Motion 5 - Combining Behaviors and Keyframes

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Combining Behaviors and Keyframes

Because it is possible to add keyframes to an object that can already have a behavior (or
many behaviors) applied, these two methods might conflict. For example, you might
apply a Throw behavior toward the upper left, and at the same time add keyframes that
instruct the object to move to the right.

Behavior motion path

Keyframe animation path

The way Motion handles this sort of conflict is to add the instructions together, giving
you a combination of the two sets of instructions. In the above example, the
behavior-driven object moves toward the upper left, but doesn’t get as far, because
keyframes are pushing it in an opposing direction.

Combined animation path

The larger the Throw velocity rate, the more the behavior overpowers the keyframes, and
vice versa.

You can use this method to enhance and control the effects of behaviors. For example,
you can apply a Gravity behavior that causes an object to fall toward the bottom of the
frame, then keyframe the object’s position to move across the screen from left to right.
In this way, you create the effect of the object falling as it moves.

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Chapter 12

Keyframes and Curves

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Or you can apply a Fade In/Fade Out behavior, but use keyframes on the object’s Opacity
parameter to limit the maximum opacity to 80%. The clip fades in and out, and you can
continue to modify the behavior’s attributes, but the object never exceeds the opacity
value set by the keyframes.

One method for handling behaviors and keyframes is to convert behaviors to keyframes.
For more information, see

Converting Behaviors to Keyframes

.