Commit graph

18 commits

Author SHA1 Message Date
Hamir Mahal
ec728c31c1
style: simplify string formatting for readability (#15033)
# Objective

The goal of this change is to improve code readability and
maintainability.
2024-09-03 23:35:49 +00:00
Chris Juchem
c620eb7833
Return Results from Camera's world/viewport conversion methods (#14989)
# Objective

- Fixes https://github.com/bevyengine/bevy/issues/14593.

## Solution

- Add `ViewportConversionError` and return it from viewport conversion
methods on Camera.

## Testing

- I successfully compiled and ran all changed examples.

## Migration Guide

The following methods on `Camera` now return a `Result` instead of an
`Option` so that they can provide more information about failures:
 - `world_to_viewport`
 - `world_to_viewport_with_depth`
 - `viewport_to_world`
 - `viewport_to_world_2d`

Call `.ok()` on the `Result` to turn it back into an `Option`, or handle
the `Result` directly.

---------

Co-authored-by: Lixou <82600264+DasLixou@users.noreply.github.com>
Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Zachary Harrold <zac@harrold.com.au>
2024-09-03 19:45:15 +00:00
Sou1gh0st
9da18cce2a
Add support for environment map transformation (#14290)
# 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.
2024-07-19 15:00:50 +00:00
Sou1gh0st
65aae92127
Add support for skybox transformation (#14267)
# 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.
2024-07-15 15:53:20 +00:00
Lura
856b39d821
Apply Clippy lints regarding lazy evaluation and closures (#14015)
# Objective

- Lazily evaluate
[default](https://rust-lang.github.io/rust-clippy/master/index.html#/unwrap_or_default)~~/[or](https://rust-lang.github.io/rust-clippy/master/index.html#/or_fun_call)~~
values where it makes sense
  - ~~`unwrap_or(foo())` -> `unwrap_or_else(|| foo())`~~
  - `unwrap_or(Default::default())` -> `unwrap_or_default()`
  - etc.
- Avoid creating [redundant
closures](https://rust-lang.github.io/rust-clippy/master/index.html#/redundant_closure),
even for [method
calls](https://rust-lang.github.io/rust-clippy/master/index.html#/redundant_closure_for_method_calls)
  - `map(|something| something.into())` -> `map(Into:into)`

## Solution

- Apply Clippy lints:
-
~~[or_fun_call](https://rust-lang.github.io/rust-clippy/master/index.html#/or_fun_call)~~
-
[unwrap_or_default](https://rust-lang.github.io/rust-clippy/master/index.html#/unwrap_or_default)
-
[redundant_closure_for_method_calls](https://rust-lang.github.io/rust-clippy/master/index.html#/redundant_closure_for_method_calls)
([redundant
closures](https://rust-lang.github.io/rust-clippy/master/index.html#/redundant_closure)
is already enabled)

## Testing

- Tested on Windows 11 (`stable-x86_64-pc-windows-gnu`, 1.79.0)
- Bevy compiles without errors or warnings and examples seem to work as
intended
  - `cargo clippy` 
  - `cargo run -p ci -- compile` 

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
2024-07-01 15:54:40 +00:00
Kornel
435d9bc02c
Highlight dependency on shader files in examples (#13824)
The examples won't work when copy-pasted to another project, without
also copying their shader files. This change adds constants at the top
of the files to bring attention to the dependencies.

Follow up to
[#13624](https://github.com/bevyengine/bevy/pull/13624#issuecomment-2143872791)
2024-06-12 14:16:01 +00:00
Ricky Taylor
9b9d3d81cb
Normalise matrix naming (#13489)
# Objective
- Fixes #10909
- Fixes #8492

## Solution
- Name all matrices `x_from_y`, for example `world_from_view`.

## Testing
- I've tested most of the 3D examples. The `lighting` example
particularly should hit a lot of the changes and appears to run fine.

---

## Changelog
- Renamed matrices across the engine to follow a `y_from_x` naming,
making the space conversion more obvious.

## Migration Guide
- `Frustum`'s `from_view_projection`, `from_view_projection_custom_far`
and `from_view_projection_no_far` were renamed to
`from_clip_from_world`, `from_clip_from_world_custom_far` and
`from_clip_from_world_no_far`.
- `ComputedCameraValues::projection_matrix` was renamed to
`clip_from_view`.
- `CameraProjection::get_projection_matrix` was renamed to
`get_clip_from_view` (this affects implementations on `Projection`,
`PerspectiveProjection` and `OrthographicProjection`).
- `ViewRangefinder3d::from_view_matrix` was renamed to
`from_world_from_view`.
- `PreviousViewData`'s members were renamed to `view_from_world` and
`clip_from_world`.
- `ExtractedView`'s `projection`, `transform` and `view_projection` were
renamed to `clip_from_view`, `world_from_view` and `clip_from_world`.
- `ViewUniform`'s `view_proj`, `unjittered_view_proj`,
`inverse_view_proj`, `view`, `inverse_view`, `projection` and
`inverse_projection` were renamed to `clip_from_world`,
`unjittered_clip_from_world`, `world_from_clip`, `world_from_view`,
`view_from_world`, `clip_from_view` and `view_from_clip`.
- `GpuDirectionalCascade::view_projection` was renamed to
`clip_from_world`.
- `MeshTransforms`' `transform` and `previous_transform` were renamed to
`world_from_local` and `previous_world_from_local`.
- `MeshUniform`'s `transform`, `previous_transform`,
`inverse_transpose_model_a` and `inverse_transpose_model_b` were renamed
to `world_from_local`, `previous_world_from_local`,
`local_from_world_transpose_a` and `local_from_world_transpose_b` (the
`Mesh` type in WGSL mirrors this, however `transform` and
`previous_transform` were named `model` and `previous_model`).
- `Mesh2dTransforms::transform` was renamed to `world_from_local`.
- `Mesh2dUniform`'s `transform`, `inverse_transpose_model_a` and
`inverse_transpose_model_b` were renamed to `world_from_local`,
`local_from_world_transpose_a` and `local_from_world_transpose_b` (the
`Mesh2d` type in WGSL mirrors this).
- In WGSL, in `bevy_pbr::mesh_functions`, `get_model_matrix` and
`get_previous_model_matrix` were renamed to `get_world_from_local` and
`get_previous_world_from_local`.
- In WGSL, `bevy_sprite::mesh2d_functions::get_model_matrix` was renamed
to `get_world_from_local`.
2024-06-03 16:56:53 +00:00
François Mockers
5559632977
glTF labels: add enum to avoid misspelling and keep up-to-date list documented (#13586)
# Objective

- Followup to #13548
- It added a list of all possible labels to documentation. This seems
hard to keep up and doesn't stop people from making spelling mistake

## Solution

- Add an enum that can create all the labels possible, and encourage its
use rather than manually typed labels

---------

Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com>
Co-authored-by: Rob Parrett <robparrett@gmail.com>
2024-05-31 23:25:57 +00:00
Martín Maita
f237cf2441
Updates default Text font size to 24px (#13603)
# 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.
2024-05-31 16:41:27 +00:00
Rob Parrett
06f733b16f
Use standard instruction text / position in various examples (#13583)
## 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.
2024-05-30 23:11:23 +00:00
andristarr
2b3e3341d6
separating finite and infinite 3d planes (#12426)
# Objective

Fixes #12388

## Solution

- Removing the plane3d and adding rect3d primitive mesh
2024-04-18 14:13:22 +00:00
Patrick Walton
dfdf2b9ea4
Implement the AnimationGraph, allowing for multiple animations to be blended together. (#11989)
This is an implementation of RFC #51:
https://github.com/bevyengine/rfcs/blob/main/rfcs/51-animation-composition.md

Note that the implementation strategy is different from the one outlined
in that RFC, because two-phase animation has now landed.

# Objective

Bevy needs animation blending. The RFC for this is [RFC 51].

## Solution

This is an implementation of the RFC. Note that the implementation
strategy is different from the one outlined there, because two-phase
animation has now landed.

This is just a draft to get the conversation started. Currently we're
missing a few things:

- [x] A fully-fleshed-out mechanism for transitions
- [x] A serialization format for `AnimationGraph`s
- [x] Examples are broken, other than `animated_fox`
- [x] Documentation

---

## Changelog

### Added

* The `AnimationPlayer` has been reworked to support blending multiple
animations together through an `AnimationGraph`, and as such will no
longer function unless a `Handle<AnimationGraph>` has been added to the
entity containing the player. See [RFC 51] for more details.

* Transition functionality has moved from the `AnimationPlayer` to a new
component, `AnimationTransitions`, which works in tandem with the
`AnimationGraph`.

## Migration Guide

* `AnimationPlayer`s can no longer play animations by themselves and
need to be paired with a `Handle<AnimationGraph>`. Code that was using
`AnimationPlayer` to play animations will need to create an
`AnimationGraph` asset first, add a node for the clip (or clips) you
want to play, and then supply the index of that node to the
`AnimationPlayer`'s `play` method.

* The `AnimationPlayer::play_with_transition()` method has been removed
and replaced with the `AnimationTransitions` component. If you were
previously using `AnimationPlayer::play_with_transition()`, add all
animations that you were playing to the `AnimationGraph`, and create an
`AnimationTransitions` component to manage the blending between them.

[RFC 51]:
https://github.com/bevyengine/rfcs/blob/main/rfcs/51-animation-composition.md

---------

Co-authored-by: Rob Parrett <robparrett@gmail.com>
2024-03-07 20:22:42 +00:00
Alice Cecile
599e5e4e76
Migrate from LegacyColor to bevy_color::Color (#12163)
# Objective

- As part of the migration process we need to a) see the end effect of
the migration on user ergonomics b) check for serious perf regressions
c) actually migrate the code
- To accomplish this, I'm going to attempt to migrate all of the
remaining user-facing usages of `LegacyColor` in one PR, being careful
to keep a clean commit history.
- Fixes #12056.

## Solution

I've chosen to use the polymorphic `Color` type as our standard
user-facing API.

- [x] Migrate `bevy_gizmos`.
- [x] Take `impl Into<Color>` in all `bevy_gizmos` APIs
- [x] Migrate sprites
- [x] Migrate UI
- [x] Migrate `ColorMaterial`
- [x] Migrate `MaterialMesh2D`
- [x] Migrate fog
- [x] Migrate lights
- [x] Migrate StandardMaterial
- [x] Migrate wireframes
- [x] Migrate clear color
- [x] Migrate text
- [x] Migrate gltf loader
- [x] Register color types for reflection
- [x] Remove `LegacyColor`
- [x] Make sure CI passes

Incidental improvements to ease migration:

- added `Color::srgba_u8`, `Color::srgba_from_array` and friends
- added `set_alpha`, `is_fully_transparent` and `is_fully_opaque` to the
`Alpha` trait
- add and immediately deprecate (lol) `Color::rgb` and friends in favor
of more explicit and consistent `Color::srgb`
- standardized on white and black for most example text colors
- added vector field traits to `LinearRgba`: ~~`Add`, `Sub`,
`AddAssign`, `SubAssign`,~~ `Mul<f32>` and `Div<f32>`. Multiplications
and divisions do not scale alpha. `Add` and `Sub` have been cut from
this PR.
- added `LinearRgba` and `Srgba` `RED/GREEN/BLUE`
- added `LinearRgba_to_f32_array` and `LinearRgba::to_u32`

## Migration Guide

Bevy's color types have changed! Wherever you used a
`bevy::render::Color`, a `bevy::color::Color` is used instead.

These are quite similar! Both are enums storing a color in a specific
color space (or to be more precise, using a specific color model).
However, each of the different color models now has its own type.

TODO...

- `Color::rgba`, `Color::rgb`, `Color::rbga_u8`, `Color::rgb_u8`,
`Color::rgb_from_array` are now `Color::srgba`, `Color::srgb`,
`Color::srgba_u8`, `Color::srgb_u8` and `Color::srgb_from_array`.
- `Color::set_a` and `Color::a` is now `Color::set_alpha` and
`Color::alpha`. These are part of the `Alpha` trait in `bevy_color`.
- `Color::is_fully_transparent` is now part of the `Alpha` trait in
`bevy_color`
- `Color::r`, `Color::set_r`, `Color::with_r` and the equivalents for
`g`, `b` `h`, `s` and `l` have been removed due to causing silent
relatively expensive conversions. Convert your `Color` into the desired
color space, perform your operations there, and then convert it back
into a polymorphic `Color` enum.
- `Color::hex` is now `Srgba::hex`. Call `.into` or construct a
`Color::Srgba` variant manually to convert it.
- `WireframeMaterial`, `ExtractedUiNode`, `ExtractedDirectionalLight`,
`ExtractedPointLight`, `ExtractedSpotLight` and `ExtractedSprite` now
store a `LinearRgba`, rather than a polymorphic `Color`
- `Color::rgb_linear` and `Color::rgba_linear` are now
`Color::linear_rgb` and `Color::linear_rgba`
- The various CSS color constants are no longer stored directly on
`Color`. Instead, they're defined in the `Srgba` color space, and
accessed via `bevy::color::palettes::css`. Call `.into()` on them to
convert them into a `Color` for quick debugging use, and consider using
the much prettier `tailwind` palette for prototyping.
- The `LIME_GREEN` color has been renamed to `LIMEGREEN` to comply with
the standard naming.
- Vector field arithmetic operations on `Color` (add, subtract, multiply
and divide by a f32) have been removed. Instead, convert your colors
into `LinearRgba` space, and perform your operations explicitly there.
This is particularly relevant when working with emissive or HDR colors,
whose color channel values are routinely outside of the ordinary 0 to 1
range.
- `Color::as_linear_rgba_f32` has been removed. Call
`LinearRgba::to_f32_array` instead, converting if needed.
- `Color::as_linear_rgba_u32` has been removed. Call
`LinearRgba::to_u32` instead, converting if needed.
- Several other color conversion methods to transform LCH or HSL colors
into float arrays or `Vec` types have been removed. Please reimplement
these externally or open a PR to re-add them if you found them
particularly useful.
- Various methods on `Color` such as `rgb` or `hsl` to convert the color
into a specific color space have been removed. Convert into
`LinearRgba`, then to the color space of your choice.
- Various implicitly-converting color value methods on `Color` such as
`r`, `g`, `b` or `h` have been removed. Please convert it into the color
space of your choice, then check these properties.
- `Color` no longer implements `AsBindGroup`. Store a `LinearRgba`
internally instead to avoid conversion costs.

---------

Co-authored-by: Alice Cecile <alice.i.cecil@gmail.com>
Co-authored-by: Afonso Lage <lage.afonso@gmail.com>
Co-authored-by: Rob Parrett <robparrett@gmail.com>
Co-authored-by: Zachary Harrold <zac@harrold.com.au>
2024-02-29 19:35:12 +00:00
Nicola Papale
f7f7e326e5
Add methods to directly load assets from World (#12023)
# Objective

`FromWorld` is often used to group loading and creation of assets for
resources.

With this setup, users often end up repetitively calling
`.resource::<AssetServer>` and `.resource_mut::<Assets<T>>`, and may
have difficulties handling lifetimes of the returned references.

## Solution

Add extension methods to `World` to add and load assets, through a new
extension trait defined in `bevy_asset`.

### Other considerations

* This might be a bit too "magic", as it makes implicit the resource
access.
* We could also implement `DirectAssetAccessExt` on `App`, but it didn't
feel necessary, as `FromWorld` is the principal use-case here.

---

## Changelog

* Add the `DirectAssetAccessExt` trait, which adds the `add_asset`,
`load_asset` and `load_asset_with_settings` method to the `World` type.
2024-02-27 00:28:26 +00:00
Alice Cecile
de004da8d5
Rename bevy_render::Color to LegacyColor (#12069)
# Objective

The migration process for `bevy_color` (#12013) will be fairly involved:
there will be hundreds of affected files, and a large number of APIs.

## Solution

To allow us to proceed granularly, we're going to keep both
`bevy_color::Color` (new) and `bevy_render::Color` (old) around until
the migration is complete.

However, simply doing this directly is confusing! They're both called
`Color`, making it very hard to tell when a portion of the code has been
ported.

As discussed in #12056, by renaming the old `Color` type, we can make it
easier to gradually migrate over, one API at a time.

## Migration Guide

THIS MIGRATION GUIDE INTENTIONALLY LEFT BLANK.

This change should not be shipped to end users: delete this section in
the final migration guide!

---------

Co-authored-by: Alice Cecile <alice.i.cecil@gmail.com>
2024-02-24 21:35:32 +00:00
Carter Anderson
8127d44daa
Irradiance volume example tweaks (#11911)
# Objective

Fixes two small quality issues:

1. With the new default ev100 exposure value, the irradiance intensity
was too low
2. The camera was rotating at a fixed speed (instead of a speed
multiplied by delta time), resulting in frame-rate dependent rotation
speed.
2024-02-17 01:24:50 +00:00
Joona Aalto
0166db33f7
Deprecate shapes in bevy_render::mesh::shape (#11773)
# Objective

#11431 and #11688 implemented meshing support for Bevy's new geometric
primitives. The next step is to deprecate the shapes in
`bevy_render::mesh::shape` and to later remove them completely for 0.14.

## Solution

Deprecate the shapes and reduce code duplication by utilizing the
primitive meshing API for the old shapes where possible.

Note that some shapes have behavior that can't be exactly reproduced
with the new primitives yet:

- `Box` is more of an AABB with min/max extents
- `Plane` supports a subdivision count
- `Quad` has a `flipped` property

These types have not been changed to utilize the new primitives yet.

---

## Changelog

- Deprecated all shapes in `bevy_render::mesh::shape`
- Changed all examples to use new primitives for meshing

## Migration Guide

Bevy has previously used rendering-specific types like `UVSphere` and
`Quad` for primitive mesh shapes. These have now been deprecated to use
the geometric primitives newly introduced in version 0.13.

Some examples:

```rust
let before = meshes.add(shape::Box::new(5.0, 0.15, 5.0));
let after = meshes.add(Cuboid::new(5.0, 0.15, 5.0));

let before = meshes.add(shape::Quad::default());
let after = meshes.add(Rectangle::default());

let before = meshes.add(shape::Plane::from_size(5.0));
// The surface normal can now also be specified when using `new`
let after = meshes.add(Plane3d::default().mesh().size(5.0, 5.0));

let before = meshes.add(
    Mesh::try_from(shape::Icosphere {
        radius: 0.5,
        subdivisions: 5,
    })
    .unwrap(),
);
let after = meshes.add(Sphere::new(0.5).mesh().ico(5).unwrap());
```
2024-02-08 18:01:34 +00:00
Patrick Walton
4c15dd0fc5
Implement irradiance volumes. (#10268)
# Objective

Bevy could benefit from *irradiance volumes*, also known as *voxel
global illumination* or simply as light probes (though this term is not
preferred, as multiple techniques can be called light probes).
Irradiance volumes are a form of baked global illumination; they work by
sampling the light at the centers of each voxel within a cuboid. At
runtime, the voxels surrounding the fragment center are sampled and
interpolated to produce indirect diffuse illumination.

## Solution

This is divided into two sections. The first is copied and pasted from
the irradiance volume module documentation and describes the technique.
The second part consists of notes on the implementation.

### Overview

An *irradiance volume* is a cuboid voxel region consisting of
regularly-spaced precomputed samples of diffuse indirect light. They're
ideal if you have a dynamic object such as a character that can move
about
static non-moving geometry such as a level in a game, and you want that
dynamic object to be affected by the light bouncing off that static
geometry.

To use irradiance volumes, you need to precompute, or *bake*, the
indirect
light in your scene. Bevy doesn't currently come with a way to do this.
Fortunately, [Blender] provides a [baking tool] as part of the Eevee
renderer, and its irradiance volumes are compatible with those used by
Bevy.
The [`bevy-baked-gi`] project provides a tool, `export-blender-gi`, that
can
extract the baked irradiance volumes from the Blender `.blend` file and
package them up into a `.ktx2` texture for use by the engine. See the
documentation in the `bevy-baked-gi` project for more details as to this
workflow.

Like all light probes in Bevy, irradiance volumes are 1×1×1 cubes that
can
be arbitrarily scaled, rotated, and positioned in a scene with the
[`bevy_transform::components::Transform`] component. The 3D voxel grid
will
be stretched to fill the interior of the cube, and the illumination from
the
irradiance volume will apply to all fragments within that bounding
region.

Bevy's irradiance volumes are based on Valve's [*ambient cubes*] as used
in
*Half-Life 2* ([Mitchell 2006], slide 27). These encode a single color
of
light from the six 3D cardinal directions and blend the sides together
according to the surface normal.

The primary reason for choosing ambient cubes is to match Blender, so
that
its Eevee renderer can be used for baking. However, they also have some
advantages over the common second-order spherical harmonics approach:
ambient cubes don't suffer from ringing artifacts, they are smaller (6
colors for ambient cubes as opposed to 9 for spherical harmonics), and
evaluation is faster. A smaller basis allows for a denser grid of voxels
with the same storage requirements.

If you wish to use a tool other than `export-blender-gi` to produce the
irradiance volumes, you'll need to pack the irradiance volumes in the
following format. The irradiance volume of resolution *(Rx, Ry, Rz)* is
expected to be a 3D texture of dimensions *(Rx, 2Ry, 3Rz)*. The
unnormalized
texture coordinate *(s, t, p)* of the voxel at coordinate *(x, y, z)*
with
side *S* ∈ *{-X, +X, -Y, +Y, -Z, +Z}* is as follows:

```text
s = x

t = y + ⎰  0 if S ∈ {-X, -Y, -Z}
        ⎱ Ry if S ∈ {+X, +Y, +Z}

        ⎧   0 if S ∈ {-X, +X}
p = z + ⎨  Rz if S ∈ {-Y, +Y}
        ⎩ 2Rz if S ∈ {-Z, +Z}
```

Visually, in a left-handed coordinate system with Y up, viewed from the
right, the 3D texture looks like a stacked series of voxel grids, one
for
each cube side, in this order:

| **+X** | **+Y** | **+Z** |
| ------ | ------ | ------ |
| **-X** | **-Y** | **-Z** |

A terminology note: Other engines may refer to irradiance volumes as
*voxel
global illumination*, *VXGI*, or simply as *light probes*. Sometimes
*light
probe* refers to what Bevy calls a reflection probe. In Bevy, *light
probe*
is a generic term that encompasses all cuboid bounding regions that
capture
indirect illumination, whether based on voxels or not.

Note that, if binding arrays aren't supported (e.g. on WebGPU or WebGL
2),
then only the closest irradiance volume to the view will be taken into
account during rendering.

[*ambient cubes*]:
https://advances.realtimerendering.com/s2006/Mitchell-ShadingInValvesSourceEngine.pdf

[Mitchell 2006]:
https://advances.realtimerendering.com/s2006/Mitchell-ShadingInValvesSourceEngine.pdf

[Blender]: http://blender.org/

[baking tool]:
https://docs.blender.org/manual/en/latest/render/eevee/render_settings/indirect_lighting.html

[`bevy-baked-gi`]: https://github.com/pcwalton/bevy-baked-gi

### Implementation notes

This patch generalizes light probes so as to reuse as much code as
possible between irradiance volumes and the existing reflection probes.
This approach was chosen because both techniques share numerous
similarities:

1. Both irradiance volumes and reflection probes are cuboid bounding
regions.
2. Both are responsible for providing baked indirect light.
3. Both techniques involve presenting a variable number of textures to
the shader from which indirect light is sampled. (In the current
implementation, this uses binding arrays.)
4. Both irradiance volumes and reflection probes require gathering and
sorting probes by distance on CPU.
5. Both techniques require the GPU to search through a list of bounding
regions.
6. Both will eventually want to have falloff so that we can smoothly
blend as objects enter and exit the probes' influence ranges. (This is
not implemented yet to keep this patch relatively small and reviewable.)

To do this, we generalize most of the methods in the reflection probes
patch #11366 to be generic over a trait, `LightProbeComponent`. This
trait is implemented by both `EnvironmentMapLight` (for reflection
probes) and `IrradianceVolume` (for irradiance volumes). Using a trait
will allow us to add more types of light probes in the future. In
particular, I highly suspect we will want real-time reflection planes
for mirrors in the future, which can be easily slotted into this
framework.

## Changelog

> This section is optional. If this was a trivial fix, or has no
externally-visible impact, you can delete this section.

### Added
* A new `IrradianceVolume` asset type is available for baked voxelized
light probes. You can bake the global illumination using Blender or
another tool of your choice and use it in Bevy to apply indirect
illumination to dynamic objects.
2024-02-06 23:23:20 +00:00