Add existing to tracked

node_modules/@cesium/engine/Source/Scene/findGroupMetadata.js

@@ -0,0 +1,39 @@
+import defined from "../Core/defined.js";
+import hasExtension from "./hasExtension.js";
+
+/**
+ * Check if a content has metadata, either defined in its metadata field (3D Tiles 1.1)
+ * or in the <code>3DTILES_metadata</code> extension. If so, look up the group with the
+ * corresponding ID.
+ *
+ * @function
+ *
+ * @param {Cesium3DTileset} tileset The tileset to query for group metadata
+ * @param {object} contentHeader the JSON header for a {@link Cesium3DTileContent}
+ * @return {GroupMetadata} the group metadata, or <code>undefined</code> if not found
+ * @private
+ * @experimental This feature is using part of the 3D Tiles spec that is not final and is subject to change without Cesium's standard deprecation policy.
+ */
+function findGroupMetadata(tileset, contentHeader) {
+  const metadataExtension = tileset.metadataExtension;
+  if (!defined(metadataExtension)) {
+    return undefined;
+  }
+  const groups = metadataExtension.groups;
+
+  const group = hasExtension(contentHeader, "3DTILES_metadata")
+    ? contentHeader.extensions["3DTILES_metadata"].group
+    : contentHeader.group;
+
+  if (typeof group === "number") {
+    return groups[group];
+  }
+
+  const index = metadataExtension.groupIds.findIndex(function (id) {
+    return id === group;
+  });
+
+  return index >= 0 ? groups[index] : undefined;
+}
+
+export default findGroupMetadata;