Types of AA - CSAA vs MSAA vs 16xQ CSAA

Jul 29, 2006
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Sorry if this has been answered before, I've tried wikipedia to begin with then moved to google then moved to a forum search and couldn't find much.. I just got a GTX 280 and my old rig has new life :) I'm playing Left 4 Dead and feel like I can probably push higher than the 2x I was doing with my last card, but there are so many options!

CSAA
MSAA
16xQ CSAA

I know the different multipliers are a case of "higher is better" but what about the other types? If anyone is generous enough to give a full explanation (or link to one) I'm very curious and would love learn more, but I'd be super grateful also for just a quick "this is the best looking option" answer, if there is a clear answer.

Thank you in advance for any help!!
 

AzN

Banned
Nov 26, 2001
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CSAA is actually just 4xAA with more coverage samples.

Q is plain old MSAA.
 

chizow

Diamond Member
Jun 26, 2001
9,537
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Bit-Tech AA Basics
Bit-Tech Transparency AA Basics

Those are some good places to start, although they won't give you a great comparison of the different sampling techniques in practice. Even comparing AA SS will only get you so far as you'll have to zoom way in until each pixel looks like a sugar cube to see any difference beyond 4xAA.

It typically comes down to more samples = better quality = worst performance. The #x multiplier isn't really a good indication of # of samples or performance, but it usually is a pretty good gauge of performance. Some of the coverage sample techniques used with newer cards however can offer better AA without too much more performance hit though.
 

Cookie Monster

Diamond Member
May 7, 2005
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Ok here are the basics. nVIDIA has LOADS of different AA settings that can be used through this program called nhancer. Ill just go over coverage sample AA, or CSAA.

You have 8xCSAA, 8xQ, 16xCSAA and 16xQ. 8xCSAA is basically 4xMSAA+ 4 "possible" coverage samples. This means that the lowest quality in a scene could be a minimum of 4xAA, and the highest quality could be 8xAA (This varies depending on the number of coverage samples within the scene). 8xQ is basically 8xMSAA. 16xCSAA follows the same principle as 8xCSAA except that it uses 8 coverage samples meaning the highest quality could be as high as 16xAA. 16xQ isnt 16xMSAA but rather a more higher level of 16xCSAA, with a minimum of 8 multi samples (so 8xAA is the minimum in any given scene) and 8 coverage samples.

So basically, CSAA is a very good AA when it comes to memory buffer efficiency and performance as 16xCSAA is usually 10~20% slower than 4xMSAA.