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floating point multiply == very very slow ?

PostPosted: Oct 19, 2004 @ 6:42pm
by jaguard

PostPosted: Oct 19, 2004 @ 6:48pm
by Kzinti

PostPosted: Oct 19, 2004 @ 7:32pm
by hm

PostPosted: Oct 19, 2004 @ 7:47pm
by refractor

PostPosted: Oct 19, 2004 @ 8:05pm
by Dan East

PostPosted: Oct 19, 2004 @ 9:56pm
by hm

PostPosted: Oct 20, 2004 @ 4:49pm
by jaguard
I was affraid of that :(.

Ok, I have to deal with FP math. So, did anyone actually checked how exactly slow floating operations are?

1. What about floating add and sub? How slow they are?

2. What is better - translate for example 4 floating variables to fixed, multiply them altogether, then translate them back or simply multiply them using floating multiplication?

PostPosted: Oct 20, 2004 @ 5:05pm
by xPeterx
Translation from floating point to fixed point usually involves a floating point
mul so you're better off using only fixed point whenever lots of data needs to be processed.

Converting back and forth between floating point and fixed point only makes
sense when you're doing it less frequently.

But there's no reason to be afraid of fixed point.
Just know your bits and what kind of precision you need. That's all :)

PostPosted: Oct 20, 2004 @ 5:17pm
by jaguard

PostPosted: Oct 20, 2004 @ 5:30pm
by xPeterx

PostPosted: Oct 20, 2004 @ 8:19pm
by refractor

PostPosted: Oct 21, 2004 @ 8:49am
by xPeterx

PostPosted: Oct 21, 2004 @ 9:01am
by Kzinti

PostPosted: Oct 21, 2004 @ 3:45pm
by abiemann

PostPosted: Oct 21, 2004 @ 3:56pm
by HTK