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# edgeCreaseIndices

A buffer containing vertex indices that describe edges to be treated as creases during surface subdivision.

```
var edgeCreaseIndices: (any MDLMeshBuffer)? { get set }
```

## Discussion

Each pair of entries in this buffer identifies an edge, between two connected vertices in the submesh, that is to be treated as a crease during surface subdivision. The buffer is sparse, containing only those vertex indices to be treated as creases. The corresponding entry in the [`edgeCreases`](/documentation/ModelIO/MDLSubmeshTopology/edgeCreases) buffer provides a sharpness value for the crease.

Because the number of entries in this buffer is likely to be different than the number of entries in any other vertex buffer, it shouldn’t be interleaved with other data in the mesh.

---

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