[comp.windows.x] another hack for unexpose events

rws@EXPO.LCS.MIT.EDU (Bob Scheifler) (12/09/88)

Alternatively, set the background of your window to None,
and issue an XClearArea requesting exposures, then set
your background back to what it should be.  (To be
completely safe you should probably do all of this in
a GrabServer).  The exposure events you get back will
tell you instantaneously what regions are visible, without
having actually damaged your window contents.