Alain <ele### [at] netscapenet> wrote:
> JLH nous apporta ses lumieres en ce 2007/06/18 09:08:
>   Thorsten
> >
> > "sunpos" requires an input of h:m:s, lat long, to provide the correct
> > direction of the sun's light. This requires an implicit assumption of the
> > direction of the N-S meridian. I was wanting to find out if this was the
> > z-axis. Since then I have found in the help files that the N-S line is
> > indeed the z axis. Now I just wonder at the answer to the second
> > question-can one do global rotations of whole scenes? I suspect the answer
> > is no. JLH
> >
> >
> You can do a global rotation of a whole scene. Here is how you do it:
> Option 1: Wrap your whole scene, optionaly exepting the camera, in a global
> union. Rotate that union. If you want, you can leave out some or all of your
> light(s).
> Option 2: Rotate the camera
>
> --
> Alain
> -------------------------------------------------
>    My wife is such a bad cook, in my house we pray after the meal.
>     Rodney Dangerfield

Alain: Thank you for your reply. That is what I wanted. The reason for the
request is that architects and planners often use a "conventional" north in
their drawings so that the coordinates are simplest (i.e. North is taken
parallel to some street when in reality it is some angle away from north).
All is irrelevant until you are interested in the actual time resolution of
sun shadows, in which case the whole scene must be rotated wrt the sun to be
geographically correct. This is the situation I have at the moment. So there
is at least one operation in POVRAY that is
North dependent. JLH

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