Add gaussian splat asset caching groundwork

engine/include/XCEngine/Core/Asset/AssetDatabase.h

@@ -112,6 +112,10 @@ public:
 
 private:
     static constexpr Core::uint32 kBaseImporterVersion = 7;
+    enum class SourceHashPolicy : Core::uint8 {
+        PreserveOrClear = 0,
+        EnsureCurrent = 1
+    };
 
     void EnsureProjectLayout();
     void LoadSourceAssetDB();
@@ -126,6 +130,7 @@ private:
 
     bool EnsureMetaForPath(const std::filesystem::path& sourcePath,
                            bool isFolder,
+                           SourceHashPolicy sourceHashPolicy,
                            SourceAssetRecord& outRecord);
     bool ReadMetaFile(const std::filesystem::path& metaPath,
                       SourceAssetRecord& inOutRecord) const;

engine/include/XCEngine/Rendering/Passes/BuiltinGaussianSplatPass.h

@@ -70,6 +70,16 @@ private:
         RHI::RHIDescriptorSet* set = nullptr;
     };
 
+    struct CompositePipelineResources {
+        RHI::RHIPipelineLayout* pipelineLayout = nullptr;
+        RHI::RHIPipelineState* pipelineState = nullptr;
+        OwnedDescriptorSet textureSet = {};
+        RHI::RHIResourceView* boundAccumulationView = nullptr;
+        RHI::Format renderTargetFormat = RHI::Format::Unknown;
+        Core::uint32 sampleCount = 1u;
+        Core::uint32 sampleQuality = 0u;
+    };
+
     struct PassLayoutKey {
         const Resources::Shader* shader = nullptr;
         Containers::String passName;
@@ -285,10 +295,21 @@ private:
         const RenderSurface& surface,
         const RenderSceneData& sceneData,
         const VisibleGaussianSplatItem& visibleGaussianSplat);
+    bool EnsureCompositeResources(
+        const RenderContext& context,
+        const RenderSurface& surface);
+    bool CreateCompositeResources(
+        const RenderContext& context,
+        const RenderSurface& surface);
+    void DestroyCompositeResources();
+    bool CompositeAccumulationSurface(
+        const RenderPassContext& context,
+        RHI::RHIResourceView* accumulationTextureView);
 
     RHI::RHIDevice* m_device = nullptr;
     RHI::RHIType m_backendType = RHI::RHIType::D3D12;
     Resources::ResourceHandle<Resources::Shader> m_builtinGaussianSplatShader;
+    Resources::ResourceHandle<Resources::Shader> m_builtinGaussianSplatCompositeShader;
     Resources::ResourceHandle<Resources::Shader> m_builtinGaussianSplatUtilitiesShader;
     std::unique_ptr<Resources::Material> m_builtinGaussianSplatMaterial;
     RenderResourceCache m_resourceCache;
@@ -298,6 +319,7 @@ private:
     std::unordered_map<PipelineStateKey, RHI::RHIPipelineState*, PipelineStateKeyHash> m_pipelineStates;
     std::unordered_map<ComputePipelineKey, RHI::RHIPipelineState*, ComputePipelineKeyHash> m_computePipelineStates;
     std::unordered_map<DynamicDescriptorSetKey, CachedDescriptorSet, DynamicDescriptorSetKeyHash> m_dynamicDescriptorSets;
+    CompositePipelineResources m_compositeResources = {};
 };
 
 } // namespace Passes

engine/include/XCEngine/Resources/BuiltinResources.h

@@ -39,6 +39,7 @@ Containers::String GetBuiltinSelectionMaskShaderPath();
 Containers::String GetBuiltinSelectionOutlineShaderPath();
 Containers::String GetBuiltinSkyboxShaderPath();
 Containers::String GetBuiltinGaussianSplatShaderPath();
+Containers::String GetBuiltinGaussianSplatCompositeShaderPath();
 Containers::String GetBuiltinGaussianSplatUtilitiesShaderPath();
 Containers::String GetBuiltinVolumetricShaderPath();
 Containers::String GetBuiltinColorScalePostProcessShaderPath();