"Chris Huff" wrote:
> The flexibility argument is *why* I think a new object
> type would be useful...

> However, that data is really only used in the parsing
> stage...maybe something that will generate a mesh:
> mesh {
>     // usual mesh stuff...triangles, etc
>     boned_mesh {vertex and bone data}
> }
> The best of both worlds...it could let you define
> "ownership" of each individual vertex, or use
> "deformation fields" to do the job, and would result
> in a mesh, and not save irrelevant data or interfere
> with the existing mesh syntax.

Sounds better.

> The syntax would probably not be very useable anyway...
> better to add a general "bones" feature and let
> macros/includes do the IK.

I agree.

To define "ownership" of each individual vertex is exactly what I had been
thinking about. However, several bones should be able to own the same
vertex, controlled by weights. That would be a huge amount of data to
generate and to store. That's why I talked about letting strengths control
the weights, so calculations can be done on the fly and don't have to be
stored. This will probably be slower though than just reading stored data,
and identical calculations would have to be done for every frame, which is
kind of a waste. Experiments should be done to find the most advantageous
method.

Anyway, how would you define a bone? I've thought of it as a line between
two points. A field with a user-defined strength and radius would surround
this line segment and affect vertex points and normals near it. They would
be transformed by a transformation assigned to that bone. But actually it
would be better to have *two* transformations assigned to each bone. One for
each end. That's because in reality when we twist our limbs (for example our
wrist), the twisting actually occurs along the whole limb and not just at
the joints. So there should be two transformations assigned to each bone, or
maybe one transformation and one twist amount.

Have you had any thoughts on how a bone would work? I'd be very interested
in this.

> > You're a bit late. I already mentioned that in my
> > first message. Did you bother to read that message?
>
> Ouch... :-)
> I did, but I must have misinterpreted what you were
> saying...

Never mind! It was a joke kind-of... :)

Rune
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