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# topology

A description of how the non-uniform layout of the submesh’s index buffer defines the shape of the mesh.

```
var topology: MDLSubmeshTopology? { get set }
```

## Discussion

Submeshes with non-uniform topology can also contain edge and vertex crease information for use by the [`newSubdividedMesh(_:submeshIndex:subdivisionLevels:)`](/documentation/ModelIO/MDLMesh/newSubdividedMesh(_:submeshIndex:subdivisionLevels:)) method.

---

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