Antialiasing vs downsampling -- which is preferred?

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Coldblackice

[H]ard|Gawd
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Between using antialiasing vs. downsampling a higher resolution, which route would maximize FPS and quality? Which do you personally use?

In other words, would you be better off running at 1080p with AA ramped up, or 1440p downsampled to 1080p with no AA?
 
If you're concerned with FPS, you should really leave AA off completely. Don't have any references in front of me, but I always thought downsampling was equivalent (or worse) performance hit to Supersampling (SSAA). It seems as much, the many times I've used it (and like SSAA should be reserved for users with Crossfire or better).

For performance without sacrificing too much quality, one should be using the more efficient but blur-happy FXAA if the game allows.
 
It's a mix of settings that get you the desired effect. Personally I like to turn a few settings down a notch until I can enable downsampling at my optimal frame rate. I don't like FXAA in fast paced games like first person shooters because it smears the image like mayonnaise; when you spin around for example. If it's an older title then I turn everything to the max and 4K downsample it. In Project Cars I can SMAA 2TX and enable 2X downsample if I turn the grass and motion blur down a notch. Some games if I enable downsampling the game starts hitching and hiccuping.

Basically you're going to have to find out what you can live without when using downsampling.
 
In HardOCP's original review of the GTX 980, DSR was described as a downsample filter with a 13-tap Guassian blur added, that should be "another way to achieve the same effect, full-scene, with potentially less impact on performance" as Supersampling AA.

They talked about doing a separate article on DSR but that hasn't appeared yet, unless I missed it.

Also, there's this quote from a downsampling guide on Guru3D (note that "full scene antialiasing", or FSAA, is the same thing as supersampling, or SSAA):

"How much performance will I lose when using downsampling?
This will depend entirely on the game in question. In most cases the performance impact will be proportional to the increase in resolution or total number of pixels. However, graphics card memory may also need to be considered. Overall, this method should provide image quality comparable to full scene antialiasing but with far less compatibility issues and in many cases higher performance. The downside is that in some cases game menus may become harder to read. Fortunately, many games - for e.g. Arma 2 - allow you to increase the size of the UI and in some - for e.g. Need for Speed: The Run - it will auto-adjust."
 
I play SP mostly.

played spec ops the line awhile ago.

Best for me was DSR, Vsync, Framerate limiter and high quality setting in nvidia control panel.
 
I never get this argument if you are really going to render at 2560x1440 why not just get a monitor of that resolution and push it back far enough that you cannot make out the pixels and let your eyes do the natural "AA". All these blur techniques will hopefully be destroyed by high resolution and any space for them on GPUs will be freed up to be applied to real performance. AA is suppose to work because it allows you to render at a lower resolution and make it less apparent. Going the opposite way is mind numbing stupid to me. If AA is not faster FPS wise than downsampling then holy heck get rid of AA.
 
ran DA:I at 3200*1800 & 0xAA via AMD VSR on a 1080 monitor

compared against 1920*1080 & 2xAA

I'd take the 1080 2xAA

jaggies were more noticeable at 3200*1800 0xAA than 1080 2xAA and it's too much of a performance to run 3200*1800 whether 0xAA or 2xAA with a single R9 290
 
Depends on how well the game runs but I use gedosato on anything that i can get to run at 60fps or more. I find it better then any form of AA.

Downsampling has the advantage of increasing texture sharpness almost like installing a texture pack in some cases while also decreasing aliasing on top of it. Light forms of AA like fxaa or smaa distort and blur textures, while other forms of AA don't get rid of all of the aliasing in a image and don't support every game.

Mafia 2 with fxaa
Mafia 2 with fxaa

mafia 2 3840x2160 @ 1080
Mafia 2 3840x2160 @ 1080
 
One advantage about downsampling is that you can do it for ANY game, whether it supports any form of AA or not. A disadvantage for downsampling is that game UIs can get really small, to the point that you can't read them, and placement of UI elements may get funky, because the game has no way of knowing it's really showing on a much smaller display and you might not have any feasible method of customizing the UI.
 
I grew up on monochrome and CGA. "Jaggies" don't bother me at all. I would either go to a higher resolution or crank up other options like viewing distance, geometry detail, and so on.
 
Neither, AA is overrated at higher resolutions, makes the games look to "soft and fuzzy" and I would rather have framerate. Anistrophic filtering and draw distance is much more visually important
 
Arct1c0n said:
Neither, AA is overrated at higher resolutions, makes the games look to "soft and fuzzy" and I would rather have framerate. Anistrophic filtering and draw distance is much more visually important
Click to expand...

What kind of AA are you using? When I use AA it is not "soft and fuzzy"
 
Arct1c0n said:
Neither, AA is overrated at higher resolutions, makes the games look to "soft and fuzzy" and I would rather have framerate. Anistrophic filtering and draw distance is much more visually important
Click to expand...

The soft and fuzzy look is from the newer AA techniques that have gotten popular, like FXAA. They look like complete shit IMO, but are basically "free" AA in terms of performance cost. The AA used in older games had a big performance impact but looked much better.
 
rudy said:
I never get this argument if you are really going to render at 2560x1440 why not just get a monitor of that resolution and push it back far enough that you cannot make out the pixels and let your eyes do the natural "AA"...............
Click to expand...

there's a very simple answer to that question....refresh rate.

try to find an inexpensive (~$250 - $300) monitor that does 120hz+ at over 1080p.

i'll take a 120hz+ refresh rate for maximum smoothness over higher pixel count any day of the week....but that's just my personal preference.
 
xXaNaXx said:
there's a very simple answer to that question....refresh rate.

try to find an inexpensive (~$250 - $300) monitor that does 120hz+ at over 1080p.

i'll take a 120hz+ refresh rate for maximum smoothness over higher pixel count any day of the week....but that's just my personal preference.
Click to expand...

The same. I had a Korean 1440p + 60HZ before my current monitor and while Gsync is legit and a difference maker, 144hz is fucking magical. I have used 120hz but there is something about that 144 that just makes games like BF4/CSGO on a whole new level.

Framerate >> Resolutions.
 
naticus said:
The same. I had a Korean 1440p + 60HZ before my current monitor and while Gsync is legit and a difference maker, 144hz is fucking magical. I have used 120hz but there is something about that 144 that just makes games like BF4/CSGO on a whole new level.

Framerate >> Resolutions.
Click to expand...

My ASUS 144hz with the mod for motion blur and what not makes playing FPS fantastic. Going back to my U2711 it looks so damn choppy.
 
I'm a new downsampling convert. IMO, it achieves similar IQ as AA, improves texture sharpness, with less performance cost than AA. I'll use it just about everywhere as long as I can still read/see the UI elements. So IMO, I'd rather use 1.5x or 2.0x downsampling, than enable any form of AA.
 
Downsampling is anti-aliasing. Do you mean multisample anti-aliasing?

If so, you should use MSAA when performance is at a premium and add downsampling to the mix (in tandem with MSAA) when not.

rudy said:
I never get this argument if you are really going to render at 2560x1440 why not just get a monitor of that resolution and push it back far enough that you cannot make out the pixels and let your eyes do the natural "AA".
Click to expand...
Because monitors are not free and desks are rarely deep enough.
 
yourgrandma said:
Depends on how well the game runs but I use gedosato on anything that i can get to run at 60fps or more. I find it better then any form of AA.

Downsampling has the advantage of increasing texture sharpness almost like installing a texture pack in some cases while also decreasing aliasing on top of it. Light forms of AA like fxaa or smaa distort and blur textures, while other forms of AA don't get rid of all of the aliasing in a image and don't support every game.

Mafia 2 with fxaa
Mafia 2 with fxaa

mafia 2 3840x2160 @ 1080
Mafia 2 3840x2160 @ 1080
Click to expand...

Downsampling way better. FXAA makes it look washed out, or is it the downsampling that makes it sharper?
 
In my own tests, downsampling only notably beats SMAA in general anti-aliasing quality, when the resolution you are downsampling from is double your monitor's native resolution. So the most common would be 4K downsampled to 1080p.

If you can do that and still achieve acceptable framerates, great. However, most modern games require $300+ GPUs to do that.

If not, SMAA (or even FXAA set to edge detect and a slight shaprness boost), will give you similar anti-aliasing quality, have way better framerate potential, and still maintain sharpness.
 
using Dragon Age: Inquisition and AMD VSR

comparing aliasing at 1080 4xMSAA, 1080 0xMSAA, and 3200*1800 0xMSAA. Post Processing AA in DA:I is disabled.

1080 4xMSAA

HLC2G7g.png


1080 0xMSAA

ZBfSbFT.png


3200*1800 0xMSAA

OCPT65H.png


1080 4xMSAA

OZpmjXP.png


1080 0xMSAA

0QZdnNG.png


3200*1800 0xMSAA

C79BCbx.png
 
Ignoring aliasing the textures look notably sharper in those images with downsampling.
 
Does BF4 do this or something else? I know there is a resolution scale slider in the game menu. I only have a 2500k and a stock 290. So i can't push it and still get 100+ fps.
 
Why is this a VS thread? Downsampling and AA are not mutually exclusive. Well, if you are hellbent on using MSAA then yeah the the performance cost is too much but the beauty of downsampling is that it makes post-processing AA look amazing. Hell, even FXAA looks great because the blurring effect it causes are putted on the high resolution render before downsampling, and since the downsampling "shrinks" the image the blur is reduced. Downsample from very high resolution if you have the horsepower and the FXAA blur practically disappears.

With 1080p screen downsampling just from 1440p with SMAA or mild FXAA on top and the picture looks better than MSAA can ever hope to be, completely free of jaggies even in motion and thanks to higher resolution render it manages to dig out details from longer distance compated to native 1080p rendering. Only downside is the picture is more susceptible to moire noise in some patterns, but thats with GPU downsampling. DSR with its gaussian filter is less susceptible.
 
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yourgrandma said:
Ignoring aliasing the textures look notably sharper in those images with downsampling.
Click to expand...

In my experience, the improvement to textures is subtle. and it costs you double your screen resolution, to really even get the texture benefit, if there at all (it depends upon the game)

You can get the same benefit from using sweetfx or something like that, to do a small sharpness boost. (If you really spend some time, you can completely redo the color curves and pull out details by regrading darker colors). Heck, you can do SMAA, a sharpness boost, contrast boost, color tweaks, added bloom effects, etc------and still have a much higher framerate potential, than downsampling alone. There's a lot of mileage in post processing shaders which should be explored before downsamplling. Once you have your shaders setup, then downsample as much as you can, if you can.

Downsampling is nice if you have the horsepower. At double screen resolution or higher, nothing else will removing aliasing as well, on small details, distant details, and alpha assets.

But, I think downsampling is getting way too much emphasis, for such small, highly specific benefits. People who don't have the horsepower shouldn't feel like they are missing out on something major and trying to rationalize a $400 GPU purchase.
 
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AA over DSR any day of the week. I don't like the bur effect at all.
If you are downsampling then you can sometimes get better results than using AA (e.g., UE3 engine games that do not apply AA to certain components of the scene).
 
Setting DSR Gaussian blur at 15% or so should eliminate any DSR bluring as a result of rendering the game at a non whole number ratio resolution. You wouldn't need to if it was say rendering 4k DSR on a 1080p screen.
 
chameleoneel said:
In my experience, the improvement to textures is subtle. and it costs you double your screen resolution, to really even get the texture benefit, if there at all (it depends upon the game)

You can get the same benefit from using sweetfx or something like that, to do a small sharpness boost. (If you really spend some time, you can completely redo the color curves and pull out details by regrading darker colors). Heck, you can do SMAA, a sharpness boost, contrast boost, color tweaks, added bloom effects, etc------and still have a much higher framerate potential, than downsampling alone. There's a lot of mileage in post processing shaders which should be explored before downsamplling. Once you have your shaders setup, then downsample as much as you can, if you can.

Downsampling is nice if you have the horsepower. At double screen resolution or higher, nothing else will removing aliasing as well, on small details, distant details, and alpha assets.

But, I think downsampling is getting way too much emphasis, for such small, highly specific benefits. People who don't have the horsepower shouldn't feel like they are missing out on something major and trying to rationalize a $400 GPU purchase.
Click to expand...

IMO the sharpen effect its complete ass, it distorts textures and creates ghost outlines on everything. It's nothing compared to what you get from true downsampling.

Even with a 3gb card i have no problems downsampling most older or even recent console ports at 4k. It's only when you're downsampling new games you need top end hardware to do it with. I think screen size makes a big difference if whether or not you find it worth as i use a 27" 1080p screen.
 
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