The future of anti aliasing

[CakeMonster]

Now that apparently MSAA modes are disappearing from games and being replaced by inferior postprocessing, where are we heading? Not just in the short term, but also in 5, 10 and 20 years - what will we see?

In recent years I had the feeling that performance was finally catching up allowing most people to use MSAA in common resolutions on relatively inexpensive gaming rigs. And just as that happens, it starts to disappear. To me that seems to defy all logic. (Yes I know that there are limitations, and that MSAA doesn't work on everything).

So where are we going? As pixel density increases there might be less need for it, but that would have to be quite a jump for it be completely unnecessary, probably far beyond what we will see any time soon. Right now, inferior postprocessing modes annoy me greatly and if this trend continues we will have to live with worse anti aliasing than we had just a couple of years ago until there is some new development. What will that be and how long will we have to live with the situation we are in right now?

 

[brandonb]

The problem is that developers are using deferred rendering. IE: Render to texture techniques. When you render to a texture the video card can't do its normal MSAA algorithms on the frame buffer (it can and is if its turned on) but all it's going to do is anti alias the edges of the big square that fills the screen that contains the texture that the game rendered to.

Why did games go to this method? Because it was attempting to reduce the number of pixels the game had to run shaders for. Deferred rendering basically means this: Render the entire scene and then only apply post effects to the nearest pixel in the scene rather than all pixels in the scene, even if they are obscured. (Its a performance boost to have deferred rendering at least on paper)

The trade off is that the render to texture technique kills MSAA. It also makes it hard to use alpha surfaces (what if you can see through the pixel, then the pixels that are behind the first pixel have no effects applied, unless the renderer goes through the first pixel, and then we are right back to where we were originally. )

Personally, I don't like deferred rendering. If the game runs slow. I'll upgrade my video card. I think at some point the developers will figure it out. But I'm guessing it became popular because of consoles (again like everything else in computer games) which had limited graphics power. Deferred rendering was probably necessary to get decent quality at a decent frame rate.

 

[VulgarDisplay]

Hopefully more developers get on board with Forward+ rendering which allows as many dynamic lights as deferred rendering, but also lets MSAA effect the whole scene.

http://www.youtube.com/watch?v=s2y7e3Zm1xc

 

[BrightCandle]

AA is mostly a glorified blur filter with FXAA and ilk. I don't use them be cause they always make things harder to see.

But if deferred rendering continues I can't imagine we will see much other than post processing blur filters for AA rather than something cleverer.