Game Development Reference
Figure 14.7. Driven deformation of a simple mesh geometry (see Color Plate XIV).
Figure 14.8. Under the influence of gravity, the geometry stays in shape just by means of
shape matching of the local neighborhoods (see Color Plate XV).
14.4 Volumetric Effects
While the shape matching of the surface vertices has a huge impact on realism,
it still is not a complete solution for our problem, since what we are missing
completely is the influence of the interior of the body on the surface of it.
A more practical problem with this is that if only shape matching is used, the
surface mesh will not follow the bone motion very well, and too much contribu-
tion of f rest is needed, which renders the simulation unrealistic. The model we are
dealing with is a surface mesh. In a realistic material simulation, the surface ver-
tices should not only experience forces from its neighbors but also forces acting
on the surface from the inside. Here we run into a problem. We do not have any
information about the inside of the mesh.