Anisotropic filtering: no drop in FPS?

[JaXXoN]

Hi!

I'm just doing some benchmarking with several 7000 series
cards and an 8800GTX and i have recognized that setting
__GL_LOG_MAX_ANISO has very little or no effect concerning
the frames per second measured for UT2004 (UMark-ONS) and
Enemy Territory (Radar demo).

When setting the environment variable to 1,2,3 or 4, i think
i'm experiencing the "shimmering effect" as discussed at:
http://www.nvnews.net/vbulletin/showthread.php?t=64727
The suggested solution also works for me (at least the
shimmering seems to be reduced but doesn't fully disapear),
so i guess AF is actually working for me in some way.

Now the situation is that there is only a drop from 64 FPS
to 60 FPS when enabling any AF level for a 7300GT and there
is no difference at all for 7800GTX, 7950GT and 8800GTX
(any AF levels).

Since AF is "computationally expensive", i would have suspected
that FPS results should drop for higher AF levels?!

BTW.: FSAA results look "good", means: for the 7300GT, FPS
results drop for increasing modes, while it almost makes no
difference for the 8800GTX. The 7800GTX and the 7950GT do
sort in between. This is what i would have expected, but the
AF behaviour sounds strange to me ...

Any feedback is highly appreciated!

regards

Bernhard

[Enverex]

I remember this, I've always been able to use AF on games that stressed that card quite a lot without it slowing down. Never understood why but it's nice that AF seems to only have a tiny performance hit if at all.