Add color clear pass while rendering XR occlusion mesh to avoid leaks

com.unity.render-pipelines.high-definition/CHANGELOG.md

@@ -805,6 +805,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Increased path tracing BSDFs roughness range from [0.001, 0.999] to [0.00001, 0.99999].
 - Changing the default SSGI radius for the all configurations.
 - Changed the default parameters for quality RTGI to match expected behavior.
+- Add color clear pass while rendering XR occlusion mesh to avoid leaks.
 
 ## [7.1.1] - 2019-09-05
 

com.unity.render-pipelines.high-definition/Runtime/RenderPipeline/HDRenderPipeline.Prepass.cs

@@ -115,7 +115,8 @@ PrepassOutput RenderPrepass(RenderGraph renderGraph, TextureHandle sssBuffer, Cu
             result.motionVectorsBuffer = CreateMotionVectorBuffer(renderGraph, msaa, clearMotionVectors);
             result.depthBuffer = CreateDepthBuffer(renderGraph, msaa);
 
-            RenderXROcclusionMeshes(renderGraph, hdCamera, result.depthBuffer);
+            // TODO RENDERGRAPH : XR occlusion mesh also need to write to color buffer
+            //RenderXROcclusionMeshes(renderGraph, hdCamera, result.depthBuffer);
 
             using (new XRSinglePassScope(renderGraph, hdCamera))
             {

com.unity.render-pipelines.high-definition/Runtime/RenderPipeline/HDRenderPipeline.RenderGraphUtils.cs

@@ -143,7 +143,8 @@ void RenderXROcclusionMeshes(RenderGraph renderGraph, HDCamera hdCamera, Texture
                     builder.SetRenderFunc(
                     (RenderOcclusionMeshesPassData data, RenderGraphContext ctx) =>
                     {
-                        data.hdCamera.xr.RenderOcclusionMeshes(ctx.cmd, ctx.resources.GetTexture(data.depthBuffer));
+                        // TODO RENDERGRAPH : XR occlusion mesh also need to write to color buffer
+                        //data.hdCamera.xr.RenderOcclusionMeshes(ctx.cmd, ctx.resources.GetTexture(data.depthBuffer));
                     });
                 }
             }

com.unity.render-pipelines.high-definition/Runtime/RenderPipeline/HDRenderPipeline.cs

@@ -2351,8 +2351,11 @@ AOVRequestData aovRequest
             // Render XR occlusion mesh to depth buffer early in the frame to improve performance
             if (hdCamera.xr.enabled && m_Asset.currentPlatformRenderPipelineSettings.xrSettings.occlusionMesh)
             {
+                bool msaa = hdCamera.frameSettings.IsEnabled(FrameSettingsField.MSAA);
+                Color clearColor = GetColorBufferClearColor(hdCamera);
+
                 hdCamera.xr.StopSinglePass(cmd);
-                hdCamera.xr.RenderOcclusionMeshes(cmd, m_SharedRTManager.GetDepthStencilBuffer(hdCamera.frameSettings.IsEnabled(FrameSettingsField.MSAA)));
+                hdCamera.xr.RenderOcclusionMeshes(cmd, clearColor, msaa ? m_CameraColorMSAABuffer : m_CameraColorBuffer, m_SharedRTManager.GetDepthStencilBuffer(msaa));
                 hdCamera.xr.StartSinglePass(cmd);
             }
 

com.unity.render-pipelines.high-definition/Runtime/RenderPipeline/HDStringConstants.cs

@@ -186,6 +186,7 @@ static class HDShaderIDs
 
         public static readonly int _InputDepth = Shader.PropertyToID("_InputDepthTexture");
 
+        public static readonly int _ClearColor = Shader.PropertyToID("_ClearColor");
         public static readonly int _SrcBlend = Shader.PropertyToID("_SrcBlend");
         public static readonly int _DstBlend = Shader.PropertyToID("_DstBlend");
 

com.unity.render-pipelines.high-definition/Runtime/RenderPipeline/XR/XRPass.cs

@@ -255,7 +255,7 @@ internal void EndCamera(CommandBuffer cmd, HDCamera hdCamera)
             }
         }
 
-        internal void RenderOcclusionMeshes(CommandBuffer cmd, RTHandle depthBuffer)
+        internal void RenderOcclusionMeshes(CommandBuffer cmd, Color clearColor, RTHandle colorBuffer, RTHandle depthBuffer)
         {
             if (enabled && xrSdkEnabled && occlusionMeshMaterial != null)
             {
@@ -267,7 +267,8 @@ internal void RenderOcclusionMeshes(CommandBuffer cmd, RTHandle depthBuffer)
                     {
                         if (views[viewId].occlusionMesh != null)
                         {
-                            CoreUtils.SetRenderTarget(cmd, depthBuffer, ClearFlag.None, 0, CubemapFace.Unknown, viewId);
+                            CoreUtils.SetRenderTarget(cmd, colorBuffer, depthBuffer, ClearFlag.None, clearColor, 0, CubemapFace.Unknown, viewId);
+                            cmd.SetGlobalVector(HDShaderIDs._ClearColor, clearColor);
                             cmd.DrawMesh(views[viewId].occlusionMesh, m, occlusionMeshMaterial);
                         }
                     }

com.unity.render-pipelines.high-definition/Runtime/ShaderLibrary/XROcclusionMesh.shader

@@ -23,8 +23,11 @@ Shader "Hidden/HDRP/XROcclusionMesh"
             return output;
         }
 
-        void Frag(out float outputDepth : SV_Depth)
+        float4 _ClearColor;
+
+        void Frag(out float4 outputColor : SV_Target, out float outputDepth : SV_Depth)
         {
+            outputColor = _ClearColor;
             outputDepth = UNITY_NEAR_CLIP_VALUE;
         }
     ENDHLSL
@@ -36,7 +39,6 @@ Shader "Hidden/HDRP/XROcclusionMesh"
         Pass
         {
             ZWrite On ZTest Always Blend Off Cull Off
-            ColorMask 0
 
             HLSLPROGRAM
                 #pragma vertex Vert