glutLayerGet - retrieves GLUT state pertaining to the lay-
ers of the current window.

glutLayerGet
	glutLayerGet(type) -> None

int glutLayerGet(GLenum info);

info      Name of device information to retrieve.

GLUT_OVERLAY_POSSIBLE
        Whether an overlay could be  established  for  the
        current  window  given the current initial display
        mode. If  false,  glutEstablishOverlay  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  window;  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  glut-
        PostRedisplay 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 glut-
        PostRedisplay or glutPostOverlayRedisplay will not
        set  this  true.  Negative  one  is returned if no
        overlay is in use.

glutLayerGet retrieves GLUT layer information for the cur-
rent  window  represented  by integers. The info parameter
determines what type of layer information to return.

glutEstablishOverlay,  glutUseOverlay,   glutCreateWindow,
glutSetColor

Mark J. Kilgard (mjk@nvidia.com)