Roland Scheidegger wrote: > On 23.10.2009 08:37, Maciej Cencora wrote: >> Hi, >> >> as you may already know r300 classic driver is in pretty good shape these >> days, but there's one thing that causes major slowdowns in many games: lack >> of >> hardware accelerated blit operation. > The same is true for r100/r200... > >> Currently all glCopyTex[Sub]Image operations are done through span functions >> which is slow as hell. >> We could use the hw blitter unit, but using it causes stalls because of the >> 2D/3D mode switch. > A long time ago I implemented this as a hack for r200 (just blit > directly to the texture in vram, so never touching the backup texture in > system memory). Worked quite well in practice (good enough for doom3 > special effects). I didn't notice any obvious slowdowns due to 2d/3d > sync issues (though maybe I didn't do any syncs...). > >> I was wondering how this could be fixed and I got this crazy idea of porting >> the everything-is-texture concept from gallium to classic mesa. Actually not >> all of it, just the pieces that make the renderbuffers look like textures >> for >> the driver. > You could probably just try to hack up a blit using 3d engine? Though of > course lots of setup would be needed. Nice thing about not using blitter > (apart from potential performance issues) is of course that you can > also support format conversion for free. > >> Brian, what do you think about this idea? Is it feasible and worth doing? >> Maybe you have better ideas how to resolve this issue? > Not sure what Brian's opinion on that is, but I'm not sure if there's > really much point in trying to port over half of gallium to classic > mesa. Looks to me like time might be better spent working on gallium > drivers instead...
Yeah, I'd probably opt to work on the gallium driver rather than spend a lot of time and effort on the original driver. -Brian ------------------------------------------------------------------------------ Come build with us! The BlackBerry(R) Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9 - 12, 2009. Register now! http://p.sf.net/sfu/devconference _______________________________________________ Mesa3d-dev mailing list Mesa3d-dev@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mesa3d-dev
