Implement per-pixel linked list for OIT

crates/bevy_core_pipeline/src/core_3d/main_transparent_pass_3d_node.rs

@@ -1,11 +1,14 @@
-use crate::core_3d::Transparent3d;
+use crate::{
+    core_3d::Transparent3d,
+    oit::{resolve::OitResolvePipelineId, OrderIndependentTransparencySettings},
+};
 use bevy_camera::{MainPassResolutionOverride, Viewport};
 use bevy_ecs::prelude::*;
 use bevy_render::{
     camera::ExtractedCamera,
     diagnostic::RecordDiagnostics,
     render_phase::ViewSortedRenderPhases,
-    render_resource::{RenderPassDescriptor, StoreOp},
+    render_resource::{PipelineCache, RenderPassDescriptor, StoreOp},
     renderer::{RenderContext, ViewQuery},
     view::{ExtractedView, ViewDepthTexture, ViewTarget},
 };
@@ -21,13 +24,23 @@ pub fn main_transparent_pass_3d(
         &ViewTarget,
         &ViewDepthTexture,
         Option<&MainPassResolutionOverride>,
+        Has<OrderIndependentTransparencySettings>,
+        Option<&OitResolvePipelineId>,
     )>,
     transparent_phases: Res<ViewSortedRenderPhases<Transparent3d>>,
     mut ctx: RenderContext,
 ) {
     let view_entity = view.entity();
 
-    let (camera, extracted_view, target, depth, resolution_override) = view.into_inner();
+    let (
+        camera,
+        extracted_view,
+        target,
+        depth,
+        resolution_override,
+        has_oit,
+        oit_resolve_pipeline_id,
+    ) = view.into_inner();
 
     let Some(transparent_phase) = transparent_phases.get(&extracted_view.retained_view_entity)
     else {
@@ -41,6 +54,22 @@ pub fn main_transparent_pass_3d(
         let diagnostics = ctx.diagnostic_recorder();
         let diagnostics = diagnostics.as_deref();
 
+        if has_oit {
+            // We can't run transparent phase if OitResolvePipelineId is not ready
+            // Otherwise we will write to `oit_atomic_counter` and `oit_heads` buffer without resetting them
+            // which causes corrupted linked list(can have circular references) on the next pass
+            let Some(oit_resolve_pipeline_id) = oit_resolve_pipeline_id else {
+                return;
+            };
+            let pipeline_cache = world.resource::<PipelineCache>();
+            if pipeline_cache
+                .get_render_pipeline(oit_resolve_pipeline_id.0)
+                .is_none()
+            {
+                return;
+            }
+        }
+
         let mut render_pass = ctx.begin_tracked_render_pass(RenderPassDescriptor {
             label: Some("main_transparent_pass_3d"),
             color_attachments: &[Some(target.get_color_attachment())],