Visse 6f270d4776 Expose pipeline constants to materials (#24502) ...

# Objective

Allow materials to use pipeline constants ([pipeline-overridable
constants](https://www.w3.org/TR/WGSL/#override-decls)).
They are already available in wgpu, but bevy didn't expose them.

## Solution

Expose constants in `RenderPipelineDescriptor` &
`ComputePipelineDescriptor`, allowing materials to specify them in their
specilize function.

**Note:** I had to remove the `Eq` derive from
`ComputePipelineDescriptor`, `VertexState` and `FragmentState`, due to
the new f64 field. It was already a bit inconsistent with
`RenderPipelineDescriptor` not having it.

## Testing
- Ran `cargo check`
- Created an example & ran it
- Couldn't run `cargo test` due to it taking looots of disk space to
run, but I have a hard time seeing it break something at runtime

## Showcase

See the added example, where pipeline constants are used to change the
`LEVELS` override in WGSL.
<img width="760" height="289" alt="Screenshot from 2026-05-31 09-46-05"
src="https://github.com/user-attachments/assets/6902757c-aea4-4b91-9ff0-e653ce4c3448"
/>

2026-06-09 00:06:01 +00:00

..

animate_shader.rs

Use bevy::shader in examples instead of bevy::render::shader re-export (#20492)

2025-08-10 18:08:47 +00:00

array_texture.rs

Replace all different load variants in AssetServer with a builder. (#23663)

2026-04-15 18:32:25 +00:00

automatic_instancing.rs

Use bevy::shader in examples instead of bevy::render::shader re-export (#20492)

2025-08-10 18:08:47 +00:00

compute_shader_game_of_life.rs

Replace RenderGraph with systems (#22144)

2026-01-28 21:09:59 +00:00

extended_material_bindless.rs

Fix copy-pasting mistake in extended material bindless example (#22373)

2026-01-05 02:06:01 +00:00

extended_material.rs

bevy_material (#22426)

2026-01-13 21:41:06 +00:00

fallback_image.rs

Use bevy::shader in examples instead of bevy::render::shader re-export (#20492)

2025-08-10 18:08:47 +00:00

gpu_readback.rs

Add ReadbackOnce component to help one-shot readbacks. (#23845)

2026-05-22 13:41:31 +00:00

pipeline_constants.rs

Expose pipeline constants to materials (#24502)

2026-06-09 00:06:01 +00:00

shader_defs.rs

Use boxed storage for material erasure. (#20614)

2025-08-17 16:37:33 +00:00

shader_material_2d.rs

Split out sprite rendering (#20587)

2025-08-15 22:41:05 +00:00

shader_material_bindless.rs

Use bevy::shader in examples instead of bevy::render::shader re-export (#20492)

2025-08-10 18:08:47 +00:00

shader_material_glsl.rs

Use bevy::shader in examples instead of bevy::render::shader re-export (#20492)

2025-08-10 18:08:47 +00:00

shader_material_screenspace_texture.rs

Use bevy::shader in examples instead of bevy::render::shader re-export (#20492)

2025-08-10 18:08:47 +00:00

shader_material_wesl.rs

Change ShaderDefVal to use Cow<'static, str> (#24209)

2026-05-21 14:34:41 +00:00

shader_material.rs

Use bevy::shader in examples instead of bevy::render::shader re-export (#20492)

2025-08-10 18:08:47 +00:00

shader_prepass.rs

Add tools to avoid unnecessary AssetEvent::Modified events that lead to rendering performance costs (#16751) (#22460)

2026-02-10 18:39:37 +00:00

storage_buffer.rs

Add tools to avoid unnecessary AssetEvent::Modified events that lead to rendering performance costs (#16751) (#22460)

2026-02-10 18:39:37 +00:00