message: Create branch if more than one node, not more than zero.
diff: @@ -874,7 +874,7 @@ export class ImdlReader extends GltfReader {
  // If more than one node exists, then we need to create a branch for Node_Root so that elements not associated with
  // any node in the schedule script can be grouped together.
  const nodeKeys = Object.keys(this._nodes);
  - const needBranchForRootNode = nodeKeys.length > 0;
  + const needBranchForRootNode = nodeKeys.length > 1;
  for (const nodeKey of nodeKeys) {
  const meshValue = this._meshes[this._nodes[nodeKey]] as ImdlMesh | undefined;
  