---
On 29-Sep-07, at 1:02 PM, Charles Yeomans wrote:
> On Sep 29, 2007, at 12:26 PM, Norman Palardy wrote:
>>
>> What about getting rid of the bitshift ?
>>
>> i = &h5f375a86 - (i/2)
>
> I tried this (actually i\2). It saved a few ms, but that's it.
Similar results here - it's definitely faster but still slower than
the built-in sqrt wrapper.
---
On 29-Sep-07, at 1:46 PM, Marco Bambini wrote:
> What is fast for you?
> I mean, how many Microseconds it should take the FastSqrt function in
> order to be "fast enough"?
I'm not measuring a single call. In a real-world 3D app I have to
normalize several thousand 3D vectors (among many other things) plus
draw everything at (ideally) 60Hz. Normalizing the vectors in C code
(loop and all) using an inlined sqrt approximation is far and beyond
faster than anything I can muster in RB code - something in the range
of 20-30 times faster - no exaggeration. In this case "fast enough"
is literally the difference between getting interactive framerates
and watching a slideshow.
Frank.
<http://developer.chaoticbox.com/>
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