Temporal AA? Please explain

[harryinny3]

And with a 9800Pro above XT speeds, is this something i should use?

Thanks for any and all help.


Yes i did a search, but nothing with and explination Came up

Harry

 

[Vrykyl]

Im not sure exactly how it works, im sure Albuquerque can explain the tech stuff, but I think its a way of making the level of AA set look higher than it actually is by some sort of clever ati trickery. Either way it makes for eg, 2x AA look like 4xAA but without any real performance hit....so IMO id use it if you have the option...
anything that makes IQ even better has to be a bonus eh

 

[harryinny3]

Thanks, I do have it set. Im running 4x and 16x. Just installed the driver late lastnight and havent played any games yet. Hopeing for the best.

And if anyone would care to explain the temporal aa that would be great.

Harry

 

[Vrykyl]

After a quick look around i found a few places offering a better explanation than I can give, you might wanna have a read of -

http://forums.anandtech.com/messageview.cfm?catid=31&threadid=1341945&enterthread=y

http://www20.graphics.tomshardware.com/graphic/20040504/ati-x800-08.html

 

[I.M.O.G.]

Very basically, (and possibly even wrong) what it does is use alternating versions of anti-aliasing on each frame, so as the frames fly by and blend together, the resulting picture appears much better than it does by just using a single anti-aliasing method on every frame.

There was a thread started on this... Digging.

not what I was looking for...

First, when you enable temporal AA, it gets better with faster framerate. 4xAA + 2T looks noticeably better at 60fps, but looks WORLDS better at 100fps. The higher the framerate, the better the "blur" affect your eyes give to the edges, and thus the better antialiasing.

Second, because it forces VSYNC, higher refresh rates are better too. To get the most out of this software, play at a resolution where you can get at least an 85hz refresh rate -- more is better.

Third, sustainable framerate is definately key. I set my threshold to 50fps and that's probably the lowest you want to go. Even if they don't flicker, the edges start to noticeably "modulate" as framerate goes down.

And fourth, sometimes DXFSAAViewer doesn't always pick it up. I entered the proper registry keys, rebooted, enabled AA to 2x and started the viewer and was able to see the cool pattern. I exited the viewer, bumped up the AA to 4x, and started the viewer again -- only to get NO antialiasing. Wha? Bumped it to 6x, restarted the viewer, and got the appropriate 6x2TAA.

This is the thread I was looking for... Check out this link to see the right up and a formal explanation:

http://69.93.88.162/page.php?pageid=4533&head=1&comments=1

 

[Albuquerque]

You have it right: the AA sample pattern alternates on each frame. If you are running 2T, it flips between two sample patterns. If you are running 3T, it flips between three sample patterns. Changing the sample patterns doesn't take any performance away from the card, so essentially turning up the temporal AA slider has no impact on performance.

The theory is that a 2xAA + 2T (2xtemporal AA) will give you the net effect of a real 4xAA. Thus, 4xAA + 2T = 8xAA. 6xAA + 2T = 12xAA. But all this theory only holds true if you can keep your framerate high enough to be visibly smooth -- which will vary from person to person. Some will find 60fps smooth enough, others will wince until it comes up around 100.

FarCry hates temporal AA, or at least it did the last time I checked -- my computer has been out of commission since the end of May, something might have changed during all this time . FarCry exibits blocky artifacts almost like a 9500np hardmod gone wrong, but it only generates those artifacts on polygon edges.

With the horsepower available in the x800 series, temporal AA has a lot more usability. The 9800 series work pretty good too, but they still dip below 60fps enough times (at least, in strenuous games like FarCry or Halo or the like) that temporal AA show weaknesses.