Add existing to tracked

node_modules/@cesium/engine/Source/Scene/Model/ModelLightingOptions.js

@@ -0,0 +1,29 @@
+import Frozen from "../../Core/Frozen.js";
+import LightingModel from "./LightingModel.js";
+
+/**
+ * Options for configuring the {@link LightingPipelineStage}
+ *
+ * @param {object} options An object containing the following options
+ * @param {LightingModel} [options.lightingModel=LightingModel.UNLIT] The lighting model to use
+ *
+ * @alias ModelLightingOptions
+ * @constructor
+ *
+ * @private
+ */
+function ModelLightingOptions(options) {
+  options = options ?? Frozen.EMPTY_OBJECT;
+
+  /**
+   * The lighting model to use, such as UNLIT or PBR. This is determined by
+   * the primitive's material.
+   *
+   * @type {LightingModel}
+   *
+   * @private
+   */
+  this.lightingModel = options.lightingModel ?? LightingModel.UNLIT;
+}
+
+export default ModelLightingOptions;