+ /**
+ * The ComponentLayer of a Component instance indicates its relative stacking order
+ * with respect to the onscreen visual representation of the UI.
+ * ComponentLayer, in combination with Component bounds information, can be used
+ * to compute the visibility of all or part of a component. This is important in
+ * programmatic determination of region-of-interest for magnification, and in
+ * ¨flat screen review¨ models of the screen, as well as for other uses.
+ * Objects residing in two of the ComponentLayer categories support
+ * further z-ordering information, with respect to their peers in the same layer:
+ * namely, LAYER_WINDOW and LAYER_MDI. Relative stacking order for other objects within
+ * the same layer is not available; the recommended heuristic is ¨first child paints first¨,
+ * in other words, assume that the first siblings in the child list are subject to being
+ * overpainted by later siblings if their bounds intersect.
+ *
+ * The order of layers, from bottom to top, is:
+ * \li LAYER_BACKGROUND
+ * \li LAYER_WINDOW
+ * \li LAYER_MDI
+ * \li LAYER_CANVAS
+ * \li LAYER_WIDGET
+ * \li LAYER_POPUP
+ * \li LAYER_OVERLAY
+ */