---
title: radiusBuffer
framework: metal
role: symbol
role_heading: Instance Property
path: metal/mtlaccelerationstructurecurvegeometrydescriptor/radiusbuffer
---

# radiusBuffer

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

## Declaration

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

## Discussion

Discussion The buffer contains values that are greater than or equal to 0.0 in the format you configure with the radiusFormat property. This property needs to have a non-nil value when you build an acceleration structure.