On Tue, 6 May 2008 13:36:23 +0200 "Johan Walles" <johan.walles@xxxxxxxxx>babbled: > 2008/5/6 Michel Dänzer <michel@xxxxxxxxxxxxxxxxxxxx>:> > On Tue, 2008-05-06 at 13:12 +0200, Johan Walles wrote:> > > 2008/5/6 Samuel Thibault <samuel.thibault@xxxxxxxxxxxx>:> > > > Michel Dänzer, le Tue 06 May 2008 09:37:23 +0200, a écrit :> > > > > On Mon, 2008-05-05 at 15:43 +0100, Samuel Thibault wrote:> > > > > > Michel Dänzer, le Mon 05 May 2008 10:22:19 +0200, a écrit :> > > > > > > On Sun, 2008-05-04 at 20:06 +0200, Johan Walles wrote:> > > > > > > >> > > > > > > > I would like to wait for vertical retrace in an X> > > > > > > > application. How can I do that?> > > > > > > >> > > > > > > > The point would be to avoid flicker in my app by using double> > > > > > > > buffering and update the on-screen image during vertical> > > > > > > > retrace.> > > > > > >> > > > > > > There's no mechanism for this yet in X. Your best bet is> > > > > > > probably to use OpenGL, e.g. the GLX_SGI_swap_control extension.> > > > > >> > > > > > Isn't there a more simple double buffering X extension?> > > > >> > > > > You mean DOUBLE-BUFFER?> > > >> > > > Yes.> > > >> > > > > I'm not really familiar with it, but I know that> > > > > at this time it can't synchronize buffer swaps to the refresh.> > > >> > > > Eww, that would be a pity. At the very beginning of the Extension> > > > documentation (Johan: xspecs/Xext/buffer.PS), it is said `Clients> > > > should be able to [...] Display a series of buffers in a window in> > > > rapid succession to achieve a /smooth/ animation', which is what Johan> > > > wants to eventually achieve AIUI (vertical retrace wait being only one> > > > method, I don't know whether which others could be possible).> > >> > > I don't care about vertical retrace in itself, waiting for vertical> > > retrace would only be a way for me to achieve flicker-free animation> > > in a 2D application. Any other way of doing that would be fine as> > > well.> >> > I think the standard technique for double buffering is to use a pixmap> > as the 'back buffer'.> > How would that help achieving flicker-free animation if it doesn't> wait for vertical retrace? it is flicker free... just not tear-free :) -- ------------- Codito, ergo sum - "I code, therefore I am" --------------The Rasterman (Carsten Haitzler) raster@xxxxxxxxxxxxx _______________________________________________xorg mailing listxorg@xxxxxxxxxxxxxxxxxxxxxxxxx://lists.freedesktop.org/mailman/listinfo/xorg