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# StartAnimationAction

An action that plays an asset’s animation.

## Discussion

If the asset defines an animation, this action runs it on every prim in [affectedObjects](/documentation/USD/affectedobjects).

### Declaration

```other
class Preliminary_Action "StartAnimationAction"
```

## Topics

### Properties

[info:id](/documentation/USD/info-id)

The action’s unique identifier.

[affectedObjects](/documentation/USD/affectedobjects)

A list of prims that respond to the notification.

[start](/documentation/USD/start)

The moment to begin an animation.

[duration](/documentation/USD/duration)

The amount of time that the objects face the camera.

[reversed](/documentation/USD/reversed)

A Boolean value that determines the clip playback direction.

[animationSpeed](/documentation/USD/animationspeed)

A factor to apply to the animation speed.

[reverses](/documentation/USD/reverses)

A Boolean value that indicates whether the animation plays from beginning to end, then again from end to beginning.


---

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