Thorsten Froehlich wrote:
> 
> [...]
> Well, if it is with both versions it then suggests it is some math library
> difference (in the pow C library function).  Given that gcc on Linux and
> CodeWarrior on Mac OS use two completely different math libraries but the one
> used by for the Windows compiles is probably the same it may well be a bug or
> non-standard implementation.  Probably some testing on other platforms is
> necessary to verify this...
> 

The pow() function indeed seem to be the reason, replacing

z^1.48893

with

abs(z)^1.48893

leads to identical results in both Windows and Linux version.  Results
with negative base and non integer exponent are not defined, i suppose you
would have to catch this case inside Povray to make sure to get identical
results in all versions.

If this is not handled inside Povray i think it should be mentioned in the
docs (for example at the pow() function description), especially in
isosurface you do not necessarily recognize this at the first glance.

Christoph

-- 
POV-Ray tutorials, IsoWood include,                 
TransSkin and more: http://www.tu-bs.de/~y0013390/  
Last updated 11 Apr. 2002 _____./\/^>_*_<^\/\.______

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