Add existing to tracked

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

@@ -0,0 +1,54 @@
+// @ts-check
+
+/**
+ * The vertical location of an origin relative to an object, e.g., a {@link Billboard}
+ * or {@link Label}.  For example, setting the vertical origin to <code>TOP</code>
+ * or <code>BOTTOM</code> will display a billboard above or below (in screen space)
+ * the anchor position.
+ * <br /><br />
+ * <div align='center'>
+ * <img src='Images/Billboard.setVerticalOrigin.png' width='695' height='175' /><br />
+ * </div>
+ *
+ * @enum {number}
+ *
+ * @see Billboard#verticalOrigin
+ * @see Label#verticalOrigin
+ */
+const VerticalOrigin = {
+  /**
+   * The origin is at the vertical center between <code>BASELINE</code> and <code>TOP</code>.
+   *
+   * @type {number}
+   * @constant
+   */
+  CENTER: 0,
+
+  /**
+   * The origin is at the bottom of the object.
+   *
+   * @type {number}
+   * @constant
+   */
+  BOTTOM: 1,
+
+  /**
+   * If the object contains text, the origin is at the baseline of the text, else the origin is at the bottom of the object.
+   *
+   * @type {number}
+   * @constant
+   */
+  BASELINE: 2,
+
+  /**
+   * The origin is at the top of the object.
+   *
+   * @type {number}
+   * @constant
+   */
+  TOP: -1,
+};
+
+Object.freeze(VerticalOrigin);
+
+export default VerticalOrigin;