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# primitiveDataElementSize

Sets the size, in bytes, of the data for each primitive in the primitive data buffer [`primitiveDataBuffer`](/documentation/Metal/MTL4AccelerationStructureGeometryDescriptor/primitiveDataBuffer) references.

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

## Discussion

This size needs to be at most [`primitiveDataStride`](/documentation/Metal/MTL4AccelerationStructureGeometryDescriptor/primitiveDataStride) in size and a multiple of 4 bytes.

This property defaults to 0 bytes.

---

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