2009

Properties of the Link constraint include:
■ The Link constraint respects the link inheritance settings applied to the
child object.
■ The object using a Link constraint is not a true child object. It does not
appear in the subtree of any linked parent objects.
■ Objects with Link constraint do not participate in IK solutions.
Link to World
You can also link an object to the world using the Link to World button. This
will keep the object stationary without the use of a dummy object. Just click
Link to World and the world is automatically entered as a Target.
Key Modes
You can choose between three different key modes, which determine how
keyframes are written on the linked objects as part of the link constraint. These
options provide the following:
No Key Mode No keys are created any of the objects involved. No keys will
be visible in the track bar.
Key Nodes Sets keys for some of the objects. Child applies keys to the child
object only. Parents applies keys to both parents and the child object.
Key Entire Hierarchy This applies keyframes to the chosen nodes and their
entire hierarchies. Child keys the chosen object and the nodes in its hierarchy
up to the world. Parents keys both parents and the child and all three
hierarchies up to the world.
Side Effects of the Link Constraint
The Link constraint works to keep a child object from jumping position at
the time when the link changes from one parent to another parent.
Considering the previous example, the following should hold true:
■ During frames 0 to 50 the ball remains constant relative to the first hand.
■ During frames 50 to 100 the ball remains constant relative to the second
hand.
■ At frame 50, the time when link control changes, the ball does not jump.
Animating with Forward Kinematics | 3367