bseeg@spectra.COM (Bob Seegmiller) (02/08/90)
At the '86 SIGGRAPH Conference, in the Image Rendering class or at one of the Forums, Rob Cook of Pixar gave passing mention of a method for computing the inverse square root (n^-(.5)) of a number that was faster(!?) or comparable in speed to taking just the square root itself. I've lost the note, and my own hack at it via Newton's method has proved to be highly unstable. Does anyone out there know of or remember the reference? Thanks in advance.
bseeg@spectra.COM (Bob Seegmiller) (02/08/90)
SORRY to repost: inews mangled the .sig file inclusion which had my return address At the '86 SIGGRAPH Conference, in the Image Rendering class or at one of the Forums, Rob Cook of Pixar gave passing mention of a method for computing the inverse square root (n^-(.5)) of a number that was faster(?!) or comparable to the square-root method itself. I've lost the note, and my own hack at it via Newton's method has proved to be highly unstable. Does anyone out there know of or remember the reference? Thanks in advance. Bob Seegmiller UUCP: ...!nosc!spectra!bseeg