[PATCH 1/2] Check for empty vline ranges after clamping.

[Michel Dänzer]

On Sam, 2012-02-04 at 23:14 -0500, Dave Witbrodt wrote: 
> Kudos and thanks to Michel Dänzer for one or both of these:
> 
>    36c19067  Fix vline range calculations.
>    bb0e1531  Check for empty vline ranges after clamping.
> 
> At first, I thought I was imagining things -- everything seemed
> faster after building a new xf86-video-ati.  My previous build had been
> 
>    13b3aed4  EXA/r6xx+: fix rop setting for overlapping copies
> 
> which is the commit just before the latest ones, so my new build only 
> involved the two commits mentioned above.  (I also left the other parts 
> of the X stack unchanged:  libdrm, xorg-server, and mesa.  My kernel is 
> 3.2.4 + many cherry-picks from drm-fixes and drm-next, but when I built 
> it today there was no immediate effect; the speed-up occurred only after 
> the rebuild of the radeon driver.)
> 
> The 'torcs' game frame rate always varies over a wide range while 
> playing -- normally 20 to 45 fps on my HD 5750 card, with occasional 
> spikes into the 50' -- but now mostly stays well above 40 fps, usually 
> in the upper 50's.  Since my monitor's refresh rate is only 60 Hz, the 
> performance is now close to a level such that further improvements would 
> make no visible difference (for me).
> 
> The 'prboom-plus' game has no fps indicator, but anyone could perceive 
> the difference between the old and new radeon driver builds.  This is 
> especially true if I maximize the view (hiding the dashboard) and play 
> at fullscreen 1920x1200.  It's like I bought a new video card!  This 
> particular program is now as responsive as it was with my NVidia GeForce 
> 7950 using the proprietary driver.  (That card died in the summer of 
> 2009, and I have been using only ATI/AMD cards since... and those only 
> with the open source radeon driver.)
> 
> 
> Thanks again,

You're very welcome, and although I'm not 100% sure why these make such
a dramatic difference for you, I'm glad anyway. :)


-- 
Earthling Michel Dänzer           |                   http://www.amd.com
Libre software enthusiast         |          Debian, X and DRI developer