Applying Behaviors to Generators
As with all other objects in Motion, you can apply Basic Motion, Parameter, or Simulation
behaviors to a generator. This section describes applying the Randomize parameter
behavior to the Opacity parameter of the Star generator to create a flickering star.
To apply a Parameter behavior to the Star generator
1
Add the Star generator to your project and display the Generator Inspector.
2
In the Generator Inspector, move the pointer over the Spike Opacity parameter row.
The Animation menu (an inverted triangle) appears on the right side of the parameter
row.
946
Chapter 18
Working with Generators
3
Click the Animation menu for the Spike Opacity parameter, then choose Randomize from
the Add Parameter Behavior submenu.
The Randomize parameter behavior is applied to the Spike Opacity parameter, and the
Behaviors Inspector is displayed so you can adjust the Randomize parameters.
4
In the Behaviors Inspector, drag the Amount slider to the right to increase the
randomization effect.
5
In the transport controls (under the Canvas), click the Play button (or press the Space
bar).
947
Chapter 18
Working with Generators
Because the Randomize parameter behavior is applied to the opacity of the star spikes,
the star appears to flicker.
When a Parameter behavior is applied to a parameter of a generator, a behavior icon (a
gear) appears in the Generator Inspector in the row for the affected parameter. In this
example, the behavior icon appears in the Spike Opacity parameter row.
The gear icon indicates that
the parameter is being
controlled by a behavior.
To increase or decrease the effect of the flicker, you can modify the Randomize parameters
(in the Behaviors Inspector). To jump to the Randomize parameters from the Generator
Inspector, control-click Spike Opacity parameter name, then choose Randomize from the
shortcut menu.
For more information on using Parameter behaviors, see
Parameter Behaviors
.
948
Chapter 18
Working with Generators