Does anyone know about the importance of the SIGMOID_METHOD/SAW_METHOD
switch in 'radiosit.cpp', line 432:

#ifdef SIGMOID_METHOD
          weight = error_reuse / info->Current_Error_Bound;  /* 0 < t < 1
*/
          weight = (cos(weight * M_PI) + 1.0) * 0.5;         /* 0 < w < 1
*/
#endif
#ifdef SAW_METHOD
          weight = 1.0 - (error_reuse / info->Current_Error_Bound); /* 0 <
t < 1 */
          weight = sqrt(sqrt(weight));  /* less splotchy */
          /*weight = sqrt(sqrt(sqrt(weight)));   maybe even less splotchy
*/
          /*weight = weight*weight*weight*weight*weight;  more splotchy */
#endif

By default 'SAW_METHOD' is used, but i have no idea why and what the
difference between the methods is.  Also note the commented additional
lines.

A search in the newsgroups archive revealed Margus Ramst had already asked
this quite some time ago, but with no reply:

Subject: radiosity sigmoid_method?
Date: Thu, 03 Dec 1998 00:11:07 +0200
Newsgroups: povray.programming
From: Margus Ramst <mar### [at] peakeduee>
news://news.povray.org/3665BAFB.D420BD6E@peak.edu.ee
http://news.povray.org/3665BAFB.D420BD6E@peak.edu.ee

Christoph

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