glutLayerGet -- retrieves GLUT state pertaining to the layers of the current window.
int glutLayerGet (GLenum info);
GLUT_OVERLAY_POSSIBLE
Whether an overlay could be established for the current window
given the current initial display mode. If false, glutEstab-
lishOverlay will fail with a fatal error if called.
GLUT_LAYER_IN_USE
Either GLUT_NORMAL or GLUT_OVERLAY depending on whether the
normal plane or overlay is the layer in use.
GLUT_HAS_OVERLAY
If the current window has an overlay established.
GLUT_TRANSPARENT_INDEX
The transparent color index of the overlay of the current win-
dow; negative one is returned if no overlay is in use.
GLUT_NORMAL_DAMAGED
True if the normal plane of the current window has damaged (by
window system activity) since the last display callback was
triggered. Calling glutPostRedisplay will not set this true.
GLUT_OVERLAY_DAMAGED
True if the overlay plane of the current window has damaged (by
window system activity) since the last display callback was
triggered. Calling glutPostRedisplay or glutPostOverlayRedis-
play will not set this true. Negative one is returned if no
overlay is in use.
glutLayerGet retrieves GLUT layer information for the current window represented by integers. The info parameter determines what type of layer information to return.
glutEstablishOverlay, glutUseOverlay, glutCreateWindow, glutSetColor,