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hemmy
05-21-06, 12:32 AM
http://www.rage3d.com/board/showthread.php?t=33856269

Copying from Rage3D post, i dld NVtray, and used the lod tweaks to high (opengl and d3d) and it looks much better

You guys probably know about this already, but incase you didn't it works nicely:

Default LOD:

http://img119.imageshack.us/img119/7003/shot00304qd.jpg

High LOD:

http://img160.imageshack.us/img160/3686/shot00326zc.jpg

hemmy
05-21-06, 12:58 AM
And despite making it look better there is weird stuff going on like a shimmerish tear... :(

NVIDIA better fix those problems

The walls shimmer and tear while the ground is fine, done using that mode :o

rewt
05-21-06, 01:09 AM
Yes adjusting LOD to negative range will bring out more detail in distant textures. Unfortunately it can also cause texture aliasing (technically, texture aliasing is somewhat different than texture shimmering). Combat aliasing by using supersampling AA methods.

FearMeAll
05-21-06, 09:14 AM
this is the same kind of thing that the old omega drivers used to do. It's doing nothing but changing lod. There is no way to get around the shimmering as it is not Nvidia's drivers fault here. It is basically taking away mipmaps and just letting more raw textures sit there with nothing to smooth them over. I'd use anistropic filtering instead.

jolle
05-21-06, 11:34 AM
I think this is why the Clamp Negative LOD setting is there.
Once the LOD goes negative, the mipmaps will be more highres, and when the pixels in the mipmap are smaller then your onscreen pixels you get alot of shimmering and crawling.
Um.. well, not 100% on that acctually, but I think thats what happens (dunno where I got that from tho)..
Anyway I tried a year back or so, and the crawling in CS:S was just insane..

rewt
05-22-06, 02:20 AM
I'd use anistropic filtering instead.

The downside is that AF has a larger performance penalty. Besides, from what I've seen all post-GeForce FX cards still experience shimmering issues anyway. Even if the LOD has been clamped to 0 and with AF enabled.

squall_leonhart
05-22-06, 02:36 AM
Yes adjusting LOD to negative range will bring out more detail in distant textures. Unfortunately it can also cause texture aliasing (technically, texture aliasing is somewhat different than texture shimmering). Combat aliasing by using supersampling AA methods.


super sampling AA is more intensive then standard MS AA.

just use MSAA and max out AF.

squall_leonhart
05-22-06, 02:39 AM
The downside is that AF has a larger performance penalty. Besides, from what I've seen all post-GeForce FX cards still experience shimmering issues anyway. Even if the LOD has been clamped to 0 and with AF enabled.

no it doesn't

AF has no performance penalty on my FX5900XT at 8x at high resolution.

its high AA that causes the performance penalty.

enable lod clamp and set the card to high quality mode, this disables all optimsations and removes shimmering in most cases

SSAA has more performanec penalty then MSAA + AF due to SSAA resampling the entire screen and not just selective textures.

Geforce FX can also do 16xAA, i bet you all didn't know that :D.

rewt
05-22-06, 03:37 AM
no it doesn't

Yes it does. AF is much more GPU intensive than a simple LOD tweak.


AF has no performance penalty on my FX5900XT at 8x at high resolution.

Sure it doesn't.. :rolleyes:


Geforce FX can also do 16xAA, i bet you all didn't know that .

Yeah a lot of us knew that already. Too bad FX 5900 will cry in 16xAA in most cases. Except of course if you're playing Pacman at 640x480 resolution in DirectX7 mode..


just use MSAA and max out AF.

MSAA does nothing to get rid of shimmering. You need SSAA for that.

squall_leonhart
05-22-06, 04:03 AM
Yes it does. AF is much more GPU intensive than a simple LOD tweak.




Sure it doesn't.. :rolleyes:



Yeah a lot of us knew that already. Too bad FX 5900 will cry in 16xAA in most cases. Except of course if you're playing Pacman at 640x480 resolution in DirectX7 mode..



MSAA does nothing to get rid of shimmering. You need SSAA for that.

people seem to think that AF provides a hit, but it really doesn't, i've run various tests on games with AF enabled and disabled and there was only the usual 1% variation in fps.

it was only after enabling AA4x that i recieved any performance hit.

i then disabled AF again and tested again and there was no change from enabling AA, so its my conclusion that AF provides little to no performance hit.

and considering the FX series has the best AF out of any geforce cards. thats pretty acurate,

SSAA is not required to prevent shimmering as SSAA will create more of a performance hit then MSAA and AF combined. due to sampling the entire screen.

all that is required in most cases as i said. is to put the driver into high quality mode, and enable negative lod clamp, and enable Trilinear filtering just for fun. trilinear and AF both can work together as trilinear is a texture filter and AF is a lod filter,

while TF is busy filtering the screen AF is sharpening it.

i've worked with shimmering before.. i know how to fix it.

also there was a set awhile back... i think.. 84.5x or 6x that removed alot of the shimmering.

rewt
05-22-06, 04:40 AM
i know how to fix it.

Not hard. Especially since FX cards don't experience shimmering..

On newer nVidia cards (Geforce 6+), forcing High Quality mode and enabling clamp still doesn't get rid of it completely. Which is why I stated to use SSAA because of its ability to sharpen textures as well. Again, MSAA doesn't do that.

Your statement about AF not impacting performance simply doesn't hold up in everyday gaming and benchmarking scenerios. Its been discussed before, and the general consensus is that you're mislead.

squall_leonhart
05-22-06, 04:46 AM
no, but if you disable the optmisations then that can.

btw, if you enable the MIP filter, the FX series does get shimmering in certain games.

and texture banding.

but don't blame nvidia for shimmering.

that is solely our fault for bitching about the AF performance of the FX series on lower end cards. (which im still yet to find a detailed comparison between having AF on and AF off that shows that AF is as performance consuming as people say...)

rewt
05-22-06, 04:52 AM
no, but if you disable the optmisations then that can.


Forcing High Quality mode does disable all the optimizations..

squall_leonhart
05-22-06, 05:02 AM
yeah i know. my eyes are blurring :P.

hmm i read something somewhere that putting the Lod value to -1 fixes shimmering... i can't remember or confirm where i read it though.