> The clipping in 3.5 reduced the color of radiosity prediction values
> calculated by ra_average_near() to [0..1].  This means that in scenes
> which contain very bright areas results may differ - of course not in
> direct appearance, there it will always be color rgb <1,1,1>.  Note this
> is different from what you can do with max_sample - this limits the
> brightness of samples when taking them in ra_gather().
>
> In practical use you will mostly observe differences with scenes using
> higher recursion limits combined with strong light, for example a room
> illuminated by sunlight coming through a small window.  And of course
> this is also important when dealing with high dynamic range image output
> (although this is not yet possible in official POV or unofficial
> versions currently available).

Ah, thanks. That technical part at the beginning was a little over my head,
as I am not firm in the source of POV-Ray. Still, with spending some thought
and common sense I could make sense of it. A description well done, I must
say! :-)

I'll have to do some quick tests to figure if I've thought correctly, but
what you're implying is that in 3.5, Radiosity was clipped and thus, a
bright spot coming through a window wouldn't illuminate the room (via pure
radiosity, that is) to an extent which would have been more real, right? I'm
quiet fuzzy about where, what and when it gets clipped, but I think I have a
clue where to start experimenting now. And its always fun to experiment with
POV. :-)

Thanks again,
Tim

-- 
"Tim Nikias v2.0"
Homepage: <http://www.nolights.de>

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