A look at IQ at Firingsquad...

I assume that you are using the default settings for this app? In which case, are there that many games that occur in a tube?

 

Do you know Half life 1?

I have some games, which use natural terrains. In this games you can see the angle-dependence of ATi's AF-implementation.

 

Of course there are, however Saying "But Nvidia's 4x AF and ATi's 16x AF are equal when you looking at this numbers" is fairly meaninless since it doesn't relate to any gaming situation - its going to be highly dependant on the scene, not a lot of which are going to be similar to what is displayed here. I just think this number from this test is fairly inane since I could just as easily show you other numbers from that test show ATI equalling or besting NVIDIA's numbers with some setups that just as equally don't relate to any gaming environments.

We can all see what the limitation is, however how it is actually represented is far too variable within gaming environments.

 

Well, while there clearly is an issue with ATI's filtering solution does that outweight the issues with the FX's shader rendering performance? Not for me - these results were shocking...

 

I would rather play games at 1fps with NV's QCX mode and bilinear filtering than Ati's 6xAA and 16xAF at 60fps.

 

Well you're either a very, very, VERY silly little manchild or a complete "enthusiasts-of-one-brand-over-the-facts" with that attitude K.I.L.E.R.

EDITED BITS: I forgot that B3D's word filter blanks out fanboy, so I went and changed it to avoid offense.

 

funnily, the "tubes" in half life 1 are really not very tube like (6 or 8 sided, IIRC), and might end up looking better on ATI hardware...

 

I'm pretty sure K.I.L.L.E.R is being sarcastic there.

 

A user on R3D has made a new discovery with Nascar and ATI cards...

http://www.rage3d.com/board/showthread.php?s=&postid=1332195017#post1332195017

 

Isn't this "it does more work so it's better image quality" the same thing that was shot down in the trilinear argument, when it was pointed out that you could do work on texture levels that weren't visible, and while this would increase the workload, it wouldn't improve the image quality.

 

I don't see how this is the same thing at all. NVIDIA's AF method is doing more work because it filters at all angles, while ATI does not. ATI is saving work by not using the maximum degree of AF at certain angles when those angles are present.

So as others have pointed out already, at worst case, with all angles present NVIDIA's 4x can be doing as much work as ATI's 16x. This is a gross overstatement, of course, because most games are not made up of such scenes. It obviously does affect image quality when off angles are not filtered entirely, and work that would otherwise be done is avoided.

 

I really do like QCX AA over ANY AA mode I have seen.

 

At 1 fps as you previously stated?

 

sure, just one fps; but that blur effect makes everything seem more fluid.

 

I always did state, the lower the framerate the more time I have to enjoy the scenary.

 

r3xxs AF does drop to ~2x at the off angles.
However the 45 degree angles also benifit from 16xAF against 8x, look at the green mip level, it moves inwards as do all except the red one if you run the app for yourself.

not nessecarily, both cards take the same number of AA samples at 4x but one is clearly better than the other in final output...

 

AFAIK, ATI is not saving work by not using the maximum degree of AF at certain angles, but by the method they use to calculate samples. Not using the maximum degree of AF at certain angles is just another result of that method (alongside greater performance).

The performance difference between the GF AF and ATI's method is still apparent in scenes without surfaces at odd angles, and I don't recall the performance difference associating with the amount of "full AF" angle surfaces present in the scene.

 

I was under the impression that not using the maximum number of samples(adapative technique which is employed by all IHVs) and limiting the number of maximum samples(off-angle problem) were mutually exclusive.

That really doesn't say anything, even if it is true. All it tells us is that ATI's algorithm is different or possibly more aggressive than NVIDIA's.

From memory, the performance hit of R300's Performance AF is very small, just like R200's AF. R300 has less of an angle problem, because it does maximum filtering at 45 degrees whereas R200 didn't. As far as I'm aware this doesn't seem to decrease performance much at all, which leads me to believe that performing the "correct" filtering at every angle and taking a variable number of samples is mutually exclusive and not inclusive.

 

I agree. (I'm not sure if you were the one who put this idea in my head in the past, or if I figured it out on my own, but this makes a good deal of sense when you consider how AF sample points would be calculated.)

:? Why wouldn't there be a relative performance advantage by virtue of using higher mipmap levels on the off-angle surfaces?