OpenGL man pages
glXWaitGL - complete GL execution prior to subsequent X calls
void glXWaitGL( void )
OpenGL rendering calls made prior to glXWaitGL are guaranteed to be
executed before X rendering calls made after glXWaitGL. Although this same
result can be achieved using glFinish, glXWaitGL does not require a round
trip to the server, and it is therefore more efficient in cases where
client and server are on separate machines.
glXWaitGL is ignored if there is no current GLX context.
glXWaitGL may or may not flush the X stream.
GLXBadCurrentWindow is generated if the drawable associated with the
current context of the calling thread is a window, and that window is no
glFinish, glFlush, glXWaitX, XSync
Fri Dec 6 11:18:03 EST 1996
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