On Fri, 2004-11-19 at 00:44 -0600, Kevin O'Brien wrote: > On Thu, 2004-11-18 at 03:57, Felix KÃhling wrote: > > Am Do, den 18.11.2004 schrieb Kevin O'Brien um 8:03: > > > > There is a problem in the radeon driver WRT to waiting for the refresh. > > The driver can wait for the refresh but there is no guarantee that the > > next operation can take place immediately, because there may still be > > more commands pending in the command queue. Calling glFinish before > > glXSwapBuffers should normally fix this. If there is still visible > > tearing the only reason I could imagine is that the blit from back > > buffer to front buffer takes longer than the vertical retrace. In that > > case page flipping might solve your problem. Set 'Option > > "EnablePageFlip" "true"' in the Device section of xorg.conf or > > XF86Config[-4] respectively. > > Page flipping doesn't work with Merge Frame Buffer, [...]
Sounds like a bug that should be fixed. > Is there a way to ensure the Radeon blits from top to bottom? Sure, by setting the > radeon_accelfuncs.c has code that suggests it is programming the chip > for top down blits. And modifying the code to reverse the blit > direction has no effect on my problem. Sure, by setting the DST_Y_TOP_TO_BOTTOM bit in the DP_CNTL register. Might be a good idea to do that in radeon_cp_dispatch_swap(). > Since blitting is faster than refresh rate, blitting from the top to > bottom should produce a "tear" free display - if the blit begins before > start of active display. That code is only used by the X server for 2D. > If the Radeon is blitting from bottom to top, a "tear" would occur if > the blit is longer than vertical blank when the active picture meets the > blit. You're assuming there's no (scheduling, ...) lag between the vertical blank and the emission of the buffer swap... -- Earthling Michel DÃnzer | Debian (powerpc), X and DRI developer Libre software enthusiast | http://svcs.affero.net/rm.php?r=daenzer ------------------------------------------------------- This SF.Net email is sponsored by: InterSystems CACHE FREE OODBMS DOWNLOAD - A multidimensional database that combines robust object and relational technologies, making it a perfect match for Java, C++,COM, XML, ODBC and JDBC. www.intersystems.com/match8 -- _______________________________________________ Dri-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/dri-devel
