Marco Buono 5733d2403e *_PREPASS Shader Def Cleanup (#10136) ... # Objective - This PR aims to make the various `*_PREPASS` shader defs we have (`NORMAL_PREPASS`, `DEPTH_PREPASS`, `MOTION_VECTORS_PREPASS` AND `DEFERRED_PREPASS`) easier to use and understand: - So that their meaning is now consistent across all contexts; (“prepass X is enabled for the current view”) - So that they're also consistently set across all contexts. - It also aims to enable us to (with a follow up PR) to conditionally gate the `BindGroupEntry` and `BindGroupLayoutEntry` items associated with these prepasses, saving us up to 4 texture slots in WebGL (currently globally limited to 16 per shader, regardless of bind groups) ## Solution - We now consistently set these from `PrepassPipeline`, the `MeshPipeline` and the `DeferredLightingPipeline`, we also set their `MeshPipelineKey`s; - We introduce `PREPASS_PIPELINE`, `MESH_PIPELINE` and `DEFERRED_LIGHTING_PIPELINE` that can be used to detect where the code is running, without overloading the meanings of the prepass shader defs; - We also gate the WGSL functions in `bevy_pbr::prepass_utils` with `#ifdef`s for their respective shader defs, so that shader code can provide a fallback whenever they're not available. - This allows us to conditionally include the bindings for these prepass textures (My next PR, which will hopefully unblock #8015) - @robtfm mentioned [these were being used to prevent accessing the same binding as read/write in the prepass](https://discord.com/channels/691052431525675048/743663924229963868/1163270458393759814), however even after reversing the `#ifndef`s I had no issues running the code, so perhaps the compiler is already smart enough even without tree shaking to know they're not being used, thanks to `#ifdef PREPASS_PIPELINE`? ## Comparison ### Before | Shader Def | `PrepassPipeline` | `MeshPipeline` | `DeferredLightingPipeline` | | ------------------------ | ----------------- | -------------- | -------------------------- | | `NORMAL_PREPASS` | Yes | No | No | | `DEPTH_PREPASS` | Yes | No | No | | `MOTION_VECTORS_PREPASS` | Yes | No | No | | `DEFERRED_PREPASS` | Yes | No | No | | View Key | `PrepassPipeline` | `MeshPipeline` | `DeferredLightingPipeline` | | ------------------------ | ----------------- | -------------- | -------------------------- | | `NORMAL_PREPASS` | Yes | Yes | No | | `DEPTH_PREPASS` | Yes | No | No | | `MOTION_VECTORS_PREPASS` | Yes | No | No | | `DEFERRED_PREPASS` | Yes | Yes\* | No | \* Accidentally was being set twice, once with only `deferred_prepass.is_some()` as a condition, and once with `deferred_p repass.is_some() && !forward` as a condition. ### After | Shader Def | `PrepassPipeline` | `MeshPipeline` | `DeferredLightingPipeline` | | ---------------------------- | ----------------- | --------------- | -------------------------- | | `NORMAL_PREPASS` | Yes | Yes | Yes | | `DEPTH_PREPASS` | Yes | Yes | Yes | | `MOTION_VECTORS_PREPASS` | Yes | Yes | Yes | | `DEFERRED_PREPASS` | Yes | Yes | Unconditionally | | `PREPASS_PIPELINE` | Unconditionally | No | No | | `MESH_PIPELINE` | No | Unconditionally | No | | `DEFERRED_LIGHTING_PIPELINE` | No | No | Unconditionally | | View Key | `PrepassPipeline` | `MeshPipeline` | `DeferredLightingPipeline` | | ------------------------ | ----------------- | -------------- | -------------------------- | | `NORMAL_PREPASS` | Yes | Yes | Yes | | `DEPTH_PREPASS` | Yes | Yes | Yes | | `MOTION_VECTORS_PREPASS` | Yes | Yes | Yes | | `DEFERRED_PREPASS` | Yes | Yes | Unconditionally | --- ## Changelog - Cleaned up WGSL `*_PREPASS` shader defs so they're now consistently used everywhere; - Introduced `PREPASS_PIPELINE`, `MESH_PIPELINE` and `DEFERRED_LIGHTING_PIPELINE` WGSL shader defs for conditionally compiling logic based the current pipeline; - WGSL functions from `bevy_pbr::prepass_utils` are now guarded with `#ifdef` based on the currently enabled prepasses; ## Migration Guide - When using functions from `bevy_pbr::prepass_utils` (`prepass_depth()`, `prepass_normal()`, `prepass_motion_vector()`) in contexts where these prepasses might be disabled, you should now wrap your calls with the appropriate `#ifdef` guards, (`#ifdef DEPTH_PREPASS`, `#ifdef NORMAL_PREPASS`, `#ifdef MOTION_VECTOR_PREPASS`) providing fallback logic where applicable. --------- Co-authored-by: Carter Anderson <mcanders1@gmail.com> Co-authored-by: IceSentry <IceSentry@users.noreply.github.com>		2023-10-17 00:16:21 +00:00
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src	*_PREPASS Shader Def Cleanup (#10136)	2023-10-17 00:16:21 +00:00
Cargo.toml	wgpu 0.17 (#9302)	2023-10-09 20:15:24 +00:00