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# controlPointBuffer

References a buffer containing curve control points.

```
var controlPointBuffer: MTL4BufferRange { get set }
```

## Discussion

Control points are interpolated according to the basis function you specify in [`curveBasis`](/documentation/Metal/MTL4AccelerationStructureCurveGeometryDescriptor/curveBasis).

You are responsible for ensuring each control is in a format matching the control point format [`controlPointFormat`](/documentation/Metal/MTL4AccelerationStructureCurveGeometryDescriptor/controlPointFormat)
specifies, as well as ensuring that the buffer address of the range is not zero.

---

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