altivec and linux

Samsara · 08-08-2005, 07:05 PM

I've learnt that the floating point extension of the PowerPC chip, AltiVec, is specifically good at graphics and video manipulation, including H.264 compression. Is this advantage also fully realised under Linux? Meaning, do Gimp, Cinepaint, Blender, Yafray etc., compiled with gcc, take full advantage of AltiVec? Or do programs have to be written specifically in a way that allows them to benefit, e.g. particular algorithms benefitting more than others?

Thanks,

Samsara
.

jtshaw · 08-10-2005, 06:12 AM

I can't comment on all those programs, but I can tell you that gimp does utilize altvec in some way if you build it with the correct flags. How well it uses it is anyone's guess.

In general, it helps for programs to be specifically designed for a feature like altvec because it is very hard for a compiler to turn "normal" code into code that would have a benefit from vector processing.

GCC (which is Apple's compiler of choice as well..) does fully support the altvec extensions.