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# setPositionOffsets(_:offset:)

Sets the buffer containing blend-shape position offsets.

```
func setPositionOffsets(_ buffer: any MTLBuffer, offset: Int) throws
```

## Parameters

`buffer`

The Metal buffer containing the blend-shape position offsets.

`offset`

The byte offset into `buffer` where the data begins.

## Discussion

The buffer must contain `targetCount × vertexCount` entries in the same
format as the input mesh’s `.position` attribute.

> Throws: If `offset` is out of bounds for `buffer`, or if the buffer is too small.

---

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