired:
* Materials require manually implementing the `RenderAsset` trait, which involves manually generating the bind group, handling gpu buffer data transfer, looking up image textures, etc. Even the simplest single-texture material involves writing ~80 unnecessary lines of code. This was never the long term plan.
* There are two material traits, which is confusing, hard to document, and often redundant: `Material` and `SpecializedMaterial`. `Material` implicitly implements `SpecializedMaterial`, and `SpecializedMaterial` is used in most high level apis to support both use cases. Most users shouldn't need to think about specialization at all (I consider it a "power-user tool"), so the fact that `SpecializedMaterial` is front-and-center in our apis is a miss.
* Implementing either material trait involves a lot of "type soup". The "prepared asset" parameter is particularly heinous: `&<Self as RenderAsset>::PreparedAsset`. Defining vertex and fragment shaders is also more verbose than it needs to be.
## Solution
Say hello to the new `Material` system:
```rust
#[derive(AsBindGroup, TypeUuid, Debug, Clone)]
#[uuid = "f690fdae-d598-45ab-8225-97e2a3f056e0"]
pub struct CoolMaterial {
#[uniform(0)]
color: Color,
#[texture(1)]
#[sampler(2)]
color_texture: Handle<Image>,
}
impl Material for CoolMaterial {
fn fragment_shader() -> ShaderRef {
"cool_material.wgsl".into()
}
}
```
Thats it! This same material would have required [~80 lines of complicated "type heavy" code](https://github.com/bevyengine/bevy/blob/v0.7.0/examples/shader/shader_material.rs) in the old Material system. Now it is just 14 lines of simple, readable code.
This is thanks to a new consolidated `Material` trait and the new `AsBindGroup` trait / derive.
### The new `Material` trait
The old "split" `Material` and `SpecializedMaterial` traits have been removed in favor of a new consolidated `Material` trait. All of the functions on the trait are optional.
The difficulty of implementing `Material` has been reduced by simplifying dataflow and removing type complexity:
```rust
// Old
impl Material for CustomMaterial {
fn fragment_shader(asset_server: &AssetServer) -> Option<Handle<Shader>> {
Some(asset_server.load("custom_material.wgsl"))
}
fn alpha_mode(render_asset: &<Self as RenderAsset>::PreparedAsset) -> AlphaMode {
render_asset.alpha_mode
}
}
// New
impl Material for CustomMaterial {
fn fragment_shader() -> ShaderRef {
"custom_material.wgsl".into()
}
fn alpha_mode(&self) -> AlphaMode {
self.alpha_mode
}
}
```
Specialization is still supported, but it is hidden by default under the `specialize()` function (more on this later).
### The `AsBindGroup` trait / derive
The `Material` trait now requires the `AsBindGroup` derive. This can be implemented manually relatively easily, but deriving it will almost always be preferable.
Field attributes like `uniform` and `texture` are used to define which fields should be bindings,
what their binding type is, and what index they should be bound at:
```rust
#[derive(AsBindGroup)]
struct CoolMaterial {
#[uniform(0)]
color: Color,
#[texture(1)]
#[sampler(2)]
color_texture: Handle<Image>,
}
```
In WGSL shaders, the binding looks like this:
```wgsl
struct CoolMaterial {
color: vec4<f32>;
};
[[group(1), binding(0)]]
var<uniform> material: CoolMaterial;
[[group(1), binding(1)]]
var color_texture: texture_2d<f32>;
[[group(1), binding(2)]]
var color_sampler: sampler;
```
Note that the "group" index is determined by the usage context. It is not defined in `AsBindGroup`. Bevy material bind groups are bound to group 1.
The following field-level attributes are supported:
* `uniform(BINDING_INDEX)`
* The field will be converted to a shader-compatible type using the `ShaderType` trait, written to a `Buffer`, and bound as a uniform. It can also be derived for custom structs.
* `texture(BINDING_INDEX)`
* This field's `Handle<Image>` will be used to look up the matching `Texture` gpu resource, which will be bound as a texture in shaders. The field will be assumed to implement `Into<Option<Handle<Image>>>`. In practice, most fields should be a `Handle<Image>` or `Option<Handle<Image>>`. If the value of an `Option<Handle<Image>>` is `None`, the new `FallbackImage` resource will be used instead. This attribute can be used in conjunction with a `sampler` binding attribute (with a different binding index).
* `sampler(BINDING_INDEX)`
* Behaves exactly like the `texture` attribute, but sets the Image's sampler binding instead of the texture.
Note that fields without field-level binding attributes will be ignored.
```rust
#[derive(AsBindGroup)]
struct CoolMaterial {
#[uniform(0)]
color: Color,
this_field_is_ignored: String,
}
```
As mentioned above, `Option<Handle<Image>>` is also supported:
```rust
#[derive(AsBindGroup)]
struct CoolMaterial {
#[uniform(0)]
color: Color,
#[texture(1)]
#[sampler(2)]
color_texture: Option<Handle<Image>>,
}
```
This is useful if you want a texture to be optional. When the value is `None`, the `FallbackImage` will be used for the binding instead, which defaults to "pure white".
Field uniforms with the same binding index will be combined into a single binding:
```rust
#[derive(AsBindGroup)]
struct CoolMaterial {
#[uniform(0)]
color: Color,
#[uniform(0)]
roughness: f32,
}
```
In WGSL shaders, the binding would look like this:
```wgsl
struct CoolMaterial {
color: vec4<f32>;
roughness: f32;
};
[[group(1), binding(0)]]
var<uniform> material: CoolMaterial;
```
Some less common scenarios will require "struct-level" attributes. These are the currently supported struct-level attributes:
* `uniform(BINDING_INDEX, ConvertedShaderType)`
* Similar to the field-level `uniform` attribute, but instead the entire `AsBindGroup` value is converted to `ConvertedShaderType`, which must implement `ShaderType`. This is useful if more complicated conversion logic is required.
* `bind_group_data(DataType)`
* The `AsBindGroup` type will be converted to some `DataType` using `Into<DataType>` and stored as `AsBindGroup::Data` as part of the `AsBindGroup::as_bind_group` call. This is useful if data needs to be stored alongside the generated bind group, such as a unique identifier for a material's bind group. The most common use case for this attribute is "shader pipeline specialization".
The previous `CoolMaterial` example illustrating "combining multiple field-level uniform attributes with the same binding index" can
also be equivalently represented with a single struct-level uniform attribute:
```rust
#[derive(AsBindGroup)]
#[uniform(0, CoolMaterialUniform)]
struct CoolMaterial {
color: Color,
roughness: f32,
}
#[derive(ShaderType)]
struct CoolMaterialUniform {
color: Color,
roughness: f32,
}
impl From<&CoolMaterial> for CoolMaterialUniform {
fn from(material: &CoolMaterial) -> CoolMaterialUniform {
CoolMaterialUniform {
color: material.color,
roughness: material.roughness,
}
}
}
```
### Material Specialization
Material shader specialization is now _much_ simpler:
```rust
#[derive(AsBindGroup, TypeUuid, Debug, Clone)]
#[uuid = "f690fdae-d598-45ab-8225-97e2a3f056e0"]
#[bind_group_data(CoolMaterialKey)]
struct CoolMaterial {
#[uniform(0)]
color: Color,
is_red: bool,
}
#[derive(Copy, Clone, Hash, Eq, PartialEq)]
struct CoolMaterialKey {
is_red: bool,
}
impl From<&CoolMaterial> for CoolMaterialKey {
fn from(material: &CoolMaterial) -> CoolMaterialKey {
CoolMaterialKey {
is_red: material.is_red,
}
}
}
impl Material for CoolMaterial {
fn fragment_shader() -> ShaderRef {
"cool_material.wgsl".into()
}
fn specialize(
pipeline: &MaterialPipeline<Self>,
descriptor: &mut RenderPipelineDescriptor,
layout: &MeshVertexBufferLayout,
key: MaterialPipelineKey<Self>,
) -> Result<(), SpecializedMeshPipelineError> {
if key.bind_group_data.is_red {
let fragment = descriptor.fragment.as_mut().unwrap();
fragment.shader_defs.push("IS_RED".to_string());
}
Ok(())
}
}
```
Setting `bind_group_data` is not required for specialization (it defaults to `()`). Scenarios like "custom vertex attributes" also benefit from this system:
```rust
impl Material for CustomMaterial {
fn vertex_shader() -> ShaderRef {
"custom_material.wgsl".into()
}
fn fragment_shader() -> ShaderRef {
"custom_material.wgsl".into()
}
fn specialize(
pipeline: &MaterialPipeline<Self>,
descriptor: &mut RenderPipelineDescriptor,
layout: &MeshVertexBufferLayout,
key: MaterialPipelineKey<Self>,
) -> Result<(), SpecializedMeshPipelineError> {
let vertex_layout = layout.get_layout(&[
Mesh::ATTRIBUTE_POSITION.at_shader_location(0),
ATTRIBUTE_BLEND_COLOR.at_shader_location(1),
])?;
descriptor.vertex.buffers = vec![vertex_layout];
Ok(())
}
}
```
### Ported `StandardMaterial` to the new `Material` system
Bevy's built-in PBR material uses the new Material system (including the AsBindGroup derive):
```rust
#[derive(AsBindGroup, Debug, Clone, TypeUuid)]
#[uuid = "7494888b-c082-457b-aacf-517228cc0c22"]
#[bind_group_data(StandardMaterialKey)]
#[uniform(0, StandardMaterialUniform)]
pub struct StandardMaterial {
pub base_color: Color,
#[texture(1)]
#[sampler(2)]
pub base_color_texture: Option<Handle<Image>>,
/* other fields omitted for brevity */
```
### Ported Bevy examples to the new `Material` system
The overall complexity of Bevy's "custom shader examples" has gone down significantly. Take a look at the diffs if you want a dopamine spike.
Please note that while this PR has a net increase in "lines of code", most of those extra lines come from added documentation. There is a significant reduction
in the overall complexity of the code (even accounting for the new derive logic).
---
## Changelog
### Added
* `AsBindGroup` trait and derive, which make it much easier to transfer data to the gpu and generate bind groups for a given type.
### Changed
* The old `Material` and `SpecializedMaterial` traits have been replaced by a consolidated (much simpler) `Material` trait. Materials no longer implement `RenderAsset`.
* `StandardMaterial` was ported to the new material system. There are no user-facing api changes to the `StandardMaterial` struct api, but it now implements `AsBindGroup` and `Material` instead of `RenderAsset` and `SpecializedMaterial`.
## Migration Guide
The Material system has been reworked to be much simpler. We've removed a lot of boilerplate with the new `AsBindGroup` derive and the `Material` trait is simpler as well!
### Bevy 0.7 (old)
```rust
#[derive(Debug, Clone, TypeUuid)]
#[uuid = "f690fdae-d598-45ab-8225-97e2a3f056e0"]
pub struct CustomMaterial {
color: Color,
color_texture: Handle<Image>,
}
#[derive(Clone)]
pub struct GpuCustomMaterial {
_buffer: Buffer,
bind_group: BindGroup,
}
impl RenderAsset for CustomMaterial {
type ExtractedAsset = CustomMaterial;
type PreparedAsset = GpuCustomMaterial;
type Param = (SRes<RenderDevice>, SRes<MaterialPipeline<Self>>);
fn extract_asset(&self) -> Self::ExtractedAsset {
self.clone()
}
fn prepare_asset(
extracted_asset: Self::ExtractedAsset,
(render_device, material_pipeline): &mut SystemParamItem<Self::Param>,
) -> Result<Self::PreparedAsset, PrepareAssetError<Self::ExtractedAsset>> {
let color = Vec4::from_slice(&extracted_asset.color.as_linear_rgba_f32());
let byte_buffer = [0u8; Vec4::SIZE.get() as usize];
let mut buffer = encase::UniformBuffer::new(byte_buffer);
buffer.write(&color).unwrap();
let buffer = render_device.create_buffer_with_data(&BufferInitDescriptor {
contents: buffer.as_ref(),
label: None,
usage: BufferUsages::UNIFORM | BufferUsages::COPY_DST,
});
let (texture_view, texture_sampler) = if let Some(result) = material_pipeline
.mesh_pipeline
.get_image_texture(gpu_images, &Some(extracted_asset.color_texture.clone()))
{
result
} else {
return Err(PrepareAssetError::RetryNextUpdate(extracted_asset));
};
let bind_group = render_device.create_bind_group(&BindGroupDescriptor {
entries: &[
BindGroupEntry {
binding: 0,
resource: buffer.as_entire_binding(),
},
BindGroupEntry {
binding: 0,
resource: BindingResource::TextureView(texture_view),
},
BindGroupEntry {
binding: 1,
resource: BindingResource::Sampler(texture_sampler),
},
],
label: None,
layout: &material_pipeline.material_layout,
});
Ok(GpuCustomMaterial {
_buffer: buffer,
bind_group,
})
}
}
impl Material for CustomMaterial {
fn fragment_shader(asset_server: &AssetServer) -> Option<Handle<Shader>> {
Some(asset_server.load("custom_material.wgsl"))
}
fn bind_group(render_asset: &<Self as RenderAsset>::PreparedAsset) -> &BindGroup {
&render_asset.bind_group
}
fn bind_group_layout(render_device: &RenderDevice) -> BindGroupLayout {
render_device.create_bind_group_layout(&BindGroupLayoutDescriptor {
entries: &[
BindGroupLayoutEntry {
binding: 0,
visibility: ShaderStages::FRAGMENT,
ty: BindingType::Buffer {
ty: BufferBindingType::Uniform,
has_dynamic_offset: false,
min_binding_size: Some(Vec4::min_size()),
},
count: None,
},
BindGroupLayoutEntry {
binding: 1,
visibility: ShaderStages::FRAGMENT,
ty: BindingType::Texture {
multisampled: false,
sample_type: TextureSampleType::Float { filterable: true },
view_dimension: TextureViewDimension::D2Array,
},
count: None,
},
BindGroupLayoutEntry {
binding: 2,
visibility: ShaderStages::FRAGMENT,
ty: BindingType::Sampler(SamplerBindingType::Filtering),
count: None,
},
],
label: None,
})
}
}
```
### Bevy 0.8 (new)
```rust
impl Material for CustomMaterial {
fn fragment_shader() -> ShaderRef {
"custom_material.wgsl".into()
}
}
#[derive(AsBindGroup, TypeUuid, Debug, Clone)]
#[uuid = "f690fdae-d598-45ab-8225-97e2a3f056e0"]
pub struct CustomMaterial {
#[uniform(0)]
color: Color,
#[texture(1)]
#[sampler(2)]
color_texture: Handle<Image>,
}
```
## Future Work
* Add support for more binding types (cubemaps, buffers, etc). This PR intentionally includes a bare minimum number of binding types to keep "reviewability" in check.
* Consider optionally eliding binding indices using binding names. `AsBindGroup` could pass in (optional?) reflection info as a "hint".
* This would make it possible for the derive to do this:
```rust
#[derive(AsBindGroup)]
pub struct CustomMaterial {
#[uniform]
color: Color,
#[texture]
#[sampler]
color_texture: Option<Handle<Image>>,
alpha_mode: AlphaMode,
}
```
* Or this
```rust
#[derive(AsBindGroup)]
pub struct CustomMaterial {
#[binding]
color: Color,
#[binding]
color_texture: Option<Handle<Image>>,
alpha_mode: AlphaMode,
}
```
* Or even this (if we flip to "include bindings by default")
```rust
#[derive(AsBindGroup)]
pub struct CustomMaterial {
color: Color,
color_texture: Option<Handle<Image>>,
#[binding(ignore)]
alpha_mode: AlphaMode,
}
```
* If we add the option to define custom draw functions for materials (which could be done in a type-erased way), I think that would be enough to support extra non-material bindings. Worth considering!
|
||
|
Carter Anderson
|
f487407e07 |
Camera Driven Rendering (#4745)
This adds "high level camera driven rendering" to Bevy. The goal is to give users more control over what gets rendered (and where) without needing to deal with render logic. This will make scenarios like "render to texture", "multiple windows", "split screen", "2d on 3d", "3d on 2d", "pass layering", and more significantly easier. Here is an [example of a 2d render sandwiched between two 3d renders (each from a different perspective)](https://gist.github.com/cart/4fe56874b2e53bc5594a182fc76f4915):  Users can now spawn a camera, point it at a RenderTarget (a texture or a window), and it will "just work". Rendering to a second window is as simple as spawning a second camera and assigning it to a specific window id: ```rust // main camera (main window) commands.spawn_bundle(Camera2dBundle::default()); // second camera (other window) commands.spawn_bundle(Camera2dBundle { camera: Camera { target: RenderTarget::Window(window_id), ..default() }, ..default() }); ``` Rendering to a texture is as simple as pointing the camera at a texture: ```rust commands.spawn_bundle(Camera2dBundle { camera: Camera { target: RenderTarget::Texture(image_handle), ..default() }, ..default() }); ``` Cameras now have a "render priority", which controls the order they are drawn in. If you want to use a camera's output texture as a texture in the main pass, just set the priority to a number lower than the main pass camera (which defaults to `0`). ```rust // main pass camera with a default priority of 0 commands.spawn_bundle(Camera2dBundle::default()); commands.spawn_bundle(Camera2dBundle { camera: Camera { target: RenderTarget::Texture(image_handle.clone()), priority: -1, ..default() }, ..default() }); commands.spawn_bundle(SpriteBundle { texture: image_handle, ..default() }) ``` Priority can also be used to layer to cameras on top of each other for the same RenderTarget. This is what "2d on top of 3d" looks like in the new system: ```rust commands.spawn_bundle(Camera3dBundle::default()); commands.spawn_bundle(Camera2dBundle { camera: Camera { // this will render 2d entities "on top" of the default 3d camera's render priority: 1, ..default() }, ..default() }); ``` There is no longer the concept of a global "active camera". Resources like `ActiveCamera<Camera2d>` and `ActiveCamera<Camera3d>` have been replaced with the camera-specific `Camera::is_active` field. This does put the onus on users to manage which cameras should be active. Cameras are now assigned a single render graph as an "entry point", which is configured on each camera entity using the new `CameraRenderGraph` component. The old `PerspectiveCameraBundle` and `OrthographicCameraBundle` (generic on camera marker components like Camera2d and Camera3d) have been replaced by `Camera3dBundle` and `Camera2dBundle`, which set 3d and 2d default values for the `CameraRenderGraph` and projections. ```rust // old 3d perspective camera commands.spawn_bundle(PerspectiveCameraBundle::default()) // new 3d perspective camera commands.spawn_bundle(Camera3dBundle::default()) ``` ```rust // old 2d orthographic camera commands.spawn_bundle(OrthographicCameraBundle::new_2d()) // new 2d orthographic camera commands.spawn_bundle(Camera2dBundle::default()) ``` ```rust // old 3d orthographic camera commands.spawn_bundle(OrthographicCameraBundle::new_3d()) // new 3d orthographic camera commands.spawn_bundle(Camera3dBundle { projection: OrthographicProjection { scale: 3.0, scaling_mode: ScalingMode::FixedVertical, ..default() }.into(), ..default() }) ``` Note that `Camera3dBundle` now uses a new `Projection` enum instead of hard coding the projection into the type. There are a number of motivators for this change: the render graph is now a part of the bundle, the way "generic bundles" work in the rust type system prevents nice `..default()` syntax, and changing projections at runtime is much easier with an enum (ex for editor scenarios). I'm open to discussing this choice, but I'm relatively certain we will all come to the same conclusion here. Camera2dBundle and Camera3dBundle are much clearer than being generic on marker components / using non-default constructors. If you want to run a custom render graph on a camera, just set the `CameraRenderGraph` component: ```rust commands.spawn_bundle(Camera3dBundle { camera_render_graph: CameraRenderGraph::new(some_render_graph_name), ..default() }) ``` Just note that if the graph requires data from specific components to work (such as `Camera3d` config, which is provided in the `Camera3dBundle`), make sure the relevant components have been added. Speaking of using components to configure graphs / passes, there are a number of new configuration options: ```rust commands.spawn_bundle(Camera3dBundle { camera_3d: Camera3d { // overrides the default global clear color clear_color: ClearColorConfig::Custom(Color::RED), ..default() }, ..default() }) commands.spawn_bundle(Camera3dBundle { camera_3d: Camera3d { // disables clearing clear_color: ClearColorConfig::None, ..default() }, ..default() }) ``` Expect to see more of the "graph configuration Components on Cameras" pattern in the future. By popular demand, UI no longer requires a dedicated camera. `UiCameraBundle` has been removed. `Camera2dBundle` and `Camera3dBundle` now both default to rendering UI as part of their own render graphs. To disable UI rendering for a camera, disable it using the CameraUi component: ```rust commands .spawn_bundle(Camera3dBundle::default()) .insert(CameraUi { is_enabled: false, ..default() }) ``` ## Other Changes * The separate clear pass has been removed. We should revisit this for things like sky rendering, but I think this PR should "keep it simple" until we're ready to properly support that (for code complexity and performance reasons). We can come up with the right design for a modular clear pass in a followup pr. * I reorganized bevy_core_pipeline into Core2dPlugin and Core3dPlugin (and core_2d / core_3d modules). Everything is pretty much the same as before, just logically separate. I've moved relevant types (like Camera2d, Camera3d, Camera3dBundle, Camera2dBundle) into their relevant modules, which is what motivated this reorganization. * I adapted the `scene_viewer` example (which relied on the ActiveCameras behavior) to the new system. I also refactored bits and pieces to be a bit simpler. * All of the examples have been ported to the new camera approach. `render_to_texture` and `multiple_windows` are now _much_ simpler. I removed `two_passes` because it is less relevant with the new approach. If someone wants to add a new "layered custom pass with CameraRenderGraph" example, that might fill a similar niche. But I don't feel much pressure to add that in this pr. * Cameras now have `target_logical_size` and `target_physical_size` fields, which makes finding the size of a camera's render target _much_ simpler. As a result, the `Assets<Image>` and `Windows` parameters were removed from `Camera::world_to_screen`, making that operation much more ergonomic. * Render order ambiguities between cameras with the same target and the same priority now produce a warning. This accomplishes two goals: 1. Now that there is no "global" active camera, by default spawning two cameras will result in two renders (one covering the other). This would be a silent performance killer that would be hard to detect after the fact. By detecting ambiguities, we can provide a helpful warning when this occurs. 2. Render order ambiguities could result in unexpected / unpredictable render results. Resolving them makes sense. ## Follow Up Work * Per-Camera viewports, which will make it possible to render to a smaller area inside of a RenderTarget (great for something like splitscreen) * Camera-specific MSAA config (should use the same "overriding" pattern used for ClearColor) * Graph Based Camera Ordering: priorities are simple, but they make complicated ordering constraints harder to express. We should consider adopting a "graph based" camera ordering model with "before" and "after" relationships to other cameras (or build it "on top" of the priority system). * Consider allowing graphs to run subgraphs from any nest level (aka a global namespace for graphs). Right now the 2d and 3d graphs each need their own UI subgraph, which feels "fine" in the short term. But being able to share subgraphs between other subgraphs seems valuable. * Consider splitting `bevy_core_pipeline` into `bevy_core_2d` and `bevy_core_3d` packages. Theres a shared "clear color" dependency here, which would need a new home. |
||
Thierry Berger
|
deeaf64897 |
shader examples wording coherence (#4810)
# Objective I noticed different examples descriptions were not using the same structure:  This results in sentences that a reader has to read differently each time, which might result in information being hard to find, especially foreign language users. Original discord discussion: https://discord.com/channels/691052431525675048/976846499889705020 ## Solution - Use less different words, similar structure and being straight to the point. --- ## Changelog - Examples descriptions more accessible. |
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Mark Schmale
|
1ba7429371 |
Doc/module style doc blocks for examples (#4438)
# Objective Provide a starting point for #3951, or a partial solution. Providing a few comment blocks to discuss, and hopefully find better one in the process. ## Solution Since I am pretty new to pretty much anything in this context, I figured I'd just start with a draft for some file level doc blocks. For some of them I found more relevant details (or at least things I considered interessting), for some others there is less. ## Changelog - Moved some existing comments from main() functions in the 2d examples to the file header level - Wrote some more comment blocks for most other 2d examples TODO: - [x] 2d/sprite_sheet, wasnt able to come up with something good yet - [x] all other example groups... Also: Please let me know if the commit style is okay, or to verbose. I could certainly squash these things, or add more details if needed. I also hope its okay to raise this PR this early, with just a few files changed. Took me long enough and I dont wanted to let it go to waste because I lost motivation to do the whole thing. Additionally I am somewhat uncertain over the style and contents of the commets. So let me know what you thing please. |
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|
Carter Anderson
|
b6a647cc01 |
default() shorthand (#4071)
Adds a `default()` shorthand for `Default::default()` ... because life is too short to constantly type `Default::default()`.
```rust
use bevy::prelude::*;
#[derive(Default)]
struct Foo {
bar: usize,
baz: usize,
}
// Normally you would do this:
let foo = Foo {
bar: 10,
..Default::default()
};
// But now you can do this:
let foo = Foo {
bar: 10,
..default()
};
```
The examples have been adapted to use `..default()`. I've left internal crates as-is for now because they don't pull in the bevy prelude, and the ergonomics of each case should be considered individually.
|
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Jakob Hellermann
|
3ffa655cdd |
examples: add screenspace texture shader example (#4063)
Adds a new shader example showing how to sample a texture with screenspace coordinates, similar to the end [portal in minecraft](https://bugs.mojang.com/secure/attachment/163759/portal_frame_112.gif). https://user-images.githubusercontent.com/22177966/156031195-33d14ed8-733f-4d9e-b1da-0fc807c994a5.mp4 I just used the already existent `models/FlightHelmet/FlightHelmet_Materials_LensesMat_OcclusionRoughMetal.png` texture but maybe we should use a dedicated texture for the example. Suggestions welcome. Co-authored-by: Carter Anderson <mcanders1@gmail.com> |
