Fast InvSqrt() (52192154611).jpg

Fast Inverse Square Root is an algorithm(based on "magic number" 0x5f3759df) that quickly(3–4 times faster, but loss of accuracy <~1%) estimates the inverse of the square root of a float variable. Method was developed by Cleve Moler and Gregory Walsh in 1986. This optimization was used in Interstate '76 and Quake 3 Arena video games in late 90s

Artist: Exey Panteleev. License: CC BY 2.0. Source

#project-geekography-by-exey-panteleev-nude-portrayals-of-computer-technology #1980s