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936 Chapter 14: Character Studio
Tip:
Physique skins are usually too large for
3ds Max to play them back in real t ime at 30
frames per second. However, speed improvements
in character studio will allow fluid motions of
many skinned meshes. When you attempt to
play back at 30 fps, 3ds Max may drop fra mes
during playback, which makes it hard to see
how Physique has animated the skin. Use the
Time Configuration dialog to tur n off real time
playback. The animation plays back more slowly
than usual, but it plays every frame.
Tip: You can also specify which elements of the
characters not to display in the viewports, and
thereby speed up redraw. See
Physique Level of
Detail Rollout (page 2–960)
.
For a skin attached to a complicated skeleton
such as a biped, you will almost always need to
correct some vertex assignments before the skin
animates correctly. Most often, you’ll do so simply
by adjusting t he envelope’s shape. See .
Envelopes and Ver tex
Assignments
Envelopes
Envelopes are Physique’s primary tool to control
skin deformation. Envelopes define an area of
influence about a single link in the hierarchy
and can be set to overlap adjacent links. Vertices
that fall in the overlap area of the envelopes are
weighted to produce smooth blending at joint
intersections. Each envelo pe comprises a pair
of inner and outer bounds, each with four cross
sections.
Envelopes
Deformable and Rigid Envelopes
There are two envelope types: deformable and
rigid.
• Deformable envelopes influence vertices they
encompass to follow the deformation spline
created through the hierarchy. Only the vertices
encompassed by deformable envelopes can be
affected by bulge angles or tendons.
• Vertices in a rigid envelope are linked to the
node (the bone) and move in an immobile
relationship to the link. Vert ices in a rigid
envelope, however, are deformed (blended) in
the overlap area of other envelopes. There is a
tw ist parameter in Link Sub-Object that can
be enabled in a rigid envelope. This all ows the
rigid envelope to twist along the length of the
link.