# Objective
- @mockersf identified a performance regression of about 25% longer frame times introduced by #7784 in a complex scene with the Amazon Lumberyard bistro scene with both exterior and interior variants and a number of point lights with shadow mapping enabled
- The additional time seemed to be spent in the `ShadowPassNode`
- `ShadowPassNode` encodes the draw commands for the shadow phase. Roughly the same numbers of entities were having draw commands encoded, so something about the way they were being encoded had changed.
- One thing that definitely changed was that the pipeline used will be different depending on the alpha mode, and the scene has lots entities with opaque and blend materials. This suggested that maybe the pipeline was changing a lot so I tried a quick hack to see if it was the problem.
## Solution
- Sort the shadow phase items by their pipeline id
- This groups phase items by their pipeline id, which significantly reduces pipeline rebinding required to the point that the performance regression was gone.
# Objective
revert combining pipelines for AlphaMode::Blend and AlphaMode::Premultiplied & Add
the recent blend state pr changed `AlphaMode::Blend` to use a blend state of `Blend::PREMULTIPLIED_ALPHA_BLENDING`, and recovered the original behaviour by multiplying colour by alpha in the standard material's fragment shader.
this had some advantages (specifically it means more material instances can be batched together in future), but this also means that custom materials that specify `AlphaMode::Blend` now get a premultiplied blend state, so they must also multiply colour by alpha.
## Solution
revert that combination to preserve 0.9 behaviour for custom materials with AlphaMode::Blend.
This produces more accurate results for the `EmissiveStrengthTest` glTF test case.
(Requires manually setting the emission, for now)
Before: <img width="1392" alt="Screenshot 2023-03-04 at 18 21 25" src="https://user-images.githubusercontent.com/418473/222929455-c7363d52-7133-4d4e-9d6a-562098f6bbe8.png">
After: <img width="1392" alt="Screenshot 2023-03-04 at 18 20 57" src="https://user-images.githubusercontent.com/418473/222929454-3ea20ecb-0773-4aad-978c-3832353b6871.png">
Tagging @JMS55 as a co-author, since this fix is based on their experiments with emission.
# Objective
- Have more accurate results for the `EmissiveStrengthTest` glTF test case.
## Solution
- Make sure we send the emissive color as linear instead of sRGB.
---
## Changelog
- Emission strength is now correctly interpreted by the `StandardMaterial` as linear instead of sRGB.
## Migration Guide
- If you have previously manually specified emissive values with `Color::rgb()` and would like to retain the old visual results, you must now use `Color::rgb_linear()` instead;
- If you have previously manually specified emissive values with `Color::rgb_linear()` and would like to retain the old visual results, you'll need to apply a one-time gamma calculation to your channels manually to get the _actual_ linear RGB value:
- For channel values greater than `0.0031308`, use `(1.055 * value.powf(1.0 / 2.4)) - 0.055`;
- For channel values lower than or equal to `0.0031308`, use `value * 12.92`;
- Otherwise, the results should now be more consistent with other tools/engines.
# Objective
the current depth bias only adjusts ordering, so it doesn't work for opaque meshes vs alpha-blend meshes, and it doesn't help when two meshes are infinitesimally offset from one another.
## Solution
pass the material's depth bias into the pipeline depth stencil `constant` field.
# Objective
Unfortunately, there are three issues with my changes introduced by #7784.
1. The changes left some dead code. This is already taken care of here: #7875.
2. Disabling prepass causes failures because the shadow mapping relies on the `PrepassPlugin` now.
3. Custom materials use the `prepass.wgsl` shader, but this does not always define a fragment entry point.
This PR fixes 2. and 3. and resolves#7879.
## Solution
- Add a regression test with disabled prepass.
- Split `PrepassPlugin` into two plugins:
- `PrepassPipelinePlugin` contains the part that is required for the shadow mapping to work and is unconditionally added.
- `PrepassPlugin` now only adds the systems and resources required for the "real" prepasses.
- Add a noop fragment entry point to `prepass.wgsl`, used if `NORMAL_PASS` is not defined.
Co-authored-by: Edgar Geier <geieredgar@gmail.com>
# Objective
- Remove dead code after #7784
# Changelog
- Removed `SetShadowViewBindGroup`, `queue_shadow_view_bind_group()`, and `LightMeta::shadow_view_bind_group` in favor of reusing the prepass view bind group.
# Migration Guide
- Removed `SetShadowViewBindGroup`, `queue_shadow_view_bind_group()`, and `LightMeta::shadow_view_bind_group` in favor of reusing the prepass view bind group.
# Objective
- Fixes#4372.
## Solution
- Use the prepass shaders for the shadow passes.
- Move `DEPTH_CLAMP_ORTHO` from `ShadowPipelineKey` to `MeshPipelineKey` and the associated clamp operation from `depth.wgsl` to `prepass.wgsl`.
- Remove `depth.wgsl` .
- Replace `ShadowPipeline` with `ShadowSamplers`.
Instead of running the custom `ShadowPipeline` we run the `PrepassPipeline` with the `DEPTH_PREPASS` flag and additionally the `DEPTH_CLAMP_ORTHO` flag for directional lights as well as the `ALPHA_MASK` flag for materials that use `AlphaMode::Mask(_)`.
# Objective
Fixes#7797
## Solution
This **seems** like a simple fix, but I'm not 100% confident and I may have messed up the math in some way. In particular, I'm not sure what I should be using for an FOV value.
However, this seems to be producing similar results to 0.9.
Here's the `orthographic` example with a default directional light.
edit: better screen grab below.
# Objective
- Use the prepass textures in webgl
## Solution
- Bind the prepass textures even when using webgl, but only if msaa is disabled
- Also did some refactors to centralize how textures are bound, similar to the EnvironmentMapLight PR
- ~~Also did some refactors of the example to make it work in webgl~~
- ~~To make the example work in webgl, I needed to use a sampler for the depth texture, the resulting code looks a bit weird, but it's simple enough and I think it's worth it to show how it works when using webgl~~
# Objective
Support the following syntax for adding systems:
```rust
App::new()
.add_system(setup.on_startup())
.add_systems((
show_menu.in_schedule(OnEnter(GameState::Paused)),
menu_ssytem.in_set(OnUpdate(GameState::Paused)),
hide_menu.in_schedule(OnExit(GameState::Paused)),
))
```
## Solution
Add the traits `IntoSystemAppConfig{s}`, which provide the extension methods necessary for configuring which schedule a system belongs to. These extension methods return `IntoSystemAppConfig{s}`, which `App::add_system{s}` uses to choose which schedule to add systems to.
---
## Changelog
+ Added the extension methods `in_schedule(label)` and `on_startup()` for configuring the schedule a system belongs to.
## Future Work
* Replace all uses of `add_startup_system` in the engine.
* Deprecate this method
# Objective
- ambiguities bad
## Solution
- solve ambiguities
- by either ignoring (e.g. on `queue_mesh_view_bind_groups` since `LightMeta` access is different)
- by introducing a dependency (`prepare_windows -> prepare_*` because the latter use the fallback Msaa)
- make `prepare_assets` public so that we can do a proper `.after`
# Objective
Currently, it is quite awkward to use the `pbr` function in a custom shader without binding a mesh bind group.
This is because the `pbr` function depends on the `MESH_FLAGS_SHADOW_RECEIVER_BIT` flag.
## Solution
I have removed this dependency by adding the flag as a parameter to the `PbrInput` struct.
I am not sure if this is the ideal solution since the mesh flag indicates both `MESH_FLAGS_SIGN_DETERMINANT_MODEL_3X3_BIT` and `MESH_FLAGS_SHADOW_RECEIVER_BIT`.
The former seems to be unrelated to PBR. Maybe the flag should be split.
# Objective
- Fix the environment map shader not working under webgl due to textureNumLevels() not being supported
- Fixes https://github.com/bevyengine/bevy/issues/7722
## Solution
- Instead of using textureNumLevels(), put an extra field in the GpuLights uniform to store the mip count
# Objective
Splits tone mapping from https://github.com/bevyengine/bevy/pull/6677 into a separate PR.
Address https://github.com/bevyengine/bevy/issues/2264.
Adds tone mapping options:
- None: Bypasses tonemapping for instances where users want colors output to match those set.
- Reinhard
- Reinhard Luminance: Bevy's exiting tonemapping
- [ACES](https://github.com/TheRealMJP/BakingLab/blob/master/BakingLab/ACES.hlsl) (Fitted version, based on the same implementation that Godot 4 uses) see https://github.com/bevyengine/bevy/issues/2264
- [AgX](https://github.com/sobotka/AgX)
- SomewhatBoringDisplayTransform
- TonyMcMapface
- Blender Filmic
This PR also adds support for EXR images so they can be used to compare tonemapping options with reference images.
## Migration Guide
- Tonemapping is now an enum with NONE and the various tonemappers.
- The DebandDither is now a separate component.
Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
# Objective
Allow for creating pipelines that use push constants. To be able to use push constants. Fixes#4825
As of right now, trying to call `RenderPass::set_push_constants` will trigger the following error:
```
thread 'main' panicked at 'wgpu error: Validation Error
Caused by:
In a RenderPass
note: encoder = `<CommandBuffer-(0, 59, Vulkan)>`
In a set_push_constant command
provided push constant is for stage(s) VERTEX | FRAGMENT | VERTEX_FRAGMENT, however the pipeline layout has no push constant range for the stage(s) VERTEX | FRAGMENT | VERTEX_FRAGMENT
```
## Solution
Add a field push_constant_ranges to` RenderPipelineDescriptor` and `ComputePipelineDescriptor`.
This PR supersedes #4908 which now contains merge conflicts due to significant changes to `bevy_render`.
Meanwhile, this PR also made the `layout` field of `RenderPipelineDescriptor` and `ComputePipelineDescriptor` non-optional. If the user do not need to specify the bind group layouts, they can simply supply an empty vector here. No need for it to be optional.
---
## Changelog
- Add a field push_constant_ranges to RenderPipelineDescriptor and ComputePipelineDescriptor
- Made the `layout` field of RenderPipelineDescriptor and ComputePipelineDescriptor non-optional.
## Migration Guide
- Add push_constant_ranges: Vec::new() to every `RenderPipelineDescriptor` and `ComputePipelineDescriptor`
- Unwrap the optional values on the `layout` field of `RenderPipelineDescriptor` and `ComputePipelineDescriptor`. If the descriptor has no layout, supply an empty vector.
Co-authored-by: Zhixing Zhang <me@neoto.xin>
# Objective
We have a few old system labels that are now system sets but are still named or documented as labels. Documentation also generally mentioned system labels in some places.
## Solution
- Clean up naming and documentation regarding system sets
## Migration Guide
`PrepareAssetLabel` is now called `PrepareAssetSet`
# Objective
Standard material defaults are currently strange, and the docs are wrong re: metallic.
## Solution
Change the defaults to be similar to [Godot](https://github.com/godotengine/godot/pull/62756).
---
## Changelog
#### Changed
- `StandardMaterial` now defaults to a dielectric material (0.0 `metallic`) with 0.5 `perceptual_roughness`.
## Migration Guide
`StandardMaterial`'s default have now changed to be a fully dielectric material with medium roughness. If you want to use the old defaults, you can set `perceptual_roughness = 0.089` and `metallic = 0.01` (though metallic should generally only be set to 0.0 or 1.0).
# Objective
- rebased version of #6155
The `MaterialPipeline` cannot be integrated into other pipelines like the `MeshPipeline`.
## Solution
Implement `Clone` for `MaterialPipeline`. Expose systems and resources part of the `MaterialPlugin` to allow custom assembly - especially combining existing systems and resources with a custom `queue_material_meshes` system.
# Changelog
## Added
- Clone impl for MaterialPipeline
## Changed
- ExtractedMaterials, extract_materials and prepare_materials are now public
fixes#6799
# Objective
We should be able to reuse the `Globals` or `View` shader struct definitions from anywhere (including third party plugins) without needing to worry about defining unrelated shader defs.
Also we'd like to refactor these structs to not be repeatedly defined.
## Solution
Refactor both `Globals` and `View` into separate importable shaders.
Use the imports throughout.
Co-authored-by: Torstein Grindvik <52322338+torsteingrindvik@users.noreply.github.com>
(Before)
![image](https://user-images.githubusercontent.com/47158642/213946111-15ec758f-1f1d-443c-b196-1fdcd4ae49da.png)
(After)
![image](https://user-images.githubusercontent.com/47158642/217051179-67381e73-dd44-461b-a2c7-87b0440ef8de.png)
![image](https://user-images.githubusercontent.com/47158642/212492404-524e4ad3-7837-4ed4-8b20-2abc276aa8e8.png)
# Objective
- Improve lighting; especially reflections.
- Closes https://github.com/bevyengine/bevy/issues/4581.
## Solution
- Implement environment maps, providing better ambient light.
- Add microfacet multibounce approximation for specular highlights from Filament.
- Occlusion is no longer incorrectly applied to direct lighting. It now only applies to diffuse indirect light. Unsure if it's also supposed to apply to specular indirect light - the glTF specification just says "indirect light". In the case of ambient occlusion, for instance, that's usually only calculated as diffuse though. For now, I'm choosing to apply this just to indirect diffuse light, and not specular.
- Modified the PBR example to use an environment map, and have labels.
- Added `FallbackImageCubemap`.
## Implementation
- IBL technique references can be found in environment_map.wgsl.
- It's more accurate to use a LUT for the scale/bias. Filament has a good reference on generating this LUT. For now, I just used an analytic approximation.
- For now, environment maps must first be prefiltered outside of bevy using a 3rd party tool. See the `EnvironmentMap` documentation.
- Eventually, we should have our own prefiltering code, so that we can have dynamically changing environment maps, as well as let users drop in an HDR image and use asset preprocessing to create the needed textures using only bevy.
---
## Changelog
- Added an `EnvironmentMapLight` camera component that adds additional ambient light to a scene.
- StandardMaterials will now appear brighter and more saturated at high roughness, due to internal material changes. This is more physically correct.
- Fixed StandardMaterial occlusion being incorrectly applied to direct lighting.
- Added `FallbackImageCubemap`.
Co-authored-by: IceSentry <c.giguere42@gmail.com>
Co-authored-by: James Liu <contact@jamessliu.com>
Co-authored-by: Rob Parrett <robparrett@gmail.com>
# Objective
Fix#7377Fix#7513
## Solution
Record the changes made to the Bevy `Window` from `winit` as 'canon' to avoid Bevy sending those changes back to `winit` again, causing a feedback loop.
## Changelog
* Removed `ModifiesWindows` system label.
Neither `despawn_window` nor `changed_window` actually modify the `Window` component so all the `.after(ModifiesWindows)` shouldn't be necessary.
* Moved `changed_window` and `despawn_window` systems to `CoreStage::Last` to avoid systems making changes to the `Window` between `changed_window` and the end of the frame as they would be ignored.
## Migration Guide
The `ModifiesWindows` system label was removed.
Co-authored-by: devil-ira <justthecooldude@gmail.com>
# Objective
add a hook for ambient occlusion to the pbr shader
## Solution
add a hook for ambient occlusion to the pbr shader
Co-authored-by: atlas dostal <rodol@rivalrebels.com>
# Objective
Some render systems that have system set used as a label so that they can be referenced from somewhere else.
The 1:1 translation from `add_system_to_stage(Prepare, prepare_lights.label(PrepareLights))` is `add_system(prepare_lights.in_set(Prepare).in_set(PrepareLights)`, but configuring the `PrepareLights` set to be in `Prepare` would match the intention better (there are no systems in `PrepareLights` outside of `Prepare`) and it is easier for visualization tools to deal with.
# Solution
- replace
```rust
prepare_lights in PrepareLights
prepare_lights in Prepare
```
with
```rs
prepare_lights in PrepareLights
PrepareLights in Prepare
```
**Before**
![before](https://user-images.githubusercontent.com/22177966/216961792-a0f5eba7-f161-4994-b5a4-33e98763a3b0.svg)
**After**
![after](https://user-images.githubusercontent.com/22177966/216961790-857d0062-7943-49ef-8927-e602dfbab714.svg)
# 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
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.
# Objective
- Improve ergonomics / documentation of cascaded shadow maps
- Allow for the customization of the nearest shadowing distance.
- Fixes#7393
- Fixes#7362
## Solution
- Introduce `CascadeShadowConfigBuilder`
- Tweak various example cascade settings for better quality.
---
## Changelog
- Made examples look nicer under cascaded shadow maps.
- Introduce `CascadeShadowConfigBuilder` to help with creating `CascadeShadowConfig`
## Migration Guide
- Configure settings for cascaded shadow maps for directional lights using the newly introduced `CascadeShadowConfigBuilder`.
Co-authored-by: Robert Swain <robert.swain@gmail.com>
# Objective
- Bevy should not have any "internal" execution order ambiguities. These clutter the output of user-facing error reporting, and can result in nasty, nondetermistic, very difficult to solve bugs.
- Verifying this currently involves repeated non-trivial manual work.
## Solution
- [x] add an example to quickly check this
- ~~[ ] ensure that this example panics if there are any unresolved ambiguities~~
- ~~[ ] run the example in CI 😈~~
There's one tricky ambiguity left, between UI and animation. I don't have the tools to fix this without system set configuration, so the remaining work is going to be left to #7267 or another PR after that.
```
2023-01-27T18:38:42.989405Z INFO bevy_ecs::schedule::ambiguity_detection: Execution order ambiguities detected, you might want to add an explicit dependency relation between some of these systems:
* Parallel systems:
-- "bevy_animation::animation_player" and "bevy_ui::flex::flex_node_system"
conflicts: ["bevy_transform::components::transform::Transform"]
```
## Changelog
Resolved internal execution order ambiguities for:
1. Transform propagation (ignored, we need smarter filter checking).
2. Gamepad processing (fixed).
3. bevy_winit's window handling (fixed).
4. Cascaded shadow maps and perspectives (fixed).
Also fixed a desynchronized state bug that could occur when the `Window` component is removed and then added to the same entity in a single frame.
# Objective
- Fix a bug causing performance to drop over time because the GPU fog buffer was endlessly growing
## Solution
- Clear the fog buffer every frame before populating it
# Objective
- Fix `post_processing` and `shader_prepass` examples as they fail when compiling shaders due to missing shader defs
- Fixes#6799
- Fixes#6996
- Fixes#7375
- Supercedes #6997
- Supercedes #7380
## Solution
- The prepass was broken due to a missing `MAX_CASCADES_PER_LIGHT` shader def. Add it.
- The shader used in the `post_processing` example is applied to a 2D mesh, so use the correct mesh2d_view_bindings shader import.
# Objective
In simple cases we might want to derive the `ExtractComponent` trait.
This adds symmetry to the existing `ExtractResource` derive.
## Solution
Add an implementation of `#[derive(ExtractComponent)]`.
The implementation is adapted from the existing `ExtractResource` derive macro.
Additionally, there is an attribute called `extract_component_filter`. This allows specifying a query filter type used when extracting.
If not specified, no filter (equal to `()`) is used.
So:
```rust
#[derive(Component, Clone, ExtractComponent)]
#[extract_component_filter(With<Fuel>)]
pub struct Car {
pub wheels: usize,
}
```
would expand to (a bit cleaned up here):
```rust
impl ExtractComponent for Car
{
type Query = &'static Self;
type Filter = With<Fuel>;
type Out = Self;
fn extract_component(item: QueryItem<'_, Self::Query>) -> Option<Self::Out> {
Some(item.clone())
}
}
```
---
## Changelog
- Added the ability to `#[derive(ExtractComponent)]` with an optional filter.
# Objective
Update Bevy to wgpu 0.15.
## Changelog
- Update to wgpu 0.15, wgpu-hal 0.15.1, and naga 0.11
- Users can now use the [DirectX Shader Compiler](https://github.com/microsoft/DirectXShaderCompiler) (DXC) on Windows with DX12 for faster shader compilation and ShaderModel 6.0+ support (requires `dxcompiler.dll` and `dxil.dll`, which are included in DXC downloads from [here](https://github.com/microsoft/DirectXShaderCompiler/releases/latest))
## Migration Guide
### WGSL Top-Level `let` is now `const`
All top level constants are now declared with `const`, catching up with the wgsl spec.
`let` is no longer allowed at the global scope, only within functions.
```diff
-let SOME_CONSTANT = 12.0;
+const SOME_CONSTANT = 12.0;
```
#### `TextureDescriptor` and `SurfaceConfiguration` now requires a `view_formats` field
The new `view_formats` field in the `TextureDescriptor` is used to specify a list of formats the texture can be re-interpreted to in a texture view. Currently only changing srgb-ness is allowed (ex. `Rgba8Unorm` <=> `Rgba8UnormSrgb`). You should set `view_formats` to `&[]` (empty) unless you have a specific reason not to.
#### The DirectX Shader Compiler (DXC) is now supported on DX12
DXC is now the default shader compiler when using the DX12 backend. DXC is Microsoft's replacement for their legacy FXC compiler, and is faster, less buggy, and allows for modern shader features to be used (ShaderModel 6.0+). DXC requires `dxcompiler.dll` and `dxil.dll` to be available, otherwise it will log a warning and fall back to FXC.
You can get `dxcompiler.dll` and `dxil.dll` by downloading the latest release from [Microsoft's DirectXShaderCompiler github repo](https://github.com/microsoft/DirectXShaderCompiler/releases/latest) and copying them into your project's root directory. These must be included when you distribute your Bevy game/app/etc if you plan on supporting the DX12 backend and are using DXC.
`WgpuSettings` now has a `dx12_shader_compiler` field which can be used to choose between either FXC or DXC (if you pass None for the paths for DXC, it will check for the .dlls in the working directory).
<img width="1392" alt="image" src="https://user-images.githubusercontent.com/418473/203873533-44c029af-13b7-4740-8ea3-af96bd5867c9.png">
<img width="1392" alt="image" src="https://user-images.githubusercontent.com/418473/203873549-36be7a23-b341-42a2-8a9f-ceea8ac7a2b8.png">
# Objective
- Add support for the “classic” distance fog effect, as well as a more advanced atmospheric fog effect.
## Solution
This PR:
- Introduces a new `FogSettings` component that controls distance fog per-camera.
- Adds support for three widely used “traditional” fog falloff modes: `Linear`, `Exponential` and `ExponentialSquared`, as well as a more advanced `Atmospheric` fog;
- Adds support for directional light influence over fog color;
- Extracts fog via `ExtractComponent`, then uses a prepare system that sets up a new dynamic uniform struct (`Fog`), similar to other mesh view types;
- Renders fog in PBR material shader, as a final adjustment to the `output_color`, after PBR is computed (but before tone mapping);
- Adds a new `StandardMaterial` flag to enable fog; (`fog_enabled`)
- Adds convenience methods for easier artistic control when creating non-linear fog types;
- Adds documentation around fog.
---
## Changelog
### Added
- Added support for distance-based fog effects for PBR materials, controllable per-camera via the new `FogSettings` component;
- Added `FogFalloff` enum for selecting between three widely used “traditional” fog falloff modes: `Linear`, `Exponential` and `ExponentialSquared`, as well as a more advanced `Atmospheric` fog;
# Objective
I found several words in code and docs are incorrect. This should be fixed.
## Solution
- Fix several minor typos
Co-authored-by: Chris Ohk <utilforever@gmail.com>
# Objective
Prevent things from breaking tomorrow when rust 1.67 is released.
## Solution
Fix a few `uninlined_format_args` lints in recently introduced code.
Co-authored-by: Robert Swain <robert.swain@gmail.com>
# Objective
Implements cascaded shadow maps for directional lights, which produces better quality shadows without needing excessively large shadow maps.
Fixes#3629
Before
![image](https://user-images.githubusercontent.com/1222141/210061203-bbd965a4-8d11-4cec-9a88-67fc59d0819f.png)
After
![image](https://user-images.githubusercontent.com/1222141/210061334-2ff15334-e6d7-4a31-9314-f34a7805cac6.png)
## Solution
Rather than rendering a single shadow map for directional light, the view frustum is divided into a series of cascades, each of which gets its own shadow map. The correct cascade is then sampled for shadow determination.
---
## Changelog
Directional lights now use cascaded shadow maps for improved shadow quality.
## Migration Guide
You no longer have to manually specify a `shadow_projection` for a directional light, and these settings should be removed. If customization of how cascaded shadow maps work is desired, modify the `CascadeShadowConfig` component instead.
# Objective
- The functions added to utils.wgsl by the prepass assume that mesh_view_bindings are present, which isn't always the case
- Fixes https://github.com/bevyengine/bevy/issues/7353
## Solution
- Move these functions to their own `prepass_utils.wgsl` file
Co-authored-by: IceSentry <IceSentry@users.noreply.github.com>
# Objective
- This PR adds support for blend modes to the PBR `StandardMaterial`.
<img width="1392" alt="Screenshot 2022-11-18 at 20 00 56" src="https://user-images.githubusercontent.com/418473/202820627-0636219a-a1e5-437a-b08b-b08c6856bf9c.png">
<img width="1392" alt="Screenshot 2022-11-18 at 20 01 01" src="https://user-images.githubusercontent.com/418473/202820615-c8d43301-9a57-49c4-bd21-4ae343c3e9ec.png">
## Solution
- The existing `AlphaMode` enum is extended, adding three more modes: `AlphaMode::Premultiplied`, `AlphaMode::Add` and `AlphaMode::Multiply`;
- All new modes are rendered in the existing `Transparent3d` phase;
- The existing mesh flags for alpha mode are reorganized for a more compact/efficient representation, and new values are added;
- `MeshPipelineKey::TRANSPARENT_MAIN_PASS` is refactored into `MeshPipelineKey::BLEND_BITS`.
- `AlphaMode::Opaque` and `AlphaMode::Mask(f32)` share a single opaque pipeline key: `MeshPipelineKey::BLEND_OPAQUE`;
- `Blend`, `Premultiplied` and `Add` share a single premultiplied alpha pipeline key, `MeshPipelineKey::BLEND_PREMULTIPLIED_ALPHA`. In the shader, color values are premultiplied accordingly (or not) depending on the blend mode to produce the three different results after PBR/tone mapping/dithering;
- `Multiply` uses its own independent pipeline key, `MeshPipelineKey::BLEND_MULTIPLY`;
- Example and documentation are provided.
---
## Changelog
### Added
- Added support for additive and multiplicative blend modes in the PBR `StandardMaterial`, via `AlphaMode::Add` and `AlphaMode::Multiply`;
- Added support for premultiplied alpha in the PBR `StandardMaterial`, via `AlphaMode::Premultiplied`;
# Objective
Fixes#6931
Continues #6954 by squashing `Msaa` to a flat enum
Helps out #7215
# Solution
```
pub enum Msaa {
Off = 1,
#[default]
Sample4 = 4,
}
```
# Changelog
- Modified
- `Msaa` is now enum
- Defaults to 4 samples
- Uses `.samples()` method to get the sample number as `u32`
# Migration Guide
```
let multi = Msaa { samples: 4 }
// is now
let multi = Msaa::Sample4
multi.samples
// is now
multi.samples()
```
Co-authored-by: Sjael <jakeobrien44@gmail.com>
# Objective
- Add a configurable prepass
- A depth prepass is useful for various shader effects and to reduce overdraw. It can be expansive depending on the scene so it's important to be able to disable it if you don't need any effects that uses it or don't suffer from excessive overdraw.
- The goal is to eventually use it for things like TAA, Ambient Occlusion, SSR and various other techniques that can benefit from having a prepass.
## Solution
The prepass node is inserted before the main pass. It runs for each `Camera3d` with a prepass component (`DepthPrepass`, `NormalPrepass`). The presence of one of those components is used to determine which textures are generated in the prepass. When any prepass is enabled, the depth buffer generated will be used by the main pass to reduce overdraw.
The prepass runs for each `Material` created with the `MaterialPlugin::prepass_enabled` option set to `true`. You can overload the shader used by the prepass by using `Material::prepass_vertex_shader()` and/or `Material::prepass_fragment_shader()`. It will also use the `Material::specialize()` for more advanced use cases. It is enabled by default on all materials.
The prepass works on opaque materials and materials using an alpha mask. Transparent materials are ignored.
The `StandardMaterial` overloads the prepass fragment shader to support alpha mask and normal maps.
---
## Changelog
- Add a new `PrepassNode` that runs before the main pass
- Add a `PrepassPlugin` to extract/prepare/queue the necessary data
- Add a `DepthPrepass` and `NormalPrepass` component to control which textures will be created by the prepass and available in later passes.
- Add a new `prepass_enabled` flag to the `MaterialPlugin` that will control if a material uses the prepass or not.
- Add a new `prepass_enabled` flag to the `PbrPlugin` to control if the StandardMaterial uses the prepass. Currently defaults to false.
- Add `Material::prepass_vertex_shader()` and `Material::prepass_fragment_shader()` to control the prepass from the `Material`
## Notes
In bevy's sample 3d scene, the performance is actually worse when enabling the prepass, but on more complex scenes the performance is generally better. I would like more testing on this, but @DGriffin91 has reported a very noticeable improvements in some scenes.
The prepass is also used by @JMS55 for TAA and GTAO
discord thread: <https://discord.com/channels/691052431525675048/1011624228627419187>
This PR was built on top of the work of multiple people
Co-Authored-By: @superdump
Co-Authored-By: @robtfm
Co-Authored-By: @JMS55
Co-authored-by: Charles <IceSentry@users.noreply.github.com>
Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
# Objective
- Allow rendering queue systems to use a `Res<PipelineCache>` even for queueing up new rendering pipelines. This is part of unblocking parallel execution queue systems.
## Solution
- Make `PipelineCache` internally mutable w.r.t to queueing new pipelines. Pipelines are no longer immediately updated into the cache state, but rather queued into a Vec. The Vec of pending new pipelines is then later processed at the same time we actually create the queued pipelines on the GPU device.
---
## Changelog
`PipelineCache` no longer requires mutable access in order to queue render / compute pipelines.
## Migration Guide
* Most usages of `resource_mut::<PipelineCache>` and `ResMut<PipelineCache>` can be changed to `resource::<PipelineCache>` and `Res<PipelineCache>` as long as they don't use any methods requiring mutability - the only public method requiring it is `process_queue`.
# Objective
Pipelines can be customized by wrapping an existing pipeline in a newtype and adding custom logic to its implementation of `SpecializedMeshPipeline::specialize`. To make that easier, the wrapped pipeline type needs to implement `Clone`.
For example, the current non-cloneable pipelines require wrapper pipelines to pull apart the wrapped pipeline like this:
```rust
impl FromWorld for Wireframe2dPipeline {
fn from_world(world: &mut World) -> Self {
let p = &world.resource::<Material2dPipeline<ColorMaterial>>();
Self {
mesh2d_pipeline: p.mesh2d_pipeline.clone(),
material2d_layout: p.material2d_layout.clone(),
vertex_shader: p.vertex_shader.clone(),
fragment_shader: p.fragment_shader.clone(),
}
}
}
```
## Solution
Derive or implement `Clone` on all built-in pipeline types. This is easy to do since they mostly just contain cheaply clonable reference-counted types.
---
## Changelog
Implement `Clone` for all pipeline types.
# Objective
fix error with shadow shader's spotlight direction calculation when direction.y ~= 0
fixes#7152
## Solution
same as #6167: in shadows.wgsl, clamp 1-x^2-z^2 to >= 0 so that we can safely sqrt it
# Objective
Speed up the render phase for rendering.
## Solution
- Follow up #6988 and make the internals of atomic IDs `NonZeroU32`. This niches the `Option`s of the IDs in draw state, which reduces the size and branching behavior when evaluating for equality.
- Require `&RenderDevice` to get the device's `Limits` when initializing a `TrackedRenderPass` to preallocate the bind groups and vertex buffer state in `DrawState`, this removes the branch on needing to resize those `Vec`s.
## Performance
This produces a similar speed up akin to that of #6885. This shows an approximate 6% speed up in `main_opaque_pass_3d` on `many_foxes` (408.79 us -> 388us). This should be orthogonal to the gains seen there.
![image](https://user-images.githubusercontent.com/3137680/209906239-e430f026-63c2-4b95-957e-a2045b810d79.png)
---
## Changelog
Added: `RenderContext::begin_tracked_render_pass`.
Changed: `TrackedRenderPass` now requires a `&RenderDevice` on construction.
Removed: `bevy_render::render_phase::DrawState`. It was not usable in any form outside of `bevy_render`.
## Migration Guide
TODO
# Objective
- Avoid slower than necessary first frame after spawning many entities due to them not having `Aabb`s and so being marked visible
- Avoids unnecessarily large system and VRAM allocations as a consequence
## Solution
- I noticed when debugging the `many_cubes` stress test in Xcode that the `MeshUniform` binding was much larger than it needed to be. I realised that this was because initially, all mesh entities are marked as being visible because they don't have `Aabb`s because `calculate_bounds` is being run in `PostUpdate` and there are no system commands applications before executing the visibility check systems that need the `Aabb`s. The solution then is to run the `calculate_bounds` system just before the previous system commands are applied which is at the end of the `Update` stage.
# Objective
Speed up the render phase of rendering. Simplify the trait structure for render commands.
## Solution
- Merge `EntityPhaseItem` into `PhaseItem` (`EntityPhaseItem::entity` -> `PhaseItem::entity`)
- Merge `EntityRenderCommand` into `RenderCommand`.
- Add two associated types to `RenderCommand`: `RenderCommand::ViewWorldQuery` and `RenderCommand::WorldQuery`.
- Use the new associated types to construct two `QueryStates`s for `RenderCommandState`.
- Hoist any `SQuery<T>` fetches in `EntityRenderCommand`s into the aformentioned two queries. Batch fetch them all at once.
## Performance
`main_opaque_pass_3d` is slightly faster on `many_foxes` (427.52us -> 401.15us)
![image](https://user-images.githubusercontent.com/3137680/206359804-9928b20a-7d92-41f8-bf7d-6e8c5cc802f0.png)
The shadow pass node is also slightly faster (344.52 -> 338.24us)
![image](https://user-images.githubusercontent.com/3137680/206359977-1212198d-f933-49a0-80f1-62ff88eb5727.png)
## Future Work
- Can we hoist the view level queries out of the core loop?
---
## Changelog
Added: `PhaseItem::entity`
Added: `RenderCommand::ViewWorldQuery` associated type.
Added: `RenderCommand::ItemorldQuery` associated type.
Added: `Draw<T>::prepare` optional trait function.
Removed: `EntityPhaseItem` trait
## Migration Guide
TODO
# Objective
- The #7064 PR had poor performance on an M1 Max in MacOS due to significant overuse of registers resulting in 'register spilling' where data that would normally be stored in registers on the GPU is instead stored in VRAM. The latency to read from/write to VRAM instead of registers incurs a significant performance penalty.
- Use of registers is a limiting factor in shader performance. Assignment of a struct from memory to a local variable can incur copies. Passing a variable that has struct type as an argument to a function can also incur copies. As such, these two cases can incur increased register usage and decreased performance.
## Solution
- Remove/avoid a number of assignments of light struct type data to local variables.
- Remove/avoid a number of passing light struct type variables/data as value arguments to shader functions.
# Objective
- The recently merged PR #7013 does not allow multiple `RenderPhase`s to share the same `RenderPass`.
- Due to the introduced overhead we want to minimize the number of `RenderPass`es recorded during each frame.
## Solution
- Take a constructed `TrackedRenderPass` instead of a `RenderPassDiscriptor` as a parameter to the `RenderPhase::render` method.
---
## Changelog
To enable multiple `RenderPhases` to share the same `TrackedRenderPass`,
the `RenderPhase::render` signature has changed.
```rust
pub fn render<'w>(
&self,
render_pass: &mut TrackedRenderPass<'w>,
world: &'w World,
view: Entity)
```
Co-authored-by: Kurt Kühnert <51823519+kurtkuehnert@users.noreply.github.com>
# Objective
All `RenderPhases` follow the same render procedure.
The same code is duplicated multiple times across the codebase.
## Solution
I simply extracted this code into a method on the `RenderPhase`.
This avoids code duplication and makes setting up new `RenderPhases` easier.
---
## Changelog
### Changed
You can now set up the rendering code of a `RenderPhase` directly using the `RenderPhase::render` method, instead of implementing it manually in your render graph node.
# Objective
Following #4402, extract systems run on the render world instead of the main world, and allow retained state operations on it's resources. We're currently extracting to `ExtractedJoints` and then copying it twice during Prepare. Once into `SkinnedMeshJoints` and again into the actual GPU buffer.
This makes #4902 obsolete.
## Solution
Cut out the middle copy and directly extract joints into `SkinnedMeshJoints` and remove `ExtractedJoints` entirely.
This also removes the per-frame allocation that is being made to send `ExtractedJoints` into the render world.
## Performance
On my local machine, this halves the time for `prepare_skinned _meshes` on `many_foxes` (195.75us -> 93.93us on average).
![image](https://user-images.githubusercontent.com/3137680/205427455-ab91a8a3-a6b0-4f0a-bd48-e54482c563b2.png)
---
## Changelog
Added: `BufferVec::truncate`
Added: `BufferVec::extend`
Changed: `SkinnedMeshJoints::build` now takes a `&mut BufferVec` instead of a `&mut Vec` as a parameter.
Removed: `ExtractedJoints`.
## Migration Guide
`ExtractedJoints` has been removed. Read the bound bones from `SkinnedMeshJoints` instead.
# Objective
- Fixes#6841
- In some case, the number of maximum storage buffers is `u32::MAX` which doesn't fit in a `i32`
## Solution
- Add an option to have a `u32` in a `ShaderDefVal`
# Objective
- Every usage of `DrawFunctionsInternals::get_id()` was followed by a `.unwrap()`. which just adds boilerplate.
## Solution
- Introduce a fallible version of `DrawFunctionsInternals::get_id()` and use it where possible.
- I also took the opportunity to improve the error message a little in the case where it fails.
---
## Changelog
- Added `DrawFunctionsInternals::id()`
# Objective
- Reduce confusion around uniform bindings in materials. I've seen multiple people on discord get confused by it because it uses a struct that is named the same in the rust code and the wgsl code, but doesn't contain the same data. Also, the only reason this works is mostly by chance because the memory happens to align correctly.
## Solution
- Remove the confusing parts of the doc
## Notes
It's not super clear in the diff why this causes confusion, but essentially, the rust code defines a `CustomMaterial` struct with a color and a texture, but in the wgsl code the struct with the same name only contains the color. People are confused by it because the struct in wgsl doesn't need to be there.
You _can_ have complex structs on each side and the macro will even combine it for you if you reuse a binding index, but as it is now, this example seems to confuse more than help people.
# Objective
- shaders defs can now have a `bool` or `int` value
- `#if SHADER_DEF <operator> 3`
- ok if `SHADER_DEF` is defined, has the correct type and pass the comparison
- `==`, `!=`, `>=`, `>`, `<`, `<=` supported
- `#SHADER_DEF` or `#{SHADER_DEF}`
- will be replaced by the value in the shader code
---
## Migration Guide
- replace `shader_defs.push(String::from("NAME"));` by `shader_defs.push("NAME".into());`
- if you used shader def `NO_STORAGE_BUFFERS_SUPPORT`, check how `AVAILABLE_STORAGE_BUFFER_BINDINGS` is now used in Bevy default shaders
# Objective
`add_node_edge` and `add_slot_edge` are fallible methods, but are always used with `.unwrap()`.
`input_node` is often unwrapped as well.
This points to having an infallible behaviour as default, with an alternative fallible variant if needed.
Improves readability and ergonomics.
## Solution
- Change `add_node_edge` and `add_slot_edge` to panic on error.
- Change `input_node` to panic on `None`.
- Add `try_add_node_edge` and `try_add_slot_edge` in case fallible methods are needed.
- Add `get_input_node` to still be able to get an `Option`.
---
## Changelog
### Added
- `try_add_node_edge`
- `try_add_slot_edge`
- `get_input_node`
### Changed
- `add_node_edge` is now infallible (panics on error)
- `add_slot_edge` is now infallible (panics on error)
- `input_node` now panics on `None`
## Migration Guide
Remove `.unwrap()` from `add_node_edge` and `add_slot_edge`.
For cases where the error was handled, use `try_add_node_edge` and `try_add_slot_edge` instead.
Remove `.unwrap()` from `input_node`.
For cases where the option was handled, use `get_input_node` instead.
Co-authored-by: Torstein Grindvik <52322338+torsteingrindvik@users.noreply.github.com>
# Objective
- Closes#5262
- Fix color banding caused by quantization.
## Solution
- Adds dithering to the tonemapping node from #3425.
- This is inspired by Godot's default "debanding" shader: https://gist.github.com/belzecue/
- Unlike Godot:
- debanding happens after tonemapping. My understanding is that this is preferred, because we are running the debanding at the last moment before quantization (`[f32, f32, f32, f32]` -> `f32`). This ensures we aren't biasing the dithering strength by applying it in a different (linear) color space.
- This code instead uses and reference the origin source, Valve at GDC 2015
![Screenshot from 2022-11-10 13-44-46](https://user-images.githubusercontent.com/2632925/201218880-70f4cdab-a1ed-44de-a88c-8759e77197f1.png)
![Screenshot from 2022-11-10 13-41-11](https://user-images.githubusercontent.com/2632925/201218883-72393352-b162-41da-88bb-6e54a1e26853.png)
## Additional Notes
Real time rendering to standard dynamic range outputs is limited to 8 bits of depth per color channel. Internally we keep everything in full 32-bit precision (`vec4<f32>`) inside passes and 16-bit between passes until the image is ready to be displayed, at which point the GPU implicitly converts our `vec4<f32>` into a single 32bit value per pixel, with each channel (rgba) getting 8 of those 32 bits.
### The Problem
8 bits of color depth is simply not enough precision to make each step invisible - we only have 256 values per channel! Human vision can perceive steps in luma to about 14 bits of precision. When drawing a very slight gradient, the transition between steps become visible because with a gradient, neighboring pixels will all jump to the next "step" of precision at the same time.
### The Solution
One solution is to simply output in HDR - more bits of color data means the transition between bands will become smaller. However, not everyone has hardware that supports 10+ bit color depth. Additionally, 10 bit color doesn't even fully solve the issue, banding will result in coherent bands on shallow gradients, but the steps will be harder to perceive.
The solution in this PR adds noise to the signal before it is "quantized" or resampled from 32 to 8 bits. Done naively, it's easy to add unneeded noise to the image. To ensure dithering is correct and absolutely minimal, noise is adding *within* one step of the output color depth. When converting from the 32bit to 8bit signal, the value is rounded to the nearest 8 bit value (0 - 255). Banding occurs around the transition from one value to the next, let's say from 50-51. Dithering will never add more than +/-0.5 bits of noise, so the pixels near this transition might round to 50 instead of 51 but will never round more than one step. This means that the output image won't have excess variance:
- in a gradient from 49 to 51, there will be a step between each band at 49, 50, and 51.
- Done correctly, the modified image of this gradient will never have a adjacent pixels more than one step (0-255) from each other.
- I.e. when scanning across the gradient you should expect to see:
```
|-band-| |-band-| |-band-|
Baseline: 49 49 49 50 50 50 51 51 51
Dithered: 49 50 49 50 50 51 50 51 51
Dithered (wrong): 49 50 51 49 50 51 49 51 50
```
![Screenshot from 2022-11-10 14-12-36](https://user-images.githubusercontent.com/2632925/201219075-ab3f46be-d4e9-4869-b66b-a92e1706f49e.png)
![Screenshot from 2022-11-10 14-11-48](https://user-images.githubusercontent.com/2632925/201219079-ec5d2add-817d-487a-8fc1-84569c9cda73.png)
You can see from above how correct dithering "fuzzes" the transition between bands to reduce distinct steps in color, without adding excess noise.
### HDR
The previous section (and this PR) assumes the final output is to an 8-bit texture, however this is not always the case. When Bevy adds HDR support, the dithering code will need to take the per-channel depth into account instead of assuming it to be 0-255. Edit: I talked with Rob about this and it seems like the current solution is okay. We may need to revisit once we have actual HDR final image output.
---
## Changelog
### Added
- All pipelines now support deband dithering. This is enabled by default in 3D, and can be toggled in the `Tonemapping` component in camera bundles. Banding is a graphical artifact created when the rendered image is crunched from high precision (f32 per color channel) down to the final output (u8 per channel in SDR). This results in subtle gradients becoming blocky due to the reduced color precision. Deband dithering applies a small amount of noise to the signal before it is "crunched", which breaks up the hard edges of blocks (bands) of color. Note that this does not add excess noise to the image, as the amount of noise is less than a single step of a color channel - just enough to break up the transition between color blocks in a gradient.
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
- Make the many foxes not unnecessarily bright. Broken since #5666.
- Fixes#6528
## Solution
- In #5666 normalisation of normals was moved from the fragment stage to the vertex stage. However, it was not added to the vertex stage for skinned normals. The many foxes are skinned and their skinned normals were not unit normals. which made them brighter. Normalising the skinned normals fixes this.
---
## Changelog
- Fixed: Non-unit length skinned normals are now normalized.
# Objective
- it would be useful to inspect these structs using reflection
## Solution
- derive and register reflect
- Note that `#[reflect(Component)]` requires `Default` (or `FromWorld`) until #6060, so I implemented `Default` for `Tonemapping` with `is_enabled: false`
# Objective
Fixes#5393
## Solution
- Add padding to `GlobalsUniform` / `Globals` to make it 16-byte aligned.
Still not super clear on whether this is a `naga` thing or an `encase` thing or what. But now that we're offering `globals` up to users and #5393 is not just breaking an example, maybe we should do this sort of workaround?
# Objective
This PR fixes#5789, by enabling movable (and scalable) directional light shadow volumes.
## Solution
This PR changes `ExtractedDirectionalLight` to hold a copy of the `DirectionalLight` entity's `GlobalTransform`, instead of just a `direction` vector. This allows the shadow map volume (as defined by the light's `shadow_projection` field) to be transformed honoring translation _and_ scale transforms, and not just rotation.
It also augments the texel size calculation (used to determine the `shadow_normal_bias`) so that it now takes into account the upper bound of the x/y/z scale of the `GlobalTransform`.
This change makes the directional light extraction code more consistent with point and spot lights (that already use `transform`), and allows easily moving and scaling the shadow volume along with a player entity based on camera distance/angle, immediately enabling more real world use cases until we have a more sophisticated adaptive implementation, such as the one described in #3629.
**Note:** While it was previously possible to update the projection achieving a similar effect, depending on the light direction and distance to the origin, the fact that the shadow map camera was always positioned at the origin with a hardcoded `Vec3::Y` up value meant you would get sub-optimal or inconsistent/incorrect results.
---
## Changelog
### Changed
- `DirectionalLight` shadow volumes now honor translation and scale transforms
## Migration Guide
- If your directional lights were positioned at the origin and not scaled (the default, most common scenario) no changes are needed on your part; it just works as before;
- If you previously had a system for dynamically updating directional light shadow projections, you might now be able to simplify your code by updating the directional light entity's transform instead;
- In the unlikely scenario that a scene with directional lights that previously rendered shadows correctly has missing shadows, make sure your directional lights are positioned at (0, 0, 0) and are not scaled to a size that's too large or too small.
# Objective
- Adds a bloom pass for HDR-enabled Camera3ds.
- Supersedes (and all credit due to!) https://github.com/bevyengine/bevy/pull/3430 and https://github.com/bevyengine/bevy/pull/2876
![image](https://user-images.githubusercontent.com/47158642/198698783-228edc00-20b5-4218-a613-331ccd474f38.png)
## Solution
- A threshold is applied to isolate emissive samples, and then a series of downscale and upscaling passes are applied and composited together.
- Bloom is applied to 2d or 3d Cameras with hdr: true and a BloomSettings component.
---
## Changelog
- Added a `core_pipeline::bloom::BloomSettings` component.
- Added `BloomNode` that runs between the main pass and tonemapping.
- Added a `BloomPlugin` that is loaded as part of CorePipelinePlugin.
- Added a bloom example project.
Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
Co-authored-by: DGriffin91 <github@dgdigital.net>
# Objective
- Fixes#4019
- Fix lighting of double-sided materials when using a negative scale
- The FlightHelmet.gltf model's hose uses a double-sided material. Loading the model with a uniform scale of -1.0, and comparing against Blender, it was identified that negating the world-space tangent, bitangent, and interpolated normal produces incorrect lighting. Discussion with Morten Mikkelsen clarified that this is both incorrect and unnecessary.
## Solution
- Remove the code that negates the T, B, and N vectors (the interpolated world-space tangent, calculated world-space bitangent, and interpolated world-space normal) when seeing the back face of a double-sided material with negative scale.
- Negate the world normal for a double-sided back face only when not using normal mapping
### Before, on `main`, flipping T, B, and N
<img width="932" alt="Screenshot 2022-08-22 at 15 11 53" src="https://user-images.githubusercontent.com/302146/185965366-f776ff2c-cfa1-46d1-9c84-fdcb399c273c.png">
### After, on this PR
<img width="932" alt="Screenshot 2022-08-22 at 15 12 11" src="https://user-images.githubusercontent.com/302146/185965420-8be493e2-3b1a-4188-bd13-fd6b17a76fe7.png">
### Double-sided material without normal maps
https://user-images.githubusercontent.com/302146/185988113-44a384e7-0b55-4946-9b99-20f8c803ab7e.mp4
---
## Changelog
- Fixed: Lighting of normal-mapped, double-sided materials applied to models with negative scale
- Fixed: Lighting and shadowing of back faces with no normal-mapping and a double-sided material
## Migration Guide
`prepare_normal` from the `bevy_pbr::pbr_functions` shader import has been reworked.
Before:
```rust
pbr_input.world_normal = in.world_normal;
pbr_input.N = prepare_normal(
pbr_input.material.flags,
in.world_normal,
#ifdef VERTEX_TANGENTS
#ifdef STANDARDMATERIAL_NORMAL_MAP
in.world_tangent,
#endif
#endif
in.uv,
in.is_front,
);
```
After:
```rust
pbr_input.world_normal = prepare_world_normal(
in.world_normal,
(material.flags & STANDARD_MATERIAL_FLAGS_DOUBLE_SIDED_BIT) != 0u,
in.is_front,
);
pbr_input.N = apply_normal_mapping(
pbr_input.material.flags,
pbr_input.world_normal,
#ifdef VERTEX_TANGENTS
#ifdef STANDARDMATERIAL_NORMAL_MAP
in.world_tangent,
#endif
#endif
in.uv,
);
```
# Objective
Currently we are limiting the amount of direction lights in a scene to one.
## Solution
Increase the amount of direction lights from 1 to 10.
This still is not a perfect solution, but should unblock many use cases.
We could probably just store the directional lights similar to the point lights in an storage buffer, allowing for an variable amount of directional lights.
Co-authored-by: Kurt Kühnert <51823519+Ku95@users.noreply.github.com>
This reverts commit 53d387f340.
# Objective
Reverts #6448. This didn't have the intended effect: we're now getting bevy::prelude shown in the docs again.
Co-authored-by: Alejandro Pascual <alejandro.pascual.pozo@gmail.com>
# Objective
- Right now re-exports are completely hidden in prelude docs.
- Fixes#6433
## Solution
- We could show the re-exports without inlining their documentation.
# Objective
- Add post processing passes for FXAA (Fast Approximate Anti-Aliasing)
- Add example comparing MSAA and FXAA
## Solution
When the FXAA plugin is added, passes for FXAA are inserted between the main pass and the tonemapping pass. Supports using either HDR or LDR output from the main pass.
---
## Changelog
- Add a new FXAANode that runs after the main pass when the FXAA plugin is added.
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
- Freeing unused memory held by visible entities
- Fixed comment style
# Objective
With Rust 1.56 it's possible to shrink vectors to a specified capacity. Visibility system had a comment before asking for that feature to free unused memory by a vector if its capacity is two times larger than the length.
## Solution
Shrinking the vector of visible entities to the nearest power of 2 elements next to `len()`, if capacity exceeds it more than two times.
# Objective
Bevy still has many instances of using single-tuples `(T,)` to create a bundle. Due to #2975, this is no longer necessary.
## Solution
Search for regex `\(.+\s*,\)`. This should have found every instance.
# Objective
- fix new clippy lints before they get stable and break CI
## Solution
- run `clippy --fix` to auto-fix machine-applicable lints
- silence `clippy::should_implement_trait` for `fn HandleId::default<T: Asset>`
## Changes
- always prefer `format!("{inline}")` over `format!("{}", not_inline)`
- prefer `Box::default` (or `Box::<T>::default` if necessary) over `Box::new(T::default())`
# Objective
![image](https://user-images.githubusercontent.com/22177966/189350194-639a0211-e984-4f73-ae62-0ede44891eb9.png)
^ enable this
Concretely, I need to
- list all handle ids for an asset type
- fetch the asset as `dyn Reflect`, given a `HandleUntyped`
- when encountering a `Handle<T>`, find out what asset type that handle refers to (`T`'s type id) and turn the handle into a `HandleUntyped`
## Solution
- add `ReflectAsset` type containing function pointers for working with assets
```rust
pub struct ReflectAsset {
type_uuid: Uuid,
assets_resource_type_id: TypeId, // TypeId of the `Assets<T>` resource
get: fn(&World, HandleUntyped) -> Option<&dyn Reflect>,
get_mut: fn(&mut World, HandleUntyped) -> Option<&mut dyn Reflect>,
get_unchecked_mut: unsafe fn(&World, HandleUntyped) -> Option<&mut dyn Reflect>,
add: fn(&mut World, &dyn Reflect) -> HandleUntyped,
set: fn(&mut World, HandleUntyped, &dyn Reflect) -> HandleUntyped,
len: fn(&World) -> usize,
ids: for<'w> fn(&'w World) -> Box<dyn Iterator<Item = HandleId> + 'w>,
remove: fn(&mut World, HandleUntyped) -> Option<Box<dyn Reflect>>,
}
```
- add `ReflectHandle` type relating the handle back to the asset type and providing a way to create a `HandleUntyped`
```rust
pub struct ReflectHandle {
type_uuid: Uuid,
asset_type_id: TypeId,
downcast_handle_untyped: fn(&dyn Any) -> Option<HandleUntyped>,
}
```
- add the corresponding `FromType` impls
- add a function `app.register_asset_reflect` which is supposed to be called after `.add_asset` and registers `ReflectAsset` and `ReflectHandle` in the type registry
---
## Changelog
- add `ReflectAsset` and `ReflectHandle` types, which allow code to use reflection to manipulate arbitrary assets without knowing their types at compile time
# Objective
Bevy's internal plugins have lots of execution-order ambiguities, which makes the ambiguity detection tool very noisy for our users.
## Solution
Silence every last ambiguity that can currently be resolved.
Each time an ambiguity is silenced, it is accompanied by a comment describing why it is correct. This description should be based on the public API of the respective systems. Thus, I have added documentation to some systems describing how they use some resources.
# Future work
Some ambiguities remain, due to issues out of scope for this PR.
* The ambiguity checker does not respect `Without<>` filters, leading to false positives.
* Ambiguities between `bevy_ui` and `bevy_animation` cannot be resolved, since neither crate knows that the other exists. We will need a general solution to this problem.
Attempt to make features like bloom https://github.com/bevyengine/bevy/pull/2876 easier to implement.
**This PR:**
- Moves the tonemapping from `pbr.wgsl` into a separate pass
- also add a separate upscaling pass after the tonemapping which writes to the swap chain (enables resolution-independant rendering and post-processing after tonemapping)
- adds a `hdr` bool to the camera which controls whether the pbr and sprite shaders render into a `Rgba16Float` texture
**Open questions:**
- ~should the 2d graph work the same as the 3d one?~ it is the same now
- ~The current solution is a bit inflexible because while you can add a post processing pass that writes to e.g. the `hdr_texture`, you can't write to a separate `user_postprocess_texture` while reading the `hdr_texture` and tell the tone mapping pass to read from the `user_postprocess_texture` instead. If the tonemapping and upscaling render graph nodes were to take in a `TextureView` instead of the view entity this would almost work, but the bind groups for their respective input textures are already created in the `Queue` render stage in the hardcoded order.~ solved by creating bind groups in render node
**New render graph:**
![render_graph](https://user-images.githubusercontent.com/22177966/147767249-57dd4229-cfab-4ec5-9bf3-dc76dccf8e8b.png)
<details>
<summary>Before</summary>
![render_graph_old](https://user-images.githubusercontent.com/22177966/147284579-c895fdbd-4028-41cf-914c-e1ffef60e44e.png)
</details>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Improve ergonomics by passing on the `IntoIterator` impl of the underlying type to wrapper types.
## Solution
Implement `IntoIterator` for ECS wrapper types (Mut, Local, Res, etc.).
Co-authored-by: devil-ira <justthecooldude@gmail.com>
# Objective
Use saturate wgsl function now implemented in naga (version 0.10.0). There is now no need for one in utils.wgsl.
naga's version allows usage for not only scalars but vectors as well.
## Solution
Remove the utils.wgsl saturate function.
## Changelog
Remove saturate function from utils.wgsl in favor of saturate in naga v0.10.0.
# Objective
- It's possible to create a mesh without positions or normals, but currently bevy forces these attributes to be present on any mesh.
## Solution
- Don't assume these attributes are present and add a shader defs for each attributes
- I updated 2d and 3d meshes to use the same logic.
---
## Changelog
- Meshes don't require any attributes
# Notes
I didn't update the pbr.wgsl shader because I'm not sure how to handle it. It doesn't really make sense to use it without positions or normals.
# Objective
There is no Srgb support on some GPU and display protocols with `winit` (for example, Nvidia's GPUs with Wayland). Thus `TextureFormat::bevy_default()` which returns `Rgba8UnormSrgb` or `Bgra8UnormSrgb` will cause panics on such platforms. This patch will resolve this problem. Fix https://github.com/bevyengine/bevy/issues/3897.
## Solution
Make `initialize_renderer` expose `wgpu::Adapter` and `first_available_texture_format`, use the `first_available_texture_format` by default.
## Changelog
* Fixed https://github.com/bevyengine/bevy/issues/3897.
# Objective
fix error with pbr shader's spotlight direction calculation when direction.y ~= 0
## Solution
in pbr_lighting.wgsl, clamp `1-x^2-z^2` to `>= 0` so that we can safely `sqrt` it
# Objective
The `Wireframe` type implements `Reflect`, but is never registered, making its reflection inaccessible.
## Solution
Call `App::register_type::<Wireframe>()` in the `Plugin::build` implementation of `WireframePlugin`.
---
## Changelog
Fixed `Wireframe` type reflection not getting registered.
# Objective
Add more documentation on `StandardMaterial` and improve
consistency on existing doc.
Co-authored-by: Nicola Papale <nicopap@users.noreply.github.com>
# Objective
- Alpha mask was previously ignored when using an unlit material.
- Fixes https://github.com/bevyengine/bevy/issues/4479
## Solution
- Extract the alpha discard to a separate function and use it when unlit is true
## Notes
I tried calling `alpha_discard()` before the `if` in pbr.wgsl, but I had errors related to having a `discard` at the beginning before doing the texture sampling. I'm not sure if there's a way to fix that instead of having the function being called in 2 places.
# Objective
Simple docs/comments only PR that just fixes some outdated file references left over from the render rewrite.
## Solution
- Change the references to point to the correct files
# Objective
The [Stageless RFC](https://github.com/bevyengine/rfcs/pull/45) involves allowing exclusive systems to be referenced and ordered relative to parallel systems. We've agreed that unifying systems under `System` is the right move.
This is an alternative to #4166 (see rationale in the comments I left there). Note that this builds on the learnings established there (and borrows some patterns).
## Solution
This unifies parallel and exclusive systems under the shared `System` trait, removing the old `ExclusiveSystem` trait / impls. This is accomplished by adding a new `ExclusiveFunctionSystem` impl similar to `FunctionSystem`. It is backed by `ExclusiveSystemParam`, which is similar to `SystemParam`. There is a new flattened out SystemContainer api (which cuts out a lot of trait and type complexity).
This means you can remove all cases of `exclusive_system()`:
```rust
// before
commands.add_system(some_system.exclusive_system());
// after
commands.add_system(some_system);
```
I've also implemented `ExclusiveSystemParam` for `&mut QueryState` and `&mut SystemState`, which makes this possible in exclusive systems:
```rust
fn some_exclusive_system(
world: &mut World,
transforms: &mut QueryState<&Transform>,
state: &mut SystemState<(Res<Time>, Query<&Player>)>,
) {
for transform in transforms.iter(world) {
println!("{transform:?}");
}
let (time, players) = state.get(world);
for player in players.iter() {
println!("{player:?}");
}
}
```
Note that "exclusive function systems" assume `&mut World` is present (and the first param). I think this is a fair assumption, given that the presence of `&mut World` is what defines the need for an exclusive system.
I added some targeted SystemParam `static` constraints, which removed the need for this:
``` rust
fn some_exclusive_system(state: &mut SystemState<(Res<'static, Time>, Query<&'static Player>)>) {}
```
## Related
- #2923
- #3001
- #3946
## Changelog
- `ExclusiveSystem` trait (and implementations) has been removed in favor of sharing the `System` trait.
- `ExclusiveFunctionSystem` and `ExclusiveSystemParam` were added, enabling flexible exclusive function systems
- `&mut SystemState` and `&mut QueryState` now implement `ExclusiveSystemParam`
- Exclusive and parallel System configuration is now done via a unified `SystemDescriptor`, `IntoSystemDescriptor`, and `SystemContainer` api.
## Migration Guide
Calling `.exclusive_system()` is no longer required (or supported) for converting exclusive system functions to exclusive systems:
```rust
// Old (0.8)
app.add_system(some_exclusive_system.exclusive_system());
// New (0.9)
app.add_system(some_exclusive_system);
```
Converting "normal" parallel systems to exclusive systems is done by calling the exclusive ordering apis:
```rust
// Old (0.8)
app.add_system(some_system.exclusive_system().at_end());
// New (0.9)
app.add_system(some_system.at_end());
```
Query state in exclusive systems can now be cached via ExclusiveSystemParams, which should be preferred for clarity and performance reasons:
```rust
// Old (0.8)
fn some_system(world: &mut World) {
let mut transforms = world.query::<&Transform>();
for transform in transforms.iter(world) {
}
}
// New (0.9)
fn some_system(world: &mut World, transforms: &mut QueryState<&Transform>) {
for transform in transforms.iter(world) {
}
}
```
# 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%:
![image](https://user-images.githubusercontent.com/2694663/191627587-4ab2f949-4ccd-4231-80eb-80dd4d9ad6b9.png)
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();
```