Tim Nikias v2.0 wrote:
> Hi all! I've been using Radiosity every now and then, but am not quiet
> up-to-date with that clipping-thingy which was removed now in the latest
> version. Anyone care to elaborate and perhaps post an example pic of
> radiosity in 3.5 and 3.6? I'd like to know if I have to to some new
> radiosity-tests to update a page on my website, but for that, I'd need to
> know what exactly this clipping did...

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).

Kari Kivisalo posted a really quite minimal example some time ago:

Subject: Clipped radiosity samples
Date: Tue, 04 Mar 2003 16:37:49 +0200
Newsgroups: povray.advanced-users
From: Kari Kivisalo
news://news.povray.org/3E64BA3D.883AE539@luxlab.com
http://news.povray.org/3E64BA3D.883AE539@luxlab.com

Subject: Clipped radiosity samples
Date: Wed, 05 Mar 2003 17:20:39 +0200
Newsgroups: povray.binaries.images
From: Kari Kivisalo
news://news.povray.org/3E6615C7.EE9E97E9@luxlab.com
http://news.povray.org/3E6615C7.EE9E97E9@luxlab.com

Christoph

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