Stylistic changes after code review

Source/CesiumRuntime/Private/CesiumFeatureIdAttribute.cpp

@@ -2,7 +2,6 @@
 
 #include "CesiumFeatureIdAttribute.h"
 #include <CesiumGltf/Accessor.h>
-#include <CesiumGltf/ExtensionExtMeshGpuInstancing.h>
 #include <CesiumGltf/Model.h>
 
 FCesiumFeatureIdAttribute::FCesiumFeatureIdAttribute(

Source/CesiumRuntime/Private/CesiumFeatureIdSet.cpp

@@ -82,7 +82,8 @@ FCesiumFeatureIdSet::FCesiumFeatureIdSet(
   if (pMetadata && _propertyTableIndex >= 0) {
     size_t index = static_cast<size_t>(_propertyTableIndex);
     if (index < pMetadata->propertyTables.size()) {
-      const CesiumGltf::PropertyTable& propertyTable = pMetadata->propertyTables[index];
+      const CesiumGltf::PropertyTable& propertyTable =
+          pMetadata->propertyTables[index];
       std::string name = propertyTable.name.value_or("");
       propertyTableName = FString(name.c_str());
     }
@@ -217,6 +218,18 @@ int64 UCesiumFeatureIdSetBlueprintLibrary::GetFeatureIDForInstance(
 int64 UCesiumFeatureIdSetBlueprintLibrary::GetFeatureIDFromHit(
     UPARAM(ref) const FCesiumFeatureIdSet& FeatureIDSet,
     const FHitResult& Hit) {
+  // FeatureIDs from instanced geometry take precedence.
+  const auto* pInstancedComponent =
+      Cast<UCesiumGltfInstancedComponent>(Hit.Component);
+  if (IsValid(pInstancedComponent)) {
+    const FCesiumInstanceFeatures& instanceFeatures =
+        UCesiumInstanceFeaturesBlueprintLibrary::GetInstanceFeatures(
+            pInstancedComponent);
+    return UCesiumInstanceFeaturesBlueprintLibrary::GetFeatureIDFromInstance(
+        instanceFeatures,
+        Hit.Item);
+  }
+
   if (FeatureIDSet._featureIDSetType == ECesiumFeatureIdSetType::Texture) {
     FCesiumFeatureIdTexture texture =
         std::get<FCesiumFeatureIdTexture>(FeatureIDSet._featureID);
@@ -225,18 +238,6 @@ int64 UCesiumFeatureIdSetBlueprintLibrary::GetFeatureIDFromHit(
         Hit);
   }
 
-  {
-    const auto* pInstancedComponent =
-        Cast<UCesiumGltfInstancedComponent>(Hit.Component);
-    if (IsValid(pInstancedComponent)) {
-      const FCesiumInstanceFeatures& instanceFeatures =
-          UCesiumInstanceFeaturesBlueprintLibrary::GetInstanceFeatures(
-              pInstancedComponent);
-      return UCesiumInstanceFeaturesBlueprintLibrary::GetFeatureIDFromInstance(
-          instanceFeatures,
-          Hit.Item);
-    }
-  }
   // Find the first vertex of the face.
   const UCesiumGltfPrimitiveComponent* pGltfComponent =
       Cast<UCesiumGltfPrimitiveComponent>(Hit.Component);

Source/CesiumRuntime/Private/LoadGltfResult.h

@@ -196,7 +196,9 @@ struct LoadNodeResult {
    */
   std::vector<FTransform> InstanceTransforms;
   /**
-   * Instance features
+   * Features from EXT_instance_features. A pointer is used for shared ownership
+   * because there may be multiple primitives in the same mesh belonging to a
+   * single instance.
    */
   TSharedPtr<FCesiumInstanceFeatures> pInstanceFeatures = nullptr;
 };

Source/CesiumRuntime/Public/CesiumFeatureIdAttribute.h

@@ -63,10 +63,11 @@ struct CESIUMRUNTIME_API FCesiumFeatureIdAttribute {
       const FString& PropertyTableName);
 
   /**
-   * @brief Constructs a feature ID attribute instance from instance metadata.
+   * @brief Constructs a feature ID attribute instance from
+   * EXT_instance_features data.
    *
    * @param Model The model.
-   * @param Node The "mesh node" containing the feature ID attribute.
+   * @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.

Source/CesiumRuntime/Public/CesiumFeatureIdSet.h

@@ -30,8 +30,9 @@ enum class ECesiumFeatureIdSetType : uint8 {
 /**
  * @brief A blueprint-accessible wrapper for a feature ID set from a glTF
  * primitive. A feature ID can be defined as a per-vertex attribute, as a
- * feature texture, or implicitly via vertex ID. These can be used with the
- * corresponding {@link FCesiumPropertyTable} to access per-vertex metadata.
+ * feature texture, implicitly via vertex ID, or associated with glTF
+ * instances. These can be used with the corresponding {@link
+ * FCesiumPropertyTable} to access the metadata.
  */
 USTRUCT(BlueprintType)
 struct CESIUMRUNTIME_API FCesiumFeatureIdSet {
@@ -189,12 +190,14 @@ class CESIUMRUNTIME_API UCesiumFeatureIdSetBlueprintLibrary
       int64 VertexIndex);
 
   /**
-   * Gets the feature ID associated with a given instance. The feature ID can be
-   * used with a FCesiumPropertyTable to retrieve the corresponding metadata.
+   * Gets the feature ID associated with a given instance in glTF models using
+   * the EXT_mesh_gpu_instancing and EXT_instance_features extensions. The
+   * feature ID can be used with a FCesiumPropertyTable to retrieve the
+   * corresponding metadata.
    *
    * This returns -1 if the given instance is out-of-bounds, if the feature ID
    * set is not for instances, or if the feature ID set is invalid (e.g., it
-   * contains an invalid feature ID texture).
+   * contains an invalid feature ID attribute).
    */
   UFUNCTION(
       BlueprintCallable,

Source/CesiumRuntime/Public/CesiumInstanceFeatures.h

@@ -23,15 +23,15 @@ struct CESIUMRUNTIME_API FCesiumInstanceFeatures {
 
 public:
   /**
-   * Constructs an empty primitive features instance.
+   * Constructs an empty instance features object.
    */
   FCesiumInstanceFeatures() : _instanceCount(0) {}
 
   /**
-   * Constructs an instance feature.
+   * Constructs an instance feature object.
    *
    * @param Model The model that contains the EXT_instance_features extension
-   * @param Node The node that stores instance data
+   * @param Node The node that stores EXT_instance_features
    * extension
    */
   FCesiumInstanceFeatures(
@@ -52,8 +52,9 @@ class CESIUMRUNTIME_API UCesiumInstanceFeaturesBlueprintLibrary
 
 public:
   /**
-   * Gets the instance features of a glTF primitive component. If component is
-   * not a Cesium glTF primitive component, the returned features are empty.
+   * Gets the instance features of an instanced glTF primitive component. If
+   * component is not an instanced Cesium glTF component, the returned features
+   * are empty.
    */
   UFUNCTION(
       BlueprintCallable,
@@ -63,8 +64,8 @@ class CESIUMRUNTIME_API UCesiumInstanceFeaturesBlueprintLibrary
   GetInstanceFeatures(const UPrimitiveComponent* component);
 
   /**
-   * Gets all the feature ID sets that are associated with the
-   * primitive.
+   * Gets all the feature ID sets that are associated with the features
+   * associated with an instanced primitive.
    */
   UFUNCTION(
       BlueprintCallable,
@@ -86,7 +87,7 @@ class CESIUMRUNTIME_API UCesiumInstanceFeaturesBlueprintLibrary
       ECesiumFeatureIdSetType Type);
 
   /**
-   * Gets the feature ID associated with an instance number
+   * Gets the feature ID associated with an instance at an index.
    *
    */
   UFUNCTION(