Pizer’s Weblog

programming, DSP, math

Posts Tagged ‘approximation

Fast Inverse Square Root

with 3 comments

The article “fast inverse sqrt” came to my attention. It shows a small function written in C which is amazingly fast and approximates sqrt(1/x) pretty well. Appearently it was used in the Quake source code to speed up vector normalizations. But how does it work? Also, can it be improved?

Read the rest of this entry »

Written by pizer

October 12, 2008 at 1:17 am

Posted in Math

Tagged with , ,