Fix oit webgl (#15728)

The previous fixes were breaking pretty much everything on main due to
naga-oil complaining about the OIT shader not being loaded, since
apparently webgl is a default feature. This fix is a bit messier, but
properly warns the user and is probably what we should have gone for in
the first place.

crates/bevy_core_pipeline/src/lib.rs

@@ -76,7 +76,6 @@ use crate::{
 use bevy_app::{App, Plugin};
 use bevy_asset::load_internal_asset;
 use bevy_render::prelude::Shader;
-#[cfg(not(feature = "webgl"))]
 use oit::OrderIndependentTransparencyPlugin;
 
 #[derive(Default)]
@@ -110,8 +109,6 @@ impl Plugin for CorePipelinePlugin {
  DepthOfFieldPlugin,
  SmaaPlugin,
  PostProcessingPlugin,
- // DownlevelFlags::FRAGMENT_WRITABLE_STORAGE is required for OIT
- #[cfg(not(feature = "webgl"))]
  OrderIndependentTransparencyPlugin,
  ));
  }

crates/bevy_core_pipeline/src/oit/resolve/mod.rs

@@ -1,3 +1,7 @@
+use crate::{
+ fullscreen_vertex_shader::fullscreen_shader_vertex_state,
+ oit::OrderIndependentTransparencySettings,
+};
 use bevy_app::Plugin;
 use bevy_asset::{load_internal_asset, Handle};
 use bevy_derive::Deref;
@@ -9,20 +13,16 @@ use bevy_render::{
  render_resource::{
  binding_types::{storage_buffer_sized, texture_depth_2d, uniform_buffer},
  BindGroup, BindGroupEntries, BindGroupLayout, BindGroupLayoutEntries, BlendComponent,
- BlendState, CachedRenderPipelineId, ColorTargetState, ColorWrites, FragmentState,
- MultisampleState, PipelineCache, PrimitiveState, RenderPipelineDescriptor, Shader,
- ShaderStages, TextureFormat,
+ BlendState, CachedRenderPipelineId, ColorTargetState, ColorWrites, DownlevelFlags,
+ FragmentState, MultisampleState, PipelineCache, PrimitiveState, RenderPipelineDescriptor,
+ Shader, ShaderStages, TextureFormat,
  },
- renderer::RenderDevice,
+ renderer::{RenderAdapter, RenderDevice},
  texture::BevyDefault,
  view::{ExtractedView, ViewTarget, ViewUniform, ViewUniforms},
  Render, RenderApp, RenderSet,
 };
-
-use crate::{
- fullscreen_vertex_shader::fullscreen_shader_vertex_state,
- oit::OrderIndependentTransparencySettings,
-};
+use bevy_utils::tracing::warn;
 
 use super::OitBuffers;
 
@@ -42,26 +42,33 @@ impl Plugin for OitResolvePlugin {
  "oit_resolve.wgsl",
  Shader::from_wgsl
  );
-
- let Some(render_app) = app.get_sub_app_mut(RenderApp) else {
- return;
- };
-
- render_app.add_systems(
- Render,
- (
- queue_oit_resolve_pipeline.in_set(RenderSet::Queue),
- prepare_oit_resolve_bind_group.in_set(RenderSet::PrepareBindGroups),
- ),
- );
  }
 
  fn finish(&self, app: &mut bevy_app::App) {
  let Some(render_app) = app.get_sub_app_mut(RenderApp) else {
  return;
  };
 
- render_app.init_resource::<OitResolvePipeline>();
+ if !render_app
+ .world()
+ .resource::<RenderAdapter>()
+ .get_downlevel_capabilities()
+ .flags
+ .contains(DownlevelFlags::FRAGMENT_WRITABLE_STORAGE)
+ {
+ warn!("OrderIndependentTransparencyPlugin not loaded. GPU lacks support: DownlevelFlags::FRAGMENT_WRITABLE_STORAGE.");
+ return;
+ }
+
+ render_app
+ .add_systems(
+ Render,
+ (
+ queue_oit_resolve_pipeline.in_set(RenderSet::Queue),
+ prepare_oit_resolve_bind_group.in_set(RenderSet::PrepareBindGroups),
+ ),
+ )
+ .init_resource::<OitResolvePipeline>();
  }
 }
 

crates/bevy_pbr/src/render/mesh_view_bindings.rs

@@ -1,6 +1,4 @@
 use alloc::sync::Arc;
-use core::{array, num::NonZero};
-
 use bevy_core_pipeline::{
  core_3d::ViewTransmissionTexture,
  oit::{OitBuffers, OrderIndependentTransparencySettings},
@@ -29,9 +27,11 @@ use bevy_render::{
  VISIBILITY_RANGES_STORAGE_BUFFER_COUNT,
  },
 };
+use core::{array, num::NonZero};
 
 #[cfg(all(feature = "webgl", target_arch = "wasm32", not(feature = "webgpu")))]
 use bevy_render::render_resource::binding_types::texture_cube;
+use bevy_render::renderer::RenderAdapter;
 #[cfg(debug_assertions)]
 use bevy_utils::warn_once;
 use environment_map::EnvironmentMapLight;
@@ -194,6 +194,7 @@ fn layout_entries(
  visibility_ranges_buffer_binding_type: BufferBindingType,
  layout_key: MeshPipelineViewLayoutKey,
  render_device: &RenderDevice,
+ render_adapter: &RenderAdapter,
 ) -> Vec<BindGroupLayoutEntry> {
  let mut entries = DynamicBindGroupLayoutEntries::new_with_indices(
  ShaderStages::FRAGMENT,
@@ -358,15 +359,25 @@ fn layout_entries(
  ));
 
  // OIT
- if cfg!(not(feature = "webgl")) && layout_key.contains(MeshPipelineViewLayoutKey::OIT_ENABLED) {
- entries = entries.extend_with_indices((
- // oit_layers
- (31, storage_buffer_sized(false, None)),
- // oit_layer_ids,
- (32, storage_buffer_sized(false, None)),
- // oit_layer_count
- (33, uniform_buffer::<i32>(true)),
- ));
+ if layout_key.contains(MeshPipelineViewLayoutKey::OIT_ENABLED) {
+ // Check if the GPU supports writable storage buffers in the fragment shader
+ // If not, we can't use OIT, so we skip the OIT bindings.
+ // This is a hack to avoid errors on webgl -- the OIT plugin will warn the user that OIT
+ // is not supported on their platform, so we don't need to do it here.
+ if render_adapter
+ .get_downlevel_capabilities()
+ .flags
+ .contains(DownlevelFlags::FRAGMENT_WRITABLE_STORAGE)
+ {
+ entries = entries.extend_with_indices((
+ // oit_layers
+ (31, storage_buffer_sized(false, None)),
+ // oit_layer_ids,
+ (32, storage_buffer_sized(false, None)),
+ // oit_layer_count
+ (33, uniform_buffer::<i32>(true)),
+ ));
+ }
  }
 
  entries.to_vec()
@@ -387,6 +398,7 @@ impl FromWorld for MeshPipelineViewLayouts {
  // [`MeshPipelineViewLayoutKey`] flags.
 
  let render_device = world.resource::<RenderDevice>();
+ let render_adapter = world.resource::<RenderAdapter>();
 
  let clustered_forward_buffer_binding_type = render_device
  .get_supported_read_only_binding_type(CLUSTERED_FORWARD_STORAGE_BUFFER_COUNT);
@@ -400,6 +412,7 @@ impl FromWorld for MeshPipelineViewLayouts {
  visibility_ranges_buffer_binding_type,
  key,
  render_device,
+ render_adapter,
  );
  #[cfg(debug_assertions)]
  let texture_count: usize = entries
@@ -436,6 +449,7 @@ impl MeshPipelineViewLayouts {
 /// [`MeshPipelineViewLayoutKey`] flags.
 pub fn generate_view_layouts(
  render_device: &RenderDevice,
+ render_adapter: &RenderAdapter,
  clustered_forward_buffer_binding_type: BufferBindingType,
  visibility_ranges_buffer_binding_type: BufferBindingType,
 ) -> [MeshPipelineViewLayout; MeshPipelineViewLayoutKey::COUNT] {
@@ -446,6 +460,7 @@ pub fn generate_view_layouts(
  visibility_ranges_buffer_binding_type,
  key,
  render_device,
+ render_adapter,
  );
 
  #[cfg(debug_assertions)]

crates/bevy_render/src/render_resource/mod.rs

@@ -42,8 +42,8 @@ pub use wgpu::{
  BufferBinding, BufferBindingType, BufferDescriptor, BufferSize, BufferUsages, ColorTargetState,
  ColorWrites, CommandEncoder, CommandEncoderDescriptor, CompareFunction, ComputePass,
  ComputePassDescriptor, ComputePipelineDescriptor as RawComputePipelineDescriptor,
- DepthBiasState, DepthStencilState, Extent3d, Face, Features as WgpuFeatures, FilterMode,
- FragmentState as RawFragmentState, FrontFace, ImageCopyBuffer, ImageCopyBufferBase,
+ DepthBiasState, DepthStencilState, DownlevelFlags, Extent3d, Face, Features as WgpuFeatures,
+ FilterMode, FragmentState as RawFragmentState, FrontFace, ImageCopyBuffer, ImageCopyBufferBase,
  ImageCopyTexture, ImageCopyTextureBase, ImageDataLayout, ImageSubresourceRange, IndexFormat,
  Limits as WgpuLimits, LoadOp, Maintain, MapMode, MultisampleState, Operations, Origin3d,
  PipelineCompilationOptions, PipelineLayout, PipelineLayoutDescriptor, PolygonMode,