Behavior Order of Operations
When combining different behavior types (such as Parameter and Simulation behaviors),
or combining behaviors and keyframes, it is 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 compositing order). For more information,
see
Reordering Behaviors
.
Important:
The order of operation is always in effect—regardless of the order in which
the behaviors are applied or the keyframes are added to a layer or group.
Use the following guidelines for animating layers with multiple behaviors and/or keyframes:
• When you animate a layer with keyframes and then apply a behavior, the effect of the
keyframes is evaluated first.
For example, if you animate the Rotation parameter of a layer using keyframes and
then apply a Rotational Drag (Simulation) behavior to the layer, the Rotational Drag
behavior slows the rotation of the layer. Motion is evaluating the keyframed rotation,
and then applying the drag (from the Simulation behavior) to the keyframed animation.
• When you animate a layer with any behavior, and then add keyframes, the effect of
the keyframes is evaluated first.
For example, if you animate a layer so it rotates in a clockwise direction using the Spin
behavior and then keyframe the Rotation parameter so the layer rotates in a
counterclockwise direction, the layer rotates in the counterclockwise direction. Although
the keyframes are added to the project after the Spin behavior, Motion evaluates the
keyframes first.
• When you animate a layer with a Simulation behavior and then apply another behavior,
the effect of the Simulation behavior is evaluated first.
For example, if you animate a layer using the Gravity (Simulation) behavior and then
apply a Throw (Basic Motion) behavior, the layer moves downward as specified by the
Gravity behavior and in the direction specified in the Throw behavior. Motion is applying
the value of the Throw behavior to the value of the Gravity behavior, creating the end
result.
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Chapter 9
Using Behaviors
• When you animate a layer with a behavior and then apply a Simulation behavior, the
Simulation behavior is evaluated before the first behavior (and might have no effect).
For example, if you animate the Rotation parameter of a layer using the Oscillate
(Parameter) behavior and then apply a Rotational Drag (Simulation) behavior to the
layer, the layer oscillates, but is not slowed by the Rotational Drag behavior. Motion is
evaluating 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 Motion’s order of operations.
For information on combining keyframes with behaviors, see
Combining Behaviors with
Keyframes
.