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# lightSize

The radius of the spotlight’s emitting surface, in meters.

```
var lightSize: Float { get set }
```

## Discussion

Larger values widen the penumbra and lengthen the transition between
fully-shadowed and fully-lit regions, approximating the way an area
light of that radius would shade a scene. The default value is `0.1`.

This property has no effect when [`quality`](/documentation/RealityKit/SpotLightComponent/Shadow/quality) is [`low`](/documentation/RealityKit/SpotLightComponent/Shadow/QualityMode/low),
which always produces a hard-edged shadow.

---

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