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302 Chapter 12: Animation
changing the length and angle of the tangent
handle.
Lock button—Changes one Custom tangent by
changing the other an equal but opposite amount.
For example, if you click the Lock button and the
In va lue is 0.85, then the Out value is -0.85.
Normalize Time—Averages the position of the keys
in time and applies them to any consecutive blocks
of selec ted keys. Useful if you have an object that
speeds up and slows down repeatedly, and you
want to smooth out the motion.
Constant Velocity—When on, interpolates values
between the key and the next one so that the object
moves at a constant velocity across that curve
segment. Available only with certain controller
types, such as Bezier.
Fr ee Han d le —Used for automatically updating the
length of the tangent handle. When this is turned
off, the length of the tangent is at a fixed percentage
from its neighboring key . As you move a key , the
handles adjust to stay the same percentage away
fromtheneighboringkeys.Whenthisisturned
on, the handle lengths are based on t ime lengths.
Animation Controllers
Track View > Select a track in the Track V iew hierarchy.
> Track View menu bar > Controller menu > Assign >
Choose a controller in the dialo g.
Animation menu > Constraints/Transform
Controllers/Position Controllers/Rotation
Controllers/Sc a le Controllers> Choose a controller.
Select an object. > Motion panel > Assign Controller
rollout > Select a track. > Assign Controller > Choose a
controller in the dialog.
Cont rollers, like constraints (page 2–375) ,handle
the animation tasks in a scene, including:
•Storinganimationkeyvalues
• Storing procedural animation settings
• Interpolating between animation key values
An object or parameter doesn’t receive a controller
until you animate it. As soon as you change an
animatable parameter with Auto Key on, or
add a
key (page 2–537)
in Tr ack View - Dope Sheet (page
2–483)
, the software assigns a controller to the
parameter.Thesoftwarechoosesadefaulttypefor
the controller , depending on the animation. You
can change the default controller to another type.
The animation controllers are organized in the
following categories:
• Float control lers: for animating floating-point
values
• Point3 controllers: for animating
three-component values such as colors or 3D
points
• Position controllers: for animating positions
of objects and selection sets
• Rotation controllers: for animating rotation of
objects and selection sets
• Scale controllers : for animating the scale of
objects and selection sets
• Tra n sf orm contr olle rs: for animating general
transforms (position, rotation, and scale) of
objects and selection sets
To change an assigned controller, u se
Cont roller
> Assign (page 2–523)
in Track View or in the
Motion panel (page 3–817) .
The controllers and constraints are:
Attachment Constraint (page 2–376)
Audio Controller (page 2–303)
Bezier Controllers (page 2–305)
Barycentric Morph Controller (page 2–304)
Block Controller (page 2–307)
Boolean Controller (page 2–310)