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# inputPrimitiveTopology

The type of primitive topology the pipeline renders.

```
var inputPrimitiveTopology: MTLPrimitiveTopologyClass { get set }
```

## Discussion

Your app needs to specify this value when layered rendering is enabled.

The default value is `MTLPrimitiveTopologyClassUnspecified`.

## See Also

[`renderTargetArrayLength`](/documentation/Metal/MTLRenderPassDescriptor/renderTargetArrayLength)

The number of active layers that all attachments need to have for layered rendering.


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