AA and AF Demystified

We have all seen these video options in our favorite games. We have found that when we activate these options, our game suddenly looks prettier. But what is anti-aliasing and anisotropic filtering, and how do they work?

In a nutshell, AA smoothes out jagged lines:

“Let's start with AA (antialiasing). The name is sort of self-explanatory, as long as you know what aliasing is. Dictionary.com defines aliasing as a ‘jagged, stairstep effect on curved or diagonal lines that are reproduced in low resolution, as on a computer printout or display.’

“Anisotropic filtering is a method of improving the way the insides of objects look—all the parts between the edges.”

So what?

With AA and AF one can improve the visuals of a game, but often at the cost of performance. Also, AF tends to depend on the type of game that one is playing:

“AF makes the most difference on long surfaces that are turned at a very steep angle from the camera. Therefore it makes a really big difference in some games, and not in others. In a real-time strategy game, for example, where you spend all your time looking at the ground at a very shallow angle (if not straight down), AF isn't going to do a lot. In racing games, online RPGs, and flight simulators where the ground stretches way out in front of you, applying AF is perhaps the best visual quality improvement you can make. 3D shooters are a mixed breed. They tend to have plenty of corridors and ground at sharp angles to the camera, but some games have a lot more of this than others.”