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# spreadingAngle

The range, in degrees, of randomized initial particle directions. Animatable.

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

## Discussion

Setting a nonzero value for this property randomizes the direction specified by the [`emittingDirection`](/documentation/SceneKit/SCNParticleSystem/emittingDirection) or [`birthDirection`](/documentation/SceneKit/SCNParticleSystem/birthDirection) property. For example, at the default value of `0.0` degrees, all particles emit in the same direction. Increasing the spreading angle to `30.0` degrees allows particles to emit in any direction within a space shaped like a cone whose central angle is 30°.

This property has no effect if the [`birthDirection`](/documentation/SceneKit/SCNParticleSystem/birthDirection) property value is [`SCNParticleBirthDirection.random`](/documentation/SceneKit/SCNParticleBirthDirection/random).

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

---

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