R600/700 Mesa Driver Picks Up Blit Support

[Ex-Cyber]

The new code accelerates glCopyTex(Sub)Image, which is fairly specific. Most 3D apps don't use that (reading back from textures) which is why they already run pretty well. If an app makes use of glCopyTex(Sub)Image it would likely have been REALLY slow before blit support.

Would (or could) this be useful for games/apps that want to "manually" draw on top of a rendered scene (notwithstanding whether this is a good idea in general on modern graphics hardware)? I recall a Wine bug report that turned out to be a game doing something like this (to draw a crosshair, of all things) and cratering its FPS as a result.

[bridgman]

Was it System Shock 2 ?

http://www.phoronix.com/forums/showthread.php?t=19903

If so, I think the issue was that SS2 running under Wine made heavy use of GLReadPixels and GLDrawPixels to push the entire screen back and forth between system and video memory every frame. I don't think those calls have been accelerated with blit - I think I remember someone mentioning that it might be possible but I don't remember where I saw that.

I'm not sufficiently familiar with the Wine code to know if the GL calls which *have* been accelerated by blit could be used here instead of the GLReadPixels and GLDrawPixels calls.

[Zajec]

I believe Wine does use blit. With this patch it's finally possible to see 2D in The Sims 3 inside Wine.

[pingufunkybeat]

Wow!

This commit fixed QuakeLive for me.

I thought it was a 32-bit issue and that it was rendering in software, but apparently, the blitting was slowing it down.

Now it works like a charm. Great work!

[uzi18]

Zajec: what about ... Sims 2?

[Zajec]

Zajec: what about ... Sims 2?

If you ask for real, check http://appdb.winehq.org/objectManage...ation&iId=1942 - unfortunately Wine doesn't run it.

If you refer to me playing The Sims 3, well... I don't

[uzi18]

I don't play too but ... my sister does.

For this r600 blitter ...

before:
$ glxgears
1526 frames in 5.0 seconds = 305.061 FPS
1571 frames in 5.0 seconds = 314.045 FPS
1563 frames in 5.0 seconds = 312.436 FPS

after:
$ glxgears
14826 frames in 5.0 seconds = 2965.130 FPS
15257 frames in 5.0 seconds = 3051.386 FPS
12316 frames in 5.0 seconds = 2463.057 FPS
14367 frames in 5.0 seconds = 2873.343 FPS
15067 frames in 5.0 seconds = 3013.323 FPS
14597 frames in 5.0 seconds = 2919.290 FPS

looks like avarage 10x faster.
World of padman - laggs.

$ sudo lspci |grep RV
08:00.0 VGA compatible controller: ATI Technologies Inc RV770 [Radeon HD 4850]

DDX ati (git/master), Mesa (git/master), kernel 2.6.33-rc1

[bridgman]

Is this with a compositor ? My dim understanding was that the blit code currently accelerated a couple of texture functions which glxgears didn't use, so presumably the speedup must be happening somewhere else in the stack (eg compositor or something).

[uzi18]

No i have disabled (kwin) compositing some time ago (month or two), because after some kms/libdrm/mesa changes it gave me lots of problems.

[monraaf]

Perhaps the glxgears speed-up is because you were previously using the software renderer ? 300 fps sounds like a typical value for the software renderer to me.