Work with parent and child layers – Adobe After Effects CS3 User Manual
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AFTER EFFECTS CS3
User Guide
158
Work with parent and child layers
To synchronize changes to layers by assigning one layer’s transformations to another layer, use parenting. After a layer
is made a parent to another layer, the other layer is called the child layer. When you assign a parent, the child layer’s
transform properties become relative to the parent layer instead of to the composition. For example, if a parent layer
moves 5 pixels to the right of its starting position, then the child layer also moves 5 pixels to the right of its position.
Parenting is similar to grouping; transformations made to the group are relative to the parent’s anchor point.
Parenting affects all transform properties except Opacity: Position, Scale, Rotation, and (for 3D layers) Orientation.
A layer can have only one parent, but a layer can be a parent to any number of layers in the same composition.
You can animate child layers independent of their parent layers. You can also parent using null objects, which are
hidden layers.
You cannot animate the act of assigning and removing the parent designation—that is, you cannot designate a layer
as a parent at one point in time and designate it as a normal layer at a different point in time.
When you create a parenting relationship, you can choose whether to have the child take on the parent’s transform
property values or retain its own. If you choose to have the child take on the parent’s transform property values, the
child layer jumps to the parent’s position. If you choose to have the child retain its own transform property values,
then the child stays where it is. In both cases, subsequent changes to the parent’s transform property values are
applied to the child. Similarly, you can choose whether the child jumps when the parenting relationship is removed.
Dragging the pick whip in the Timeline panel to designate the planet layer as the parent to the saucer layer
Note: To show or hide the Parent column in the Timeline panel, choose Columns > Parent from the Timeline panel menu.
Angie Taylor provides a character animation tutorial that shows how to use parenting and expressions:
Guy Chen provides a simple project that demonstrates the animation of several 3D layers arranged as a cube,
controlled by a parent null layer:
•
To parent a layer, in the Parent column, drag the pick whip from the layer that is to be the child layer to the layer
that is to be the parent layer.
•
To parent a layer, in the Parent column, click the menu of the layer that you want to be the child, and choose a
parent layer name from the menu.
•
To remove a parent from a layer, in the Parent column, click the menu of the layer to remove the parent from, and
choose None.
•
To extend the selection to include all child layers of a selected parent layer, right-click (Windows) or Control-click
(Mac OS) the layer in the Composition or Timeline panel, and choose Select Children.
•
To make a child layer jump when a parent is assigned or removed, hold down Alt (Windows) or Option (Mac OS)
as you assign or remove the parent.
•
To remove a parent from a layer (i.e., set Parent to None), Ctrl-click (Windows) or Command-click (Mac OS) the
child layer's parenting pickwhip in the Timeline panel. Alt+Ctrl-click (Windows) or Option+Command-click
(Mac OS) the child layer's parenting pickwhip to remove the parent and cause the child layer to jump.