Explain why some games can not use Antialiasing?

[F1refly]

I wanted to know why some games, GTA 4 in particular, cannot use any AA whatsoever.
In GTA 4, i'm playing at 1900x1080 and the jaggies are just terrible still. now some games at that resolution are not so bad, but how come there is no way to force the NV gpu to at least fake some AA?

I hear it has something to do with how they render? explain and why would this render method have any advantage?

 

[pcslookout]

Originally posted by: F1refly
I wanted to know why some games, GTA 4 in particular, cannot use any AA whatsoever.
In GTA 4, i'm playing at 1900x1080 and the jaggies are just terrible still. now some games at that resolution are not so bad, but how come there is no way to force the NV gpu to at least fake some AA?

I hear it has something to do with how they render? explain and why would this render method have any advantage?

I would like to know this as well because Bioshock has the same problem.

 

[shortylickens]

Probably ask in the Video section.

 

[Kalmah]

I wonder what the purpose is using a method that doesn't support aa vs one that does? Maybe it has to do with being a console port as well?

 

[Udgnim]

in GTA 4's case, I've read it has to do with the engine using deferred lighting and AA being possible in DX10 but not in DX9. since GTA 4 is only DX9, AA is not possible

 

[reallyscrued]

Any games on the UT3 engine uses differed shadowing and doesn't support a lot of AA methods within the game engine. It kinda blows too cuz everything on UT3 based games are bumpmapped to hell so there are jaggies everywhere.

With the new Cats 9.7 in XP, I've been able to use AA on UT3 games. You could always do it with DX10 though in Vista/7, not sure why.

GTA IV is just a very badly ported game.

 

[mwmorph]

Deferred lighting simplifies lighting. It reduces GPU workload in complex lighting scenes. Basically what it does is takes small portions and then stitches them together. The problem with it is that with AA, it no longer works correctly because the lighting and geometry stages are separated. The only way to do it correctly is to force Edge detect AA on the final image itself rather than Box AA like you usually have.

 

[F1refly]

But it is impossible to fake any kind of AA in games like GTA 4 right? or is there some method?
i tried in NV console to force it but no avail. Pressing "P" makes everything fuzzy and i dont really think it helps Aliasing much, not enough to be worth it anyway.

strange cause GTA 4 is actually pretty beutiful game in terms of details and realism of city life, I used the First person Mod and just walking around the city, especially at night looks pretty amazing overall but those stupid jagged lines everywhere ruins alot of it.
but using alot of mods and simply walking along the sidewalks in first person view, as mundane as it sounds, to my suprise is actually the most authentic feeling "simulation" experience i ever had in a game....but those d*** jaggies.
I can only imagine how great it could've been if made specifically for PC.

 

[zerocool84]

I use nhancer.com and use that for UT3 engine games that even won't work in the NV control panel and using this makes it work. Search around for a way to get AA to work in your game to play around with the settings.

 

[mwmorph]

Originally posted by: F1refly
But it is impossible to fake any kind of AA in games like GTA 4 right? or is there some method?
i tried in NV console to force it but no avail. Pressing "P" makes everything fuzzy and i dont really think it helps Aliasing much, not enough to be worth it anyway.

strange cause GTA 4 is actually pretty beutiful game in terms of details and realism of city life, I used the First person Mod and just walking around the city, especially at night looks pretty amazing overall but those stupid jagged lines everywhere ruins alot of it.
but using alot of mods and simply walking along the sidewalks in first person view, as mundane as it sounds, to my suprise is actually the most authentic feeling "simulation" experience i ever had in a game....but those d*** jaggies.
I can only imagine how great it could've been if made specifically for PC.

I'm am not familiar with the GTA 4 engine, but technically SSAA and Edge Detect AA should work. Supersampling is the brute force, just apply the algorithim to everything AA and Edge detect is still more processing intensive than MSAA but should look nicer than SSAA.

Edge detect AA was introduced on the ATI Radeon 2900 series and I know ATI cards after that support it, but I'm not sure if Nvidia does. I do know Edge detect murders your FPS though, since the options are 12x and 24x edge detect (corresponding to 4x and 8x MSAA), but it should give about the best quality you can expect AA wise.

 

[F1refly]

Originally posted by: mwmorph

Originally posted by: F1refly
But it is impossible to fake any kind of AA in games like GTA 4 right? or is there some method?
i tried in NV console to force it but no avail. Pressing "P" makes everything fuzzy and i dont really think it helps Aliasing much, not enough to be worth it anyway.

strange cause GTA 4 is actually pretty beutiful game in terms of details and realism of city life, I used the First person Mod and just walking around the city, especially at night looks pretty amazing overall but those stupid jagged lines everywhere ruins alot of it.
but using alot of mods and simply walking along the sidewalks in first person view, as mundane as it sounds, to my suprise is actually the most authentic feeling "simulation" experience i ever had in a game....but those d*** jaggies.
I can only imagine how great it could've been if made specifically for PC.

I'm am not familiar with the GTA 4 engine, but technically SSAA and Edge Detect AA should work. Supersampling is the brute force, just apply the algorithim to everything AA and Edge detect is still more processing intensive than MSAA but should look nicer than SSAA.

Edge detect AA was introduced on the ATI Radeon 2900 series and I know ATI cards after that support it, but I'm not sure if Nvidia does. I do know Edge detect murders your FPS though, since the options are 12x and 24x edge detect (corresponding to 4x and 8x MSAA), but it should give about the best quality you can expect AA wise.

forcing super sampling or forcing AA does not work in games like gta 4. there is no way to force it and i'd like to know why. but supposedly, theres a mod that does AA but its very buggy and requires windowed mode and other specifics

 

[mwmorph]

Originally posted by: F1refly

Originally posted by: mwmorph

Originally posted by: F1refly
But it is impossible to fake any kind of AA in games like GTA 4 right? or is there some method?
i tried in NV console to force it but no avail. Pressing "P" makes everything fuzzy and i dont really think it helps Aliasing much, not enough to be worth it anyway.

strange cause GTA 4 is actually pretty beutiful game in terms of details and realism of city life, I used the First person Mod and just walking around the city, especially at night looks pretty amazing overall but those stupid jagged lines everywhere ruins alot of it.
but using alot of mods and simply walking along the sidewalks in first person view, as mundane as it sounds, to my suprise is actually the most authentic feeling "simulation" experience i ever had in a game....but those d*** jaggies.
I can only imagine how great it could've been if made specifically for PC.

I'm am not familiar with the GTA 4 engine, but technically SSAA and Edge Detect AA should work. Supersampling is the brute force, just apply the algorithim to everything AA and Edge detect is still more processing intensive than MSAA but should look nicer than SSAA.

Edge detect AA was introduced on the ATI Radeon 2900 series and I know ATI cards after that support it, but I'm not sure if Nvidia does. I do know Edge detect murders your FPS though, since the options are 12x and 24x edge detect (corresponding to 4x and 8x MSAA), but it should give about the best quality you can expect AA wise.

forcing super sampling or forcing AA does not work in games like gta 4. there is no way to force it and i'd like to know why. but supposedly, theres a mod that does AA but its very buggy and requires windowed mode and other specifics

I have an ATI card so i can't personally test it. I know a few driver releases back, turning on catalyst AI to advanced and forcing any AA type (box, narrow, wide or edge) gives me working AA in UE3 games (I refuse to play GTA 4 on the principle that it's the worst programmed pc game in a long time and I will not support that).

 

[Zenoth]

It's usually caused by the way the game's engine works with reducing jaggedness, take S.T.A.L.K.E.R. and its X-Ray engine for instance, it's using a method called deferred shading (paragraph 9.5), which is roughly doing the same as anti-aliasing. It's a similar with games running on the Unreal Engine 3 (more limited in DX9, supposedly works in DX10). And there are games in which it never works properly whatever you attempt, for instance blurring the UI as well as the polygons, that's the case with Warhammer 40,000 (actual A-A does work, but also blurs the UI, making it difficult to read anything especially at high resolutions).

 

[Fox5]

AA is a post processing technique, so I guess whatever post-process techniques the game uses interfere with polygon edge detection. I'd imagine super sampling or a blur filter (combined with a sharpening filter to somewhat counteract the effects) could be done.

 

[BFG10K]

Originally posted by: mwmorph

I'm am not familiar with the GTA 4 engine, but technically SSAA and Edge Detect AA should work.

No, they won?t. Super-sampling doesn?t automatically work because it can still anti-alias the wrong buffer(s), or the results of the anti-aliasing are destroyed from the deferred renderer.

Basically in order for super-sampling or edge detect to work, MSAA has to work. And to do that, either the game or the driver has to know how to apply it properly.

Now, in most games both vendors have implemented driver workarounds (e.g. UT3 games) but GTA4 doesn?t have anything like that yet.

It may be possible to write a custom shader that performs an edge-detect post-filter, and inject this into each frame the game renders. But neither IHV is doing anything like this to my knowledge.

I know a few driver releases back, turning on catalyst AI to advanced and forcing any AA type (box, narrow, wide or edge) gives me working AA in UE3 games (I refuse to play GTA 4 on the principle that it's the worst programmed pc game in a long time and I will not support that).

Again, in order for that to work, MSAA has to work. And ATi did just that after they followed nVidia?s lead and allowed their driver to force AA in those games.

 

[flexy]

Technically it WOULD work if it would use DX9.0c or DX10.

With those DX versions (correct me if i am wrong!) its possible to use AA together with deferred shading.

Its basically lazyness on the developer's side since they kept with DX9 and did not improve shaders/add shaders for more advanced DirectX.
Basically, it IS possible but would need rewritten/additional shaders beyond DX9.

 

[zerocool84]

I"m on Vista and can't get AA in any UT3 Engine game to work. Not manually in the Nvidia control panel.

 

[vj8usa]

You could downsample it from a higher resolution, but the performance hit and VRAM usage will be huge.
http://www.pcgameshardware.com...ith-Downsampling/News/

 

[imaheadcase]

I play at 1920x1200 so don't notice jaggies anyways so don't care for AA

 

[BFG10K]

Originally posted by: zerocool84

I"m on Vista and can't get AA in any UT3 Engine game to work. Not manually in the Nvidia control panel.

Something is wrong because that isn?t normal behavior. Are you on the 19x.xx drivers? If you are, they have issues with applying profiles so roll back to the 186.xx drivers.

Originally posted by: imaheadcase
I play at 1920x1200 so don't notice jaggies anyways so don't care for AA

For me personally, I can easily spot the difference between 2xAA and 4xAA, even at 2560x1600.

 

[zerocool84]

Originally posted by: BFG10K

Originally posted by: zerocool84

I"m on Vista and can't get AA in any UT3 Engine game to work. Not manually in the Nvidia control panel.

Something is wrong because that isn?t normal behavior. Are you on the 19x.xx drivers? If you are, they have issues with applying profiles so roll back to the 186.xx drivers.

Ahh ok cus I play UT3 a lot and am on the latest drivers. Thanks BFG.