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Working with Deformable Envelopes
Once you've got the deformable envelopes working the way you want to
control overall skin deformation, you may want to adjust the finer aspects of
skin control:
■ Skin bending, twisting, sliding, and scaling about single links are controlled
at the Link sub-object level. See
Adjusting Link Parameters on page 4644.
■ Link sub-object primarily controls the deformation spline on page 7949. You
use Link sub-object options to affect the shape of the spline and the
smoothness of the skin. See Adjusting Link Parameters on page 4644.
■ Crease behavior where links meet and bend is controlled at the Link
sub-object level with
Joint Intersection on page 4734 parameters.
■ Muscle bulges as your character's limbs move through a range of motion
are controlled at the Bulge sub-object level. See
Creating Bulges on page
4649.
■ Skin stretching, generally between non-contiguous links, is controlled at
the Tendon sub-object level. Tendons provide a secondary movement (a
pulling or stretching) based on links farther up or down the skeleton. See
Creating Tendons on page 4653.
See also:
■
Link Sub-Object on page 4725
■ Bulge Sub-Object on page 4737
■ Tendons Sub-Object on page 4747
Working with Rigid Envelopes
Vertices influenced by a rigid envelope follow the link itself rather than the
deformation spline, like deformable vertices do. Low vertex-count models
used for games are typically connected to the skeletons with rigid envelopes
to simplify export to game engines. In such a case, each vertex can be simply
described as assigned to a specific link. It can be located by giving a length
along the link, a distance from the center of the link, and an angle around
the link. As the link is transformed, all the vertices assigned to the vertex are
4642 | Chapter 17 character studio