http://bugs.freedesktop.org/show_bug.cgi?id=18542
--- Comment #13 from Roland Scheidegger <[EMAIL PROTECTED]> 2008-11-20 10:39:33 PST --- (In reply to comment #12) > Basically what the patch does is at the start of an acceleration call, I stall > the engine until we get to the rising or falling edge or a particular vline. > The vline I chose was the last one of the visible portion of the scanout > buffer. At that point the display controller should be at the start of the > blanking period; the stall drops and rendering continues. Hopefully it > finishes before the blanking period ends. If not you get tearing again; > possibly in a different place. Are you sure it really needs to finish before scanout starts again? Since vblank is something like 4% of total time (with non-reduced blanking), that would mean those blits would need to be fast enough for a sustained rate of 1500 fps. I doubt (at least for the slower chips) that's possible at all (for reasonably sized full-screen video). I thought it should be sufficient if rendering is just ahead of scanout, since AFAIK rasterization happens (roughly) top to bottom. So those 4% should pretty much always be enough for no tearing to happen I think in theory... Though of course it won't do much if compositing is used, at least not without the 2d parts of the patch I guess... -- Configure bugmail: http://bugs.freedesktop.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug. _______________________________________________ xorg-driver-ati mailing list [email protected] http://lists.x.org/mailman/listinfo/xorg-driver-ati
