> What did I happen to not understand?



You seem to be on the right track. But... well, let me see.

It seems like you forgot to set the material finishes to 0 on your white walls?
Right?
This is the most important step because without it you will never get realistic
bouncing of light off the surfaces.

In that old tutorial I used
finish {
        ambient 0
        diffuse 1

for all materials except the sky sphere.

Sometimes I use diffuse 0.9 or even 0.8 in outdoors situations only, depends on
the situation, but ambient finish should always be 0 when using radiosity.

Another thing, you can never use the same radiosity setting for bot indoors and
outdoors situation. Unless you cheat with fill lights perhaps. But if you want
to mimic real daylight it is not possible. The light on the outside will always
be brighter than the light bouncing inside the room. The outside light is more
direct, while the inside light is mostly indirect. Our eyes will automatically
adjust to this in reality. No camera can take pictures both inside and outside

do it.


inside you have to use two different radiosity settings for each situation.

One tip: try to avoid using colors for surfaces that are 100% white (or 100%
black for that matter) they can never be realistic.

One more thing. The recursion limit of 5 is probably a bit too high for your
scene as you are getting more light in through the windows than in the tutorial.
"recursion limit" controls how many times indirect light bounces off the
surfaces. Where there is little light coming in you typically use higher values
to get more light in you room. Every situation is unique so you may have to try
out a few variations. Too much recursion washes away the contrast, too little
and your scene is too dark. Only do this AFTER you set the material finishes to


Try playing with the balance between "recursion limit" and "brightness".

I usually use recursion limit of 3-5 indoors and 1-3 outdoors.

If you start getting "dirt" or dark smudges on your surfaces, that means you are
on the right track. Those you should be able to get rid of in the final
rendering by raising "count" to 400-600. It takes longer to render but that is
the necessary evil of radiosity.

Hope this helps and happy raytracing.

Hildur K.

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