Anti-Aliasing: A VGC Thread

[caffeinade]

So I decided to make a thread about Anti-aliasing, hopefully people can learn something from it.

MSAA (Multi Sample Anti Aliasing) basically just renders geometry at a higher resolution.
SSAA (Super Sampling Aniti Aliasing) Just renders everything at a higher resolution.
FXAA (Fast Approximate Anti Aliasing) Pretty much just blurs the whole screen.
SMAA (Subpixel Morphological Anti Aliasing) Detects edges and blurs them.
TAA (Temporal Anti Aliasing) Takes information from previous frames

MSAA and SSAA:
If you are using MSAA or SSAA (or something that behaves in a similar manner) it is fantastic.
With MSAA and SSAA you are just rendering at a higher resolution and using the information to output a more accurate image.
This is kinda the one way to do it, if you want the best results.
Depending on the resolution used and how much AA you apply (4xMSAA, 16xMSAA, ect) you may or may not remove all the aliasing, but you will not harm image quality.
The image will not be blurry.
Both methods are super expensive, especially for a tablet.

FXAA:
It sucks.
It blurs everything, even the textures.
It is a post process effect that is pretty much just a blur filter.
It has next to no performance penalty.

SMAA:
It is similar to FXAA but it detects edges in the final render and blurs them.
It is a post process effect that sometimes harms textures, but is otherwise decent.
It has a limited performance penalty.

Temporal Anti-aliasing:
Essentially takes previous frames and the new frame and averages the results.
It is, perhaps, the most complex mainstream AA method.
Downsides include Blur and Ugly artifacting.
Artifacting is most prominent when the camera moves or there are fast moving objects in a scene.
Textures are harmed by this method.
It can look really good in stationary scenes, it does a really good job at removing jagged edges.


So to put the major AA methods in order of what I personally would use:
SSAA, it really is the best
MSAA, it is a good compromise if you cannot afford SSAA
SMAA, it works and does not harm the image quality too much
FXAA, it is better than having temporal artifacts
Temporal anti-aliasing, destroys the image in motion but can be really good if nothing is moving

When people say: "why doesn't Nintendo use AA".
Well this is why.
AA is complicated, if you don't have the power to do it properly, you risk image quality.
That being said, they should give people the option to enable SMAA.