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# init(indexOffset:indexCount:topology:materialIndex:bounds:)

Creates a low-level mesh part.

```
init(indexOffset: Int = 0, indexCount: Int = 0, topology: MTLPrimitiveType = .triangle, materialIndex: Int = 0, bounds: BoundingBox)
```

## Parameters

`indexOffset`

The offset, in bytes, of the first index.

`indexCount`

The number of indices to use for this part.

`topology`

The geometric primitive to use when rendering this part.

`materialIndex`

The material index this part associates with.

`bounds`

The model-space bounding box of the part.

---

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