nVidia 400 Series Image Quality Analysis
Full Scene Super-Sampling
Like 3dfx and more recently ATi, nVidia now allows full scene super-sampling with rotated and sparse grids. This feature was “accidentally” implemented at launch and was hidden within the TrAA setting, but now it’s supported with nVidia’s tool, and with certain third party utilities. Interestingly enough, SSAA in OpenGL is still “hidden”, so you have to activate it the old way.
While TrAA only affects transparent textures, SSAA affects the entire scene, and thus the two are mutually exclusive. Like ATi, nVidia renders the same scene multiple times with an offset on each sample, and then combines the samples into one. The sample patterns for SSAA are exactly the same as they are for TrAA, except the entire scene is affected instead of just alpha textures.
nVidia’s advantages over ATi include the fact that SSAA functions in DX10/DX11, and also that the samples can be decoupled from the base MSAA level, exactly like TrAA can. Currently nVidia does not adjust the LOD bias automatically like ATi does, but you can use third party utilities to do this.
Below is a floor from Doom 3 showing the infamous shader aliasing, and you can see that 8xSSAA really cleans it up. Even 2xSSAA visibly clears up games with heavy shader aliasing and the performance is often better than 8xS, while also delivering a cleaner image overall.
0xSSAA
2xSSAA
4xSSAA
8xSSAA
The 8000/9000/200 series now supports SSAA too, but only in DX9 and OpenGL.
A very Good article, but they have forgotten, you can mix also the old Hybrid 8xS,8xSQ,16xS,32xS with 2x,4 x or 8xSGSSAA and get even Higher Image Quality.
Yes, you can combine SGSSAA with any mode that has a multi-sampling component, but it’s simply not feasible for me to test all of the possible combinations.
Also modes like 8xSQ and 12xS don’t make sense to be used.
Here All Modis:
http://benchmarks.cwsurf.de/antialiasing/nv_aa_modes.html
You can mix proportion SGSSAA always with the share of MSAA. 4xSGSSAA works with 8xSQ because it has only 2xMSAA, because 2xSGSSAA goes up
8xSQ have 2xMSAA and can 2xSGSSAA
8xS/16xS have 4xMSAA and you can 4xSGSSAA and 2xSGSSAA
32xS have 8xMSAA and you can 2x,4x and 8xSGSSAA
32xS with 8xSGSSAA = 32xSGSSAA
Sorry for my bad English.
That’s a nice chart.
4xSSAA won’t work with 8xSQ because the former only has a 2xMSAA component. It’ll work with 8xS however.
Also 32xCSAA doesn’t have an EER of 32×32, because some of the samples line up.
I think Coverage Samples can do not mix. What good is the automatic LOD Bias with Hybrid+SGSSAA shift, hopefully NVIDIA will assemble a LOD Tweak for the pure SGSSAA modes, I’ve already tried to ask NVIDIA, but so far without success.
Hi BFG10K
Thanks for this review, very informative.
I need your help on something. How did you enable SSAA in Crysis ?
Using nvidiainspector and either enhance or override I cannot get it to apply AA settings in game. I’ve been trying to get 2×2 SSAA working to no avail.
I can’t manage to get any AA settings to work via NV control panel or using nv inspector.
Thanks in advance if you can help.
Hi Googler, “override” doesn’t work in Crysis, and neither does “enhance” if you’re using DX10 (the latter seems to be a driver bug).
Also the old modes like 2×2 are DX9 only, and probably won’t work in Crysis DX9 even with “enhance”.
To enable SSAA in Crysis, you need to use “application” and then set the AA in-game. Then use nVidia inspector to set an RGSS/SGSS mode. If you have an 8000/9000/200 part, you’ll also have to run Crysis under DX9 to make this work.
Which tool do you use to change lod bias with ssgs, nhancer does not work anymore?
Sebek, I didn’t adjust the LOD in this article. While nHancer doesn’t work at this time, I have no reason to suspect the functionality has been removed from the driver.
I think I read somewhere Nvidia said it has no plans to support LOD for SGSAA.
Also…
I think a nice and detailed AA guide would look rather good on Alienbabeltech.
ysondurr, a detailed AA guide has already been done. Check the links at the start of this article. It’s an ongoing job so it spans multiple articles.
I pay attention to this site, so I know about those articles.
Want to see more indepth, because I know you have it in you
There’s like one or two site on the whole internet for image aficionados and they are all on freaking German!