/*
BEWARE: big, ugly, nasty function! NOT efficient code!
I really suck for writing something that looks like this!
This is what happens when you keep adding to code for a
period of years with no real foresight. Mea culpa!!!
Please excuse the ugliness of this function. I will
rewrite it eventually, but it seems to work for now…
*/

Source: Direct link to the source code
Software: Fast Light Toolkit
Programming language: C