This reverts commit 0b5302d96a.
# Objective
- Fixes#18158
- #17482 introduced rendering changes and was merged a bit too fast
## Solution
- Revert #17482 so that it can be redone and rendering changes discussed
before being merged. This will make it easier to compare changes with
main in the known "valid" state
This is not an issue with the work done in #17482 that is still
interesting
# Objective
Transparently uses simple `EnvironmentMapLight`s to mimic
`AmbientLight`s. Implements the first part of #17468, but I can
implement hemispherical lights in this PR too if needed.
## Solution
- A function `EnvironmentMapLight::solid_color(&mut Assets<Image>,
Color)` is provided to make an environment light with a solid color.
- A new system is added to `SimulationLightSystems` that maps
`AmbientLight`s on views or the world to a corresponding
`EnvironmentMapLight`.
I have never worked with (or on) Bevy before, so nitpicky comments on
how I did things are appreciated :).
## Testing
Testing was done on a modified version of the `3d/lighting` example,
where I removed all lights except the ambient light. I have not included
the example, but can if required.
## Migration
`bevy_pbr::AmbientLight` has been deprecated, so all usages of it should
be replaced by a `bevy_pbr::EnvironmentMapLight` created with
`EnvironmentMapLight::solid_color` placed on the camera. There is no
alternative to ambient lights as resources.
This PR adds support for *mixed lighting* to Bevy, whereby some parts of
the scene are lightmapped, while others take part in real-time lighting.
(Here *real-time lighting* means lighting at runtime via the PBR shader,
as opposed to precomputed light using lightmaps.) It does so by adding a
new field, `affects_lightmapped_meshes` to `IrradianceVolume` and
`AmbientLight`, and a corresponding field
`affects_lightmapped_mesh_diffuse` to `DirectionalLight`, `PointLight`,
`SpotLight`, and `EnvironmentMapLight`. By default, this value is set to
true; when set to false, the light contributes nothing to the diffuse
irradiance component to meshes with lightmaps.
Note that specular light is unaffected. This is because the correct way
to bake specular lighting is *directional lightmaps*, which we have no
support for yet.
There are two general ways I expect this field to be used:
1. When diffuse indirect light is baked into lightmaps, irradiance
volumes and reflection probes shouldn't contribute any diffuse light to
the static geometry that has a lightmap. That's because the baking tool
should have already accounted for it, and in a higher-quality fashion,
as lightmaps typically offer a higher effective texture resolution than
the light probe does.
2. When direct diffuse light is baked into a lightmap, punctual lights
shouldn't contribute any diffuse light to static geometry with a
lightmap, to avoid double-counting. It may seem odd to bake *direct*
light into a lightmap, as opposed to indirect light. But there is a use
case: in a scene with many lights, avoiding light leaks requires shadow
mapping, which quickly becomes prohibitive when many lights are
involved. Baking lightmaps allows light leaks to be eliminated on static
geometry.
A new example, `mixed_lighting`, has been added. It demonstrates a sofa
(model from the [glTF Sample Assets]) that has been lightmapped offline
using [Bakery]. It has four modes:
1. In *baked* mode, all objects are locked in place, and all the diffuse
direct and indirect light has been calculated ahead of time. Note that
the bottom of the sphere has a red tint from the sofa, illustrating that
the baking tool captured indirect light for it.
2. In *mixed direct* mode, lightmaps capturing diffuse direct and
indirect light have been pre-calculated for the static objects, but the
dynamic sphere has real-time lighting. Note that, because the diffuse
lighting has been entirely pre-calculated for the scenery, the dynamic
sphere casts no shadow. In a real app, you would typically use real-time
lighting for the most important light so that dynamic objects can shadow
the scenery and relegate baked lighting to the less important lights for
which shadows aren't as important. Also note that there is no red tint
on the sphere, because there is no global illumination applied to it. In
an actual game, you could fix this problem by supplementing the
lightmapped objects with an irradiance volume.
3. In *mixed indirect* mode, all direct light is calculated in
real-time, and the static objects have pre-calculated indirect lighting.
This corresponds to the mode that most applications are expected to use.
Because direct light on the scenery is computed dynamically, shadows are
fully supported. As in mixed direct mode, there is no global
illumination on the sphere; in a real application, irradiance volumes
could be used to supplement the lightmaps.
4. In *real-time* mode, no lightmaps are used at all, and all punctual
lights are rendered in real-time. No global illumination exists.
In the example, you can click around to move the sphere, unless you're
in baked mode, in which case the sphere must be locked in place to be
lit correctly.
## Showcase
Baked mode:

Mixed direct mode:

Mixed indirect mode (default):

Real-time mode:

## Migration guide
* The `AmbientLight` resource, the `IrradianceVolume` component, and the
`EnvironmentMapLight` component now have `affects_lightmapped_meshes`
fields. If you don't need to use that field (for example, if you aren't
using lightmaps), you can safely set the field to true.
* `DirectionalLight`, `PointLight`, and `SpotLight` now have
`affects_lightmapped_mesh_diffuse` fields. If you don't need to use that
field (for example, if you aren't using lightmaps), you can safely set
the field to true.
[glTF Sample Assets]:
https://github.com/KhronosGroup/glTF-Sample-Assets/tree/main
[Bakery]:
https://geom.io/bakery/wiki/index.php?title=Bakery_-_GPU_Lightmapper
# Objective
Continue improving the user experience of our UI Node API in the
direction specified by [Bevy's Next Generation Scene / UI
System](https://github.com/bevyengine/bevy/discussions/14437)
## Solution
As specified in the document above, merge `Style` fields into `Node`,
and move "computed Node fields" into `ComputedNode` (I chose this name
over something like `ComputedNodeLayout` because it currently contains
more than just layout info. If we want to break this up / rename these
concepts, lets do that in a separate PR). `Style` has been removed.
This accomplishes a number of goals:
## Ergonomics wins
Specifying both `Node` and `Style` is now no longer required for
non-default styles
Before:
```rust
commands.spawn((
Node::default(),
Style {
width: Val::Px(100.),
..default()
},
));
```
After:
```rust
commands.spawn(Node {
width: Val::Px(100.),
..default()
});
```
## Conceptual clarity
`Style` was never a comprehensive "style sheet". It only defined "core"
style properties that all `Nodes` shared. Any "styled property" that
couldn't fit that mold had to be in a separate component. A "real" style
system would style properties _across_ components (`Node`, `Button`,
etc). We have plans to build a true style system (see the doc linked
above).
By moving the `Style` fields to `Node`, we fully embrace `Node` as the
driving concept and remove the "style system" confusion.
## Next Steps
* Consider identifying and splitting out "style properties that aren't
core to Node". This should not happen for Bevy 0.15.
---
## Migration Guide
Move any fields set on `Style` into `Node` and replace all `Style`
component usage with `Node`.
Before:
```rust
commands.spawn((
Node::default(),
Style {
width: Val::Px(100.),
..default()
},
));
```
After:
```rust
commands.spawn(Node {
width: Val::Px(100.),
..default()
});
```
For any usage of the "computed node properties" that used to live on
`Node`, use `ComputedNode` instead:
Before:
```rust
fn system(nodes: Query<&Node>) {
for node in &nodes {
let computed_size = node.size();
}
}
```
After:
```rust
fn system(computed_nodes: Query<&ComputedNode>) {
for computed_node in &computed_nodes {
let computed_size = computed_node.size();
}
}
```
Fixes#15834
## Migration Guide
The APIs of `Time`, `Timer` and `Stopwatch` have been cleaned up for
consistency with each other and the standard library's `Duration` type.
The following methods have been renamed:
- `Stowatch::paused` -> `Stopwatch::is_paused`
- `Time::elapsed_seconds` -> `Time::elasped_secs` (including `_f64` and
`_wrapped` variants)
# Objective
- closes#15866
## Solution
- Simply migrate where possible.
## Testing
- Expect that CI will do most of the work. Examples is another way of
testing this, as most of the work is in that area.
---
## Notes
For now, this PR doesn't migrate `QueryState::single` and friends as for
now, this look like another issue. So for example, QueryBuilders that
used single or `World::query` that used single wasn't migrated. If there
is a easy way to migrate those, please let me know.
Most of the uses of `Query::single` were removed, the only other uses
that I found was related to tests of said methods, so will probably be
removed when we remove `Query::single`.
# Objective
Currently text is recomputed unnecessarily on any changes to its color,
which is extremely expensive.
## Solution
Split up `TextStyle` into two separate components `TextFont` and
`TextColor`.
## Testing
I added this system to `many_buttons`:
```rust
fn set_text_colors_changed(mut colors: Query<&mut TextColor>) {
for mut text_color in colors.iter_mut() {
text_color.set_changed();
}
}
```
reports ~4fps on main, ~50fps with this PR.
## Migration Guide
`TextStyle` has been renamed to `TextFont` and its `color` field has
been moved to a separate component named `TextColor` which newtypes
`Color`.
# Objective
Fixes#15824
## Solution
Looks like this was just a goof in migrating the example itself.
Added back in the rotation component of the transform that got dropped.
## Testing
`cargo run --example auto_exposure`
**Ready for review. Examples migration progress: 100%.**
# Objective
- Implement https://github.com/bevyengine/bevy/discussions/15014
## Solution
This implements [cart's
proposal](https://github.com/bevyengine/bevy/discussions/15014#discussioncomment-10574459)
faithfully except for one change. I separated `TextSpan` from
`TextSpan2d` because `TextSpan` needs to require the `GhostNode`
component, which is a `bevy_ui` component only usable by UI.
Extra changes:
- Added `EntityCommands::commands_mut` that returns a mutable reference.
This is a blocker for extension methods that return something other than
`self`. Note that `sickle_ui`'s `UiBuilder::commands` returns a mutable
reference for this reason.
## Testing
- [x] Text examples all work.
---
## Showcase
TODO: showcase-worthy
## Migration Guide
TODO: very breaking
### Accessing text spans by index
Text sections are now text sections on different entities in a
hierarchy, Use the new `TextReader` and `TextWriter` system parameters
to access spans by index.
Before:
```rust
fn refresh_text(mut query: Query<&mut Text, With<TimeText>>, time: Res<Time>) {
let text = query.single_mut();
text.sections[1].value = format_time(time.elapsed());
}
```
After:
```rust
fn refresh_text(
query: Query<Entity, With<TimeText>>,
mut writer: UiTextWriter,
time: Res<Time>
) {
let entity = query.single();
*writer.text(entity, 1) = format_time(time.elapsed());
}
```
### Iterating text spans
Text spans are now entities in a hierarchy, so the new `UiTextReader`
and `UiTextWriter` system parameters provide ways to iterate that
hierarchy. The `UiTextReader::iter` method will give you a normal
iterator over spans, and `UiTextWriter::for_each` lets you visit each of
the spans.
---------
Co-authored-by: ickshonpe <david.curthoys@googlemail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Yet another PR for migrating stuff to required components. This time,
cameras!
## Solution
As per the [selected
proposal](https://hackmd.io/tsYID4CGRiWxzsgawzxG_g#Combined-Proposal-1-Selected),
deprecate `Camera2dBundle` and `Camera3dBundle` in favor of `Camera2d`
and `Camera3d`.
Adding a `Camera` without `Camera2d` or `Camera3d` now logs a warning,
as suggested by Cart [on
Discord](https://discord.com/channels/691052431525675048/1264881140007702558/1291506402832945273).
I would personally like cameras to work a bit differently and be split
into a few more components, to avoid some footguns and confusing
semantics, but that is more controversial, and shouldn't block this core
migration.
## Testing
I ran a few 2D and 3D examples, and tried cameras with and without
render graphs.
---
## Migration Guide
`Camera2dBundle` and `Camera3dBundle` have been deprecated in favor of
`Camera2d` and `Camera3d`. Inserting them will now also insert the other
components required by them automatically.
# Objective
A big step in the migration to required components: meshes and
materials!
## Solution
As per the [selected
proposal](https://hackmd.io/@bevy/required_components/%2Fj9-PnF-2QKK0on1KQ29UWQ):
- Deprecate `MaterialMesh2dBundle`, `MaterialMeshBundle`, and
`PbrBundle`.
- Add `Mesh2d` and `Mesh3d` components, which wrap a `Handle<Mesh>`.
- Add `MeshMaterial2d<M: Material2d>` and `MeshMaterial3d<M: Material>`,
which wrap a `Handle<M>`.
- Meshes *without* a mesh material should be rendered with a default
material. The existence of a material is determined by
`HasMaterial2d`/`HasMaterial3d`, which is required by
`MeshMaterial2d`/`MeshMaterial3d`. This gets around problems with the
generics.
Previously:
```rust
commands.spawn(MaterialMesh2dBundle {
mesh: meshes.add(Circle::new(100.0)).into(),
material: materials.add(Color::srgb(7.5, 0.0, 7.5)),
transform: Transform::from_translation(Vec3::new(-200., 0., 0.)),
..default()
});
```
Now:
```rust
commands.spawn((
Mesh2d(meshes.add(Circle::new(100.0))),
MeshMaterial2d(materials.add(Color::srgb(7.5, 0.0, 7.5))),
Transform::from_translation(Vec3::new(-200., 0., 0.)),
));
```
If the mesh material is missing, previously nothing was rendered. Now,
it renders a white default `ColorMaterial` in 2D and a
`StandardMaterial` in 3D (this can be overridden). Below, only every
other entity has a material:


Why white? This is still open for discussion, but I think white makes
sense for a *default* material, while *invalid* asset handles pointing
to nothing should have something like a pink material to indicate that
something is broken (I don't handle that in this PR yet). This is kind
of a mix of Godot and Unity: Godot just renders a white material for
non-existent materials, while Unity renders nothing when no materials
exist, but renders pink for invalid materials. I can also change the
default material to pink if that is preferable though.
## Testing
I ran some 2D and 3D examples to test if anything changed visually. I
have not tested all examples or features yet however. If anyone wants to
test more extensively, it would be appreciated!
## Implementation Notes
- The relationship between `bevy_render` and `bevy_pbr` is weird here.
`bevy_render` needs `Mesh3d` for its own systems, but `bevy_pbr` has all
of the material logic, and `bevy_render` doesn't depend on it. I feel
like the two crates should be refactored in some way, but I think that's
out of scope for this PR.
- I didn't migrate meshlets to required components yet. That can
probably be done in a follow-up, as this is already a huge PR.
- It is becoming increasingly clear to me that we really, *really* want
to disallow raw asset handles as components. They caused me a *ton* of
headache here already, and it took me a long time to find every place
that queried for them or inserted them directly on entities, since there
were no compiler errors for it. If we don't remove the `Component`
derive, I expect raw asset handles to be a *huge* footgun for users as
we transition to wrapper components, especially as handles as components
have been the norm so far. I personally consider this to be a blocker
for 0.15: we need to migrate to wrapper components for asset handles
everywhere, and remove the `Component` derive. Also see
https://github.com/bevyengine/bevy/issues/14124.
---
## Migration Guide
Asset handles for meshes and mesh materials must now be wrapped in the
`Mesh2d` and `MeshMaterial2d` or `Mesh3d` and `MeshMaterial3d`
components for 2D and 3D respectively. Raw handles as components no
longer render meshes.
Additionally, `MaterialMesh2dBundle`, `MaterialMeshBundle`, and
`PbrBundle` have been deprecated. Instead, use the mesh and material
components directly.
Previously:
```rust
commands.spawn(MaterialMesh2dBundle {
mesh: meshes.add(Circle::new(100.0)).into(),
material: materials.add(Color::srgb(7.5, 0.0, 7.5)),
transform: Transform::from_translation(Vec3::new(-200., 0., 0.)),
..default()
});
```
Now:
```rust
commands.spawn((
Mesh2d(meshes.add(Circle::new(100.0))),
MeshMaterial2d(materials.add(Color::srgb(7.5, 0.0, 7.5))),
Transform::from_translation(Vec3::new(-200., 0., 0.)),
));
```
If the mesh material is missing, a white default material is now used.
Previously, nothing was rendered if the material was missing.
The `WithMesh2d` and `WithMesh3d` query filter type aliases have also
been removed. Simply use `With<Mesh2d>` or `With<Mesh3d>`.
---------
Co-authored-by: Tim Blackbird <justthecooldude@gmail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Another step in the migration to required components: lights!
Note that this does not include `EnvironmentMapLight` or reflection
probes yet, because their API hasn't been fully chosen yet.
## Solution
As per the [selected
proposals](https://hackmd.io/@bevy/required_components/%2FLLnzwz9XTxiD7i2jiUXkJg):
- Deprecate `PointLightBundle` in favor of the `PointLight` component
- Deprecate `SpotLightBundle` in favor of the `PointLight` component
- Deprecate `DirectionalLightBundle` in favor of the `DirectionalLight`
component
## Testing
I ran some examples with lights.
---
## Migration Guide
`PointLightBundle`, `SpotLightBundle`, and `DirectionalLightBundle` have
been deprecated. Use the `PointLight`, `SpotLight`, and
`DirectionalLight` components instead. Adding them will now insert the
other components required by them automatically.
# Objective
The names of numerous rendering components in Bevy are inconsistent and
a bit confusing. Relevant names include:
- `AutoExposureSettings`
- `AutoExposureSettingsUniform`
- `BloomSettings`
- `BloomUniform` (no `Settings`)
- `BloomPrefilterSettings`
- `ChromaticAberration` (no `Settings`)
- `ContrastAdaptiveSharpeningSettings`
- `DepthOfFieldSettings`
- `DepthOfFieldUniform` (no `Settings`)
- `FogSettings`
- `SmaaSettings`, `Fxaa`, `TemporalAntiAliasSettings` (really
inconsistent??)
- `ScreenSpaceAmbientOcclusionSettings`
- `ScreenSpaceReflectionsSettings`
- `VolumetricFogSettings`
Firstly, there's a lot of inconsistency between `Foo`/`FooSettings` and
`FooUniform`/`FooSettingsUniform` and whether names are abbreviated or
not.
Secondly, the `Settings` post-fix seems unnecessary and a bit confusing
semantically, since it makes it seem like the component is mostly just
auxiliary configuration instead of the core *thing* that actually
enables the feature. This will be an even bigger problem once bundles
like `TemporalAntiAliasBundle` are deprecated in favor of required
components, as users will expect a component named `TemporalAntiAlias`
(or similar), not `TemporalAntiAliasSettings`.
## Solution
Drop the `Settings` post-fix from the component names, and change some
names to be more consistent.
- `AutoExposure`
- `AutoExposureUniform`
- `Bloom`
- `BloomUniform`
- `BloomPrefilter`
- `ChromaticAberration`
- `ContrastAdaptiveSharpening`
- `DepthOfField`
- `DepthOfFieldUniform`
- `DistanceFog`
- `Smaa`, `Fxaa`, `TemporalAntiAliasing` (note: we might want to change
to `Taa`, see "Discussion")
- `ScreenSpaceAmbientOcclusion`
- `ScreenSpaceReflections`
- `VolumetricFog`
I kept the old names as deprecated type aliases to make migration a bit
less painful for users. We should remove them after the next release.
(And let me know if I should just... not add them at all)
I also added some very basic docs for a few types where they were
missing, like on `Fxaa` and `DepthOfField`.
## Discussion
- `TemporalAntiAliasing` is still inconsistent with `Smaa` and `Fxaa`.
Consensus [on
Discord](https://discord.com/channels/691052431525675048/743663924229963868/1280601167209955431)
seemed to be that renaming to `Taa` would probably be fine, but I think
it's a bit more controversial, and it would've required renaming a lot
of related types like `TemporalAntiAliasNode`,
`TemporalAntiAliasBundle`, and `TemporalAntiAliasPlugin`, so I think
it's better to leave to a follow-up.
- I think `Fog` should probably have a more specific name like
`DistanceFog` considering it seems to be distinct from `VolumetricFog`.
~~This should probably be done in a follow-up though, so I just removed
the `Settings` post-fix for now.~~ (done)
---
## Migration Guide
Many rendering components have been renamed for improved consistency and
clarity.
- `AutoExposureSettings` → `AutoExposure`
- `BloomSettings` → `Bloom`
- `BloomPrefilterSettings` → `BloomPrefilter`
- `ContrastAdaptiveSharpeningSettings` → `ContrastAdaptiveSharpening`
- `DepthOfFieldSettings` → `DepthOfField`
- `FogSettings` → `DistanceFog`
- `SmaaSettings` → `Smaa`
- `TemporalAntiAliasSettings` → `TemporalAntiAliasing`
- `ScreenSpaceAmbientOcclusionSettings` → `ScreenSpaceAmbientOcclusion`
- `ScreenSpaceReflectionsSettings` → `ScreenSpaceReflections`
- `VolumetricFogSettings` → `VolumetricFog`
---------
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
Thought I had found all of these... noticed some `10px` in #15013 and
did another sweep.
Continuation of #8478, #13583.
## Solution
- Position example text (and other elements) 12px from the edge of the
screen
# Objective
Fixes#14782
## Solution
Enable the lint and fix all upcoming hints (`--fix`). Also tried to
figure out the false-positive (see review comment). Maybe split this PR
up into multiple parts where only the last one enables the lint, so some
can already be merged resulting in less many files touched / less
potential for merge conflicts?
Currently, there are some cases where it might be easier to read the
code with the qualifier, so perhaps remove the import of it and adapt
its cases? In the current stage it's just a plain adoption of the
suggestions in order to have a base to discuss.
## Testing
`cargo clippy` and `cargo run -p ci` are happy.
# Objective
- Fixes: https://github.com/bevyengine/bevy/issues/14036
## Solution
- Add a world space transformation for the environment sample direction.
## Testing
- I have tested the newly added `transform` field using the newly added
`rotate_environment_map` example.
https://github.com/user-attachments/assets/2de77c65-14bc-48ee-b76a-fb4e9782dbdb
## Migration Guide
- Since we have added a new filed to the `EnvironmentMapLight` struct,
users will need to include `..default()` or some rotation value in their
initialization code.
# Objective
- Fixes https://github.com/bevyengine/bevy/issues/14036
## Solution
- Add a view space transformation for the skybox
## Testing
- I have tested the newly added `transform` field using the `skybox`
example.
```
diff --git a/examples/3d/skybox.rs b/examples/3d/skybox.rs
index beaf5b268..d16cbe988 100644
--- a/examples/3d/skybox.rs
+++ b/examples/3d/skybox.rs
@@ -81,6 +81,7 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
Skybox {
image: skybox_handle.clone(),
brightness: 1000.0,
+ rotation: Quat::from_rotation_x(PI * -0.5),
},
));
```
<img width="1280" alt="image"
src="https://github.com/bevyengine/bevy/assets/6300263/1230a608-58ea-492d-a811-90c54c3b43ef">
## Migration Guide
- Since we have added a new filed to the Skybox struct, users will need
to include `..Default::default()` or some rotation value in their
initialization code.
# Objective
- The default font size is too small to be useful in examples or for
debug text.
- Fixes#13587
## Solution
- Updated the default font size value in `TextStyle` from 12px to 24px.
- Resorted to Text defaults in examples to use the default font size in
most of them.
## Testing
- WIP
---
## Migration Guide
- The default font size has been increased to 24px from 12px. Make sure
you set the font to the appropriate values in places you were using
`Default` text style.
## Objective
Use the "standard" text size / placement for the new text in these
examples.
Continuation of an effort started here:
https://github.com/bevyengine/bevy/pull/8478
This is definitely not comprehensive. I did the ones that were easy to
find and relatively straightforward updates. I meant to just do
`3d_shapes` and `2d_shapes`, but one thing lead to another.
## Solution
Use `font_size: 20.0`, the default (built-in) font, `Color::WHITE`
(default), and `Val::Px(12.)` from the edges of the screen.
There are a few little drive-by cleanups of defaults not being used,
etc.
## Testing
Ran the changed examples, verified that they still look reasonable.
# Objective
- In particularly dark scenes, auto-exposure would lead to an unexpected
darkening of the view.
- Fixes#13446.
## Solution
The average luminance should default to something else than 0.0 instead,
when there are no samples. We set it to `settings.min_log_lum`.
## Testing
I was able to reproduce the problem on the `auto_exposure` example by
setting the point light intensity to 2000 and looking into the
right-hand corner. There was a sudden darkening.
Now, the discontinuity is gone.
---------
Co-authored-by: Alice Cecile <alice.i.cecil@gmail.com>
Co-authored-by: Bram Buurlage <brambuurlage@gmail.com>
# Objective
- Add auto exposure/eye adaptation to the bevy render pipeline.
- Support features that users might expect from other engines:
- Metering masks
- Compensation curves
- Smooth exposure transitions
This PR is based on an implementation I already built for a personal
project before https://github.com/bevyengine/bevy/pull/8809 was
submitted, so I wasn't able to adopt that PR in the proper way. I've
still drawn inspiration from it, so @fintelia should be credited as
well.
## Solution
An auto exposure compute shader builds a 64 bin histogram of the scene's
luminance, and then adjusts the exposure based on that histogram. Using
a histogram allows the system to ignore outliers like shadows and
specular highlights, and it allows to give more weight to certain areas
based on a mask.
---
## Changelog
- Added: AutoExposure plugin that allows to adjust a camera's exposure
based on it's scene's luminance.
---------
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>