Bugzilla – Bug 157051
Xgl flickers on intel graphics chips
Last modified: 2006-03-20 11:42:43 UTC
Xgl + compiz flicker a lot on intel graphics chips. Patches pending.
Mostly fixed in stable now.
Two more issues remain: 1) On intel the graphics is only displayed correctly after the first CopyPixel() call. 2) We're still hitting a slow path, as CopyPixel() from the back buffer to the front buffer is not accelerated. Also a context switch is required.
Created attachment 72796 [details] Workaround for issue 1 This is a workaround for issue 1, by specifying a scissor region on the first full screen update.
Submitted to stable. Setting to normal now.
Created attachment 72841 [details] Proposed Mesa patch for Issue 2 This patch is a proposed acceleration of a Mesa functionality important to Xgl (GLX_MESA_copy_sub_buffer). From David: This patch adds direct and indirect rendering support for GLX_MESA_copy_sub_buffer. Intel, r200 and r300 drivers are the only drivers I've implemented support for so far. I've only tried the intel implementation and that seems to be working OK.
Created attachment 72842 [details] Workaround for compiz currently needed for using CopySubBuffer From David: Xgl works quite well with this patch on intel hardware. However, there's currently (at least on Mesa 6.4.2) some issues that causes the intel driver (possibly other drivers as well) to not render the first drawing operation done by Xgl's core context correctly and no operations done by the compositing manager context until CopyPixels is called.
Created attachment 73067 [details] Real fix for scissor issue This is the real fix for issue 1 from David. It should be applied to Mesa, and the workaround can be disabled after 10.1 has been released.
Fixed. Mesa.changes: ------------------------------------------------------------------- Wed Mar 15 18:15:23 CET 2006 - mhopf@suse.de - Fix for bug #157051, issue 1: On intel the graphics is only displayed correctly after a scissor region other than full screen is specified.
Issue 1 is fixed, but issue 2 is still open. However, implications of the Mesa patch are too large for 10.1, and we can assume then included for the next Mesa release.
Sorry, I didn't read carefully. Feel free to reopen if you like.