Apple Motion 4 - Manual (Page 509)

Falloff Rate: This value determines how quickly the force of attraction between objects
affected by this behavior falls off. A low Falloff Rate value results in objects quickly getting
up to speed as they move toward the object of attraction. A high Falloff Rate causes
objects to accelerate much more slowly. When set to Exponential, the attraction falls off
more quickly than when set to Linear.
Influence: A slider that defines the radius of the circle of influence in pixels. Objects that
fall within the area of influence move toward the object of attraction. Objects that are
outside of the area of influence remain in place.
Drag: The default value for Orbit Around is 0, which results in a stable orbit. Any other
value causes the orbit to decay and the object to spiral into the object of attraction.
Include X, Y, and Z: Buttons that allow you to specify the space in which the orbit occurs.
For example, when X and Y are enabled, the object orbits in the XY plane. In the illustration
below, X and Y are selected in the Include parameter. The yellow motion paths represent
the motion of the white stars around the target object (the orange outlined star). The
light gray box represents the boundary of the group.
In the illustration below, Y and Z are turned on in the Include parameter. The white stars
move around the target object in the YZ plane.
509 Chapter 9 Using Behaviors