[Radiance-general] Getting numerical errors while using secondary light sources...

[Gregory J. Ward]

Hi Ilya,

My guess is that you are seeing sampling areas associated with your  
exterior obstruction, which will be translated into the window's  
output distribution by mkillum as a fairly sharp cut-off since it is  
on the other side of the street.  Basically, I recommend reducing  
your -ds setting even further (to 0.1 or 0.08) in your final rtrace,  
in hopes of reducing the parallax error of the window sampling.  Even  
better would be to set -dj 0.9 and give the same point to rtrace many  
times, then average the result in a post-process.  This will  
eliminate any direct sampling errors, which I suspect are the problem  
in your particular case.

-Greg

P.S.  Very nice analysis and presentation of your results, by the way.

> From: webmaster at audice.com
> Date: December 16, 2005 11:18:10 AM PST
>
> Dear friends,
>
> I'm trying to make use of advantages of the "secondary" light sources
> to speed up the indoor irradiance calculations.
>
> In the test below we have compared a daylight factors in a room,
> calculated along the central depth axis of the floor.
>
> The room parameters are:
> 3.2 meters - width,
> 5.6 meters - depth,
> 2.5 meters - height.
>
> ...