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Envelopes 937
Deformable envelopes (above); Rigid envelopes ( below)
Typically, you use deformable envelopes when
you attach a mesh to the biped pelvis to produce
a soft, flexible skin. Later you reassign certain
links, such as the character’s head, to the rigid
envelope to minimize the deformation. For special
cases, you can turn on both deformable and r igid
envelopesforthesamelink.Thisadvancedfeature
allows you to aver age the effect of the two t ypes of
skin deformation for additional firmness in the
skin. The forearms and legs are sometimes good
candidates for this.
Blending Between Links
Blending between e nvelope s controls deformation .
Blending controls specify the influence of
overlapping envelopes on vertices cont ained
within the overlap area. By the actua l shape of
adjacent env elopes, you can con trol the degree of
influence each has on blending at the overlap area.
You can further control the number of envelopes
that participate in the blending effect, or whether
no blending takes place at all. Where you specify
no blending, a vertex in an overlap area is
influenced by a single link only.
Inner a nd Outer B ounds
Inner and outer bounds
Where a vertex fa lls within the inner and outer
bounds determines the percent of influence of the
attached link(s). Vertices that fall within the inner
bound have a weight of 1. Vertices that fall between