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# indexBufferOffset

The offset, in bytes, to the index data in the buffer.

```
var indexBufferOffset: Int { get set }
```

## Discussion

The offset needs to be a multiple of the index data type you configure with the [`indexType`](/documentation/Metal/MTLAccelerationStructureCurveGeometryDescriptor/indexType) property.
You also need to align the offset to both the index type’s size and the platform’s buffer alignment requirement.

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