"clipka" <nomail@nomail> wrote:
> So it was never actually intended to be true radiosity, but just a thing that
> did something similar. Therefore when refering to "the original paper" we
> shouldn't be talking about a *re-write* but a completely new feature...

Having just taken the time to read the original paper by Greg Ward et al., I'll
have to correct myself:

- The algorithm described by Ward et al. is NOT radiosity either.

- The algorithm used by POV-Ray DOES come very close to that described by Ward
et al.; there are a few differences, but none that would justify a complete
rewrite. The core of the implementation is plain Ward et al.


So I guess most people complaining that Radiosity works much better in other
programs than in POV, and then maintain that it should be re-implemented
according to Ward et al.'s paper, haven't read the paper themselves (or have no
idea whatsoever about the internal workings of POV's implementation).

This misconception may have arisen due to some people rightly claiming that
"what POV-ray does is NOT radiosity", referring to Ward's paper as a witness to
their claim - which other people understood as that Ward's paper would describe
true radiosity. Well, it doesn't.


For all those who still ask for TRUE Radiosity to be implemented in POV, I can
give you one clear statement:

    This will never happen.

From what I gather from Ward's paper, true radiosity requires the geometry to be
subdivided in - roughly - equally sized patches. This is easy to do with mesh
based geometry, but infeasible with the mathematical representation POV-ray
uses for objects.

That's the bottom line of it.

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