Apple Motion 4 - Manual (Page 528)

3 In the Vortex HUD or Inspector, choose All Objects from the Affect pop-up menu.
When All Objects is chosen, all objects in the project—regardless of the group in which
they exist—are affected and move around the object to which the Vortex behavior is
applied.
Note: If you have a layer that is center-aligned with the layer that has the applied Vortex
behavior (the gradient background in this example), the aligned layer is not affected by
the Vortex behavior. Once you offset its position, the layer is influenced by the Vortex
behavior.
Using the Vortex behavior, there are two ways to create an animation in which only certain
objects (not every object in the project) swirl around the object with the applied Vortex
behavior:
• Set the Affect parameter to Specific Objects and select each layer that you want to swirl
around the target layer.
• Move the object with the applied Vortex behavior into the same group as the star
layers, and set the Affect parameter to Related Objects.
528 Chapter 9 Using Behaviors