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1104 Chapter 14: character studio
4.
Select the links of the upper lip, and click Lock
Assignments.
5. Region-select vertices of the upper lip, and click
Remove From Link.
6. Select links of the lower lip, and click Lock
Assignments.
Physique and Modifier s
Combining Physique with Other
Modifiers
Although you can apply Physique to an object
w ith modifiers, this can affect performance. If
you use other animated modifiers in combination
with Physique, this reduction is unavoidable. If the
other modifiers are not animated, you can collapse
the stack to remove modifiers prior to Physique.
This can significantly improve performance.
HowPhysiquereevaluatesverticescomingupthe
stack depend s on the stack update options.
Stack Update Options
InPhysique,therearethreestackupdateoptions
available from the Physique Le vel of D etail rollout
(page 2–1108) to determine how Physique handles
animated vertices coming up the modifier stack.
Add Change
Add Change adds in the changes from the
stack and then applies mesh deformation. No
vertexremappingorreassigningisdone. This
isthedefaultoption,andusuallywillgiveyou
the deformation that you want. There is no
performance degradation from Physique.
Remap Locally
Remap Locally resets vertex position on the spline
used for bending and the link position used to
interpolate twist. Use this option when vertices
are sliding along the length of the spline, and you
want them to bend and twist based on t he spline
position but don’t want the weights to change.
Reassign Globally
Reassign Globally does a complete vertex reassign
for each frame. Use this option w hen vertices
are moving to different envelopes and you want
them reass igned to the new envelopes. This option
should rarely be used. The only reason would be if
vertices are sliding along a link and you want the
tw ist to be interpolated based on the new posit ion.
Using Physique with Changing G eometry
Physiq ue can effectively handle dynamically
changing geometry. That is, if the geometry
coming through the modifier stack to Physique
changes, Physique dynamically adjusts to
accommodate the changes to the geometry, while
maintaining its own parameter settings, including
manual vertex assi gnments. This is why, when
using Opt imize, you can effectively change the
resolution of the geometry deformed by Physique.
Only in situations where the changes dramatical ly
increase the density of data is there ever a need
to manually adjust vertex assignments. Physique
remembers your manual vertex assi gnments, and
uses these assi gnments to reassign vert ices when
the geometry changes.
Physique and Free Form
Deformations (FFDs)
Physique can be applied to a Free-Form
Deformation (FFD) space warp, w hich in turn
can animate a mesh that is bound to the FFD. For