"Christoph Hormann" <chr### [at] gmxde> wrote in message
news:c7v675$29l$1@chho.imagico.de...
>
> - you seem to discard any normal vectors specified for the mesh - this
> might often not be what the user wants and more important using the
> normal vectors could save you quite some computations (i.e. determining
> the neighbouring triangles).

I was pondering about the usual scenarios that users specify the normals
and apply the subdivision. Do they want part smooth/part flat shading,
or normal effect (bump mapping, etc) or maybe even crease controls?

Before I can get a sense of practical demand, I decided not to use the
supplied normal for anything. But this is really open for options. After
I see more examples that requires normal control, I would love to implement
that in.

About the computations, determining the neighboring triangles is needed
for subdivision. So it is a must anyways.

> - i can't find a reason why it should only work for mesh2 and not mesh.
>

There is really no reason that it would not work with mesh. But often
enough, mesh objects are built without precisely matching vertices. The
subdivision will result in surfaces with gaps (remember shrinking
boundaries).
take a look at the examples chesmsh.pov (knight object is subdivided)
http://www.cise.ufl.edu/~xwu/Pov-Sub/pics/chesmsh.jpg
With that said, I might still add the support for mesh in in the next
update.

Best wishes to all,
Xiaobin

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