"Meow Cat" <wyr### [at] hotmailcom> wrote in message
news:3e4fb0bd@news.povray.org...
>
> The easy demonstration about how the 'misfeature' occurs is to render the
> 'slope bug' scene with quality setting lower than 6, say, +Q3. This way
both
> sides look equal. With +Q6 or higher, the backfacing intersection kicks
in,
> and this time the intersection normal points inwards! Therefore, near the
> top of the sphere, we first get totally transmitting blue on the incoming
> ray, which is basically invisible. With the outgoing ray, however, the
> normal points inwards, which in this case is almost entirely downwards,
thus
> giving the opaque yellow at the other end of the color map.

I for one am glad you figured this out, I suspected it could be the inside
of the sphere but I was thinking it would have had to be using a matching
interior_texture (opposite of possible fix?). Which goes to show how little
I understand still about these kinds of things. I see you talked a little
more about it with Christopher Huff in the original thread.

Bob

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