[Radiance-general] organizing scenes with many light sources

[Gregory J. Ward]

Hi Lars,

If you lights are clustered together, you might be able to put them  
in an enclosing sphere and use mkillum to determine their collective  
output distribution, using only as many spherical illum's to light  
your space.  (Spheres are in general faster to use as lights because  
there is only one sphere per source.)

What is the exact configuration of your oil lamps?  Are they all the  
same?  Do you have any close-ups you can post somewhere?

-Greg

> From: "Lars O. Grobe" <grobe at gmx.net>
> Date: March 12, 2006 4:11:29 AM PST
>
> Hi!
>
> I am running in trouble (and into the limits of my cpu ressources)  
> with a scene that contains simply too many light sources. It is a  
> huge room lid by groups of small light (oil lights), all in all  
> there are thousands... Rendering is getting really slow now, and I  
> wonder how to get the most of the scene without loosing to much  
> visual accuracy.
>
> So far, I use a radiance sphere with a light modifier and xform  
> these spheres to all the positions in my room. I guess, as the  
> sphere is a basic and native radiance primitive, it should not make  
> a big difference if I use a sphere, a polygon or any other  
> primitive here? I remember that this question had been on this list  
> some years ago, but I was not able to find any post in my archives.  
> I also believe to remember that there has been someone doing  
> renderings of whole star fields with thousands or millions of  
> sources, am I dreaming or are there some projects out there like that?
>
> When I know how to load the light sources, the next is which  
> settings to use rendering them. They are all extremely small  
> compared to the room. I was also thinking if it might be worth to  
> wrap them into an illum "box", so that for at least the ambient  
> calculation, the groups of "point" (in fact sphere) sources would  
> appear as uniform area light sources.
>
> Thank you for sharing ideas and experiences, at the moment I am not  
> able to get any result in a reasonable time.
>
> CU Lars.