Various code cleanup in HDRP indirect diffuse lighting + Start remove macro RAYTRACING

TestProjects/HDRP_DXR_Tests/LocalPackages/com.unity.render-pipelines.high-definition-config/Runtime/ShaderConfig.cs.hlsl

@@ -4,13 +4,6 @@
 
 #ifndef SHADERCONFIG_CS_HLSL
 #define SHADERCONFIG_CS_HLSL
-//
-// UnityEngine.Rendering.HighDefinition.HDShadowFilteringQuality:  static fields
-//
-#define HDSHADOWFILTERINGQUALITY_LOW (0)
-#define HDSHADOWFILTERINGQUALITY_MEDIUM (1)
-#define HDSHADOWFILTERINGQUALITY_HIGH (2)
-
 //
 // UnityEngine.Rendering.HighDefinition.ProbeVolumesEvaluationModes:  static fields
 //
@@ -45,7 +38,6 @@
 #define SHADEROPTIONS_PROBE_VOLUMES_BILATERAL_FILTERING_MODE (1)
 #define SHADEROPTIONS_PROBE_VOLUMES_ENCODING_MODE (1)
 #define SHADEROPTIONS_AREA_LIGHTS (1)
-#define SHADEROPTIONS_DEFERRED_SHADOW_FILTERING (1)
 #define SHADEROPTIONS_BARN_DOOR (0)
 
 

com.unity.render-pipelines.high-definition/Runtime/Lighting/LightEvaluation.hlsl

@@ -526,20 +526,17 @@ void EvaluateLight_EnvIntersection(float3 positionWS, float3 normalWS, EnvLightD
 
 void InversePreExposeSsrLighting(inout float4 ssrLighting)
 {
-    float prevExposureInvMultiplier = GetInversePreviousExposureMultiplier();
-
-#if SHADEROPTIONS_RAYTRACING
-    if (!_UseRayTracedReflections)
-#endif
-    ssrLighting.rgb *= prevExposureInvMultiplier;
+    // Raytrace reflection use the current frame exposure - TODO: currently the buffer don't use pre-exposure.
+    // Screen space reflection reuse color buffer from previous frame
+    float exposureMultiplier = _EnableRayTracedReflections ? 1.0 : GetInversePreviousExposureMultiplier();
+    ssrLighting.rgb *= exposureMultiplier;
 }
 
 void ApplyScreenSpaceReflectionWeight(inout float4 ssrLighting)
 {
     // Note: RGB is already premultiplied by A for SSR
-#if SHADEROPTIONS_RAYTRACING
-    if (_UseRayTracedReflections)
-        ssrLighting.rgb *= ssrLighting.a;
-#endif
+    // TODO: check why it isn't consistent between SSR and RTR
+    float weight = _EnableRayTracedReflections ? 1.0 : ssrLighting.a;
+    ssrLighting.rgb *= ssrLighting.a;
 }
 #endif

com.unity.render-pipelines.high-definition/Runtime/Lighting/LightLoop/LightLoop.cs

@@ -121,11 +121,6 @@ class LightDefinitions
         public static uint s_ScreenSpaceColorShadowFlag = 0x100;
         public static uint s_InvalidScreenSpaceShadow = 0xff;
         public static uint s_ScreenSpaceShadowIndexMask = 0xff;
-
-        // Indirect diffuse flags
-        public static int k_IndirectDiffuseFlagOff = 0x00;
-        public static int k_ScreenSpaceIndirectDiffuseFlag = 0x01;
-        public static int k_RayTracedIndirectDiffuseFlag = 0x02;
     }
 
     [GenerateHLSL]

com.unity.render-pipelines.high-definition/Runtime/Lighting/LightLoop/LightLoop.cs.hlsl

@@ -59,9 +59,6 @@
 #define SCREEN_SPACE_COLOR_SHADOW_FLAG (256)
 #define INVALID_SCREEN_SPACE_SHADOW (255)
 #define SCREEN_SPACE_SHADOW_INDEX_MASK (255)
-#define INDIRECT_DIFFUSE_FLAG_OFF (0)
-#define SCREEN_SPACE_INDIRECT_DIFFUSE_FLAG (1)
-#define RAY_TRACED_INDIRECT_DIFFUSE_FLAG (2)
 
 // Generated from UnityEngine.Rendering.HighDefinition.SFiniteLightBound
 // PackingRules = Exact

com.unity.render-pipelines.high-definition/Runtime/Lighting/LightLoop/LightLoop.hlsl

@@ -2,6 +2,9 @@
 
 #if SHADEROPTIONS_PROBE_VOLUMES_EVALUATION_MODE == PROBEVOLUMESEVALUATIONMODES_LIGHT_LOOP
 #include "Packages/com.unity.render-pipelines.high-definition/Runtime/Material/BuiltinUtilities.hlsl"
+#else
+// Required to have access to the indirectDiffuseMode enum in forward pass where we don't include BuiltinUtilities
+#include "Packages/com.unity.render-pipelines.high-definition/Runtime/Lighting/ScreenSpaceLighting/ScreenSpaceGlobalIllumination.cs.hlsl"
 #endif
 
 // We perform scalarization only for forward rendering as for deferred loads will already be scalar since tiles will match waves and therefore all threads will read from the same tile.
@@ -534,15 +537,23 @@ void LightLoop( float3 V, PositionInputs posInput, PreLightData preLightData, BS
 
 #if !defined(_SURFACE_TYPE_TRANSPARENT)
     // If we use the texture ssgi for ssgi or rtgi, we want to combine it with the value in the bake diffuse lighting value
-    if (_UseIndirectDiffuse != INDIRECT_DIFFUSE_FLAG_OFF)
+    if (_IndirectDiffuseMode != INDIRECTDIFFUSEMODE_OFF)
     {
-        BuiltinData builtInDataSSGI;
-        ZERO_INITIALIZE(BuiltinData, builtInDataSSGI);
-        builtInDataSSGI.bakeDiffuseLighting = LOAD_TEXTURE2D_X(_IndirectDiffuseTexture, posInput.positionSS).xyz * GetInverseCurrentExposureMultiplier();
-        float indirectDiffuseMultiplier = GetIndirectDiffuseMultiplier(builtinData.renderingLayers);
-        builtInDataSSGI.bakeDiffuseLighting *= indirectDiffuseMultiplier;
-        ModifyBakedDiffuseLighting(V, posInput, preLightData, bsdfData, builtInDataSSGI);
-        builtinData.bakeDiffuseLighting += builtInDataSSGI.bakeDiffuseLighting;
+        BuiltinData builtinDataSSGI;
+        ZERO_INITIALIZE(BuiltinData, builtinDataSSGI);
+        builtinDataSSGI.bakeDiffuseLighting = LOAD_TEXTURE2D_X(_IndirectDiffuseTexture, posInput.positionSS).xyz * GetInverseCurrentExposureMultiplier();
+        builtinDataSSGI.bakeDiffuseLighting *= GetIndirectDiffuseMultiplier(builtinData.renderingLayers);
+
+        // TODO: try to see if we can share code with probe volume
+#ifdef MODIFY_BAKED_DIFFUSE_LIGHTING
+#ifdef DEBUG_DISPLAY
+        // When the lux meter is enabled, we don't want the albedo of the material to modify the diffuse baked lighting
+        if (_DebugLightingMode != DEBUGLIGHTINGMODE_LUX_METER)
+#endif
+            ModifyBakedDiffuseLighting(V, posInput, preLightData, bsdfData, builtinDataSSGI);
+
+#endif
+        builtinData.bakeDiffuseLighting += builtinDataSSGI.bakeDiffuseLighting;
     }
 #endif
 

com.unity.render-pipelines.high-definition/Runtime/Lighting/ScreenSpaceLighting/ScreenSpaceGlobalIllumination.cs

@@ -2,6 +2,15 @@
 
 namespace UnityEngine.Rendering.HighDefinition
 {
+    [GenerateHLSL]
+    // Define if we use SSGI, RTGI or none
+    enum IndirectDiffuseMode
+    {
+        Off,
+        ScreenSpace,
+        Raytrace
+    }
+
     public partial class HDRenderPipeline
     {
         // Buffers used for the evaluation
@@ -52,13 +61,21 @@ void ReleaseScreenSpaceGlobalIllumination()
         }
 
         // This is shared between SSGI and RTGI
-        bool ValidIndirectDiffuseState(HDCamera hdCamera)
+        IndirectDiffuseMode GetIndirectDiffuseMode(HDCamera hdCamera)
         {
-            var settings = hdCamera.volumeStack.GetComponent<GlobalIllumination>();
-            return m_Asset.currentPlatformRenderPipelineSettings.supportSSGI
-                    && hdCamera.camera.cameraType != CameraType.Reflection
-                    && hdCamera.frameSettings.IsEnabled(FrameSettingsField.SSGI)
-                    && settings.enable.value;
+            IndirectDiffuseMode mode = IndirectDiffuseMode.Off;
+
+            if (hdCamera.frameSettings.IsEnabled(FrameSettingsField.SSGI))
+            {
+                var settings = hdCamera.volumeStack.GetComponent<GlobalIllumination>();
+                if (settings.enable.value)
+                {
+                    // RTGI is only valid if raytracing is enabled
+                    bool raytracing = hdCamera.frameSettings.IsEnabled(FrameSettingsField.RayTracing) && settings.rayTracing.value;
+                    mode = raytracing ? IndirectDiffuseMode.Raytrace : IndirectDiffuseMode.ScreenSpace;
+                }
+            }
+            return mode;
         }
 
         // Bind the indirect diffuse texture for the lightloop to read from it

com.unity.render-pipelines.high-definition/Runtime/Lighting/ScreenSpaceLighting/ScreenSpaceGlobalIllumination.cs.hlsl

@@ -0,0 +1,15 @@
+//
+// This file was automatically generated. Please don't edit by hand.
+//
+
+#ifndef SCREENSPACEGLOBALILLUMINATION_CS_HLSL
+#define SCREENSPACEGLOBALILLUMINATION_CS_HLSL
+//
+// UnityEngine.Rendering.HighDefinition.IndirectDiffuseMode:  static fields
+//
+#define INDIRECTDIFFUSEMODE_OFF (0)
+#define INDIRECTDIFFUSEMODE_SCREEN_SPACE (1)
+#define INDIRECTDIFFUSEMODE_RAYTRACE (2)
+
+
+#endif

com.unity.render-pipelines.high-definition/Runtime/Material/BuiltinGIUtilities.hlsl

@@ -1,6 +1,9 @@
 #ifndef __BUILTINGIUTILITIES_HLSL__
 #define __BUILTINGIUTILITIES_HLSL__
 
+// Include the IndirectDiffuseMode enum
+#include "Packages/com.unity.render-pipelines.high-definition/Runtime/Lighting/ScreenSpaceLighting/ScreenSpaceGlobalIllumination.cs.hlsl"
+
 #ifdef SHADERPASS
 #if ((SHADEROPTIONS_PROBE_VOLUMES_EVALUATION_MODE == PROBEVOLUMESEVALUATIONMODES_MATERIAL_PASS) && (SHADERPASS == SHADERPASS_GBUFFER || SHADERPASS == SHADERPASS_FORWARD)) || \
      ((SHADEROPTIONS_PROBE_VOLUMES_EVALUATION_MODE == PROBEVOLUMESEVALUATIONMODES_LIGHT_LOOP) && (SHADERPASS == SHADERPASS_DEFERRED_LIGHTING || SHADERPASS == SHADERPASS_FORWARD))
@@ -83,14 +86,8 @@ void EvaluateLightProbeBuiltin(float3 positionRWS, float3 normalWS, float3 backN
     }
     else
     {
-#if RAYTRACING_ENABLED
-        if (unity_ProbeVolumeParams.w == 1.0)
-            SampleProbeVolumeSH9(TEXTURE3D_ARGS(unity_ProbeVolumeSH, samplerunity_ProbeVolumeSH), positionRWS, normalWS, backNormalWS, GetProbeVolumeWorldToObject(),
-                unity_ProbeVolumeParams.y, unity_ProbeVolumeParams.z, unity_ProbeVolumeMin.xyz, unity_ProbeVolumeSizeInv.xyz, bakeDiffuseLighting, backBakeDiffuseLighting);
-        else
-#endif
-            SampleProbeVolumeSH4(TEXTURE3D_ARGS(unity_ProbeVolumeSH, samplerunity_ProbeVolumeSH), positionRWS, normalWS, backNormalWS, GetProbeVolumeWorldToObject(),
-                unity_ProbeVolumeParams.y, unity_ProbeVolumeParams.z, unity_ProbeVolumeMin.xyz, unity_ProbeVolumeSizeInv.xyz, bakeDiffuseLighting, backBakeDiffuseLighting);
+        SampleProbeVolumeSH4(TEXTURE3D_ARGS(unity_ProbeVolumeSH, samplerunity_ProbeVolumeSH), positionRWS, normalWS, backNormalWS, GetProbeVolumeWorldToObject(),
+            unity_ProbeVolumeParams.y, unity_ProbeVolumeParams.z, unity_ProbeVolumeMin.xyz, unity_ProbeVolumeSizeInv.xyz, bakeDiffuseLighting, backBakeDiffuseLighting);
     }
 }
 
@@ -105,16 +102,25 @@ void SampleBakedGI(
     out float3 bakeDiffuseLighting,
     out float3 backBakeDiffuseLighting)
 {
+    bakeDiffuseLighting = float3(0, 0, 0);
+    backBakeDiffuseLighting = float3(0, 0, 0);
+
+    // Check if we are RTGI in which case we don't want to read GI at all (We rely fully on the raytrace effect)
+    // The check need to be here to work with both regular shader and shader graph
+    // Note: with Probe volume it will prevent to add the UNINITIALIZED_GI tag and
+    // the ProbeVolume will not be evaluate in the lightloop which is the desired behavior
+#if !defined(_SURFACE_TYPE_TRANSPARENT)
+    if (_IndirectDiffuseMode == INDIRECTDIFFUSEMODE_RAYTRACE)
+        return ;
+#endif
+
     float3 positionRWS = posInputs.positionWS;
 
 #define SAMPLE_LIGHTMAP (defined(LIGHTMAP_ON) || defined(DYNAMICLIGHTMAP_ON))
 #define SAMPLE_PROBEVOLUME (SHADEROPTIONS_PROBE_VOLUMES_EVALUATION_MODE == PROBEVOLUMESEVALUATIONMODES_MATERIAL_PASS) \
     && (!SAMPLE_LIGHTMAP || SHADEROPTIONS_PROBE_VOLUMES_ADDITIVE_BLENDING)
 #define SAMPLE_PROBEVOLUME_BUILTIN (!SAMPLE_LIGHTMAP && !SAMPLE_PROBEVOLUME)
 
-    bakeDiffuseLighting = float3(0, 0, 0);
-    backBakeDiffuseLighting = float3(0, 0, 0);
-
 #if SAMPLE_LIGHTMAP
     EvaluateLightmap(positionRWS, normalWS, backNormalWS, uvStaticLightmap, uvDynamicLightmap, bakeDiffuseLighting, backBakeDiffuseLighting);
 #endif

com.unity.render-pipelines.high-definition/Runtime/Material/BuiltinUtilities.hlsl

@@ -46,16 +46,6 @@ void InitBuiltinData(PositionInputs posInput, float alpha, float3 normalWS, floa
     builtinData.backBakeDiffuseLighting = 0.0;
     SampleBakedGI(  posInput, normalWS, backNormalWS, builtinData.renderingLayers, texCoord1.xy, texCoord2.xy,
                     builtinData.bakeDiffuseLighting, builtinData.backBakeDiffuseLighting);
-
-    // We only want to read the screen space buffer that holds the indirect diffuse signal if this is not a transparent surface
-#if RAYTRACING_ENABLED && ((SHADERPASS == SHADERPASS_GBUFFER) || (SHADERPASS == SHADERPASS_FORWARD)) && !defined(_SURFACE_TYPE_TRANSPARENT)
-    if (_UseIndirectDiffuse == RAY_TRACED_INDIRECT_DIFFUSE_FLAG)
-    {
-        // Incase we shall be using raytraced indirect diffuse, we want to make sure to not add the other forms of indirect lighting to avoid
-        // double contribution.
-        builtinData.bakeDiffuseLighting = float3(0.0, 0.0, 0.0);
-    }
-#endif
 
 #ifdef SHADOWS_SHADOWMASK
     float4 shadowMask = SampleShadowMask(posInput.positionWS, texCoord1.xy);

com.unity.render-pipelines.high-definition/Runtime/Material/SubsurfaceScattering/SubsurfaceScatteringManager.cs

@@ -390,7 +390,7 @@ void RenderSubsurfaceScattering(HDCamera hdCamera, CommandBuffer cmd, RTHandle c
 
                     // Now based on the mask, we need to blend the subsurface and the diffuse lighting
 
-                    bool validSSGI = ValidIndirectDiffuseState(hdCamera);
+                    bool validSSGI = GetIndirectDiffuseMode(hdCamera) != IndirectDiffuseMode.Off;
                     int m_CombineSubSurfaceKernel = rayTracingSubSurfaceCS.FindKernel(validSSGI ? "BlendSubSurfaceDataWithGI" : "BlendSubSurfaceData");
                     cmd.SetComputeTextureParam(rayTracingSubSurfaceCS, m_CombineSubSurfaceKernel, HDShaderIDs._SubSurfaceLightingBuffer, intermediateBuffer0);
                     cmd.SetComputeTextureParam(rayTracingSubSurfaceCS, m_CombineSubSurfaceKernel, HDShaderIDs._DiffuseLightingTextureRW, diffuseBufferRT);

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

@@ -102,6 +102,7 @@ void ExecuteWithRenderGraph(    RenderRequest           renderRequest,
                 //        lightCluster.EvaluateClusterDebugView(cmd, hdCamera);
                 //    }
 
+                // TODO: check code, everything have change
                 //    bool validIndirectDiffuse = ValidIndirectDiffuseState(hdCamera);
                 //    if (validIndirectDiffuse)
                 //    {

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

@@ -1266,21 +1266,21 @@ void UpdateShaderVariablesGlobalCB(HDCamera hdCamera, CommandBuffer cmd)
             m_ShaderVariablesGlobalCB._CoarseStencilBufferSize = new Vector4(coarseStencilWidth, coarseStencilHeight, 1.0f / coarseStencilWidth, 1.0f / coarseStencilHeight);
 
             m_ShaderVariablesGlobalCB._RaytracingFrameIndex = RayTracingFrameIndex(hdCamera);
+            m_ShaderVariablesGlobalCB._IndirectDiffuseMode = (int)GetIndirectDiffuseMode(hdCamera);
+
             if (hdCamera.frameSettings.IsEnabled(FrameSettingsField.RayTracing))
             {
                 // Check if recursive rendering is enabled or not. This will control the cull of primitive
                 // during the gbuffer and forward pass
-                RecursiveRendering recursiveSettings = hdCamera.volumeStack.GetComponent<RecursiveRendering>();
                 ScreenSpaceReflection settings = hdCamera.volumeStack.GetComponent<ScreenSpaceReflection>();
-                bool usesRaytracedReflections = hdCamera.frameSettings.IsEnabled(FrameSettingsField.RayTracing) && settings.rayTracing.value;
-                m_ShaderVariablesGlobalCB._UseRayTracedReflections = usesRaytracedReflections ? 1 : 0;
-                m_ShaderVariablesGlobalCB._UseIndirectDiffuse = ValidIndirectDiffuseState(hdCamera) ? (RayTracedIndirectDiffuseState(hdCamera) ? LightDefinitions.k_RayTracedIndirectDiffuseFlag : LightDefinitions.k_ScreenSpaceIndirectDiffuseFlag) : LightDefinitions.k_IndirectDiffuseFlagOff;
+                bool enableRaytracedReflections = hdCamera.frameSettings.IsEnabled(FrameSettingsField.RayTracing) && settings.rayTracing.value;
+                m_ShaderVariablesGlobalCB._EnableRayTracedReflections = enableRaytracedReflections ? 1 : 0;
+                RecursiveRendering recursiveSettings = hdCamera.volumeStack.GetComponent<RecursiveRendering>();
                 m_ShaderVariablesGlobalCB._EnableRecursiveRayTracing = recursiveSettings.enable.value ? 1u : 0u;
             }
             else
             {
-                m_ShaderVariablesGlobalCB._UseRayTracedReflections = 0;
-                m_ShaderVariablesGlobalCB._UseIndirectDiffuse = ValidIndirectDiffuseState(hdCamera) ? LightDefinitions.k_ScreenSpaceIndirectDiffuseFlag : LightDefinitions.k_IndirectDiffuseFlagOff;
+                m_ShaderVariablesGlobalCB._EnableRayTracedReflections = 0;
                 m_ShaderVariablesGlobalCB._EnableRecursiveRayTracing = 0;
             }
 
@@ -2603,37 +2603,22 @@ void AsyncSSAODispatch(CommandBuffer c, HDGPUAsyncTaskParams a)
                         HDRaytracingLightCluster lightCluster = RequestLightCluster();
                         lightCluster.EvaluateClusterDebugView(cmd, hdCamera);
                     }
-
-                    bool validIndirectDiffuse = ValidIndirectDiffuseState(hdCamera);
-                    if (validIndirectDiffuse)
-                    {
-                        if (RayTracedIndirectDiffuseState(hdCamera))
-                        {
-                            RenderRayTracedIndirectDiffuse(hdCamera, cmd, renderContext, m_FrameCount);
-                        }
-                        else
-                        {
-                            RenderSSGI(hdCamera, cmd, renderContext, m_FrameCount);
-                            BindIndirectDiffuseTexture(cmd);
-                        }
-                    }
-                    else
-                    {
-                        BindBlackIndirectDiffuseTexture(cmd);
-                    }
                 }
-                else
+
+                switch (GetIndirectDiffuseMode(hdCamera))
                 {
-                    bool validIndirectDiffuse = ValidIndirectDiffuseState(hdCamera);
-                    if (validIndirectDiffuse)
-                    {
+                    case IndirectDiffuseMode.Off:
+                        BindBlackIndirectDiffuseTexture(cmd);
+                        break;
+
+                    case IndirectDiffuseMode.ScreenSpace:
                         RenderSSGI(hdCamera, cmd, renderContext, m_FrameCount);
                         BindIndirectDiffuseTexture(cmd);
-                    }
-                    else
-                    {
-                        BindBlackIndirectDiffuseTexture(cmd);
-                    }
+                        break;
+
+                    case IndirectDiffuseMode.Raytrace:
+                        RenderRayTracedIndirectDiffuse(hdCamera, cmd, renderContext, m_FrameCount);
+                        break;
                 }
 
                 if (!hdCamera.frameSettings.SSRRunsAsync())
@@ -5308,7 +5293,16 @@ void SendGeometryGraphicsBuffers(CommandBuffer cmd, HDCamera hdCamera)
             VFXCameraBufferTypes neededVFXBuffers = VFXManager.IsCameraBufferNeeded(hdCamera.camera);
             needNormalBuffer |= ((neededVFXBuffers & VFXCameraBufferTypes.Normal) != 0 || (externalAccess & HDAdditionalCameraData.BufferAccessType.Normal) != 0);
             needDepthBuffer |= ((neededVFXBuffers & VFXCameraBufferTypes.Depth) != 0 || (externalAccess & HDAdditionalCameraData.BufferAccessType.Depth) != 0);
-            if (hdCamera.frameSettings.IsEnabled(FrameSettingsField.RayTracing) && GetRayTracingState() || ValidIndirectDiffuseState(hdCamera))
+            IndirectDiffuseMode indirectDiffuseMode = GetIndirectDiffuseMode(hdCamera);
+
+            // SSGI required the depth of the previous frame
+            if (indirectDiffuseMode == IndirectDiffuseMode.ScreenSpace)
+            {
+                needDepthBuffer = true;
+            }
+
+            // Raytracing require both normal and depth from previous frame.
+            if (hdCamera.frameSettings.IsEnabled(FrameSettingsField.RayTracing) && GetRayTracingState())
             {
                 needNormalBuffer = true;
                 needDepthBuffer = true;