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398 Chapter 12: Animation
Align to U—
Aligns the local Z axis of the controlled
object with the surface normal of the surface
object, and the X axis with the U axis of the surface
object.
Align to V —Aligns the local Z axis of the controlled
object with the surface normal of the surface
object, and the X axis is aligned with the V axis of
the surface object.
Flip—Flips the alignment of the local Z axis of the
controlledobject.Thischeckboxisnotavailableif
No Alig nment is tur ned on.
Pa th Co nst r a int
Animation menu > Constraints > Path Constraint
Path constraint positions the service platform along the side
of the bridge.
A path constraint restricts an object’s movement
along a spline or at an averaged distance between
multiple splines.
A path target can be any type of spline. The spline
curve (target) defines a path of motion for the
constrained object. Targets can be animated using
any of the standard translation, rotat ion, scale
tools. Setting keys on the path’s sub object level,
such as vertex, or segment will animate the path
whileaffectingtheconstrainedobject.
Multiple Ta rgets and Weighting
A constrained object can be influenced by several
target objects. When u sing multiple t argets, each
target has a weight value that defines the degree by
which it influences the constrained object, relative
to other targets.
UsingWeightismeaningful(andavailable)only
w ith multiple targets. A va lue of 0 means the
target has no influence. Any value greater than
0 causes the target to influence the constrained
object relative to other t argets’ Weight sett ings.
For example, a target with a Weight va lue of 80 will
have twice the influence of a target with a Weight
value of 40.
Procedures
To assign a Path constraint:
1.
Create a Sphere with a radius of 10 and a Circle
with a radius of 60.
2. With the Sphere selected, choose Animation
menu > Constraints > Path Constraint.
Youarenowinselecttargetmode.
3. In the viewport, select the Circle shape.
To access the Path constraint’s parameter s through
the Motion panel:
1.
Select the Sphere.
2. Open the Motion panel.
3. In the PRS Parameters rollout, click the Po sition
button.
ThePathconstraint’ssettingsarelocatedinthe
Path Parameters rollout.
To as sign a Path constrai nt thr ough the M otion
pan el:
1.
Create a Sphere with a radius of 10 and a Circle
with a radius of 60.
2. Select the Sphere.
3. On the Motion p anel and click Parameters.