Apple Motion 4 - Manual (Page 364)

Nesting Groups and Layers
To help organize large groups of objects or to create certain kinds of special effects, you
can place one group inside of another. This gives you the flexibility to create a group
containing multiple objects, and then treat that entire group as a single object within
another group. You could go further and take that “parent” group, combine it with some
other groups, and treat that group as a single element, and so on. This is called nesting
or grouping.
There are many reasons why you might choose to nest your layers or groups. Doing so
allows you to simplify your composite, grouping objects and layers into fewer containers.
It also allows you to manipulate a group of objects as one. For example, you could take
the individual letters of your title (each animated on its own) and use nesting to animate
the group of them across the screen. You can also use grouping to create complex particle
systems. You can nest several objects into a layer, and use the entire layer as the emitter
cell. For more on particle systems, see
Working with Particles .
Note: You cannot use the Group command with objects that are in different groups.
To place one group inside another
1 Drag the group icon in the Timeline layers list onto the group inside of which you want
to nest it.
A black border highlights the destination group.
2 Release the mouse button.
The first group is now nested inside the second group.
You can also select the objects you want and choose Object > Group (or press
Command-Shift-G).
Note: There is no limit to the number of groups you can nest.
To return a nested group to its original state
µ
Select the nested group, then choose Object > Ungroup (or press Command-Option-G).
The nested group is restored into individual objects. Any group within another group
can be ungrouped.
To remove a group from within a nest
1 Click the group icon in the Timeline layers list.
2 Drag the group out of the existing parent group to the area above the highest track.
The position indicator appears.
3 Release the mouse button.
The group is restored to primary group status.
To delete a group or object track
1 Select the group or object in the Timeline layers list.
364 Chapter 8 Using the Timeline