Orchid XP v7 <voi### [at] devnull> wrote:
> As best I can tell, the algorithm described just sounds like POV-Ray's 
> radiosity with an infinitely low error_bound. (I.e., always resample.) 
> But applied to *all* terms, not just diffuse illumination...

  Except that POV-Ray doesn't have the concept of BRDFs.

  Also, brute-force renderers take a slightly different approach at
rendering than POV-Ray's radiosity. What the latter does is that when
a ray intersects a surface, it sends tons of rays to all directions
(unless it can interpolate from nearby values calculated earlier).
AFAIK brute-force renderers only send one ray to a random direction.
This means that a ray hitting a surface doesn't spawn a thousand new
rays, but only one.

  There are advantages and disadvantages with this. The advantage is that
the renderer never gets stuck on things like highly reflective/refractive
objects because it's only following one path, not thousands (each one of
which in turn would spawn thousands of new paths, etc). Another advantage
is that you don't have to fix a number of rays to send per intersection
point, but you can simply let it run for as long as you want.

  The disadvantage is the graininess, of course. Overall, however, the
correct result is approached faster in this way than with the method
POV-Ray uses. (This is assuming we are looking for the perfect solution.)

-- 
                                                          - Warp

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