This is a port of NVIDIA's original FXAA v2 shader (the console version), with further pre-compute optimizations added by Matt DesLauriers. In short, FXAA is a single-pass, 1:1 anti-aliasing post-processing effect. Compared to straight super-sampling or MSAA, it has a lower quality, but is much faster. Love2D's MSAA was too slow for a project I'm working on, so I quickly hacked this together based on Matt's glslify shader. I've added an optional sharpening stage, which uses a very simple algorithm.
main.moon contains an example class FXAACanvas, which wraps canvas draw calls and applies FXAA and sharpening on render. You can fine tune all FXAA params and the sharpening strength, as well as the number of FXAA passes (uses nested canvas render targets).
Here's a screenshot of the demo file (click to view full size):
