Revert various change, as RenderTexture are needed for UAV + fix issue in Jimenez

ScriptableRenderPipeline/HDRenderPipeline/HDRenderPipeline.cs

             bool resolutionChanged = camera.pixelWidth != m_CurrentWidth || camera.pixelHeight != m_CurrentHeight;
 
             if (resolutionChanged || m_CameraDepthStencilBuffer == null)
+            {
+                m_SSSBufferManager.Resize(camera);
+            }
 
             if (resolutionChanged || m_LightLoop.NeedResize())
             {

ScriptableRenderPipeline/HDRenderPipeline/HDStringConstants.cs

         public static readonly int _SrcBlend = Shader.PropertyToID("_SrcBlend");
         public static readonly int _DstBlend = Shader.PropertyToID("_DstBlend");
 
+        public static readonly int _HTile = Shader.PropertyToID("_HTile");
         public static readonly int _SSSHTile = Shader.PropertyToID("_SSSHTile");
         public static readonly int _StencilTexture = Shader.PropertyToID("_StencilTexture");
 

ScriptableRenderPipeline/HDRenderPipeline/Material/SubsurfaceScattering/SubsurfaceScatteringManager.cs

         ComputeShader m_SubsurfaceScatteringCS;
         int m_SubsurfaceScatteringKernel;
         Material m_CombineLightingPass;
-        readonly int m_SSSHTileBuffer;
-        readonly RenderTargetIdentifier m_SSSHTileBufferRT;
+
+        RenderTexture m_HTile;
+        RenderTargetIdentifier m_HTileRT;
-        // Jimenez on some platform need an extra buffer
+        // End Jimenez SSS Model
+
+        // Jimenez need an extra buffer and Disney need one for some platform
-        // End Jimenez SSS Model
 
         // This is use to be able to read stencil value in compute shader
         Material m_CopyStencilForSplitLighting;
         public SubsurfaceScatteringManager()
         {
             m_SSSBuffer0RT = new RenderTargetIdentifier(m_SSSBuffer0);
-
-            // Use with Disney
-            m_SSSHTileBuffer = HDShaderIDs._SSSHTile;
-            m_SSSHTileBufferRT = new RenderTargetIdentifier(m_SSSHTileBuffer);
 
             // Use with Jimenez
             m_CameraFilteringBuffer = HDShaderIDs._CameraFilteringBuffer;
             CoreUtils.Destroy(m_CopyStencilForSplitLighting);
         }
 
+        public void Resize(Camera camera)
+        {
+            // We must use a RenderTexture and not GetTemporaryRT() as currently Unity only aloow to bind a RenderTexture for a UAV in a pixel shader
+            // We use 8x8 tiles in order to match the native GCN HTile as closely as possible.
+            m_HTile = new RenderTexture((camera.pixelWidth + 7) / 8, (camera.pixelHeight + 7) / 8, 0, RenderTextureFormat.R8, RenderTextureReadWrite.Linear); // DXGI_FORMAT_R8_UINT is not supported by Unity
+            m_HTile.filterMode = FilterMode.Point;
+            m_HTile.enableRandomWrite = true;
+            m_HTile.Create();
+            m_HTileRT = new RenderTargetIdentifier(m_HTile);
+        }
+
+            // Caution: need to be in sync with SubsurfaceScattering.cs USE_INTERMEDIATE_BUFFER (Can't make a keyword as it is a compute shader)
-            return  SystemInfo.graphicsDeviceType != GraphicsDeviceType.PlayStation4 &&
+            return SystemInfo.graphicsDeviceType != GraphicsDeviceType.PlayStation4 &&
                     SystemInfo.graphicsDeviceType != GraphicsDeviceType.XboxOne &&
                     SystemInfo.graphicsDeviceType != GraphicsDeviceType.XboxOneD3D12;
         }
 
             using (new ProfilingSample(cmd, "Subsurface Scattering", HDRenderPipeline.GetSampler(CustomSamplerId.SubsurfaceScattering)))
             {
-                if (m_sssSettings.useDisneySSS)
+                int w = hdCamera.camera.pixelWidth;
+                int h = hdCamera.camera.pixelHeight;
+
+                // For Jimenez we always need an extra buffer, for Disney it depends on platform
+                if (!m_sssSettings.useDisneySSS ||
+                    (m_sssSettings.useDisneySSS && NeedTemporarySubsurfaceBuffer()))
-                    int w = hdCamera.camera.pixelWidth;
-                    int h = hdCamera.camera.pixelHeight;
+                    // Caution: must be same format as m_CameraSssDiffuseLightingBuffer
+                    cmd.ReleaseTemporaryRT(m_CameraFilteringBuffer);
+                    cmd.GetTemporaryRT(m_CameraFilteringBuffer, w, h, 0, FilterMode.Point, RenderTextureFormat.RGB111110Float, RenderTextureReadWrite.Linear, 1, true); // Enable UAV
+                                                                                                                                                                        // Clear the SSS filtering target
+                    using (new ProfilingSample(cmd, "Clear SSS filtering target", HDRenderPipeline.GetSampler(CustomSamplerId.ClearSSSFilteringTarget)))
+                    {
+                        CoreUtils.SetRenderTarget(cmd, m_CameraFilteringBufferRT, ClearFlag.Color, CoreUtils.clearColorAllBlack);
+                    }
+                }
+                if (m_sssSettings.useDisneySSS)
+                {
+                        CoreUtils.SetRenderTarget(cmd, m_HTileRT, ClearFlag.Color, CoreUtils.clearColorAllBlack);
-                        // Caution: must be same format as m_CameraSssDiffuseLightingBuffer
-                        cmd.ReleaseTemporaryRT(m_SSSHTileBuffer);
-                        // Note: DXGI_FORMAT_R8_UINT is not supported by Unity
-                        // We use 8x8 tiles in order to match the native GCN HTile as closely as possible.
-                        cmd.GetTemporaryRT(m_SSSHTileBuffer, (w + 7) / 8, (h + 7) / 8, 0, FilterMode.Point, RenderTextureFormat.R8, RenderTextureReadWrite.Linear, 1, true); // Enable UAV
-
-                        CoreUtils.SetRenderTarget(cmd, m_SSSHTileBufferRT, ClearFlag.Color, CoreUtils.clearColorAllBlack);
-
-                        cmd.SetRandomWriteTarget(1, m_SSSHTileBufferRT);
+                        cmd.SetRandomWriteTarget(1, m_HTile);
                         // Generate HTile for the split lighting stencil usage. Don't write into stencil texture (shaderPassId = 2)
                         // Use ShaderPassID 1 => "Pass 2 - Export HTILE for stencilRef to output"
                         CoreUtils.SetRenderTarget(cmd, depthStencilBufferRT); // No need for color buffer here
                     cmd.SetComputeVectorArrayParam(m_SubsurfaceScatteringCS, HDShaderIDs._ShapeParams,        sssParameters.shapeParams);
 
                     cmd.SetComputeTextureParam(m_SubsurfaceScatteringCS, m_SubsurfaceScatteringKernel, HDShaderIDs._DepthTexture,       depthTextureRT);
-                    cmd.SetComputeTextureParam(m_SubsurfaceScatteringCS, m_SubsurfaceScatteringKernel, HDShaderIDs._SSSHTile,           m_SSSHTileBufferRT);
+                    cmd.SetComputeTextureParam(m_SubsurfaceScatteringCS, m_SubsurfaceScatteringKernel, HDShaderIDs._SSSHTile,           m_HTileRT);
                     cmd.SetComputeTextureParam(m_SubsurfaceScatteringCS, m_SubsurfaceScatteringKernel, HDShaderIDs._IrradianceSource,   diffuseBufferRT);
 
                     for (int i = 0; i < sssBufferCount; ++i)