Add existing to tracked

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

@@ -0,0 +1,78 @@
+// @ts-check
+
+import BlendEquation from "./BlendEquation.js";
+import BlendFunction from "./BlendFunction.js";
+
+/**
+ * The blending state combines {@link BlendEquation} and {@link BlendFunction} and the
+ * <code>enabled</code> flag to define the full blending state for combining source and
+ * destination fragments when rendering.
+ * <p>
+ * This is a helper when using custom render states with {@link Appearance#renderState}.
+ * </p>
+ *
+ * @namespace
+ */
+const BlendingState = {
+  /**
+   * Blending is disabled.
+   *
+   * @type {object}
+   * @constant
+   */
+  DISABLED: Object.freeze({
+    enabled: false,
+  }),
+
+  /**
+   * Blending is enabled using alpha blending, <code>source(source.alpha) + destination(1 - source.alpha)</code>.
+   *
+   * @type {object}
+   * @constant
+   */
+  ALPHA_BLEND: Object.freeze({
+    enabled: true,
+    equationRgb: BlendEquation.ADD,
+    equationAlpha: BlendEquation.ADD,
+    functionSourceRgb: BlendFunction.SOURCE_ALPHA,
+    functionSourceAlpha: BlendFunction.ONE,
+    functionDestinationRgb: BlendFunction.ONE_MINUS_SOURCE_ALPHA,
+    functionDestinationAlpha: BlendFunction.ONE_MINUS_SOURCE_ALPHA,
+  }),
+
+  /**
+   * Blending is enabled using alpha blending with premultiplied alpha, <code>source + destination(1 - source.alpha)</code>.
+   *
+   * @type {object}
+   * @constant
+   */
+  PRE_MULTIPLIED_ALPHA_BLEND: Object.freeze({
+    enabled: true,
+    equationRgb: BlendEquation.ADD,
+    equationAlpha: BlendEquation.ADD,
+    functionSourceRgb: BlendFunction.ONE,
+    functionSourceAlpha: BlendFunction.ONE,
+    functionDestinationRgb: BlendFunction.ONE_MINUS_SOURCE_ALPHA,
+    functionDestinationAlpha: BlendFunction.ONE_MINUS_SOURCE_ALPHA,
+  }),
+
+  /**
+   * Blending is enabled using additive blending, <code>source(source.alpha) + destination</code>.
+   *
+   * @type {object}
+   * @constant
+   */
+  ADDITIVE_BLEND: Object.freeze({
+    enabled: true,
+    equationRgb: BlendEquation.ADD,
+    equationAlpha: BlendEquation.ADD,
+    functionSourceRgb: BlendFunction.SOURCE_ALPHA,
+    functionSourceAlpha: BlendFunction.ONE,
+    functionDestinationRgb: BlendFunction.ONE,
+    functionDestinationAlpha: BlendFunction.ONE,
+  }),
+};
+
+Object.freeze(BlendingState);
+
+export default BlendingState;