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392 Chapter 12: Animation
An Orientation constraint causes an object’s
orientation to follow the orientation of an object
or averaged orientation of several objects.
An Orientation Constrained object can be any
rotatable object. When constrained it will inherit
its rotation from a target object. Once constrained
you can not rotate the object manually. You
maymoveorscaletheobjectaslongasitsnot
constrained in a manner that effects the object’s
position or sca le controller.
Thetargetobjectcanbeanytypeofobject.The
rotation of a target object drives the constrained
object. Targets can be animated using any of the
standard translat ion, rotation, and scale tools.
Multiple Tar gets and Weighting
A constrained object can be influenced by several
target objects. When using multiple targets, each
targethasaweightvaluethatdefinesthedegreeby
which it influences the constrained object, relative
to other targets.
Using Weig ht is meaning f u l (and available) only
w ith multiple targets. A value of 0 means the
target has no influence. Any value greater than
0 c auses the target to influence the constr ained
object relative to other targets’ Weight sett i ngs.
For example, a target with a Weight value of 80 will
have twice the influence of a target with a Weight
value of 40.
Pr ocedur es
To assign an Or ientation constraint:
1.
Select the object you want to constrain.
2. Choose Animation menu > Constraints >
Orientation Constraint.
3. Select target object.
To a ccess the Or ientation constraint ’s para meters
through the M otion pa nel:
1.
Select the Orientation-constrained object.
2. On the Motion panel > Rotation list,
double-click Orientation Controller.
The Orientation constraint parameters are
located on the Orientation Constraint rollout.
To edit weight values:
1.
Select the constrained object.
2. Open the Motion panel > Or ientation
Constraint rollout.
3. Click a target from the l ist.
4. UsetheWeightspinnerorenteranumerical
valuetosettheweightvalue.
To animate weight values:
1.
Select the constrained object.
2. Open the Motion panel > Or ientation
Constraint rollout, and choose a target from
the list.
3. Tur n on the Auto Key button.
4. UsetheWeightspinnerorenteranumerical
valuetosettheweightvalue.