andrel wrote:
> Have you thought about more complicated things, like
> some flesh bulging out when a join moves? Simply because
> of conservation of volume.

I'm just getting started here.

> Are there restrictions on the angle of the joints?

When I first developed the modeler, I had upper and lower
limits for everything.  Then I decided to simply lock the
angles (if the user wanted them locked).

> Both things are not so well done
> in Poser IMHO, there it is too easy to overstrecht and
> even do 360 turns on any joint, which horribly deforms
> the mesh.

Then don't bend them that far.  I put locking in the modeler mainly
because dragging a 3d end point on a 2d screen is very prone to error if
some form of locking is not in play.  Locking is no longer enforced in
the .INC files, because the animator should know what he/she is doing.

> There is also the issue of the muscle contracting
> giving mesh deformations at the position of the muscle
> and not close to the joint.

The math for soft tissue modeling is not fun, which is why I've not
gotten to developing it yet.

> I think that the one vertex one bone and even the Unreal model are set up
> to fascilitate fast computation.

And a smaller set of data to manipulate.  Right now the modeler only
needs to know the bone to which the vertex is attached, and the
coordinates of the vertex, local to the bone; this allows for a static
data object size.  Allowing for multiple bones greatly complicates
things.

> In the context of ray tracing this is
> not so much an issue (unless we do real time ray tracing). If I had
> to do it I probably start with something of the Unreal model as a first
> approximation and then for a number of angles of the joint compute
> the position of the vertices. Then do a sort of relaxation step to get
> the mesh a bit nicer, and perhaps account for compression effects.
> Finally fit a curve through the positions as a function of the joint
> angle. That is a lot of computation, but it has to be performed
> only once for the model.

My modeler is designed for exporting the coarse meshes for subdivision
surfaces, so mine aren't getting done in real time anyway.

Regards,
John

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