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So I have this problem with FXAA. The lines I draw using GL_LINES look, well, not really anti-aliased after applying FXAA as a post-process filter, they just look blurred. So my Question basically is - is this the espected bahaviour of FXAA with GL_LINES? The shader code I'm using is nothing special (See here)

This is how the FXAA output looks:

fxaa

And here is the (standard 4x) MSAA:

enter image description here

LJᛃ
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Dänu
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    [The image](http://www.ozone3d.net/public/jegx/201104/fxaa_demo_05.jpg) in the article you posted also looks similar by the way and there's mention of an improved version in the comments. – Marco A. Dec 01 '16 at 14:07
  • @MarcoA. Yes, that is, in fact, why I suspect it to be the expected result. As for the improved version mentioned in the comment - I'm aware fo V2 and V3 of FXAA, however I would like to keep using the simplest version possible, which is V2 (http://www.phoronix.com/scan.php?page=article&item=nvidia_fxaa&num=1). – Dänu Dec 01 '16 at 14:18

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No matter the fact that it has "antialiasing" in its name, FXAA is not really antialiasing. "Real" antialiasing techniques involve taking multiple samples of the signal; FXAA, as a post-processing technique cannot do that.

At the end of the day, it is nothing more than a smart blur filter. So while there may be variations of it that can handle lines better, it's still just a blur filter.

Nicol Bolas
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  • Thank you, that's exactly the same conclusion that I reached and I wanted get a second opinion on. I'm now tweaking it a bit to get better results. The changes that Lottes introduced in 3.11 are quite helpful (https://gist.github.com/bkaradzic/6011431) – Dänu Dec 02 '16 at 09:43