Inspired by N. Conway's post, I got to thinking about how radiosity interacts
(or IMHO should interact) with the surface diffuse.

Basically, if anyone can spot any misconceptions, or fill in the gaps, in what
follows, please do so. Please.

A white rough surface will have a diffuse of 1, since all light is diffusely
reflected.
A black rough surface will also have a diffuse of 1, since all light is
absorbed, rather than reflected.
A reflective surface should have its diffuse + reflection component adding to 1.

The amount of light diffusely reflected by an object (and therefore used in
radiosity calculations) is: (1-reflection) * rgb - i.e. if a surface is 0.5
reflective, you should set the diffuse to 0.5

Now, the only other thing I can't quite work out is that, if specular highlights
are just another form of reflection, how do you adjust diffuse to take account
of a particular specular setting?

(btw my brain is small - I'm not really considering any colours except black,
white and gray here)


--
#macro A(V,B,C,R)#while(B-256)#if(V-128/B>=0)sphere{0,.5translate<C-4R-1,9>
pigment{rgb<1-C/8R/2C/8>}}#local V=V-128/B;#end#local B=B*2;#local C=C+1;#
end#end A(234,1,0,2)A(85,1,0,1)A(81,1,0,0)light_source{-5 1}//Tom Melly

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