Apple Motion 3 - Manual (Page 472)

472 Chapter 5 Using Behaviors
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 turned on 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.
Pole Axis: This parameter becomes available when the X, Y, and Z axes are enabled in
the Include parameter. Because all points are at a fixed distance from the target or
attractor object (the Pole Axis), the object can be visualized on a sphere of all possible
orbits, with the target object at the center of the sphere. The Pole Axis defines the two
points on the sphere that the orbit must pass through.