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# specularCubeDimension

The dimension of the computed specular cubemap for material reflections.

```
var specularCubeDimension: Int?
```

## Discussion

If `nil`, the environment resource uses the source cubemap’s dimensions.

A value lower than that of the cubemap helps to reduce the memory footprint
in scenes where you view skybox details through specular reflections.

> Note: The specular cube dimension clamps to the source
> cubemap’s dimensions if it exceeds them.

---

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