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# radiusBuffer

A buffer that contains the curve radius for each control point.

```
var radiusBuffer: (any MTLBuffer)? { get set }
```

## Discussion

The buffer contains values that are greater than or equal to `0.0` in the format you configure with the [`radiusFormat`](/documentation/Metal/MTLAccelerationStructureCurveGeometryDescriptor/radiusFormat) property.
This property needs to have a non-nil value when you build an acceleration structure.

---

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