[Radiance-general] Re: physically-based landscapes

[Santiago Torres]

Hello. Thank you very much for your reply.

> From: Greg Ward <gward@lmi.net>
>
> >
> > void colorpict skyfunc
> > 7 noop noop noop sky_orig.pic fisheye.cal fish_u fish_v -rx 90 -rz 180
> > 0
> > 1 1
>
> What is the last real argument (A1=1) for?  I think fisheye.cal just
> ignores it.

Yes, that`s right. It`s my mistake, I was trying something different first
and it just stayed there, I didn`t realize.

> What is in sky_orig.pic?  Is it possible that you exposed it with pfilt
> or something -- you need to have the original values in there.  The
> direct output of rpict should work, but passing it through pfilt would
> not.

I made it like this:

rpict -vta -vd 0 0 1 -vu 0 1 0 -vv 180 -vh 180 -ab 1 -x 2048 -y 2048
sky_orig.oct > sky_orig.pic

And used that file. sky_orig.rad is a copy of the sky deffinition in the
Radiance tutorial. Then tested illuminances with:

echo "0 0 0 0 0 1" | rtrace -h -I+ -w -ab 1 sky_alter.oct

> Gensky creates a separate source for the sun, whereas it gets included
> as a small spot in sky_orig.pic, which the indirect calculation is
> hard-pressed to find.  To get it to work as gensky, you would have to
> take the solar source from gensky and reapply it in your model.

Thank you, I will try it. But I still don`t understand why the mapping to
the window works fine, if it is also coming from a pic file. Isn`t it the
same if it is comming from the window or from the sky source?

Thanks again for your help and best regards,

Santiago.