初始提交: UE5.3项目基础框架

Plugins/CesiumForUnreal/Source/CesiumRuntime/Private/CesiumPointAttenuationVertexFactory.h

@@ -0,0 +1,74 @@
+// Copyright 2020-2024 CesiumGS, Inc. and Contributors
+
+#pragma once
+
+#include "CesiumCommon.h"
+#include "Engine/StaticMesh.h"
+#include "LocalVertexFactory.h"
+#include "RHIDefinitions.h"
+#include "RHIResources.h"
+#include "Rendering/PositionVertexBuffer.h"
+#include "Runtime/Launch/Resources/Version.h"
+#include "SceneManagement.h"
+
+/**
+ * This generates the indices necessary for point attenuation in a
+ * FCesiumGltfPointsComponent.
+ */
+class FCesiumPointAttenuationIndexBuffer : public FIndexBuffer {
+public:
+  FCesiumPointAttenuationIndexBuffer(
+      const int32& NumPoints,
+      const bool bAttenuationSupported)
+      : NumPoints(NumPoints), bAttenuationSupported(bAttenuationSupported) {}
+
+  virtual void InitRHI(FRHICommandListBase& RHICmdList) override;
+
+private:
+  // The number of points in the original point mesh. Not to be confused with
+  // the number of vertices in the attenuated point mesh.
+  const int32 NumPoints;
+  const bool bAttenuationSupported;
+};
+
+/**
+ * The parameters to be passed as UserData to the
+ * shader.
+ */
+struct FCesiumPointAttenuationBatchElementUserData {
+  FRHIShaderResourceView* PositionBuffer;
+  FRHIShaderResourceView* PackedTangentsBuffer;
+  FRHIShaderResourceView* ColorBuffer;
+  FRHIShaderResourceView* TexCoordBuffer;
+  uint32 NumTexCoords;
+  uint32 bHasPointColors;
+  FVector3f AttenuationParameters;
+};
+
+class FCesiumPointAttenuationBatchElementUserDataWrapper
+    : public FOneFrameResource {
+public:
+  FCesiumPointAttenuationBatchElementUserData Data;
+};
+
+class FCesiumPointAttenuationVertexFactory : public FLocalVertexFactory {
+
+  DECLARE_VERTEX_FACTORY_TYPE(FCesiumPointAttenuationVertexFactory);
+
+public:
+  // Sets default values for this component's properties
+  FCesiumPointAttenuationVertexFactory(
+      ERHIFeatureLevel::Type InFeatureLevel,
+      const FPositionVertexBuffer* PositionVertexBuffer);
+
+  static bool ShouldCompilePermutation(
+      const FVertexFactoryShaderPermutationParameters& Parameters);
+
+  static void ModifyCompilationEnvironment(
+      const FVertexFactoryShaderPermutationParameters& Parameters,
+      FShaderCompilerEnvironment& OutEnvironment);
+
+private:
+  virtual void InitRHI(FRHICommandListBase& RHICmdList) override;
+  virtual void ReleaseRHI() override;
+};