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# setBufferOffset(_:index:)

Changes where the data begins in a buffer already bound to the buffer argument table.

```
func setBufferOffset(_ offset: Int, index: Int)
```

## Parameters

`offset`

Where the data to bind begins, in bytes, from the start of the bound buffer.

`index`

The argument table entry to change.

## Discussion

Prefer calling this method to unbinding and then rebinding data.

For buffers binding to an argument using the `device` address space, align the offset to the data type’s size. The maximum size for an offset is `16` bytes.

For buffers in the `constant` address space, the minimum alignment depends on the hardware running your app. See the [Metal feature set tables (PDF)](https://developer.apple.com/metal/Metal-Feature-Set-Tables.pdf) for information on each Apple GPU family.

---

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