Thorsten Froehlich wrote:
> 
> In article <3820f651@news.povray.org> , "Chris Jeppesen"
> <chr### [at] digiquillcom> wrote:
> 
> > And I got rid of 607 warnings with a simple #define float double
> 
> and by forcing float to be double you just make rendering slower.  

That's not true.  By amazing coincidence, the FPU (at least for intel arch)
is the same size as a Visual C++ double.  So if your code is using floats, 
they have to be converted to doubles before stuffing in the FPU (and 
converted back to float on the way out of the FPU).  So you lose precision 
and take a performance hit by using floats.

No comment on the #define float double solution though. ;)

It's also interesting that since the '486, FPU mul/div is faster than
integer mul/div.

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