Merge pull request #55 from Unity-Technologies/HackShadowPCF

Hacked in a better PCF for directional light.

Assets/ScriptableRenderLoop/HDRenderLoop/HDRenderLoop.cs

 
 
         // Function to prepare light structure for GPU lighting
-        void PrepareLightsForGPU(CullResults cullResults, Camera camera, ref ShadowOutput shadowOutput)
+        void PrepareLightsForGPU(ShadowSettings shadowSettings, CullResults cullResults, Camera camera, ref ShadowOutput shadowOutput)
-            m_lightLoop.PrepareLightsForGPU(cullResults, camera, ref shadowOutput);
+            m_lightLoop.PrepareLightsForGPU(shadowSettings, cullResults, camera, ref shadowOutput);
         }
 
         void Resize(Camera camera)
 
                     using (new Utilities.ProfilingSample("Build Light list", renderLoop))
                     {
-                        m_lightLoop.PrepareLightsForGPU(cullResults, camera, ref shadows);
+                        m_lightLoop.PrepareLightsForGPU(m_ShadowSettings, cullResults, camera, ref shadows);
                         m_lightLoop.BuildGPULightLists(camera, renderLoop, m_CameraDepthBufferRT);
 
                         PushGlobalParams(hdCamera, renderLoop);

Assets/ScriptableRenderLoop/HDRenderLoop/Lighting/LightDefinition.cs

         public float bias;
         public float quality;
         public float unused;
+        public Vector4 invResolution;
     };
 
     [GenerateHLSL]

Assets/ScriptableRenderLoop/HDRenderLoop/Lighting/LightDefinition.cs.hlsl

 	float bias;
 	float quality;
 	float unused;
+	float4 invResolution;
 };
 
 // Generated from UnityEngine.Experimental.ScriptableRenderLoop.EnvLightData
 float GetUnused(ShadowData value)
 {
 	return value.unused;
+}
+float4 GetInvResolution(ShadowData value)
+{
+	return value.invResolution;
 }
 
 //

Assets/ScriptableRenderLoop/HDRenderLoop/Lighting/LightLoop.cs

 
         public virtual void NewFrame() {}
 
-        public virtual void PrepareLightsForGPU(CullResults cullResults, Camera camera, ref ShadowOutput shadowOutput) { }
+        public virtual void PrepareLightsForGPU(ShadowSettings shadowSettings, CullResults cullResults, Camera camera, ref ShadowOutput shadowOutput) { }
         
         // TODO: this should not be part of the interface but for now make something working
         public virtual void BuildGPULightLists(Camera camera, RenderLoop loop, RenderTargetIdentifier cameraDepthBufferRT) { }

Assets/ScriptableRenderLoop/HDRenderLoop/Lighting/TilePass/TilePass.cs

             }
 
             // Return number of added shadow
-            public int GetShadows(VisibleLight light, int lightIndex, ref ShadowOutput shadowOutput)
+            public int GetShadows(VisibleLight light, int lightIndex, ref ShadowOutput shadowOutput, ShadowSettings shadowSettings)
             {
                 for (int sliceIndex = 0; sliceIndex < shadowOutput.GetShadowSliceCountLightIndex(lightIndex); ++sliceIndex)
                 {
                     shadowData.worldToShadow = shadowOutput.shadowSlices[shadowSliceIndex].shadowTransform.transpose; // Transpose for hlsl reading ?
 
                     shadowData.bias = light.light.shadowBias;
-
+                    shadowData.invResolution = new Vector4(1.0f / shadowSettings.shadowAtlasWidth, 1.0f / shadowSettings.shadowAtlasHeight, 0.0f, 0.0f);
                     m_lightList.shadows.Add(shadowData);
                 }
 
-            public void GetDirectionalLightData(GPULightType gpuLightType, VisibleLight light, AdditionalLightData additionalData, int lightIndex, ref ShadowOutput shadowOutput, ref int directionalShadowcount)
+            public void GetDirectionalLightData(ShadowSettings shadowSettings, GPULightType gpuLightType, VisibleLight light, AdditionalLightData additionalData, int lightIndex, ref ShadowOutput shadowOutput, ref int directionalShadowcount)
             {
                 var directionalLightData = new DirectionalLightData();
 
                     m_CurrentSunLight = light.light;
 
                     directionalLightData.shadowIndex = m_lightList.shadows.Count;
-                    directionalShadowcount += GetShadows(light, lightIndex, ref shadowOutput);
+                    directionalShadowcount += GetShadows(light, lightIndex, ref shadowOutput, shadowSettings);
 
                     // Fill split information for shaders
                     for (int s = 0; s < k_MaxCascadeCount; ++s)
                 m_lightList.directionalLights.Add(directionalLightData);
             }
 
-            public void GetLightData(GPULightType gpuLightType, VisibleLight light, AdditionalLightData additionalData, int lightIndex, ref ShadowOutput shadowOutput, ref int shadowCount)
+            public void GetLightData(ShadowSettings shadowSettings, GPULightType gpuLightType, VisibleLight light, AdditionalLightData additionalData, int lightIndex, ref ShadowOutput shadowOutput, ref int shadowCount)
             {
                 var lightData = new LightData();
 
                 {
                     // When we have a point light, we assumed that there is 6 consecutive PunctualShadowData
                     lightData.shadowIndex = m_lightList.shadows.Count;
-                    shadowCount += GetShadows(light, lightIndex, ref shadowOutput);
+                    shadowCount += GetShadows(light, lightIndex, ref shadowOutput, shadowSettings);
                 }
 
                 if (additionalData.archetype != LightArchetype.Punctual)
                 m_lightList.lightVolumes.Add(ligthVolumeData);
             }
 
-            public override void PrepareLightsForGPU(CullResults cullResults, Camera camera, ref ShadowOutput shadowOutput)
+            public override void PrepareLightsForGPU(ShadowSettings shadowSettings, CullResults cullResults, Camera camera, ref ShadowOutput shadowOutput)
             {
                 m_lightList.Clear();
 
                     // Directional rendering side, it is separated as it is always visible so no volume to handle here
                     if (gpuLightType == GPULightType.Directional)
                     {
-                        GetDirectionalLightData(gpuLightType, light, additionalData, lightIndex, ref shadowOutput, ref directionalShadowcount);
+                        GetDirectionalLightData(shadowSettings, gpuLightType, light, additionalData, lightIndex, ref shadowOutput, ref directionalShadowcount);
-                    GetLightData(gpuLightType, light, additionalData, lightIndex, ref shadowOutput, ref shadowCount);
+                    GetLightData(shadowSettings, gpuLightType, light, additionalData, lightIndex, ref shadowOutput, ref shadowCount);
                     // Then culling side. Must be call in this order as we pass the created Light data to the function
                     GetLightVolumeDataAndBound(lightCategory, gpuLightType, lightVolumeType, light, m_lightList.lights[m_lightList.lights.Count - 1], worldToView);
                 }

Assets/ScriptableRenderLoop/HDRenderLoop/Lighting/TilePass/TilePass.hlsl

     positionTXS.z = 1.0 - positionTXS.z;
 #endif
 
+    float4 vShadow3x3PCFTerms0;
+    float4 vShadow3x3PCFTerms1;
+    float4 vShadow3x3PCFTerms2;
+    float4 vShadow3x3PCFTerms3;
+
+    float flTexelEpsilonX = shadowData.invResolution.x;
+    float flTexelEpsilonY = shadowData.invResolution.y;
+    vShadow3x3PCFTerms0 = float4(20.0f / 267.0f, 33.0f / 267.0f, 55.0f / 267.0f, 0.0f);
+    vShadow3x3PCFTerms1 = float4(flTexelEpsilonX, flTexelEpsilonY, -flTexelEpsilonX, -flTexelEpsilonY);
+    vShadow3x3PCFTerms2 = float4(flTexelEpsilonX, flTexelEpsilonY, 0.0f, 0.0f);
+    vShadow3x3PCFTerms3 = float4(-flTexelEpsilonX, -flTexelEpsilonY, 0.0f, 0.0f);
+
-    return SAMPLE_TEXTURE2D_SHADOW(g_tShadowBuffer, samplerg_tShadowBuffer, positionTXS);
+    //return SAMPLE_TEXTURE2D_SHADOW(g_tShadowBuffer, samplerg_tShadowBuffer, positionTXS);
+
+    float4 v20Taps;
+    v20Taps.x = SAMPLE_TEXTURE2D_SHADOW(g_tShadowBuffer, samplerg_tShadowBuffer, float3(positionTXS.xy + vShadow3x3PCFTerms1.xy, positionTXS.z)).x; //  1  1
+    v20Taps.y = SAMPLE_TEXTURE2D_SHADOW(g_tShadowBuffer, samplerg_tShadowBuffer, float3(positionTXS.xy + vShadow3x3PCFTerms1.zy, positionTXS.z)).x; // -1  1
+    v20Taps.z = SAMPLE_TEXTURE2D_SHADOW(g_tShadowBuffer, samplerg_tShadowBuffer, float3(positionTXS.xy + vShadow3x3PCFTerms1.xw, positionTXS.z)).x; //  1 -1
+    v20Taps.w = SAMPLE_TEXTURE2D_SHADOW(g_tShadowBuffer, samplerg_tShadowBuffer, float3(positionTXS.xy + vShadow3x3PCFTerms1.zw, positionTXS.z)).x; // -1 -1
+    float flSum = dot(v20Taps.xyzw, float4(0.25, 0.25, 0.25, 0.25));
+    if ((flSum == 0.0) || (flSum == 1.0))
+        return flSum;
+    flSum *= vShadow3x3PCFTerms0.x * 4.0;
+
+    float4 v33Taps;
+    v33Taps.x = SAMPLE_TEXTURE2D_SHADOW(g_tShadowBuffer, samplerg_tShadowBuffer, float3(positionTXS.xy + vShadow3x3PCFTerms2.xz, positionTXS.z)).x; //  1  0
+    v33Taps.y = SAMPLE_TEXTURE2D_SHADOW(g_tShadowBuffer, samplerg_tShadowBuffer, float3(positionTXS.xy + vShadow3x3PCFTerms3.xz, positionTXS.z)).x; // -1  0
+    v33Taps.z = SAMPLE_TEXTURE2D_SHADOW(g_tShadowBuffer, samplerg_tShadowBuffer, float3(positionTXS.xy + vShadow3x3PCFTerms3.zy, positionTXS.z)).x; //  0 -1
+    v33Taps.w = SAMPLE_TEXTURE2D_SHADOW(g_tShadowBuffer, samplerg_tShadowBuffer, float3(positionTXS.xy + vShadow3x3PCFTerms2.zy, positionTXS.z)).x; //  0  1
+    flSum += dot(v33Taps.xyzw, vShadow3x3PCFTerms0.yyyy);
+
+    flSum += SAMPLE_TEXTURE2D_SHADOW(g_tShadowBuffer, samplerg_tShadowBuffer, positionTXS).x * vShadow3x3PCFTerms0.z;
+
+    return flSum;
+
 }
 
 //-----------------------------------------------------------------------------