In article <3d0afa81@news.povray.org> , "Karl J. Anders" 
<kar### [at] webde> wrote:

>> There was no old behavior.
>
> Sorry, but that's wrong! 3.1g (mac) at least did return <0,0,0> and no error
> message - and this is, though mathematically definitely incorrect, quite
> useful in many cases. And some include files from other people, like
> TORSPLINE or CHEAP_SWEEP suddenly don't work as before :(
>
>> There never was a legal result being returned for a zero length vector and
>> the documentation clearly stated it.
>
> Sorry, but no, it didn't ! It does so with all 3.5 betas, but not with 3.1g.

It was pure luck that some versions of POV-Ray would return a valid result
in some cases.  In order to normalize the length one has to divide by the
length.  Consequently on systems were divisions by zero do not cause a fatal
exception some undefined garbage would have been returned.  That this
garbage would most of the time be zero on those platforms doesn't make it
the correct result...

Anyway, I am going to ignore any further messages posted to this thread in
order to end this discussion.

    Thorsten

____________________________________________________
Thorsten Froehlich
e-mail: mac### [at] povrayorg

I am a member of the POV-Ray Team.
Visit POV-Ray on the web: http://mac.povray.org

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