Fast inverse square root as seen in Quake (as mentioned in other comments) https://en.wikipedia.org/wiki/Fast_inverse_square_root#Overview_of_the_code https://

Fast inverse square root as seen in Quake (as mentioned in other comments) https://en.wikipedia.org/wiki/Fast_inverse_square_root#Overview_of_the_code https://en.wikipedia.org/wiki/Fast_inverse_square_root#Overv...