Ron Parker <ron### [at] povrayorg> wrote:

> On 4 Jan 2001 08:06:39 -0500, Geoff Wedig wrote:
>>Is this correct?  For some reason, I don't think it is, or at least it's
>>over-simplified.  I've had two media objects, one within the other, and
>>gotten the media of both in the shared region.  It seems that media is only
>>calcuated at the bounds of the actual object.  Another object inside the
>>media object doesn't affect this, quite.  But if the object inside is solid,
>>then the media should stop there, of course.  If it's totally transparent,
>>we see the media of the surrounding object.  If it's partially transparent,
>>the media is affected by that surface, but continues the computation for the
>>interior of the inside object.  Have I got that right?  If so, then I don't
>>see the problem with intersecting objects.

> You're right, my explanation was oversimplified, to the extent that media 
> for both objects is calculated inside the inside object.  But the media 
> in the larger enclosing object is actually calculated on three paths: First,
> on the path from the outer object to the inner object.  Then, on the path
> inside the inner object.  Finally, on the path from the inner object back to
> the face of the outer object.  

> However, this doesn't change the fact that changing the way media is 
> calculated for triangles with different interiors would break existing 
> functionality.

I don't see that it'd *break* functionality.  If there's a constant ior,
then everything should be as before.  I do see a number of big problems for
it, though (which I've posted elsewhere)

Geoff

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