初始提交: UE5.3项目基础框架

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

@@ -0,0 +1,165 @@
+// Copyright 2020-2024 CesiumGS, Inc. and Contributors
+
+#pragma once
+
+#include "Kismet/BlueprintFunctionLibrary.h"
+#include <CesiumGltf/AccessorUtility.h>
+#include "CesiumFeatureIdAttribute.generated.h"
+
+namespace CesiumGltf {
+struct Model;
+struct Accessor;
+struct Node;
+} // namespace CesiumGltf
+
+/**
+ * @brief Reports the status of a FCesiumFeatureIdAttribute. If the feature ID
+ * attribute cannot be accessed, this briefly indicates why.
+ */
+UENUM(BlueprintType)
+enum class ECesiumFeatureIdAttributeStatus : uint8 {
+  /* The feature ID attribute is valid. */
+  Valid = 0,
+  /* The feature ID attribute does not exist in the glTF primitive. */
+  ErrorInvalidAttribute,
+  /* The feature ID attribute uses an invalid accessor in the glTF. */
+  ErrorInvalidAccessor
+};
+
+/**
+ * @brief A blueprint-accessible wrapper for a feature ID attribute from a glTF
+ * model. Provides access to feature IDs which can be used with the
+ * corresponding {@link FCesiumPropertyTable} to access metadata. These feature
+ * IDs may be defined per-vertex or per-instance.
+ */
+USTRUCT(BlueprintType)
+struct CESIUMRUNTIME_API FCesiumFeatureIdAttribute {
+  GENERATED_USTRUCT_BODY()
+
+public:
+  /**
+   * @brief Constructs an empty feature ID attribute instance. Empty feature ID
+   * attributes can be constructed while trying to convert a FCesiumFeatureIdSet
+   * that is not an attribute. In this case, the status reports it is an invalid
+   * attribute.
+   */
+  FCesiumFeatureIdAttribute()
+      : _status(ECesiumFeatureIdAttributeStatus::ErrorInvalidAttribute),
+        _featureIdAccessor(),
+        _attributeIndex(-1) {}
+
+  /**
+   * @brief Constructs a feature ID attribute instance.
+   *
+   * @param Model The model.
+   * @param Primitive The mesh primitive containing the feature ID attribute.
+   * @param FeatureIDAttribute The attribute index specified by the FeatureId.
+   * @param PropertyTableName The name of the property table this attribute
+   * corresponds to, if one exists, for backwards compatibility.
+   */
+  FCesiumFeatureIdAttribute(
+      const CesiumGltf::Model& Model,
+      const CesiumGltf::MeshPrimitive& Primitive,
+      const int64 FeatureIDAttribute,
+      const FString& PropertyTableName);
+
+  /**
+   * @brief Constructs a feature ID attribute instance from
+   * EXT_instance_features data.
+   *
+   * @param Model The model.
+   * @param Node The node containing the feature ID attribute.
+   * @param FeatureIDAttribute The attribute index specified by the FeatureId.
+   * @param PropertyTableName The name of the property table this attribute
+   * corresponds to, if one exists, for backwards compatibility.
+   */
+  FCesiumFeatureIdAttribute(
+      const CesiumGltf::Model& Model,
+      const CesiumGltf::Node& Node,
+      const int64 FeatureIDAttribute,
+      const FString& PropertyTableName);
+
+  /**
+   * Gets the index of this feature ID attribute in the glTF primitive.
+   */
+  int64 getAttributeIndex() const { return this->_attributeIndex; }
+
+private:
+  ECesiumFeatureIdAttributeStatus _status;
+  CesiumGltf::FeatureIdAccessorType _featureIdAccessor;
+  int64 _attributeIndex;
+
+  // For backwards compatibility.
+  FString _propertyTableName;
+
+  friend class UCesiumFeatureIdAttributeBlueprintLibrary;
+};
+
+UCLASS()
+class CESIUMRUNTIME_API UCesiumFeatureIdAttributeBlueprintLibrary
+    : public UBlueprintFunctionLibrary {
+  GENERATED_BODY()
+
+public:
+  PRAGMA_DISABLE_DEPRECATION_WARNINGS
+  /**
+   * Get the name of the feature table corresponding to this feature ID
+   * attribute. The name can be used to fetch the appropriate
+   * FCesiumFeatureTable from the FCesiumMetadataModel.
+   */
+  UFUNCTION(
+      BlueprintCallable,
+      BlueprintPure,
+      Meta =
+          (DeprecatedFunction,
+           DeprecationMessage =
+               "Use GetPropertyTableIndex on a CesiumFeatureIdSet instead."))
+  static const FString&
+  GetFeatureTableName(UPARAM(ref)
+                          const FCesiumFeatureIdAttribute& FeatureIDAttribute);
+  PRAGMA_ENABLE_DEPRECATION_WARNINGS
+
+  /**
+   * Gets the status of the feature ID attribute. If this attribute is
+   * invalid in any way, this will briefly indicate why.
+   */
+  UFUNCTION(
+      BlueprintCallable,
+      BlueprintPure,
+      Category = "Cesium|Features|FeatureIDAttribute")
+  static ECesiumFeatureIdAttributeStatus GetFeatureIDAttributeStatus(
+      UPARAM(ref) const FCesiumFeatureIdAttribute& FeatureIDAttribute);
+
+  /**
+   * Gets the number of elements in the attribute. This is distinct from the
+   * number of unique feature IDs within the attribute.
+   *
+   * For a feature ID attribute of a regular mesh, this is the number of
+   * vertices. For a per-instance feature ID, this is the number of instances.
+   *
+   * If the feature ID attribute is invalid, this returns 0.
+   */
+  UFUNCTION(
+      BlueprintCallable,
+      BlueprintPure,
+      Category = "Cesium|Features|FeatureIDAttribute")
+  static int64
+  GetCount(UPARAM(ref) const FCesiumFeatureIdAttribute& FeatureIDAttribute);
+
+  /**
+   * Gets the feature ID at the given index. A feature ID can be used with a
+   * FCesiumPropertyTable to retrieve the metadata for that ID. If the feature
+   * ID attribute is invalid, this returns -1.
+   *
+   * For a feature ID attribute of a regular mesh, the provided Index is the
+   * index of a vertex within the mesh. For a per-instance feature ID, the
+   * provided Index is the index of the instance.
+   */
+  UFUNCTION(
+      BlueprintCallable,
+      BlueprintPure,
+      Category = "Cesium|Features|FeatureIDAttribute")
+  static int64 GetFeatureID(
+      UPARAM(ref) const FCesiumFeatureIdAttribute& FeatureIDAttribute,
+      int64 Index);
+};