[Digital Foundry] - Tech Focus: Anti-Aliasing - What Is It And Why Do We Need It
34 replies, posted
https://www.youtube.com/watch?v=NbrA4Nxd8Vo
Tbh hopefully in time we don't need anti-aliasing even in VR through resolution becoming good enough to kill it
Informative video, but I can't help but wonder if it was intentional or not that the text he adds on-screen suffers from aliasing.
(from 6:34)
https://files.facepunch.com/forum/upload/107272/186134a1-045c-4ec0-ba37-5ace558dd1de/image.png
I like Alex's videos but I wouldn't call them the best put together videos from DF.
SMAA or MSAA or bust. TAA and FXAA look like trash.
If I can't run a game with MSAA or SMAA I just don't use anti-aliasing. FXAA just makes everything blurry. I don't really notice much of a difference with TXAA but it makes games run like shit.
Neat video but I can't be the only one who never uses AA unless taking purpose screenshots.
A game in full motion makes it very hard to actually notice the aliasing, especially in faster paced games.
I play in generally 4k, so AA is really worthless unless you have like 32x AA or something
Some games have really bad jaggies and need AA to be on, whereas others look no different with it on or off
After 4K and VHFR, AA is waaaaay along the path to diminishing returns, much less 8K and FR above 300fps, which is something we'll be able to hit in a couple of years reliably, at least for PC.
It's hard to beat the quality from the other DF video makers. They consistently put out really high quality stuff.
FXAA is fine honestly on resolutions at 1080p or above, especially more modern implementations of it, where the blurring is practically negligible. SMAA is great and has been my favorite in terms of quality and performance ratio, but some modern games' rendering and shading methods causes a lot of shimmering and stuff that SMAA can't exactly capture. Though SMAA 1tx and above are nice implementations, shame it doesn't seem to pop up often in some games. Far Cry 5 in particular has a really nice TAA method, where there's no ghosting or any shimmering and performs roughly the same as SMAA while also looking better and nearly as sharp.
MSAA is not really practical anymore in comparison, especially since most modern games use deferred renderin, and most people might be better off just supersampling their internal res if they're looking for it. Good example of this is using the MSAA option in Battlefield 4 where not only does it significantly eat up more performance, it doesn't also manage to smooth out a lot of jagged edges due to Frostbite's rendering engine.
yeah i used to like it but now value performance and being able to identify things accurately over smoothed edges in games. in csgo / overwatch / fortnite especially i find it's really helpful to differentiate between things in front of you.
Is Alex an immigrant from North America just like John is? I can hear absolutely no clues of a German origin in his accent.
I wonder if TAA could use the pixel-moving type shit they use for "checkerboard upscaled 4k" on ps4, moving pixels along a motion vector to eliminate ghosting while providing the additional frame data
I'm not sure if I understand exactly what you mean, but that's essentially what TAA does. It takes only 1 sample per pixel, but every frame it changes the sampling location within the pixel. Then it does the temporal reprojection magic to combine the new frame with the previous frame so that you're effectively combining multiple samples for every pixel. That's why it's become so popular, it combines the strengths of supersampling (gets rid of aliasing EVERYWHERE, is an actual sampling-based method rather than an image based postprocess filter) and postprocess AA methods (super fast because you aren't actually gathering multiple samples per pixel).
right, didn't realize it was already being done like that; the instance of severe ghosting in DOOM looked almost like it was just being blended rather than reprojected
When you think about it, there's a ton of edge cases that can cause problems for techniques like TAA and have to be handled very carefully. For example, what do you do when a pixel was visible in the previous frame but gets occluded by an object moving in front of it in the new frame? Or vice-versa, a new pixel shows up in a position that was previously occluded. Then there's also the fact that the motion between frames doesn't happen in nice integer numbers of pixels so you're gonna introduce some extra blur. Then there's the fact that a pixel can change its appearance when looked at from different positions (e.g. specular reflections), which can lead to additional ghosting. + probably a lot more problems that I can't even imagine right now.
TAA reminds me a lot of motion prediction techniques used in video compression. The benefits can be immense, but it's almost impossible to avoid introducing at least some artifacts.
TAA is good only if you install reshade and sharpen the image, or if the game is good enough, DOOM, and offers an option for sharpening, with a slider for personal preference, then that's a good technique.
Honestly though, that said, Super Sample Anti Aliasing or bust.
I'm actually glad AA is becoming less costly to use. TAA and MSAA are pretty fucking good.
It makes foliage look like trash as a lot of alpha testing materials become blobby. I'd rather go with no AA than FXAA
This is actually mathematically wrong. Aliasing appears just on the edges of 3D objects and textures, but FXAA makes everything blurry. So, with with no AA you get better quality on ~99% of the whole image compared to FXAA.
...this is supposed to be a joke.
FXAA is fine if you're running high resolutions where the fine details can help. But 1080p it's definitely blurry.
I really like TAA, and some engines handle it amazingly well. That one edge case of the arm moving in DOOM is very much an edge case. TSSAA 8x looks like complete magic in DOOM and Wolfenstein. UE4 often has really good TAA. Same for Vermintide 2.
FXAA does suck.
But some implementations of TAA are far, far superior to no AA and SMAA; good examples are DOOM and The Division, those games are WAYYY better off for using it.
Do you think using the word "mathematically" gives your argument any extra validity or makes you sound smarter when you provide no actual math to back it up? Is your post a joke?
Aliasing appears in all sorts of places, maybe you should actually watch the video if you don't understand that. The edges of objects are just the most prominent example and that's what graphics hardware has been optimized for in the late 90s and 00s when MSAA was the gold standard.
It's also extremely unfair to call FXAA a blur filter because it's anything but. It's built on the idea of finding both the location and the orientation of edges within an image, then smoothing them out in an smart way that tries to preserve their shape and avoid adding unnecessary blur. Yes, it can introduce unwanted softness in some places, but that's just the unfortunate reality of trying to fix an image after the fact. It's like denoising a photo taken with a shitty camera in bad lighting. You can absolutely do it, but you're gonna end up losing some legitimate detail along the way.
I just turn AA off because it doesn't bother me that much and gives me a big FPs boost
Honestly, some MSAA implementations are so shit that FXAA just runs circles around it. Xcom 2 MSAA is just ludicrously expensive in performance and does literally NOTHING about half the objects anyway. FXAA cleans up the picture very well on 1440p. I'd prefer MSAA, i always will. but the MSAA is a joke in that game.
Meanwhile in Rise of the Tomb Raider, it's SSAA or bust. The SMAA at 1440p introduces so much foliage shimmering, it's a sick joke. FXAA here actually had a slight negative impact in a noticeable blur, but it also kills the shimmering.
Unfortunately, Post-processing AA is where we're at these days and TAA is the golden standard. SMAA often leaves me unimpressed and FXAA is always beter than nothing at all. But i just wish there was a way to get MSAA to work better with modern games, because bruteforcing SSAA via DSR or other means is just not possible for a lot of people...
In the end, FXAA is nothing to scoff at. I think some people need to get over themselves or start donating Titan XP's to everyone else. No one needs a shitty attitude. I'll take what i can get. as much as i can get in the AA department, but i'm never playing without it again.
Ah, cmon dude, chill and read more carefully next time.
https://i.imgur.com/RhdfWB1.png
Something something Only pretending...
Sorry dude, it looked like you were calling the post you were replying to a joke. It's legit hard to tell you're not serious cause I've heard very similar opinions expressed unironically by people who have no clue what they're talking about countless times.
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