Add, remove, and disable a Parameter behavior

A standard behavior is applied to an object and typically affects multiple parameters of that object. However, the special class of behavior known as the Parameter behavior is applied to a specific parameter of your choosing. In this way, you can modify a single parameter belonging to a filter, particle system, shape, text, or any other object in your project. You can even apply a Parameter behavior to a parameter of another behavior.

A Parameter behavior’s effect on an object depends on the parameter to which it is applied. For example, if you apply the Randomize parameter behavior to a particle emitter’s Position parameter, the emitter drifts randomly around the screen when the project plays. Applying the Randomize parameter behavior to a shape’s Scale parameter makes the shape randomly grow and shrink.

Important: Although you can apply a Parameter behavior to an object, the applied behavior does not affect the object until you select a specific parameter to apply the Parameter behavior to. A more direct way to apply a Parameter behavior is by using the shortcut menu in the Inspector.

Apply a Parameter behavior to a specific parameter of an object

Select the object to apply the Parameter behavior to.
Do one of the following:
- Control-click a parameter’s name in the Inspector, choose Add Parameter Behavior, then choose an item from the submenu.
- Click the parameter’s Animation menu (the downward arrow that appears when you move the pointer over the right side of a parameter row), choose Add Parameter Behavior, then choose an item from the submenu.
- Control-click a parameter in the HUD, choose Add Parameter Behavior from the shortcut menu, then choose an item from the submenu.
- Control-click a parameter in the Keyframe Editor parameter list, then choose a Parameter behavior from the shortcut menu.
  Use the pop-up menu above the Keyframe Editor to choose the parameters you want displayed in the Keyframe Editor. For more information, see Choose a curve view.

When you apply a Parameter behavior, the Behaviors Inspector opens.

Apply a Parameter behavior to an object

Do one of the following:
- Drag a Parameter behavior from the Library stack to an appropriate object in the Canvas, Layers list, or Timeline.
  Note: When applying a behavior to a camera or light, it’s usually easier to drag the behavior to a camera or light in the Layers list or Timeline than to the wireframe object in the Canvas.
- Select an object in the Canvas, Layers list, or Timeline, click the Add Behavior pop-up menu in the toolbar, then choose an item from the Parameter submenu.
The behavior is applied to the object, but no parameter is assigned to the behavior.
To assign a specific parameter to the Parameter behavior, do one of the following:
- Select the Parameter behavior in the Layers list, click the Apply To pop-up menu in the HUD, then choose a parameter from the submenu.
- Select the Parameter behavior in the Layers list, click the Apply To pop-up menu in the Behaviors Inspector, then choose a Parameter behavior from the submenu.
The parameter you chose appears in the Apply To text field.

Apply a Parameter behavior to a parameter of another behavior

Parameter behaviors can be applied to the parameters of other behaviors. For example, you can apply the Oscillate parameter behavior to the Drag parameter of the Orbit Around behavior. As a result, the orbital drag fluctuates, causing the object to fall toward the center of its orbit.

Canvas showing behavior's parameter being controlled by another behavior

Select a behavior that you’ve already applied to an object.
Do one of the following:
- Control-click a parameter’s name in the Inspector, choose Add Parameter Behavior, then choose an item from the submenu.
- Click the parameter’s Animation menu in the Inspector (the downward arrow that appears when you move the pointer over the right side of a parameter row), choose Add Parameter Behavior from the shortcut menu, then choose an item from the submenu.
- Control-click a parameter in the HUD, choose Add Parameter Behavior from the shortcut menu, then choose an item from the submenu.
- Control-click a parameter in the Keyframe Editor parameter list, then choose a Parameter behavior from the shortcut menu.
  Use the pop-up menu above the Keyframe Editor to choose the parameters you want displayed in the Keyframe Editor. For more information, see Choose a curve view.

Remove a Parameter behavior

Select a Parameter behavior in the Layers list, Timeline, Behaviors Inspector, or pop-up menu in the title bar of the HUD.
Do one of the following:
- Choose Edit > Delete.
- Press Delete.
  Note: You can also Control-click the behavior in the Layers list or Timeline, then choose Delete from the shortcut menu.

Note: If you save a Parameter behavior as a favorite, the parameter assignment is saved with the rest of that behavior’s settings. As a result, the saved behavior will affect the same parameters of any object it’s applied to.