About behavior order of operations
There’s no limit to the number of behaviors you can add to an object. When multiple behaviors are applied to a single object, they work together to create a final animated effect.
In general, each behavior applies a value to a specific parameter. The values generated by all behaviors that affect the same parameters are combined to create the end result. For example, if you apply the Throw, Spin, and Gravity behaviors to a single object, the Throw and Gravity behaviors combine to affect the position of the object. The Spin behavior affects the rotation of the object.
When combining different behavior types (such as Parameter and Simulation behaviors), or combining behaviors and keyframes, it’s important to understand the behaviors’ order of operations. Motion evaluates behaviors and keyframes in the following order:
Keyframes > Simulation behaviors > all other behaviors
Parameter behaviors are applied in the order in which they are added, from the bottom of the Layers list up (like the order of filters and the compositing order of image layers). For more information, see Copy, paste, move, and reorder behaviors.
Important: The order of operations is always in effect—regardless of the order in which the behaviors are applied or the keyframes added to a layer or group.
Use the following guidelines for animating objects with multiple applied behaviors or keyframes:
When you animate an object with keyframes and then apply a behavior, the effect of the keyframes is evaluated first.
For example, if you animate the Rotation parameter of an object using keyframes and then apply a Rotational Drag (Simulation) behavior to the object, Motion evaluates the keyframed rotation, and then applies the drag (from the Simulation behavior) to the keyframed animation.
When you animate an object with any behavior and then add keyframes, the effect of the keyframes is evaluated first.
For example, if you animate an object so it rotates in a clockwise direction using the Spin behavior and then keyframe the Rotation parameter so the object rotates in a counterclockwise direction, the object rotates in the counterclockwise direction. Motion always evaluates keyframes first.
When you animate an object with a behavior and then apply a Simulation behavior, the Simulation behavior is evaluated before the first behavior (and therefore may have no effect).
For example, if you animate the Rotation parameter of an object using the Oscillate (Parameter) behavior and then apply a Rotational Drag (Simulation) behavior to the object, the object oscillates, but is not slowed by the Rotational Drag behavior. Motion evaluates the Simulation behavior (Rotational Drag) before the Parameter behavior (Oscillate), applying the drag to a 0 value. There is no data for the Simulation behavior to affect.
Note: Although the Spin behavior appears in the Basic Motion category, Spin is treated as a Simulation behavior in the order of operations.
For information on combining keyframes with behaviors, see About combining behaviors with keyframes.