bevy/release-content
JMS55 bab31e3777
Initial raytraced lighting progress (bevy_solari) (#19058)
# Bevy Solari 
<img
src="https://github.com/user-attachments/assets/94061fc8-01cf-4208-b72a-8eecad610d76"
width="100" />

## Preface
- See release notes.
- Please talk to me in #rendering-dev on discord or open a github
discussion if you have questions about the long term plan, and keep
discussion in this PR limited to the contents of the PR :)

## Connections
- Works towards #639, #16408.
- Spawned https://github.com/bevyengine/bevy/issues/18993.
- Need to fix RT stuff in naga_oil first
https://github.com/bevyengine/naga_oil/pull/116.

## This PR

After nearly two years, I've revived the raytraced lighting effort I
first started in https://github.com/bevyengine/bevy/pull/10000.

Unlike that PR, which has realtime techniques, I've limited this PR to:
* `RaytracingScenePlugin` - BLAS and TLAS building, geometry and texture
binding, sampling functions.
* `PathtracingPlugin` - A non-realtime path tracer intended to serve as
a testbed and reference.

## What's implemented?

![image](https://github.com/user-attachments/assets/06522007-c205-46eb-8178-823f19917def)

* BLAS building on mesh load
* Emissive lights
* Directional lights with soft shadows
* Diffuse (lambert, not Bevy's diffuse BRDF) and emissive materials
* A reference path tracer with:
  * Antialiasing
  * Direct light sampling (next event estimation) with 0/1 MIS weights
  * Importance-sampled BRDF bounces
  * Russian roulette 

## What's _not_ implemented?
* Anything realtime, including a real-time denoiser
* Integration with Bevy's rasterized gbuffer
* Specular materials
* Non-opaque geometry
* Any sort of CPU or GPU optimizations
* BLAS compaction, proper bindless, and further RT APIs are things that
we need wgpu to add
* PointLights, SpotLights, or skyboxes / environment lighting 
* Support for materials other than StandardMaterial (and only a subset
of properties are supported)
* Skinned/morphed or otherwise animating/deformed meshes
* Mipmaps
* Adaptive self-intersection ray bias
* A good way for developers to detect whether the user's GPU supports RT
or not, and fallback to baked lighting.
* Documentation and actual finalized APIs (literally everything is
subject to change)

## End-user Usage
* Have a GPU that supports RT with inline ray queries
* Add `SolariPlugin` to your app
* Ensure any `Mesh` asset you want to use for raytracing has
`enable_raytracing: true` (defaults to true), and that it uses the
standard uncompressed position/normal/uv_0/tangent vertex attribute set,
triangle list topology, and 32-bit indices.
* If you don't want to build a BLAS and use the mesh for RT, set
enable_raytracing to false.
* Add the `RaytracingMesh3d` component to your entity (separate from
`Mesh3d` or `MeshletMesh3d`).

## Testing

- Did you test these changes? If so, how? 
  - Ran the solari example.
- Are there any parts that need more testing?
  - Other test scenes probably. Normal mapping would be good to test.
- How can other people (reviewers) test your changes? Is there anything
specific they need to know?
  - See the solari.rs example for how to setup raytracing.
- If relevant, what platforms did you test these changes on, and are
there any important ones you can't test?
  - Windows 11, NVIDIA RTX 3080.

---------

Co-authored-by: atlv <email@atlasdostal.com>
Co-authored-by: IceSentry <IceSentry@users.noreply.github.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
2025-06-12 21:26:10 +00:00
..
migration-guides Make GILRS and WINIT_WINDOWS public (#19575) 2025-06-12 20:05:00 +00:00
release-notes Initial raytraced lighting progress (bevy_solari) (#19058) 2025-06-12 21:26:10 +00:00
migration_guides_template.md Make some changes to the migration guide recommendations (#18794) 2025-04-10 19:25:56 +00:00
migration_guides.md bevyengine.org -> bevy.org (#19503) 2025-06-05 23:09:28 +00:00
README.md Fixed broken link in release content README. (#19375) 2025-05-26 19:30:03 +00:00
release_notes_template.md
release_notes.md bevyengine.org -> bevy.org (#19503) 2025-06-05 23:09:28 +00:00

Release Content

This directory contains drafts of documentation for the current development cycle, which will be published to the website during the next release. You can find more information in the release notes and migration guides files.