On Thu, 2006-03-09 at 07:34 -0700, Brian Paul wrote: > David Reveman wrote: > > Biggest problem with using Xgl and compiz on DRI drivers is that I can't > > efficiently update part of the screen. On proprietary drivers it's > > efficiently done by using DrawBuffer (GL_FRONT) and CopyPixels. > > > > The attached patch for mesa 6.4.2 is just something I created to prove > > that Xgl and compiz runs very well on the Intel driver once this is > > fixed. > > > > I'd like to get this solved asap. I suggest that we add support for > > GLX_MESA_copy_sub_buffer. If I remove the CopyPixel hack from my Intel > > driver patch, that's pretty much what we have. > > > > Xgl will use GLX_MESA_copy_sub_buffer instead of CopyPixels when > > available and we'll add protocol support so that compositing managers > > can use it. > > > > Thoughts? > > > > I'll probably go ahead and get this done in the next few days if no one > > objects. > > Is there anything wrong with just using glCopyPixels all the time? If > it's just a matter of speed, we can certainly try to optimize that path.
I just thought that something like GLX_MESA_copy_sub_buffer would be easier to get efficient and as buffer swapping doesn't require a context to be current, I though that could makes things faster for the case where we have screen updates being done synced to vblank in a separate thread (avoiding two context switches every time we update the screen). > > GLX_MESA_copy_sub_buffer is a bit of an old hack and I'm not sure it's > something we want to promote going forward. > > Another option is the new GL_EXT_framebuffer_blit extension which adds > the glBlitFramebufferEXT() function. It's like glCopyPixels() but has > potential for higher speed. Yes, maybe a fast glBlitFramebufferEXT is the best way to go. > > BTW, I think your patch needs to check more state to see if any > per-fragment operations are enabled. Yes, I know. The CopyPixels part is just a ugly temporary thing to prove that it can be fast. -David ------------------------------------------------------- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642 _______________________________________________ Mesa3d-dev mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/mesa3d-dev
