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# geometryType

The type of geometric primitives described by the submesh’s index buffer.

```
var geometryType: MDLGeometryType { get }
```

## Discussion

This property determines how the sequence of indices in the submesh’s index buffer should be interpreted for rendering. For example, if the geometry type is [`MDLGeometryType.triangles`](/documentation/ModelIO/MDLGeometryType/triangles), each triangle to be rendered comes from an independent set of three indices, but if the geometry type is [`MDLGeometryType.triangleStrips`](/documentation/ModelIO/MDLGeometryType/triangleStrips), triangles to be rendered can come from overlapping sets of indices in the sequence. If the geometry type is [`MDLGeometryType.variableTopology`](/documentation/ModelIO/MDLGeometryType/variableTopology), the [`topology`](/documentation/ModelIO/MDLSubmesh/topology) property describes the non-uniform layout of the index buffer.

---

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