Add existing to tracked

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

@@ -0,0 +1,50 @@
+import DeveloperError from "../Core/DeveloperError.js";
+
+/**
+ * The subdivision scheme for an implicit tileset.
+ *
+ * @enum {string}
+ * @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.
+ */
+const ImplicitSubdivisionScheme = {
+  /**
+   * A quadtree divides a parent tile into four children, split at the midpoint
+   * of the x and y dimensions of the bounding box
+   * @type {string}
+   * @constant
+   * @private
+   */
+  QUADTREE: "QUADTREE",
+  /**
+   * An octree divides a parent tile into eight children, split at the midpoint
+   * of the x, y, and z dimensions of the bounding box.
+   * @type {string}
+   * @constant
+   * @private
+   */
+  OCTREE: "OCTREE",
+};
+
+/**
+ * Get the branching factor for the given subdivision scheme
+ * @param {ImplicitSubdivisionScheme} subdivisionScheme The subdivision scheme
+ * @returns {number} The branching factor, either 4 for QUADTREE or 8 for OCTREE
+ * @private
+ */
+ImplicitSubdivisionScheme.getBranchingFactor = function (subdivisionScheme) {
+  switch (subdivisionScheme) {
+    case ImplicitSubdivisionScheme.OCTREE:
+      return 8;
+    case ImplicitSubdivisionScheme.QUADTREE:
+      return 4;
+    //>>includeStart('debug', pragmas.debug);
+    default:
+      throw new DeveloperError("subdivisionScheme is not a valid value.");
+    //>>includeEnd('debug');
+  }
+};
+
+Object.freeze(ImplicitSubdivisionScheme);
+
+export default ImplicitSubdivisionScheme;