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# bounds

The bounds of this mesh instance, in model space, or `nil` to derive bounds from the mesh part.

```
final var bounds: BoundingSphereBox? { get set }
```

## Discussion

Assign a value to override the mesh part’s bounds — for example, when using instancing
to place instances across a wider area than the base mesh part covers, or when a
geometry modifier displaces vertices beyond the mesh part’s recorded bounds.

---

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