glXSwapBuffers

GLXSWAPBUFFERS()					     GLXSWAPBUFFERS()



NAME
       glXSwapBuffers - exchange front and back buffers


C SPECIFICATION
       void glXSwapBuffers( Display *dpy,
			    GLXDrawable drawable )

       delim $$

PARAMETERS
       dpy	 Specifies the connection to the X server.

       drawable	 Specifies the drawable whose buffers are to be swapped.

DESCRIPTION
       glXSwapBuffers promotes the contents of the back buffer of drawable to
       become the contents of the front buffer of drawable.  The contents  of
       the  back  buffer  then	become undefined.  The update typically takes
       place during the vertical retrace of the monitor, rather than  immedi-
       ately after glXSwapBuffers is called.

       glXSwapBuffers performs an implicit glFlush before it returns.  Subse-
       quent OpenGL commands may be issued immediately after calling glXSwap-
       Buffers,	 but are not executed until the buffer exchange is completed.

       If drawable was not created with respect to a double-buffered  visual,
       glXSwapBuffers has no effect, and no error is generated.

NOTES
       The  contents  of  the back buffer become undefined after a swap. Note
       that this applies to pbuffers as well as windows.

       All GLX rendering contexts share the same notion of  which  are	front
       buffers and which are back buffers.  One consequence is that when mul-
       tiple clients are rendering to the same double-buffered window, all of
       them  should finish rendering before one of them issues the command to
       swap buffers.  The clients are responsible for implementing this	 syn-
       chronization.   Typically  this	is accomplished by executing glFinish
       and then using a semaphore in shared memory to rendezvous before swap-
       ping.

ERRORS
       GLXBadDrawable is generated if drawable is not a valid GLX drawable.

       GLXBadCurrentWindow  is generated if dpy and drawable are respectively
       the display and drawable associated with the current  context  of  the
       calling	thread,	 and  drawable	identifies a window that is no longer
       valid.

SEE ALSO
       glFlush, glXBindSwapBarrierSGIX,	 glXJoinSwapGroupSGIX,	glXSwapInter-
       valSGI




							     GLXSWAPBUFFERS()