I can shed some more light on the 1/sqrt(x) topic. I coded
a vectorized version of this function for the Ardent Titan
"graphics supercomputer" in 1987. I did not originate
the idea but got it from Cleve Moler, original founder
of MathWorks and author of MatLab.
I did some work with Gary Tarolli when he was at Stellar,
a competitor of Ardent which eventually merged with
it to form Stardent computer. He may have picked it up there.
The function was widely used in the Ardent 3D code base.
I also had a 1/cuberoot(x) version which worked in a similar
but slightly more complex manner. It was not used in 3D
graphics but did find application in some
mechanical engineering analysis programs.
- Greg Walsh
Slashdot Mirror
I can shed some more light on the 1/sqrt(x) topic. I coded a vectorized version of this function for the Ardent Titan "graphics supercomputer" in 1987. I did not originate the idea but got it from Cleve Moler, original founder of MathWorks and author of MatLab. I did some work with Gary Tarolli when he was at Stellar, a competitor of Ardent which eventually merged with it to form Stardent computer. He may have picked it up there. The function was widely used in the Ardent 3D code base. I also had a 1/cuberoot(x) version which worked in a similar but slightly more complex manner. It was not used in 3D graphics but did find application in some mechanical engineering analysis programs. - Greg Walsh