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# init(_:)

Creates an object from a custom material’s specular property.

```
init(_ value: CustomMaterial.Specular)
```

## Parameters

`value`

The custom material’s specular property.

## Discussion

RealityKit automatically draws *specular highlights* for physically
based materials using the values of various properties, primarily
[`roughness`](/documentation/RealityKit/PhysicallyBasedMaterial/roughness-swift.property) and
[`metallic`](/documentation/RealityKit/PhysicallyBasedMaterial/metallic-swift.property). Specular
highlights are bright spots of reflected light that appear on shiny
objects.

![An illustration showing a sphere and a cube with rounded corners.](images/com.apple.RealityKit/PhysicallyBasedMaterial-Specular-swift-struct-init(_:)-1@2x.png)

While many real-world objects can be accurately and realistically
simulated with just the core PBR properties, you can create
additional realistic effects by augmenting the specular highlights.

This initializer creates a
[`PhysicallyBasedMaterial.Specular`](/documentation/RealityKit/PhysicallyBasedMaterial/Specular-swift.struct) object from the
specular property of a [`CustomMaterial`](/documentation/RealityKit/CustomMaterial).

---

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