Hm interesting, I knew it from Quake and implicitly assumed that it was Carmack's trick. But Wikipedia has some more history: https://en.wikipedia.org/wiki/Fa

Hm interesting, I knew it from Quake and implicitly assumed that it was Carmack's trick. But Wikipedia has some more history: https://en.wikipedia.org/wiki/Fast_inverse_square_root#History_and_investigation https://en.wikipedia.org/wiki/Fast_inverse_square_root#Histo...