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by h4ch1 82 days ago
No, it's using the newish SSGI and TRAA webgpu nodes. The three team has been making great progress with SSGI and webgpu in general and i'd recommend checking it out if you're interested.

There's also a denoise node in three (not used in this example), but SSGI still looks kinda blurry.

Work though is still going on: https://github.com/mrdoob/three.js/issues/31892
1 comments
Sharlin 82 days ago
Jesus Christ, trying to figure out what TRAA is (presumably an anti-aliasing algorithm) and how it works and it's entirely impossible to google.
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h4ch1 82 days ago
TRAA basically works by using a history buffer, for example using the last couple of frames, all jittered a little bit to compute the pixel. There's still ghosting and smearing that can happen though because of this technique, so you have methods to counteract like subpixel correction where u increase temporal alpha when velocity is subpixel, but that can introduce some artifacts as well.

There's also SMAA T2x which the pmndrs team is planning on integrating into their postprocessing package[0]. This cryengine3 slideshow gives a nice overview of antialiasing methods if you're interested: http://iryoku.com/aacourse/downloads/13-Anti-Aliasing-Method...

[0] https://github.com/pmndrs/postprocessing

This paper also provides a decent overview of TRAA: https://fileadmin.cs.lth.se/cs/Education/EDAN35/projects/17C...

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menno-sh 82 days ago
Temporal reprojection anti aliasing :)

https://www.threejs-blocks.com/docs/traaHD

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Sharlin 82 days ago
The only thing even remotely related to graphics I found was references to "TrAA" in forum posts from 2006 (yeah) where I believe they referred to NVIDIA "Transparency AA" or something like that. "TRAA", "TRAA meaning", "TRAA graphics", "TRAA 3D" all gave fully irrelevant results :D
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jldugger 82 days ago
If you make the assumption that "AA" is some form of antialiasing, it's not too bad: first scholar[1] hit expands the acronym to Temporal Reprojection Anti-Aliasing

    [1]: https://scholar.google.com/scholar?hl=en&as_sdt=0%2C5&q=traa+anti+aliasing&btnG=
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Sharlin 81 days ago
Yeah, should've tried with "antialiasing". Still, astonishingly obscure given that it's not even a new thing anymore and apparently implemented in UE4 and others.
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nilkn 82 days ago
The free Google AI mode got it for me on the first try by just pasting in the comment and asking what TRAA was in that context.
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