(wip) deferred SSR

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Debug/DebugDisplay.hlsl

 CBUFFER_END
 
 TEXTURE2D(_DebugFont); // Debug font to write string in shader
-RWStructuredBuffer<ScreenSpaceTracingDebug> _DebugScreenSpaceTracingData : register(u7);
+RWStructuredBuffer<ScreenSpaceTracingDebug> _DebugScreenSpaceTracingData : register(u7); // TODO: Change the register number for PS4
 
 void GetPropertiesDataDebug(uint paramId, inout float3 result, inout bool needLinearToSRGB)
 {

ScriptableRenderPipeline/HDRenderPipeline/HDRP/HDRenderPipeline.cs

             
             m_DebugScreenSpaceTracingData.Release();
 
-            HDCamera.CleanUnused();
+            HDCamera.ClearAll();
         }
 
 
             {
                 // Output split lighting for materials asking for it (masked in the stencil buffer)
                 options.outputSplitLighting = true;
-
-                m_LightLoop.RenderDeferredLighting(hdCamera, cmd, m_CurrentDebugDisplaySettings, m_MRTCache2, m_CameraDepthStencilBuffer, depthTexture, options);
+                
+                m_LightLoop.RenderDeferredLighting(hdCamera, cmd, m_CurrentDebugDisplaySettings, m_MRTCache2, m_CameraDepthStencilBuffer, depthTexture, options, m_DebugScreenSpaceTracingData);
-            m_LightLoop.RenderDeferredLighting(hdCamera, cmd, m_CurrentDebugDisplaySettings, m_MRTCache2, m_CameraDepthStencilBuffer, depthTexture, options);
+            m_LightLoop.RenderDeferredLighting(hdCamera, cmd, m_CurrentDebugDisplaySettings, m_MRTCache2, m_CameraDepthStencilBuffer, depthTexture, options, m_DebugScreenSpaceTracingData);
         }
 
         void UpdateSkyEnvironment(HDCamera hdCamera, CommandBuffer cmd)

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Lighting/LightLoop/LightLoop.cs

 
         public void RenderDeferredLighting( HDCamera hdCamera, CommandBuffer cmd, DebugDisplaySettings debugDisplaySettings,
                                             RenderTargetIdentifier[] colorBuffers, RenderTargetIdentifier depthStencilBuffer, RenderTargetIdentifier depthTexture,
-                                            LightingPassOptions options)
+                                            LightingPassOptions options, ComputeBuffer debugSSTBuffer)
         {
             cmd.SetGlobalBuffer(HDShaderIDs.g_vLightListGlobal, s_LightList);
 
                         cmd.SetComputeTextureParam(deferredComputeShader, kernel, HDShaderIDs.specularLightingUAV, colorBuffers[0]);
                         cmd.SetComputeTextureParam(deferredComputeShader, kernel, HDShaderIDs.diffuseLightingUAV,  colorBuffers[1]);
 
+                        if (debugDisplaySettings.lightingDebugSettings.debugLightingMode == DebugLightingMode.ScreenSpaceTracingReflection)
+                            cmd.SetComputeBufferParam(deferredComputeShader, kernel, HDShaderIDs._DebugScreenSpaceTracingData, debugSSTBuffer);
+
                         // always do deferred lighting in blocks of 16x16 (not same as tiled light size)
 
                         if (enableFeatureVariants)
                             currentLightingMaterial.SetInt(HDShaderIDs._StencilCmp, (int)CompareFunction.Equal);
                         }
 
+                        var debugSSTThisFrame = debugDisplaySettings.lightingDebugSettings.debugLightingMode == DebugLightingMode.ScreenSpaceTracingReflection;
+                        if (debugSSTThisFrame)
+                            cmd.SetRandomWriteTarget(7, debugSSTBuffer);
+                        if (debugSSTThisFrame)
+                            cmd.ClearRandomWriteTargets();
                     }
                 }
             } // End profiling

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Material/Lit/Lit.hlsl

 
     /*  1 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_PUNCTUAL | MATERIALFEATUREFLAGS_LIT_STANDARD,
     /*  2 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_AREA | MATERIALFEATUREFLAGS_LIT_STANDARD,
-    /*  3 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_ENV | MATERIALFEATUREFLAGS_LIT_STANDARD,
-    /*  4 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_PUNCTUAL | LIGHTFEATUREFLAGS_ENV | MATERIALFEATUREFLAGS_LIT_STANDARD,
+    /*  3 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_ENV | LIGHTFEATUREFLAGS_SSREFLECTION | MATERIALFEATUREFLAGS_LIT_STANDARD,
+    /*  4 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_PUNCTUAL | LIGHTFEATUREFLAGS_ENV | LIGHTFEATUREFLAGS_SSREFLECTION | MATERIALFEATUREFLAGS_LIT_STANDARD,
-    /*  8 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_ENV | MATERIALFEATUREFLAGS_LIT_SUBSURFACE_SCATTERING | MATERIALFEATUREFLAGS_LIT_TRANSMISSION | MATERIALFEATUREFLAGS_LIT_STANDARD,
-    /*  9 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_PUNCTUAL | LIGHTFEATUREFLAGS_ENV | MATERIALFEATUREFLAGS_LIT_SUBSURFACE_SCATTERING | MATERIALFEATUREFLAGS_LIT_TRANSMISSION | MATERIALFEATUREFLAGS_LIT_STANDARD,
+    /*  8 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_ENV | LIGHTFEATUREFLAGS_SSREFLECTION | MATERIALFEATUREFLAGS_LIT_SUBSURFACE_SCATTERING | MATERIALFEATUREFLAGS_LIT_TRANSMISSION | MATERIALFEATUREFLAGS_LIT_STANDARD,
+    /*  9 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_PUNCTUAL | LIGHTFEATUREFLAGS_ENV | LIGHTFEATUREFLAGS_SSREFLECTION | MATERIALFEATUREFLAGS_LIT_SUBSURFACE_SCATTERING | MATERIALFEATUREFLAGS_LIT_TRANSMISSION | MATERIALFEATUREFLAGS_LIT_STANDARD,
-    /* 13 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_ENV | MATERIALFEATUREFLAGS_LIT_ANISOTROPY | MATERIALFEATUREFLAGS_LIT_STANDARD,
-    /* 14 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_PUNCTUAL | LIGHTFEATUREFLAGS_ENV | MATERIALFEATUREFLAGS_LIT_ANISOTROPY | MATERIALFEATUREFLAGS_LIT_STANDARD,
+    /* 13 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_ENV | LIGHTFEATUREFLAGS_SSREFLECTION | MATERIALFEATUREFLAGS_LIT_ANISOTROPY | MATERIALFEATUREFLAGS_LIT_STANDARD,
+    /* 14 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_PUNCTUAL | LIGHTFEATUREFLAGS_ENV | LIGHTFEATUREFLAGS_SSREFLECTION | MATERIALFEATUREFLAGS_LIT_ANISOTROPY | MATERIALFEATUREFLAGS_LIT_STANDARD,
-    /* 18 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_ENV | MATERIALFEATUREFLAGS_LIT_CLEAR_COAT | MATERIALFEATUREFLAGS_LIT_STANDARD,
-    /* 19 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_PUNCTUAL | LIGHTFEATUREFLAGS_ENV | MATERIALFEATUREFLAGS_LIT_CLEAR_COAT | MATERIALFEATUREFLAGS_LIT_STANDARD,
+    /* 18 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_ENV | LIGHTFEATUREFLAGS_SSREFLECTION | MATERIALFEATUREFLAGS_LIT_CLEAR_COAT | MATERIALFEATUREFLAGS_LIT_STANDARD,
+    /* 19 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_PUNCTUAL | LIGHTFEATUREFLAGS_ENV | LIGHTFEATUREFLAGS_SSREFLECTION | MATERIALFEATUREFLAGS_LIT_CLEAR_COAT | MATERIALFEATUREFLAGS_LIT_STANDARD,
-    /* 23 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_ENV | MATERIALFEATUREFLAGS_LIT_IRIDESCENCE | MATERIALFEATUREFLAGS_LIT_STANDARD,
-    /* 24 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_PUNCTUAL | LIGHTFEATUREFLAGS_ENV | MATERIALFEATUREFLAGS_LIT_IRIDESCENCE | MATERIALFEATUREFLAGS_LIT_STANDARD,
+    /* 23 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_ENV | LIGHTFEATUREFLAGS_SSREFLECTION | MATERIALFEATUREFLAGS_LIT_IRIDESCENCE | MATERIALFEATUREFLAGS_LIT_STANDARD,
+    /* 24 */ LIGHTFEATUREFLAGS_SKY | LIGHTFEATUREFLAGS_DIRECTIONAL | LIGHTFEATUREFLAGS_PUNCTUAL | LIGHTFEATUREFLAGS_ENV | LIGHTFEATUREFLAGS_SSREFLECTION | MATERIALFEATUREFLAGS_LIT_IRIDESCENCE | MATERIALFEATUREFLAGS_LIT_STANDARD,
     /* 25 */ LIGHT_FEATURE_MASK_FLAGS_OPAQUE | MATERIALFEATUREFLAGS_LIT_IRIDESCENCE | MATERIALFEATUREFLAGS_LIT_STANDARD,
 
     /* 26 */ LIGHT_FEATURE_MASK_FLAGS_OPAQUE | MATERIAL_FEATURE_MASK_FLAGS, // Catch all case with MATERIAL_FEATURE_MASK_FLAGS is needed in case we disable material classification