Shader post-processing in a hurry

from blog Computer Graphics & Programming with Pekka Väänänen - 30fps.net, | ↗ original
So you have written a cool raymarcher but for some reason it looks cheap. There are a few basic things you can always do to improve the perceived image quality: tone mapping, avoiding clipping color channels, color grading, adding glow, anti-aliasing and dithering.