scott <sco### [at] laptopcom> wrote:
> It does simply return the reflected colour, because the engine doesn't 
> actually display the reflected ray colour, does it?  It averages all the 
> rays together, including the refracted ones.

  A reflection *adds* to the color of a surface, it's not averaged with it.
If a surface reflects a black surrounding, it doesn't become darker. It
can only become lighter if it's reflecting a light surrounding.
  Basically if you have a reflecting surface with nothing to reflect
(everything around it is completely black), that's more or less equivalent
to not having reflection at all. (Ok, this is the most basic reflectivity
model, and real-life surfaces might behave slightly differently, but not
too much. The basic reflectivity model is often good-enough for simple
images.)

  Now, if you simply averaged the black reflected rays with the refracted
rays the end result would be darker and more opaque. In regular raytracing
the reflecting rays wouldn't have any effect on the coloring.

  Additionally, at which step is the surface's own color taken into account?
It cannot simply be dropped. It has to be added to the mix somewhere.
(The surface's own color is not only affected by its pigment, but also
by lighting.)

-- 
                                                          - Warp

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