glutVisibilityFunc(3GLUT)            GLUT            glutVisibilityFunc(3GLUT)



NAME
       glutVisibilityFunc  - sets the visibility callback for the current win-
       dow.

SYNTAX
       void glutVisibilityFunc(void (*func)(int state));

ARGUMENTS
       func      The new visibility callback function.

DESCRIPTION
       glutVisibilityFunc sets the visibility callback for the current window.
       The visibility callback for a window is called when the visibility of a
       window changes. The state callback parameter is either GLUTNOTVISIBLE
       or  GLUTVISIBLE  depending  on  the  current visibility of the window.
       GLUTVISIBLE does not distinguish a window being  totally  versus  par-
       tially  visible.  GLUTNOTVISIBLE means no part of the window is visi-
       ble, i.e., until the window's visibility changes, all further rendering
       to the window is discarded.

       GLUT  considers  a window visible if any pixel of the window is visible
       or any pixel of any descendant window is visible on the screen.

       Passing NUL to glutVisibilityFunc disables the generation of the visi-
       bility callback.

       If  the  visibility  callback  for  a  window is disabled and later re-
       enabled, the visibility status of the window is undefined;  any  change
       in  window  visibility will be reported, that is if you disable a visi-
       bility callback and re-enable the callback, you are guaranteed the next
       visibility change will be reported.

SEE ALSO
       glutCreateWindow, glutPopWindow

AUTHOR
       Mark J. Kilgard (mjk@nvidia.com)



GLUT                                  3.7            glutVisibilityFunc(3GLUT)