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# radius

The radius of the sphere. Animatable.

```
var radius: CGFloat { get set }
```

## Discussion

The sphere is centered in its local coordinate system. For example, if you create a sphere whose radius is `5.0`, it extends from `-5.0` to `5.0` along each of the the x, y, and z-axes. A radius of zero or less creates an empty geometry.

You can animate changes to this property’s value. See [Animating SceneKit Content](/documentation/SceneKit/animating-scenekit-content).

---

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