Add existing to tracked

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

@@ -0,0 +1,31 @@
+/**
+ * A class containing a set of flags indicating which parts of an
+ * <code>ImageryLayer</code> need to be processed.
+ *
+ * This is used in the <code>ImageryPipelineStage</code> to decide the
+ * structure of the function that blends the imagery texture information
+ * with the previous pixels.
+ *
+ * Each flag indicates that at least one of the <code>ImageryLayer</code> objects
+ * that are part of the input did <b>not</b> have the default value that
+ * was defined via the corresponding <code>ImageryLayer.DEFAULT_...</code>>.
+ *
+ * Note that the type of the flags can be <code>boolean</code> or
+ * <code>number</code>. Users should check for these flags having
+ * a 'truthy' or 'falsy' value.
+ *
+ * @private
+ */
+class ImageryFlags {
+  constructor() {
+    this.alpha = false;
+    this.brightness = false;
+    this.contrast = false;
+    this.hue = false;
+    this.saturation = false;
+    this.gamma = false;
+    this.colorToAlpha = false;
+  }
+}
+
+export default ImageryFlags;