Any reason not to combine Control Panel FXAA with in-game Anti-Aliasing settings?

In my own tests it seems like FXAA is often the only control panel AA settings that actually works in modern games when enabled (there are the multisample/supersample options/transparency, but when I enable them for most games with "enhance the application setting" I don't see a perf decrease and don't notice any difference in practice so I "assume" they aren't supported in that given title -- of course I've not tested "every game", but that's what I've seen thus far -- not sure what determines what titles are supported for the non-FXAA control panel AA settings at this point).

So far I've seen what I would consider to be pretty good results combining the in-game post AA (TAA/SMAA) with control panel FXAA then using something like 25% on the new control panel sharpening (w/ default grain rejection of 17%).

My question then is, any good reasons you wouldn't do this? I understand FXAA (especially in conjunction with other in-game post AA post settings) can cause some "softness" to the image/make text a bit blurrier than it otherwise would be when forced from the control panel (since it will effect everything in the game) and there's a really small GPU perf impact, but anything beyond that? Could it cause issues with the game's own AA for example?

Alternatively are there some games where the FXAA won't actually work/games that aren't supported or does it basically work for any game? I've read in another thread that the FXAA will go "on top" of any ingame AA rather than replacing it which is great.

Thanks for your time, I appreciate it!

 

no reason not to use it if you like what it looks like

 

@Xul Aethyr Thanks, yeah seems nice to me so far, but I wasn't sure if it could cause some issues in certain games or degrade visual quality in some way I hadn't observed yet.

 

FXAA is something that you can leave on all the time without worry in my experience. Why not have it enabled in the CP and game settings, can't hurt.

 

@jbscotchman Thanks! That's helpful -- do you happen to know if in addition to turning FXAA ON in the control panel, I also need to set the "antialiasing - Mode" to "Enhance the application setting"? Or, can I just leave that alone -- it looks to me like the whole "Antialiasing mode -> Enhance/Override the application setting" applies to the 2x-8x antialiasing setting and maybe the antialiasing transparency settings, but my understanding is that if all you want to do is turn the control panel FXAA ON all you need to do is enable it then you can leave the Antialiasing - Mode just on "application controlled" without issue/the control panel FXAA will still be tacked onto whatever AA the game itself is doing. Have I got that correct? Or is the FXAA "strength" tied to the "antialiasing - setting" value? (2x-8x) -- Thanks,

 

You are correct, most games can't have forced AA. I doesn't work in DX10+ without the game itself already having MSAA.

Using FXAA on top of TAA can help out with some rough edges it misses. But you have some downsides as it affects the UI and can make the image even blurrier than with just TAA. Sharpening can help but ideally, it would be better if you used DSR as well as in game TAA and Driver FXAA. Some games have used this approach as well. Such as RE-Engine games, Crysis 2, Horizon Zero Dawn I think uses it on PS4 Pro to help clean up a pass of it's checkerboarding. Though the Nvidia driver version is tuned better to my eyes than most game implementations and gets more edges. Same with Reshade. In RE-Engine for example the FXAA settings they use do a pretty mediocre job compared to custom settings with Reshade.
https://www.screenshotcomparison.com/comparison.php?id=58

You don't need to enable "Enhance" that's only if the game has MSAA and you are trying to add TrSSAA or SGSSAA on top. It will not do anything with FXAA. The FXAA is just a toggle on and off. And the only other setting that affects is the "Nvidia Predefined FXAA usage" setting.
You can just turn FXAA on and leave it on. However some games have flags on the profile to prevent driver FXAA from working. (As mentioned above.)

 

@MrBonk Thanks for explaining all of that, that's really helpful! Yeah, the softening of the UI elements is unfortunate -- ideally most games that already have FXAA as an option (such as Overwatch) would instead take the Rage 2/Red Dead 2 approach where the let you have multiple forms of AA active in-game at once (so, TAA + FXAA for example in those games cases). That way you avoid the UI softening issue. For example, in Overwatch it would be nice to able to both enable SMAA + FXAA in-game given both are options there, but alas no such option is present it's one or the other so the only work around is in-game SMAA + control panel FXAA which will have the UI softening. Thanks for the screenshot comparison there by the way I can see what you mean.

 

If you don't mind blurred out text leave it on.

FXAA is applied to the entire screen, even in the menus.

For me personally it's an absolute last resort, which thankfully is rarely needed.

 

Combining SMAA and FXAA is stupid. You have two post-process AAs fighting each other. There is a reason why combined AA methods exist, as they work together, not against each other.
In other words, manually combining TAA and SMAA and using SMAA T2x are two different things.

 

For me atleast I found SMAA is great in reshade only if it has access to depth buffer.
If any of these anti aliasing solutions dont have access to it, they probably cant tell the difference between UI and game thus blurring everything, that is usually not an improvement
and takes a lot of tinkering to get right.
Good start is to just run the game in highest resolution possible without perf issues, then usually highest quality ingame TAA combined with good sharpening filter, and later maybe FXAA/SMAA/any postprocessing AA etc that doesnt mess up UI much.

 

@Terepin Thanks for your comment, this is the first I’ve heard of this and is sort of what I was primarily wondering about here.

Do you happen to have any further examples/articles/forum posts or some such that talk about this interference?

It’d be great to better understand how multiple AA methods can work against each other as you describe — so, I figured that the control panel FXAA wouldn’t hurt or decrease the quality of the in game setting as I’d expect it to run in a separate “pass” probably after the in game AA already ran, but I could be wrong about that — I had previously only thought the slight softening/text and UI blur were the only real downsides.

 

@S3r1ous Thanks for your comment that’s helpful to know — yeah, I had noticed that myself regarding the depth buffer and reshade. Initially I tried experimenting with it but found many/most games I tried didn’t have depth buffer access and in general I sort thought that at a glance the control panel FXAA did a roughly comparable job (my eyes aren’t maybe the most discerning though) so I gave up tinkering with it. Do you happen to know if the control panel FXAA runs later in the pipeline/process than the in game AA? @Terepin mentioned above that external AA can cause some issues with the internal AA (if I’m understanding correctly) but I wouldn’t expect that to be the case so long as the control panel FXAA ran in a separate pass later, no? Thanks,

 

Basically, each basic post-process AA covers the final image, but that image needs to be "raw". And since the only way to use both FXAA and SMAA is to inject one of them, you have one solution working on image that was already altered by previous one, which leads to problems. The only exception to this rule is SSAA, which can be combined with anything, since it only evenly increases resolution to the entire scene.
Now, I don't pretend I'm an AA genius or something, but AFAIK combined AA methods work in passes. In case of T2x it's like this: http://marcel-schindler.weebly.com/blog/anti-aliasing-smaa-t2x

 

@Terepin Thanks! That’s a really helpful explanation. Will look over that link for sure.

Forcing control panel FXAA would be fine/exempt from such conflict issues provided the game was using only MSAA though internally correct?

I would expect such AA interference like you’ve described would only occur if you’ve got two different post process AA’s acting on the image where since MSAA isn’t a post process method I’d think it could be combined with control panel FXAA pretty nicely, no -- given it only effects polygonal geometry and happens sooner in the pipeline/isn't applied over the final image like post AAs? (I could be wrong here ofc — technically the image isn’t “raw” if you’re using in-game MSAA I suppose).

Thanks again, I really appreciate your explaining that above, it’s helpful for me. Nice profile pic by the way.

 

MSAA also alters image.

 

Ah, gotcha thanks

 

@Terepin Oh, sorry, but I did think of one more question concerning Nvidia's Control Panel "Sharpen" feature -- could this also exhibit the same (or similar) "interference" if a game is already doing its own sharpening internally do you think?

So, for example, Crysis 3 is already using a Sharpen value of 0.25 internally for example if you view it using console commands. Another example might be games that have the AMD CAS Sharpen option available in their own in-game menu (like Rage 2) or games like DOOM Eternal which have a sharpening slider. Still further games "may" be doing a some amount of Sharpening just without telling you (Crysis 3 doesn't tell you, you can only see the value its using with console commands for example and I wonder other games may be taking this approach as well, especially in conjunction with their TAA setting perhaps, but I'm speculating).

Do you think there would be problems then using the Nvidia Sharpening feature in conjunction with a game's own sharpening? I would imagine there would be personally -- so, I would think you'd want to use one or the other I mean (either use the in-game sharpening OR the Nvidia control panel sharpening, but not both -- probably the in-game since it would likley avoid sharpening the UI elements, etc perhaps). Thanks for your time, I'm sorry to spam you.

 

When it comes to blurry AA, I would rather run at lower res with better quality AA using the GPU power saved.
Or use DSR (higher res rendering) alone as my AA method.
Then at least text wont be blurred.
I also dont like TAA (it looks like running at 1/2 res) but the latest DLSS will improve on it for those games that support it.

 

@Mufflore Thanks for your comment, that's one way to go, yup. I've only experimented a bit with DSR at this point given the cost it typically comes along with -- in games that have an especially "soft" looking TAA implementation, personally I find that the new CAS Sharpen filter (set to something more mild than the default 50% which I find to be a bit high -- Hardware Unboxed preferred to use it at ~20% in their tests on Youtube while certain games with internal sharpening like DOOM Eternal default to a value of 33% and Crysis 3 defaults to an internal value of 25%) can result in something that looks better overall to my eye. My primary concern would be sharpening externally though when its not clear if a game is already doing its own internal sharpening (not all games tell you they are like Crysis 3) which could cause some oversharpening artifacts or interference issues like I was asking Terepin about (at this point I'm just speculating though). Sadly even modern CAS Sharpen filters do seem to make any aliasing present look a bit worse to my eye, but I suppose it's a balancing act between aliasing and sharpness with TAA/FXAA/post AA filters so what can you do, eh?

 

Each game will need to be tested on its own merit.
Have a set AA procedure to try first and work from there.