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# usesSceneTimeBase

For animations attached to SceneKit objects, a Boolean value that determines whether the animation is evaluated using the scene time or the system time.

```
var usesSceneTimeBase: Bool { get set }
```

## Discussion

If the value of this property is <doc://com.apple.documentation/documentation/Swift/true>, animation timing is governed by the currentTime property of the view, layer, or custom renderer responsible for drawing the scene. The default value is <doc://com.apple.documentation/documentation/Swift/false>.

To attach animations to SceneKit objects, see <doc://com.apple.documentation/documentation/SceneKit/SCNAnimatable>.

---

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