5.5

294Motion User Guide
Controlling Simulation behaviors in Motion
The ideal use for behaviors (with the exception of Motion Tracking behaviors) is creating
fluid motion graphics that do not require specific timing. This is especially true with the
Simulation behaviors, which let you create sophisticated interactions among multiple
objects in your project with minimal editing.
Unlike Basic Motion behaviors, you cannot stop or change the motion of a Simulation
behavior in the Timeline. However, you can affect the rate of a Simulation behavior by
modifying its duration in the Timeline. You can also change the starting frame of the
behavior.
Because the Simulation behaviors mimic natural effects, such as Gravity, the laws of
inertia apply: An external force sets the object in motion, and that object stays in motion
even after the active force is no longer present. Changing the duration of a Timeline bar
for a Simulation behavior does stop the “active” force on the object but does not stop the
motion of the object. You can, of course, control Simulation behaviors by modifying their
parameters.
In the following image, the Orbit Around behavior is applied to the small blue circle. The
large orange circle is assigned as the object that the blue circle moves around. The red
animation path represents the motion of the small blue circle over its duration. The Orbit
Around behavior is the same duration as the large circle to which it is applied.
In the next image, the Orbit Around behavior is trimmed in the Timeline to a shorter
duration than the object to which it is applied. Notice the change in the shape of the
animation path: Where the Orbit Around behavior ends, the object (the small blue circle)
stops moving around its target and continues moving off the canvas. The Orbit Around
behavior—the active force—is no longer present, but the motion of the blue circle does
not stop.