Future of MSAA?

[Simon F]

With Quincunx it's impossible to display a white axis aligned rectangle on a black background without getting a one pixel wide grey halo around it. I just don't get how this is supposed to be a quality improvement.

Just a quick thought for you to mull over: What happens if you have to animate that rectangle and move it, say, 1/2 a pixel per frame....

 

[DegustatoR]

On some OpenGL games you can see more blur (mainly on in game text where it very much resembles 2xQ). Why there is a difference between D3D and OpenGL I do not know.

There was quite some number of ForceWare where blur filter was turned off for 2xQ and 4x9, so you didn't see any blur in these modes, but that makes their quality (and presumably speed too) completely equal to 2x and 4x respectively.

 

[Ostsol]

With Quincunx it's impossible to display a white axis aligned rectangle on a black background without getting a one pixel wide grey halo around it. I just don't get how this is supposed to be a quality improvement.

Just a quick thought for you to mull over: What happens if you have to animate that rectangle and move it, say, 1/2 a pixel per frame....

For the sake of discussion:



4x zoomed, rendered on a Radeon 9700 Pro with 4x FSAA. The box was rendered in ortho mode and shifted half a pixel to the right.

Of course, zeckensack's point was that you would never get a hard line (such as the top edge in my screenshot) with Quincunx, regardless of the positioning of the object.

 

[radar1200gs]

On some OpenGL games you can see more blur (mainly on in game text where it very much resembles 2xQ). Why there is a difference between D3D and OpenGL I do not know.

There was quite some number of ForceWare where blur filter was turned off for 2xQ and 4x9, so you didn't see any blur in these modes, but that makes their quality (and presumably speed too) completely equal to 2x and 4x respectively.

But that clearly isn't the case with the screenshots I've presented. For instance, take a look at the ammo/clip numbers on the farcry screen under magnification.

 

[DegustatoR]

But that clearly isn't the case with the screenshots I've presented. For instance, take a look at the ammo/clip numbers on the farcry screen under magnification.

What am i looking for? Blurriness on the HUD is caused by resampling HUD textures for this particular resolution.

As for blur filter, Xmas is right, it should definately be visible here on the trees leafs, but it don't. Slight overall blurriness of the shot can be caused by JPEG compression (yes, it's lossy even with 100% quality).

And, hey, since 4x9tap is 'unofficial' mode you can't be sure that RT is turning it on in the latest drivers NV could change the bihavior of this variable in the latest drivers. They've got rid of 6xS in their own CPL after all...

You really should make two shots from one view point, one with 4x, and one with 4x9tap, and then compare them.

But since blur filter can't be captured on the GF4Ti+ GPUs because it's done in the RAMDAC, while converting digital information to analogue the best way to compare 4x and 4x9tap on GF4Ti+ is to make a screenshot with 4x (or 4x9tap - they're identical on the screenshots anyway), set desktop resolution to the resolution you are using in the game, open up shot to fullscreen, force 4x9tap AA, launch the game in the same resolution, load the same view point and use Alt-Tab to switch between screenshot with 4x and the game scene with 4x9tap.

This way you'll see 'real' comparsion of 4x9tap with 4x AA.

 

[Basic]

Blurriness on the HUD is caused by resampling HUD textures for this particular resolution.

True.
More specifically; the digits come from a texture that is antialiased/blured in it's original format, and then magnified a factor two @1600x1200.

 

[no_way]

More specifically; the digits come from a texture that is antialiased/blured in it's original format, and then magnified a factor two @1600x1200.

OT, but: Where, oh where, has GL_SGIS_texture_filter4 gone, oh where oh where hed'd be ?

 

[Fox5]

I think Quincunx/4x9tap modes are fine. Whether people like them or not is gonna be subjective. They are compromise IQ improvement modes. Just like ATIS temporal AA. Each having their own side effect. Whether you like their compromises for performance is completely dependent upon user.

What's the side effect of temporal AA?(besides that it flickers at low fps?)

 

[ChrisRay]

I think Quincunx/4x9tap modes are fine. Whether people like them or not is gonna be subjective. They are compromise IQ improvement modes. Just like ATIS temporal AA. Each having their own side effect. Whether you like their compromises for performance is completely dependent upon user.

What's the side effect of temporal AA?(besides that it flickers at low fps?)

Well it forces vsync and shuts off when you go below a certain FPS threshold. As such I'd consider that a side effect. Making it a conditional function. Similar to Nvidias Quincunx. I was morely focusing on the vsync issue. But each has certain conditions to achieve its "supposively" higher IQ. As such I find them compromise IQ improvement modes.

 

[davepermen]

I think Quincunx/4x9tap modes are fine. Whether people like them or not is gonna be subjective. They are compromise IQ improvement modes. Just like ATIS temporal AA. Each having their own side effect. Whether you like their compromises for performance is completely dependent upon user.

What's the side effect of temporal AA?(besides that it flickers at low fps?)

it doesn't flicker. it means that you have 2x aa at low fps, and if fps get high enough, you get 4x fps. thats all.

 

[nobody]

I think Quincunx/4x9tap modes are fine. Whether people like them or not is gonna be subjective. They are compromise IQ improvement modes. Just like ATIS temporal AA. Each having their own side effect. Whether you like their compromises for performance is completely dependent upon user.

What's the side effect of temporal AA?(besides that it flickers at low fps?)

it doesn't flicker. it means that you have 2x aa at low fps, and if fps get high enough, you get 4x fps. thats all.

Oh yes, it does flicker. Because it means that you have alternating AA sample patterns each frame at high enough fps.

 

[DegustatoR]

it doesn't flicker. it means that you have 2x aa at low fps, and if fps get high enough, you get 4x fps. thats all.

It certainly does. And if you set 2x AA + Temporal and get high enough fps you're still getting 2x, but sample posions are different each frame. That's STILL 2x AA, with alternating sampling patterns.

 

[davepermen]

but at that high fps the frames get blended, resulting in one frame with 4x aa.

but of course, this doesn't mather to most of you, as you will still say "it does flicker!!".

 

[Simon F]

but at that high fps the frames get blended, resulting in one frame with 4x aa.

But how do they get blended? Is there some form of accumulation buffer?

 

[KimB]

but at that high fps the frames get blended, resulting in one frame with 4x aa.

Certainly not, because in typical game scenarios, there is motion on the screen. With a high degree of motion, there's every bit of aliasing visible with 2x AA as with 2x AA with temporal dithering. That is to say, no averaging is possible if the edge moves more than a pixel.

but of course, this doesn't mather to most of you, as you will still say "it does flicker!!".

And where this will be most visible is when, for example, there is an edge that is at just the wrong angle for one of the 2x AA patterns, producing lots of aliasing half of the time. With a full 4x pattern, this degree of aliasing would never be visible, any of the time.

 

[Fafalada]

But how do they get blended? Is there some form of accumulation buffer?

Retina-buffer(tm)?

 

[davepermen]

but at that high fps the frames get blended, resulting in one frame with 4x aa.

Certainly not, because in typical game scenarios, there is motion on the screen. With a high degree of motion, there's every bit of aliasing visible with 2x AA as with 2x AA with temporal dithering. That is to say, no averaging is possible if the edge moves more than a pixel.

but of course, this doesn't mather to most of you, as you will still say "it does flicker!!".

And where this will be most visible is when, for example, there is an edge that is at just the wrong angle for one of the 2x AA patterns, producing lots of aliasing half of the time. With a full 4x pattern, this degree of aliasing would never be visible, any of the time.

uhm, they are blended like any animation gets blended into a smooth image: by your eyes. or by the screen (espencially tft's with quite slow refresh timings).

you should understand that. thats .. very simple logic.

 

[KimB]

And you should understand that if there's motion, they can't be blended out.

 

[DegustatoR]

but at that high fps the frames get blended, resulting in one frame with 4x aa.

but of course, this doesn't mather to most of you, as you will still say "it does flicker!!".

This doesn't matter to me because at 4x TAA i see 4x + noises on the polygon edges, not some mysterious 8x AA. Can't help it, my eyes must be too old or something and doesn't support this "blending"

 

[nobody]

And you should understand that if there's motion, they can't be blended out.

That's the point.
Temporal AA may work only if there's no movement in a scene and your display device (CRT or TFT) refreshes very slow.