Mick West | Refraction Simulator - TECHNICAL explanation @MickWest | Uploaded February 2019 | Updated October 2024, 3 hours ago.
This is a highly technical explanation of how the Metabunk refraction simulator works. You will need a basic understanding of 2D vector math and code in order to follow it. It is intended for a technical audience.

I'm posting it partly so people, if they wish, can verify the correctness of the simulator, and maybe suggest/implement some improvements.

Link to Metabunk Refraction Simulator:
metabunk.org/refraction

Discussion thread:
metabunk.org/simulating-atmospheric-refraction.t7881

The simple explanation of how to use it
youtube.com/watch?v=8zzEWy5SGKg