Merge pull request #144 from Unity-Technologies/Branch_CopyDepthPostOpaque

Made a copy of the depth buffer after all opaque so that it can be read during the transparent pass.

Assets/ScriptableRenderLoop/HDRenderPipeline/HDRenderPipeline.asset

   m_Script: {fileID: 11500000, guid: d440c0deec24a2f478b3e9021cb66c29, type: 3}
   m_Name: HDRenderPipeline
   m_EditorClassIdentifier: 
-  m_CommonSettings:
-    m_ShadowMaxDistance: 1000
-    m_ShadowCascadeCount: 4
-    m_ShadowCascadeSplit0: 0.05
-    m_ShadowCascadeSplit1: 0.2
-    m_ShadowCascadeSplit2: 0.3
-    m_SssProfileStdDev1: {r: 0.3, g: 0.3, b: 0.3, a: 0}
-    m_SssProfileStdDev2: {r: 1, g: 1, b: 1, a: 0}
-    m_SssProfileLerpWeight: 0.5
-    m_SssBilateralScale: 0.1
-  m_SkyParameters: {fileID: 0}
-    displayDebug: 1
-    displayShadowDebug: 1
-    shadowDebugParameters:
+    displayMaterialDebug: 1
+    displayRenderingDebug: 1
+    displayLightingDebug: 1
+    materialDebugParameters:
+      debugViewMaterial: 0
+    lightingDebugParameters:
-      visualizationMode: 0
-      visualizeShadowMapIndex: 0
+      shadowDebugMode: 0
+      shadowMapIndex: 0
+      lightingDebugMode: 0
+      overrideSmoothness: 0
+      overrideSmoothnessValue: 0.78
+      debugLightingAlbedo: {r: 0.53676474, g: 0.53676474, b: 0.53676474, a: 1}
+    renderingDebugParametrs:
+      displayOpaqueObjects: 1
+      displayTransparentObjects: 1
+      enableDistortion: 0
+  renderingParameters:
+    useForwardRenderingOnly: 0
+    useDepthPrepass: 0
   m_ShadowSettings:
     enabled: 1
     shadowAtlasWidth: 4096
     directionalLightCascades: {x: 0.05, y: 0.2, z: 0.3}
-  m_SssParameters:
-    profiles: []
-    bilateralScale: 0.1
+  localSssParameters: {fileID: 0}
+  m_CommonSettings:
+    m_ShadowMaxDistance: 1000
+    m_ShadowCascadeCount: 4
+    m_ShadowCascadeSplit0: 0.05
+    m_ShadowCascadeSplit1: 0.2
+    m_ShadowCascadeSplit2: 0.3
+  m_SkyParameters: {fileID: 0}

Assets/ScriptableRenderLoop/HDRenderPipeline/HDRenderPipeline.cs

         readonly int m_CameraSubsurfaceBuffer;
         readonly int m_CameraFilteringBuffer;
         readonly int m_CameraDepthStencilBuffer;
+        readonly int m_CameraDepthStencilBufferCopy; // This is temporary, we will need to provide the correct opaque depth buffer to transparent without needing a copy
         readonly int m_CameraStencilBuffer;
         readonly int m_VelocityBuffer;
         readonly int m_DistortionBuffer;
         readonly RenderTargetIdentifier m_CameraSubsurfaceBufferRT;
         readonly RenderTargetIdentifier m_CameraFilteringBufferRT;
         readonly RenderTargetIdentifier m_CameraDepthStencilBufferRT;
+        readonly RenderTargetIdentifier m_CameraDepthStencilBufferCopyRT;
         // 'm_CameraStencilBufferRT' is a temporary copy of the stencil buffer and should be removed
         // once we are able to read from the depth buffer and perform the stencil test simultaneously.
         readonly RenderTargetIdentifier m_CameraStencilBufferRT;
         {
             m_Owner = owner;
 
-            m_CameraColorBuffer          = Shader.PropertyToID("_CameraColorTexture");
-            m_CameraSubsurfaceBuffer     = Shader.PropertyToID("_CameraSubsurfaceTexture");
-            m_CameraFilteringBuffer      = Shader.PropertyToID("_CameraFilteringBuffer");
-            m_CameraDepthStencilBuffer   = Shader.PropertyToID("_CameraDepthTexture");
-            m_CameraStencilBuffer        = Shader.PropertyToID("_CameraStencilTexture");
+            m_CameraColorBuffer             = Shader.PropertyToID("_CameraColorTexture");
+            m_CameraSubsurfaceBuffer        = Shader.PropertyToID("_CameraSubsurfaceTexture");
+            m_CameraFilteringBuffer         = Shader.PropertyToID("_CameraFilteringBuffer");
+            m_CameraDepthStencilBuffer      = Shader.PropertyToID("_CameraDepthTexture");
+            m_CameraDepthStencilBufferCopy  = Shader.PropertyToID("_CameraDepthTextureCopy");
+            m_CameraStencilBuffer           = Shader.PropertyToID("_CameraStencilTexture");
-            m_CameraColorBufferRT        = new RenderTargetIdentifier(m_CameraColorBuffer);
-            m_CameraSubsurfaceBufferRT   = new RenderTargetIdentifier(m_CameraSubsurfaceBuffer);
-            m_CameraFilteringBufferRT    = new RenderTargetIdentifier(m_CameraFilteringBuffer);
-            m_CameraDepthStencilBufferRT = new RenderTargetIdentifier(m_CameraDepthStencilBuffer);
-            m_CameraStencilBufferRT      = new RenderTargetIdentifier(m_CameraStencilBuffer);
+            m_CameraColorBufferRT               = new RenderTargetIdentifier(m_CameraColorBuffer);
+            m_CameraSubsurfaceBufferRT          = new RenderTargetIdentifier(m_CameraSubsurfaceBuffer);
+            m_CameraFilteringBufferRT           = new RenderTargetIdentifier(m_CameraFilteringBuffer);
+            m_CameraDepthStencilBufferRT        = new RenderTargetIdentifier(m_CameraDepthStencilBuffer);
+            m_CameraDepthStencilBufferCopyRT    = new RenderTargetIdentifier(m_CameraDepthStencilBufferCopy);
+            m_CameraStencilBufferRT             = new RenderTargetIdentifier(m_CameraStencilBuffer);
 
             m_DebugViewMaterialGBuffer = Utilities.CreateEngineMaterial("Hidden/HDRenderPipeline/DebugViewMaterialGBuffer");
 
             // Material that are always forward are unlit and complex (Like Hair) and don't require sorting, so it is ok to split them.
             RenderForward(cullResults, camera, renderContext, true); // Render deferred or forward opaque
             RenderForwardOnlyOpaque(cullResults, camera, renderContext);
+
+            // 'm_CameraDepthStencilBufferCopyRT' is a temporary copy of the depth textureand should be removed
+            // once we are able to read from the depth buffer during transparent pass.
+            using (new Utilities.ProfilingSample("Copy depth-stencil buffer after all opaque", renderContext))
+            {
+                var cmd = new CommandBuffer();
+                cmd.CopyTexture(m_CameraDepthStencilBufferRT, m_CameraDepthStencilBufferCopyRT);
+                renderContext.ExecuteCommandBuffer(cmd);
+                cmd.Dispose();
+            }
 
             RenderSky(hdCamera, renderContext);
 
                     int w = camera.pixelWidth;
                     int h = camera.pixelHeight;
 
-                    cmd.GetTemporaryRT(m_CameraColorBuffer,        w, h,  0, FilterMode.Point, RenderTextureFormat.ARGBHalf,       RenderTextureReadWrite.Linear, 1, true); // Enable UAV
-                    cmd.GetTemporaryRT(m_CameraSubsurfaceBuffer,   w, h,  0, FilterMode.Point, RenderTextureFormat.RGB111110Float, RenderTextureReadWrite.Linear, 1, true); // Enable UAV
-                    cmd.GetTemporaryRT(m_CameraFilteringBuffer,    w, h,  0, FilterMode.Point, RenderTextureFormat.RGB111110Float, RenderTextureReadWrite.Linear, 1, true); // Enable UAV
-                    cmd.GetTemporaryRT(m_CameraDepthStencilBuffer, w, h, 24, FilterMode.Point, RenderTextureFormat.Depth);
-                    cmd.GetTemporaryRT(m_CameraStencilBuffer,      w, h, 24, FilterMode.Point, RenderTextureFormat.Depth);
+                    cmd.GetTemporaryRT(m_CameraColorBuffer,             w, h,  0, FilterMode.Point, RenderTextureFormat.ARGBHalf,       RenderTextureReadWrite.Linear, 1, true); // Enable UAV
+                    cmd.GetTemporaryRT(m_CameraSubsurfaceBuffer,        w, h,  0, FilterMode.Point, RenderTextureFormat.RGB111110Float, RenderTextureReadWrite.Linear, 1, true); // Enable UAV
+                    cmd.GetTemporaryRT(m_CameraFilteringBuffer,         w, h,  0, FilterMode.Point, RenderTextureFormat.RGB111110Float, RenderTextureReadWrite.Linear, 1, true); // Enable UAV
+                    cmd.GetTemporaryRT(m_CameraDepthStencilBuffer,      w, h, 24, FilterMode.Point, RenderTextureFormat.Depth);
+                    cmd.GetTemporaryRT(m_CameraDepthStencilBufferCopy,  w, h, 24, FilterMode.Point, RenderTextureFormat.Depth);
+                    cmd.GetTemporaryRT(m_CameraStencilBuffer,           w, h, 24, FilterMode.Point, RenderTextureFormat.Depth);
 
                     if (!m_Owner.renderingParameters.ShouldUseForwardRenderingOnly())
                     {

Assets/ScriptableRenderLoop/HDRenderPipeline/ShaderVariables.hlsl

 	float4 unity_SHC;
 CBUFFER_END
 
+// Use the regular depth camera texture sampler for sampling this: sampler_CameraDepthTexture
+TEXTURE2D_FLOAT(_CameraDepthTextureCopy);
+SAMPLER2D(sampler_CameraDepthTextureCopy);
+
 // Main lightmap
 TEXTURE2D(unity_Lightmap);
 SAMPLER2D(samplerunity_Lightmap);