Apple Motion 4 - Manual (Page 475)

2 Control-click the parameter, then choose MIDI from the shortcut menu.
The MIDI parameters are displayed in the Behaviors tab. By default, Control Type is set
to Learning.
Like all other Parameter behaviors, the Apply To field displays the parameter to which
the behavior is applied.
3 On your MIDI device, tweak the control (such as the knob, dial, or key) that you want to
use as the controller for the Opacity parameter.
Note: When in Learning mode, the first control adjusted on the MIDI device is set as the
control. To reset the selected controller, choose Learning from the Control Type pop-up
menu, and adjust another control on the MIDI device.
The identification number of the MIDI control is displayed in the ID field. The value range
of the control is 0 to 127, the default MIDI control value.
Because an object’s opacity can only fall between 0 (completely transparent) to 100
(completely opaque), the default MIDI values are sufficient to adjust the parameter.
To use the MIDI parameter behavior to adjust an object’s rotation
1 Select an object, then select the Rotation parameter in the Properties tab of the Inspector.
2 Control-click the parameter, then choose MIDI from the shortcut menu.
3 On your MIDI device, tweak the control (knob, dial, key, and so on) that you want to use
as the controller for the Rotation parameter.
As mentioned above, the default Value range is 0 to 1. Because the Rotation value of an
object can be much larger, you can use the Scale parameter to multiply the Value range.
4 To give the control more sensitivity, increase the Scale value.
Negate
Inverts the value of each keyframe and behavior effect in the parameter to which it’s
applied by multiplying the parameter by –1. The Negate behavior basically flips each
parameter value to its opposite. Animation paths are flipped, rotation is reversed, and
any effect’s parameter is changed to its opposite.
475 Chapter 9 Using Behaviors