9

428 Chapter 12: Animation
scale animates the pa rent and the subtree attached
to the parent.
Anim ating a parent’s modifiers or creation
parameters has no effect on its descendants.
Moving the root parent moves the whole hierarchy.
Rotation of a parent object is p assed to a ll the child objects.
Animating a Child Object
With forward kinematics, a child is not constrained
by its link to a parent. You can move, rotate, and
scale children independent of their parents.
Moving the last child object does not affect any of the previous
objects in the hierarchy.
Rotating a child object in the middle of the hierarchy affec ts all
thedescendantsbutnoneoftheparents.
If you want to manipulate parent objects by
moving the last child in the chain, use inverse
kinematics (page 2–435).
Manipulating the Hierarchy
A child object inher its the t ransforms of its
parent, and the parent inherits the transforms of
its ancestors all the way up the hierarchy to the
root object. Because forward kinematics employs
this method of inheritance, you must position
and animate your hierarchies using a top-dow n
method.