Understanding Anti-Aliasing

[Kynes]

Scoobes said:

Kynes said:

Scoobes said:
Sooo... anyone know why FXAA causes texture blurring?

Because it's a blur filter. A clever implementation of a blur filter, but it does not calculate more geometry/color samples, as other AA methods do. The good thing about FXAA and other shader AA methods is that they have a very low performance hit, and they also help with specular/shader aliasing, but they fail miserably with subpixel geometry and you can have texture blurring. There is an evolution of FXAA called SMAA that provides better image quality: http://www.iryoku.com/smaa/

Thanks for the info. SMAA has more of a performance penalty though doesn't it?

SMAA has 3 modes: 1x, 2Tx and 4x. SMAA 1x should be almost as fast as FXAA, on a low performance graphics card FXAA penalty should be less than 5%, SMAA 1x ~7%. SMAA 2Tx has a bit higher performance hit, ~10%. SMAA 4x has a rather big performance hit, between 2x MSAA and 4x MSAA, but with a much higher image quality IMO.

Take a look at this Crysis 3 review, where they compare the different AA options in image quality and performance: http://www.hardocp.com/article/2013/03/12/crysis_3_video_card_performance_iq_review/