On Sun, 14 Jul 2002 22:13:32 +0200, "Rune" <run### [at] mobilixnetdk> wrote:
> Le Forgeron wrote:
> > Ellipsoid is only a linear transformation of a
> > sphere, so it won't help when the normals do not meet.
> 
> Does that logic apply?
> 
> Three normals of a sphere will always meet in the same point. But three
> normals of a ellipsoid will not always meet in the same point. I'm not
> saying that an ellipsoid is a solution, but just questioning this
> particular argument.
> 
> Rune

I believe he is refering to trangles that bend two directions. i.e. the triangle
itself looks
like:

____
        \
          \
            \______

According to the normals provided. And he is correct that under such circumstances
you can never find any primitive that has such a shape. It does occure to me that
in such instances one may be able to find two curves on an ellipsoid that may conform
to such a shape, but you end up tracing the interior of one and the exterior of
another,
not to mention it maybe not working at all, since all three corners could be distorted
in
ways that make it impossible to find any combination that would match. :p There has
got to be a better way of doing this, but... A method that used ellipsoid matching
could
probably 'fix' about 90% of the triangles in the average mesh, but that last 10% are a
problem. And in some objects the percentages could end up drastically shifting the
other way. Oh, well.. Hopefully someone will come up with a decent solution, probably
about the same time someone gets rid of coincident surfaces that are the true bane
of my existance. lol

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