+ * @brief UI control rendering mode (default mode).
+ *
+ * This mode is designed for UI controls. In this mode renderer order will be respective to tree hierarchy of Actors.
+ * This mode is expected to have better performance than LAYER_3D as renderers can be sorted more efficiently.
+ *
+ * For the following actor tree the rendering order will be A first, then B & C and finally D,E,F regardless of their
+ * Z positions.
+ * Rendering order between siblings, such as D, E & F or B & C, is determined based on the renderers depth index.
+ * In UI we don't normally expect overlap. If you have two overlapped actors, make them parent-child to guarantee order of all renderers.
+ *
+ * @code
+ *
+ * Layer1 (parent)
+ * |
+ * A
+ * / \
+ * B C
+ * / \ \
+ * D E F
+ *
+ * @endcode
+ *
+ * @SINCE_1_1.45
+ */
+ LAYER_UI = LAYER_2D,
+
+ /**
+ * @brief Layer will use depth test.