# Objective
- Mesh entities should cast shadows when not having Aabbs and having
NoFrustumCulling
- Fixes#8442
## Solution
- Mesh entities with NoFrustumCulling get no automatic Aabbs added
- Point and spot lights do not cull mesh entities for their shadow
mapping if they do not have an Aabb, but directional lights do
- Make directional lights not cull mesh entities from cascades if the do
not have Aabbs. So no Aabb as a consequence of a NoFrustumCulling
component will mean that those mesh entities are not culled and so are
visible to the light.
---
## Changelog
- Fixed: Mesh entities with NoFrustumCulling will cast shadows for
directional light shadow maps
# Objective
The default StandardMaterial values of `pbr_material.rs` and
`pbr_types.wgsl` are out of sync.
I think they are out of sync since
https://github.com/bevyengine/bevy/pull/7664.
## Solution
Adapt the values: `metallic = 0.0`, `perceptual_roughness = 0.5`.
Fixes issue mentioned in PR #8285.
_Note: By mistake, this is currently dependent on #8285_
# Objective
Ensure consistency in the spelling of the documentation.
Exceptions:
`crates/bevy_mikktspace/src/generated.rs` - Has not been changed from
licence to license as it is part of a licensing agreement.
Maybe for further consistency,
https://github.com/bevyengine/bevy-website should also be given a look.
## Solution
### Changed the spelling of the current words (UK/CN/AU -> US) :
cancelled -> canceled (Breaking API changes in #8285)
behaviour -> behavior (Breaking API changes in #8285)
neighbour -> neighbor
grey -> gray
recognise -> recognize
centre -> center
metres -> meters
colour -> color
### ~~Update [`engine_style_guide.md`]~~ Moved to #8324
---
## Changelog
Changed UK spellings in documentation to US
## Migration Guide
Non-breaking changes*
\* If merged after #8285
# Objective
The clippy lint `type_complexity` is known not to play well with bevy.
It frequently triggers when writing complex queries, and taking the
lint's advice of using a type alias almost always just obfuscates the
code with no benefit. Because of this, this lint is currently ignored in
CI, but unfortunately it still shows up when viewing bevy code in an
IDE.
As someone who's made a fair amount of pull requests to this repo, I
will say that this issue has been a consistent thorn in my side. Since
bevy code is filled with spurious, ignorable warnings, it can be very
difficult to spot the *real* warnings that must be fixed -- most of the
time I just ignore all warnings, only to later find out that one of them
was real after I'm done when CI runs.
## Solution
Suppress this lint in all bevy crates. This was previously attempted in
#7050, but the review process ended up making it more complicated than
it needs to be and landed on a subpar solution.
The discussion in https://github.com/rust-lang/rust-clippy/pull/10571
explores some better long-term solutions to this problem. Since there is
no timeline on when these solutions may land, we should resolve this
issue in the meantime by locally suppressing these lints.
### Unresolved issues
Currently, these lints are not suppressed in our examples, since that
would require suppressing the lint in every single source file. They are
still ignored in CI.
# Objective
- Closes https://github.com/bevyengine/bevy/issues/8008
## Solution
- Add a skybox plugin that renders a fullscreen triangle, and then
modifies the vertices in a vertex shader to enforce that it renders as a
skybox background.
- Skybox is run at the end of MainOpaquePass3dNode.
- In the future, it would be nice to get something like bevy_atmosphere
built-in, and have a default skybox+environment map light.
---
## Changelog
- Added `Skybox`.
- `EnvironmentMapLight` now renders in the correct orientation.
## Migration Guide
- Flip `EnvironmentMapLight` maps if needed to match how they previously
rendered (which was backwards).
---------
Co-authored-by: Robert Swain <robert.swain@gmail.com>
Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com>
# Objective
- We support enabling a normal prepass, but the main pass never actually
uses it and recomputes the normals in the main pass. This isn't ideal
since it's doing redundant work.
## Solution
- Use the normal texture from the prepass in the main pass
## Notes
~~I used `NORMAL_PREPASS_ENABLED` as a shader_def because
`NORMAL_PREPASS` is currently used to signify that it is running in the
prepass while this shader_def need to indicate the prepass is done and
the normal prepass was ran before. I'm not sure if there's a better way
to name this.~~
# Objective
Fixes#8089.
## Solution
Splits the MainPass3dNode into 2 nodes, one for the opaque + alpha
passes and one for the transparent pass.
---
## Changelog
- Split MainPass3dNode into MainOpaquePass3dNode and
MainTransparentPass3dNode
- Combine opaque and alpha phases in MainOpaquePass3dNode into one pass
- Create `START_MAIN_PASS` and `END_MAIN_PASS` empty nodes as labels
- Main pass becomes `START_MAIN_PASS -> MAIN_OPAQUE_PASS ->
MAIN_TRANSPARENT_PASS -> END_MAIN_PASS`
## Migration Guide
Nodes that previously added edges involving `MAIN_PASS` should now add
edges to or from `START_MAIN_PASS` or `END_MAIN_PASS` respectively.
# Objective
- Implement an alternative antialias technique
- TAA scales based off of view resolution, not geometry complexity
- TAA filters textures, firefly pixels, and other aliasing not covered
by MSAA
- TAA additionally will reduce noise / increase quality in future
stochastic rendering techniques
- Closes https://github.com/bevyengine/bevy/issues/3663
## Solution
- Add a temporal jitter component
- Add a motion vector prepass
- Add a TemporalAntialias component and plugin
- Combine existing MSAA and FXAA examples and add TAA
## Followup Work
- Prepass motion vector support for skinned meshes
- Move uniforms needed for motion vectors into a separate bind group,
instead of using different bind group layouts
- Reuse previous frame's GPU view buffer for motion vectors, instead of
recomputing
- Mip biasing for sharper textures, and or unjitter texture UVs
https://github.com/bevyengine/bevy/issues/7323
- Compute shader for better performance
- Investigate FSR techniques
- Historical depth based disocclusion tests, for geometry disocclusion
- Historical luminance/hue based tests, for shading disocclusion
- Pixel "locks" to reduce blending rate / revamp history confidence
mechanism
- Orthographic camera support for TemporalJitter
- Figure out COD's 1-tap bicubic filter
---
## Changelog
- Added MotionVectorPrepass and TemporalJitter
- Added TemporalAntialiasPlugin, TemporalAntialiasBundle, and
TemporalAntialiasSettings
---------
Co-authored-by: IceSentry <c.giguere42@gmail.com>
Co-authored-by: IceSentry <IceSentry@users.noreply.github.com>
Co-authored-by: Robert Swain <robert.swain@gmail.com>
Co-authored-by: Daniel Chia <danstryder@gmail.com>
Co-authored-by: robtfm <50659922+robtfm@users.noreply.github.com>
Co-authored-by: Brandon Dyer <brandondyer64@gmail.com>
Co-authored-by: Edgar Geier <geieredgar@gmail.com>
- Fixes#7965
- Code quality improvements.
- Removes the unreferenced function `dither` in pbr_functions.wgsl
introduced in 72fbcc7, but made obsolete in c069c54.
- Makes the reference to `screen_space_dither` in pbr.wgsl conditional
on `#ifdef TONEMAP_IN_SHADER`, as the required import is conditional on
the same, as deband dithering can only occur if tonemapping is also
occurring.
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
- Currently, the render graph slots are only used to pass the
view_entity around. This introduces significant boilerplate for very
little value. Instead of using slots for this, make the view_entity part
of the `RenderGraphContext`. This also means we won't need to have
`IN_VIEW` on every node and and we'll be able to use the default impl of
`Node::input()`.
## Solution
- Add `view_entity: Option<Entity>` to the `RenderGraphContext`
- Update all nodes to use this instead of entity slot input
---
## Changelog
- Add optional `view_entity` to `RenderGraphContext`
## Migration Guide
You can now get the view_entity directly from the `RenderGraphContext`.
When implementing the Node:
```rust
// 0.10
struct FooNode;
impl FooNode {
const IN_VIEW: &'static str = "view";
}
impl Node for FooNode {
fn input(&self) -> Vec<SlotInfo> {
vec![SlotInfo::new(Self::IN_VIEW, SlotType::Entity)]
}
fn run(
&self,
graph: &mut RenderGraphContext,
// ...
) -> Result<(), NodeRunError> {
let view_entity = graph.get_input_entity(Self::IN_VIEW)?;
// ...
Ok(())
}
}
// 0.11
struct FooNode;
impl Node for FooNode {
fn run(
&self,
graph: &mut RenderGraphContext,
// ...
) -> Result<(), NodeRunError> {
let view_entity = graph.view_entity();
// ...
Ok(())
}
}
```
When adding the node to the graph, you don't need to specify a slot_edge
for the view_entity.
```rust
// 0.10
let mut graph = RenderGraph::default();
graph.add_node(FooNode::NAME, node);
let input_node_id = draw_2d_graph.set_input(vec![SlotInfo::new(
graph::input::VIEW_ENTITY,
SlotType::Entity,
)]);
graph.add_slot_edge(
input_node_id,
graph::input::VIEW_ENTITY,
FooNode::NAME,
FooNode::IN_VIEW,
);
// add_node_edge ...
// 0.11
let mut graph = RenderGraph::default();
graph.add_node(FooNode::NAME, node);
// add_node_edge ...
```
## Notes
This PR paired with #8007 will help reduce a lot of annoying boilerplate
with the render nodes. Depending on which one gets merged first. It will
require a bit of clean up work to make both compatible.
I tagged this as a breaking change, because using the old system to get
the view_entity will break things because it's not a node input slot
anymore.
## Notes for reviewers
A lot of the diffs are just removing the slots in every nodes and graph
creation. The important part is mostly in the
graph_runner/CameraDriverNode.
# 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)
(After)
# 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**
**After**
# 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
