+ case GLUT_OVERLAY_POSSIBLE:
+ return 0 ;
+
+ case GLUT_LAYER_IN_USE:
+ return GLUT_NORMAL;
+
+ case GLUT_HAS_OVERLAY:
+ return 0;
+
+ case GLUT_TRANSPARENT_INDEX:
+ /*
+ * Return just anything, which is always defined as zero
+ *
+ * XXX HUH?
+ */
+ return 0;
+
+ case GLUT_NORMAL_DAMAGED:
+ /* XXX Actually I do not know. Maybe. */
+ return 0;
+
+ case GLUT_OVERLAY_DAMAGED:
+ return -1;
+