Complete sdf reflections

Content/Editor/MaterialTemplates/Features/ForwardShading.hlsl

@@ -9,10 +9,6 @@
 #define MATERIAL_REFLECTIONS_SSR 1
 #if MATERIAL_REFLECTIONS == MATERIAL_REFLECTIONS_SSR
 #include "./Flax/SSR.hlsl"
-#if USE_GLOBAL_SURFACE_ATLAS
-#include "./Flax/GlobalSignDistanceField.hlsl"
-#include "./Flax/GI/GlobalSurfaceAtlas.hlsl"
-#endif
 #endif
 #endif
 #include "./Flax/Lighting.hlsl"
@@ -31,15 +27,6 @@ LightData LocalLights[MAX_LOCAL_LIGHTS];
 TextureCube EnvProbe : register(t__SRV__);
 TextureCube SkyLightTexture : register(t__SRV__);
 Texture2DArray DirectionalLightShadowMap : register(t__SRV__);
-#if USE_GLOBAL_SURFACE_ATLAS
-Texture3D<float> GlobalSDFTex : register(t__SRV__);
-Texture3D<float> GlobalSDFMip : register(t__SRV__);
-ByteAddressBuffer GlobalSurfaceAtlasChunks : register(t__SRV__);
-ByteAddressBuffer RWGlobalSurfaceAtlasCulledObjects : register(t__SRV__);
-Buffer<float4> GlobalSurfaceAtlasObjects : register(t__SRV__);
-Texture2D GlobalSurfaceAtlasDepth : register(t__SRV__);
-Texture2D GlobalSurfaceAtlasTex : register(t__SRV__);
-#endif
 @4// Forward Shading: Utilities
 DECLARE_LIGHTSHADOWDATA_ACCESS(DirectionalLightShadow);
 @5// Forward Shading: Shaders
@@ -82,7 +69,7 @@ void PS_Forward(
 	gBuffer.Color = material.Color;
 	gBuffer.Specular = material.Specular;
 	gBuffer.AO = material.AO;
-	gBuffer.ViewPos = mul(float4(materialInput.WorldPosition, 1), ViewMatrix).xyz;
+	gBuffer.ViewPos = ViewPos;
 #if MATERIAL_SHADING_MODEL == SHADING_MODEL_SUBSURFACE
 	gBuffer.CustomData = float4(material.SubsurfaceColor, material.Opacity);
 #elif MATERIAL_SHADING_MODEL == SHADING_MODEL_FOLIAGE
@@ -148,21 +135,12 @@ void PS_Forward(
 	if (hit.z < 0.9f)
 	{
 		// Don't use temporal effect in forward pass
-		float3 reflectWS = ScreenSpaceReflectionDirection(screenUV, gBuffer, gBufferData.ViewPos);
+		float3 reflectWS = ScreenSpaceReflectionDirection(screenUV, gBuffer, ViewPos);
-
+		float4 surfaceAtlas;
-		GlobalSDFTrace sdfTrace;
-		float maxDistance = 100000;
-		float selfOcclusionBias = GlobalSDF.CascadeVoxelSize[0];
-		sdfTrace.Init(gBuffer.WorldPos + gBuffer.Normal * selfOcclusionBias, reflectWS, 0.0f, maxDistance);
-		GlobalSDFHit sdfHit = RayTraceGlobalSDF(GlobalSDF, GlobalSDFTex, GlobalSDFMip, sdfTrace);
-		if (sdfHit.IsHit())
-		{
-			float3 hitPosition = sdfHit.GetHitPosition(sdfTrace);
-			float surfaceThreshold = GetGlobalSurfaceAtlasThreshold(GlobalSDF, sdfHit);
-			float4 surfaceAtlas = SampleGlobalSurfaceAtlas(GlobalSurfaceAtlas, GlobalSurfaceAtlasChunks, RWGlobalSurfaceAtlasCulledObjects, GlobalSurfaceAtlasObjects, GlobalSurfaceAtlasDepth, GlobalSurfaceAtlasTex, hitPosition, -reflectWS, surfaceThreshold);
 
+		if(TraceSDFSoftwareReflections(gBuffer, reflectWS, surfaceAtlas)){
 			float3 screenColor = sceneColorTexture.SampleLevel(SamplerPointClamp, hit.xy, 0).rgb;
-			reflections = lerp(surfaceAtlas, float4(screenColor, 1), hit.z);
+        	reflections = lerp(2 * surfaceAtlas, float4(screenColor, 1), hit.z);
 		}
 	}
 
@@ -174,6 +152,7 @@ void PS_Forward(
 
 	// Add lighting (apply ambient occlusion)
 	output.rgb += light.rgb * gBuffer.AO;
+	output = 
 
 #endif
 

Content/Editor/MaterialTemplates/Features/SDFReflections.hlsl

@@ -0,0 +1,39 @@
+// Copyright (c) 2012-2024 Wojciech Figat. All rights reserved.
+
+@0// SDF Reflections: Defines
+#define USE_GLOBAL_SURFACE_ATLAS 1
+@1// SDF Reflections: Includes
+#include "./Flax/GlobalSignDistanceField.hlsl"
+#include "./Flax/GI/GlobalSurfaceAtlas.hlsl"
+@2// SDF Reflections: Constants
+GlobalSDFData GlobalSDF;
+GlobalSurfaceAtlasData GlobalSurfaceAtlas;
+@3// SDF Reflections: Resources
+Texture3D<float> GlobalSDFTex : register(t__SRV__);
+Texture3D<float> GlobalSDFMip : register(t__SRV__);
+ByteAddressBuffer GlobalSurfaceAtlasChunks : register(t__SRV__);
+ByteAddressBuffer RWGlobalSurfaceAtlasCulledObjects : register(t__SRV__);
+Buffer<float4> GlobalSurfaceAtlasObjects : register(t__SRV__);
+Texture2D GlobalSurfaceAtlasDepth : register(t__SRV__);
+Texture2D GlobalSurfaceAtlasTex : register(t__SRV__);
+@4// SDF Reflections: Utilities
+bool TraceSDFSoftwareReflections(GBufferSample gBuffer, float3 reflectWS, out float4 surfaceAtlas)
+{
+	GlobalSDFTrace sdfTrace;
+    float maxDistance = 100000;
+    float selfOcclusionBias = GlobalSDF.CascadeVoxelSize[0];
+    sdfTrace.Init(gBuffer.WorldPos + gBuffer.Normal * selfOcclusionBias, reflectWS, 0.0f, maxDistance);
+    GlobalSDFHit sdfHit = RayTraceGlobalSDF(GlobalSDF, GlobalSDFTex, GlobalSDFMip, sdfTrace);
+    if (sdfHit.IsHit())
+    {
+        float3 hitPosition = sdfHit.GetHitPosition(sdfTrace);
+        float surfaceThreshold = GetGlobalSurfaceAtlasThreshold(GlobalSDF, sdfHit);
+        surfaceAtlas = SampleGlobalSurfaceAtlas(GlobalSurfaceAtlas, GlobalSurfaceAtlasChunks, RWGlobalSurfaceAtlasCulledObjects, GlobalSurfaceAtlasObjects, GlobalSurfaceAtlasDepth, GlobalSurfaceAtlasTex, hitPosition, -reflectWS, surfaceThreshold);
+        
+        return true;
+    }
+
+    return false;
+}
+
+@5// SDF Reflections: Shaders

Source/Engine/Graphics/Materials/ForwardMaterialShader.cpp

@@ -53,6 +53,8 @@ void ForwardMaterialShader::Bind(BindParameters& params)
     // Setup features
     if ((_info.FeaturesFlags & MaterialFeaturesFlags::GlobalIllumination) != MaterialFeaturesFlags::None)
         GlobalIlluminationFeature::Bind(params, cb, srv);
+    if ((_info.FeaturesFlags & MaterialFeaturesFlags::ScreenSpaceReflections) != MaterialFeaturesFlags::None)
+        SDFReflectionsFeature::Bind(params, cb, srv);
     ForwardShadingFeature::Bind(params, cb, srv);
 
     // Setup parameters

Source/Engine/Graphics/Materials/MaterialShaderFeatures.cpp

@@ -100,15 +100,6 @@ void ForwardShadingFeature::Bind(MaterialShader::BindParameters& params, Span<by
         params.GPUContext->UnBindSR(envProbeShaderRegisterIndex);
     }
 
-    // Bind sdf resources if using software reflections
-    if (!GlobalSignDistanceFieldPass::Instance()->Render(params.RenderContext, params.GPUContext, bindingDataSDF) &&
-        !GlobalSurfaceAtlasPass::Instance()->Render(params.RenderContext, params.GPUContext, bindingDataSurfaceAtlas))
-    {
-        useGlobalSurfaceAtlas = true;
-        data.GlobalSDF = bindingDataSDF.Constants;
-        data.GlobalSurfaceAtlas = bindingDataSurfaceAtlas.Constants;
-    }
-
     // Set local lights
     data.LocalLightsCount = 0;
     const BoundingSphere objectBounds(drawCall.ObjectPosition, drawCall.ObjectRadius);
@@ -143,13 +134,13 @@ bool LightmapFeature::Bind(MaterialShader::BindParameters& params, Span<byte>& c
 
     const bool useLightmap = EnumHasAnyFlags(params.RenderContext.View.Flags, ViewFlags::GI)
 #if USE_EDITOR
-            && EnableLightmapsUsage
+        && EnableLightmapsUsage
 #endif
-            && drawCall.Surface.Lightmap != nullptr;
+        && drawCall.Surface.Lightmap != nullptr;
     if (useLightmap)
     {
         // Bind lightmap textures
-        GPUTexture *lightmap0, *lightmap1, *lightmap2;
+        GPUTexture* lightmap0, * lightmap1, * lightmap2;
         drawCall.Features.Lightmap->GetTextures(&lightmap0, &lightmap1, &lightmap2);
         params.GPUContext->BindSR(srv + 0, lightmap0);
         params.GPUContext->BindSR(srv + 1, lightmap1);
@@ -207,6 +198,61 @@ bool GlobalIlluminationFeature::Bind(MaterialShader::BindParameters& params, Spa
     return useGI;
 }
 
+bool SDFReflectionsFeature::Bind(MaterialShader::BindParameters& params, Span<byte>& cb, int32& srv)
+{
+    auto& data = *(Data*)cb.Get();
+    ASSERT_LOW_LAYER(cb.Length() >= sizeof(Data));
+
+    bool useSDFReflections = false;
+    if (EnumHasAnyFlags(params.RenderContext.View.Flags, ViewFlags::Reflections))
+    {
+        switch (params.RenderContext.List->Settings.ScreenSpaceReflections.TraceMode)
+        {
+        case ReflectionsTraceMode::SoftwareTracing:
+        {
+            GlobalSignDistanceFieldPass::BindingData bindingDataSDF;
+            GlobalSurfaceAtlasPass::BindingData bindingDataSurfaceAtlas;
+
+            if (!GlobalSignDistanceFieldPass::Instance()->Get(params.RenderContext.Buffers, bindingDataSDF) &&
+                !GlobalSurfaceAtlasPass::Instance()->Get(params.RenderContext.Buffers, bindingDataSurfaceAtlas))
+            {
+                useSDFReflections = true;
+
+                // Bind DDGI data
+                data.GlobalSDF = bindingDataSDF.Constants;
+                data.GlobalSurfaceAtlas = bindingDataSurfaceAtlas.Constants;
+
+                params.GPUContext->BindSR(srv + 0, bindingDataSDF.Texture ? bindingDataSDF.Texture->ViewVolume() : nullptr);
+                params.GPUContext->BindSR(srv + 1, bindingDataSDF.TextureMip ? bindingDataSDF.TextureMip->ViewVolume() : nullptr);
+                params.GPUContext->BindSR(srv + 2, bindingDataSurfaceAtlas.Chunks ? bindingDataSurfaceAtlas.Chunks->View() : nullptr);
+                params.GPUContext->BindSR(srv + 3, bindingDataSurfaceAtlas.CulledObjects ? bindingDataSurfaceAtlas.CulledObjects->View() : nullptr);
+                params.GPUContext->BindSR(srv + 4, bindingDataSurfaceAtlas.Objects ? bindingDataSurfaceAtlas.Objects->View() : nullptr);
+                params.GPUContext->BindSR(srv + 5, bindingDataSurfaceAtlas.AtlasDepth->View());
+                params.GPUContext->BindSR(srv + 6, bindingDataSurfaceAtlas.AtlasLighting->View());
+            }
+            break;
+        }
+        }
+    }
+
+    if (!useSDFReflections)
+    {
+        data.GlobalSDF.CascadesCount = 0;
+        // Unbind SRVs to prevent issues
+        params.GPUContext->UnBindSR(srv + 0);
+        params.GPUContext->UnBindSR(srv + 1);
+        params.GPUContext->UnBindSR(srv + 2);
+        params.GPUContext->UnBindSR(srv + 3);
+        params.GPUContext->UnBindSR(srv + 4);
+        params.GPUContext->UnBindSR(srv + 5);
+        params.GPUContext->UnBindSR(srv + 6);
+    }
+
+    cb = Span<byte>(cb.Get() + sizeof(Data), cb.Length() - sizeof(Data));
+    srv += SRVs;
+    return useSDFReflections;
+}
+
 #if USE_EDITOR
 
 void ForwardShadingFeature::Generate(GeneratorData& data)
@@ -234,6 +280,11 @@ void GlobalIlluminationFeature::Generate(GeneratorData& data)
     data.Template = TEXT("Features/GlobalIllumination.hlsl");
 }
 
+void SDFReflectionsFeature::Generate(GeneratorData& data)
+{
+    data.Template = TEXT("Features/SDFReflections.hlsl");
+}
+
 void DistortionFeature::Generate(GeneratorData& data)
 {
     data.Template = TEXT("Features/Distortion.hlsl");

Source/Engine/Graphics/Materials/MaterialShaderFeatures.h

@@ -6,6 +6,8 @@
 #include "Engine/Core/Math/Rectangle.h"
 #include "Engine/Core/Types/Span.h"
 #include "Engine/Renderer/GI/DynamicDiffuseGlobalIllumination.h"
+#include "Engine/Renderer/GlobalSignDistanceFieldPass.h"
+#include "Engine/Renderer/GI/GlobalSurfaceAtlasPass.h"
 
 // Material shader features are plugin-based functionalities that are reusable between different material domains.
 struct MaterialShaderFeature
@@ -91,6 +93,25 @@ struct GlobalIlluminationFeature : MaterialShaderFeature
 #endif
 };
 
+// Material shader feature that adds SDF Reflections feature (software reflections). 
+struct SDFReflectionsFeature : MaterialShaderFeature
+{
+    enum { SRVs = 7 };
+
+    PACK_STRUCT(struct Data
+    {
+        GlobalSignDistanceFieldPass::ConstantsData GlobalSDF;
+        GlobalSurfaceAtlasPass::ConstantsData GlobalSurfaceAtlas;
+    });
+
+    
+
+    static bool Bind(MaterialShader::BindParameters& params, Span<byte>& cb, int32& srv);
+#if USE_EDITOR
+    static void Generate(GeneratorData& data);
+#endif
+};
+
 // Material shader feature that adds distortion vectors rendering pass.
 struct DistortionFeature : MaterialShaderFeature
 {

Source/Engine/Renderer/GI/GlobalSurfaceAtlasPass.cpp

@@ -360,6 +360,17 @@ void GlobalSurfaceAtlasPass::Dispose()
     _shader = nullptr;
 }
 
+bool GlobalSurfaceAtlasPass::Get(const RenderBuffers* buffers, BindingData& result)
+{
+    auto* surfaceAtlasData = buffers ? buffers->FindCustomBuffer<GlobalSurfaceAtlasCustomBuffer>(TEXT("GlobalSurfaceAtlas")) : nullptr;
+    if (surfaceAtlasData && surfaceAtlasData->LastFrameUsed + 1 >= Engine::FrameCount) // Allow to use Surface Atlas from the previous frame (not used currently)
+    {
+        result = surfaceAtlasData->Result;
+        return false;
+    }
+    return true;
+}
+
 bool GlobalSurfaceAtlasPass::Render(RenderContext& renderContext, GPUContext* context, BindingData& result)
 {
     // Skip if not supported

Source/Engine/Renderer/GI/GlobalSurfaceAtlasPass.h

@@ -65,6 +65,14 @@ private:
     void* _currentActorObject;
 
 public:
+    /// <summary>
+    /// Gets the Global Surface Atlas (only if enabled in Graphics Settings).
+    /// </summary>
+    /// <param name="buffers">The rendering context buffers.</param>
+    /// <param name="result">The result Global Surface Atlas data for binding to the shaders.</param>
+    /// <returns>True if there is no valid Global Surface Atlas rendered during this frame, otherwise false.</returns>
+    bool Get(const RenderBuffers* buffers, BindingData& result);
+
     /// <summary>
     /// Renders the Global Surface Atlas.
     /// </summary>

Source/Engine/Tools/MaterialGenerator/MaterialGenerator.cpp

@@ -199,6 +199,8 @@ bool MaterialGenerator::Generate(WriteStream& source, MaterialInfo& materialInfo
         ADD_FEATURE(DistortionFeature);
         if (materialInfo.BlendMode != MaterialBlendMode::Opaque && EnumHasAnyFlags(materialInfo.FeaturesFlags, MaterialFeaturesFlags::GlobalIllumination))
         ADD_FEATURE(GlobalIlluminationFeature);
+        if (materialInfo.BlendMode != MaterialBlendMode::Opaque && EnumHasAnyFlags(materialInfo.FeaturesFlags, MaterialFeaturesFlags::ScreenSpaceReflections))
+        ADD_FEATURE(SDFReflectionsFeature);
         if (materialInfo.BlendMode != MaterialBlendMode::Opaque)
         ADD_FEATURE(ForwardShadingFeature);
         break;

Source/Shaders/SSR.shader

@@ -150,8 +150,8 @@ float4 PS_RayTracePass(Quad_VS2PS input) : SV_Target0
         float surfaceThreshold = GetGlobalSurfaceAtlasThreshold(GlobalSDF, sdfHit);
         float4 surfaceAtlas = SampleGlobalSurfaceAtlas(GlobalSurfaceAtlas, GlobalSurfaceAtlasChunks, RWGlobalSurfaceAtlasCulledObjects, GlobalSurfaceAtlasObjects, GlobalSurfaceAtlasDepth, GlobalSurfaceAtlasTex, hitPosition, -reflectWS, surfaceThreshold);
         // Now the sdf reflection part is significantly darker than the screen space part
-		// TODO: Maybe multiply surfaceAtlas by a constant to make it brighter
+		// TODO: Maybe multiply surfaceAtlas by a constant to make it brighter, adding 2* looks fine
-		result = lerp(surfaceAtlas, float4(result.rgb, 1), result.a);
+		result = lerp(2 * surfaceAtlas, float4(result.rgb, 1), result.a);
     }
 #endif