初始提交: UE5.3项目基础框架

Plugins/CesiumForUnreal/Source/CesiumRuntime/Public/CesiumPrimitiveFeatures.h

@@ -0,0 +1,196 @@
+// Copyright 2020-2024 CesiumGS, Inc. and Contributors
+
+#pragma once
+
+#include "CesiumFeatureIdSet.h"
+#include "Kismet/BlueprintFunctionLibrary.h"
+#include "UObject/ObjectMacros.h"
+#include <CesiumGltf/AccessorUtility.h>
+
+#include "CesiumPrimitiveFeatures.generated.h"
+
+namespace CesiumGltf {
+struct ExtensionExtMeshFeatures;
+struct ExtensionExtInstanceFeatures;
+} // namespace CesiumGltf
+
+/**
+ * A Blueprint-accessible wrapper for a glTF Primitive's mesh features. It holds
+ * views of the feature ID sets associated with this primitive. The collection
+ * of features in the EXT_instance_features is very similar to that in
+ * EXT_mesh_features, so FCesiumPrimitiveFeatures can be used to handle those
+ * features too.
+ */
+USTRUCT(BlueprintType)
+struct CESIUMRUNTIME_API FCesiumPrimitiveFeatures {
+  GENERATED_USTRUCT_BODY()
+
+public:
+  /**
+   * Constructs an empty primitive features instance.
+   */
+  FCesiumPrimitiveFeatures() : _vertexCount(0) {}
+
+  /**
+   * Constructs a primitive features instance.
+   *
+   * @param Model The model that contains the EXT_mesh_features extension
+   * @param Primitive The mesh primitive that stores EXT_mesh_features
+   * extension
+   * @param Features The EXT_mesh_features of the glTF mesh primitive
+   */
+  FCesiumPrimitiveFeatures(
+      const CesiumGltf::Model& Model,
+      const CesiumGltf::MeshPrimitive& Primitive,
+      const CesiumGltf::ExtensionExtMeshFeatures& Features);
+
+  /**
+   * Constructs an instance feature object.
+   *
+   * @param Model The model that contains the EXT_instance_features extension
+   * @param Node The node that stores EXT_instance_features
+   * extension
+   * @param InstanceFeatures The EXT_Instance_features of the glTF mesh
+   * primitive
+   */
+  FCesiumPrimitiveFeatures(
+      const CesiumGltf::Model& Model,
+      const CesiumGltf::Node& Node,
+      const CesiumGltf::ExtensionExtInstanceFeatures& InstanceFeatures);
+
+private:
+  TArray<FCesiumFeatureIdSet> _featureIdSets;
+  CesiumGltf::IndexAccessorType _indexAccessor;
+  // Vertex count = 0 and _primitiveMode = -1 indicates instance features
+  int64_t _vertexCount;
+  int32_t _primitiveMode;
+
+  friend class UCesiumPrimitiveFeaturesBlueprintLibrary;
+};
+
+UCLASS()
+class CESIUMRUNTIME_API UCesiumPrimitiveFeaturesBlueprintLibrary
+    : public UBlueprintFunctionLibrary {
+  GENERATED_BODY()
+
+public:
+  /**
+   * Gets the primitive features of a glTF primitive component. If `component`
+   * is not a Cesium glTF primitive component, the returned features are empty.
+   *
+   * @param component The component to get the features of.
+   */
+  UFUNCTION(
+      BlueprintCallable,
+      BlueprintPure,
+      Category = "Cesium|Primitive|Features")
+  static const FCesiumPrimitiveFeatures&
+  GetPrimitiveFeatures(const UPrimitiveComponent* component);
+
+  /**
+   * Gets all the feature ID sets that are associated with the
+   * primitive.
+   *
+   * @param PrimitiveFeatures The primitive.
+   */
+  UFUNCTION(
+      BlueprintCallable,
+      BlueprintPure,
+      Category = "Cesium|Primitive|Features")
+  static const TArray<FCesiumFeatureIdSet>&
+  GetFeatureIDSets(UPARAM(ref)
+                       const FCesiumPrimitiveFeatures& PrimitiveFeatures);
+
+  /**
+   * Gets all the feature ID sets of the given type.
+   *
+   * @param PrimitiveFeatures The primitive.
+   * @param Type The type of feature ID set to obtain. If the primitive has no
+   * sets of that type, the returned array will be empty.
+   */
+  UFUNCTION(
+      BlueprintCallable,
+      BlueprintPure,
+      Category = "Cesium|Primitive|Features")
+  static const TArray<FCesiumFeatureIdSet> GetFeatureIDSetsOfType(
+      UPARAM(ref) const FCesiumPrimitiveFeatures& PrimitiveFeatures,
+      ECesiumFeatureIdSetType Type);
+
+  /**
+   * Get the number of vertices in the primitive.
+   *
+   * @param PrimitiveFeatures The primitive.
+   */
+  UFUNCTION(
+      BlueprintCallable,
+      BlueprintPure,
+      Category = "Cesium|Primitive|Features")
+  static int64
+  GetVertexCount(UPARAM(ref) const FCesiumPrimitiveFeatures& PrimitiveFeatures);
+
+  /**
+   * Gets the index of the first vertex that makes up a given face of this
+   * primitive.
+   *
+   * @param PrimitiveFeatures The primitive.
+   * @param FaceIndex The index of the face.
+   */
+  UFUNCTION(
+      BlueprintCallable,
+      BlueprintPure,
+      Category = "Cesium|Primitive|Features")
+  static int64 GetFirstVertexFromFace(
+      UPARAM(ref) const FCesiumPrimitiveFeatures& PrimitiveFeatures,
+      int64 FaceIndex);
+
+  /**
+   * Gets the feature ID associated with the given face.
+   *
+   * @param PrimitiveFeatures The primitive.
+   * @param FaceIndex The index of the face to obtain the feature ID of.
+   * @param FeatureIDSetIndex  A primitive may have multiple feature ID sets, so
+   * this allows a feature ID set to be specified by index. This value should
+   * index into the array of CesiumFeatureIdSets in the CesiumPrimitiveFeatures.
+   * If the specified feature ID set index is invalid, this returns -1.
+   */
+  UFUNCTION(
+      BlueprintCallable,
+      BlueprintPure,
+      Category = "Cesium|Primitive|Features")
+  static int64 GetFeatureIDFromFace(
+      UPARAM(ref) const FCesiumPrimitiveFeatures& PrimitiveFeatures,
+      int64 FaceIndex,
+      int64 FeatureIDSetIndex = 0);
+
+  /**
+   * Gets the feature ID associated with the instance at the given index.
+   */
+  UFUNCTION(
+      BlueprintCallable,
+      BlueprintPure,
+      Category = "Cesium|Primitive|Features")
+  static int64 GetFeatureIDFromInstance(
+      UPARAM(ref) const FCesiumPrimitiveFeatures& InstanceFeatures,
+      int64 InstanceIndex,
+      int64 FeatureIDSetIndex = 0);
+
+  /**
+   * Gets the feature ID from the given line trace hit, assuming it
+   * has hit a glTF primitive component containing this CesiumPrimitiveFeatures.
+   *
+   * @param PrimitiveFeatures The primitive.
+   * @param Hit The line trace hit to try to obtain a feature ID from.
+   * @param FeatureIDSetIndex A primitive may have multiple feature ID sets, so
+   * this allows a feature ID set to be specified by index. This value should
+   * index into the array of CesiumFeatureIdSets in the CesiumPrimitiveFeatures.
+   * If the specified feature ID set index is invalid, this returns -1.
+   */
+  UFUNCTION(
+      BlueprintCallable,
+      BlueprintPure,
+      Category = "Cesium|Primitive|Features")
+  static int64 GetFeatureIDFromHit(
+      UPARAM(ref) const FCesiumPrimitiveFeatures& PrimitiveFeatures,
+      const FHitResult& Hit,
+      int64 FeatureIDSetIndex = 0);
+};