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bagman
09-06-06, 11:47 PM
Hi there
If you enable 8XS ( which I assume is 8X Supersampling ? ) should you set Transparency Antialiasing to off, as by choosing 8XS, Supersampling is enabled by default ??

cheers

fivefeet8
09-07-06, 02:11 AM
Hi there
If you enable 8XS ( which I assume is 8X Supersampling ? ) should you set Transparency Antialiasing to off, as by choosing 8XS, Supersampling is enabled by default ??

cheers

8xS is actually only 2x1 Supersamples and 4x RGMS combined. It's not 8x Supersampling. There is a hidden 16x Super Sampling AA mode which uses 2x2 SS AA combined twice. But it's very bandwidth limiting. There is also a 16xS mode which combines 4x RGMS with 2x2 OGSS. Also very intensive on memory bandwidth.

Anyways, yes, you should also enable Transparency AA to hit all alpha texture edges. If performance is an issue, 4xAA with SS TSAA would work a lot better.

bagman
09-07-06, 04:49 AM
8xS is actually only 2x1 Supersamples and 4x RGMS combined. It's not 8x Supersampling. There is a hidden 16x Super Sampling AA mode which uses 2x2 SS AA combined twice. But it's very bandwidth limiting. There is also a 16xS mode which combines 4x RGMS with 2x2 OGSS. Also very intensive on memory bandwidth.

Anyways, yes, you should also enable Transparency AA to hit all alpha texture edges. If performance is an issue, 4xAA with SS TSAA would work a lot better.

Thanks for the explanation

So what is 8X then compared to 8XS ??
Are you saying that 8XS doesn't have a bigger impact FPS wise, than 8X ??
So any form of Transparency AA ( Multisampling or Supersampling ) can be used with either AA mode ??

Is 8XS similar to 2XQ vs 4X in it's performance impact ?

When yu look at how the AA modes are listed in the Control Panel, would it be fair to say they are listed in the order of their impact on FPS ?? i.e. the lowest impact ( 2X ) to the highest impact ( 16X )

cheers

fivefeet8
09-08-06, 01:33 AM
Thanks for the explanation

So what is 8X then compared to 8XS ??
Are you saying that 8XS doesn't have a bigger impact FPS wise, than 8X ??
So any form of Transparency AA ( Multisampling or Supersampling ) can be used with either AA mode ??

Is 8XS similar to 2XQ vs 4X in it's performance impact ?

When yu look at how the AA modes are listed in the Control Panel, would it be fair to say they are listed in the order of their impact on FPS ?? i.e. the lowest impact ( 2X ) to the highest impact ( 16X )

cheers

Usually, when 8x is listed, it's referring to 8xS. Unless in SLI it means different. But Nvidia card's can't do real 8x Super Sampling. They do however have 2 8xS modes. There is an old 8xS mode which used 2x RGMS and 2x2 OGSS combined. The now default mode for current Nvidia cards is 4xRGMS and 2x1 OGSS.

16x is the most bandwidth hungry of all AA modes. It's 4x4 OGSS. It's all supersampling. It also tends to blur the screen a noticeably because of being Super Sampling AA. Yep, the AA modes are usually set from highest performance lowest increase in AA to slowest performance and highest increase in AA.

ChrisRay did a very good AA comparison between the various AA modes once on this message board. Search the board for Anti Aliasing.