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# LightingModel

The lighting model used by a [`ShaderGraphMaterial.Program`](/documentation/RealityKit/ShaderGraphMaterial/Program-swift.struct).

```
enum LightingModel
```

## Overview

This must match the type of the surface output node in the [`ShaderGraph`](/documentation/RealityKit/ShaderGraph).
For example, a graph whose surface node is a PBR surface shader requires `.lit`.

## Topics

### Creating a lit model

[`static func lit(diffuseModel: LitLightingModel.DiffuseModel, specularModel: LitLightingModel.SpecularModel, isSubsurfaceScatteringEnabled: Bool, isMultiscatteringEnabled: Bool, isBentNormalEnabled: Bool, isClearcoatEnabled: Bool) -> LightingModel`](/documentation/RealityKit/LightingModel/lit(diffuseModel:specularModel:isSubsurfaceScatteringEnabled:isMultiscatteringEnabled:isBentNormalEnabled:isClearcoatEnabled:))

[`case lit(LitLightingModel)`](/documentation/RealityKit/LightingModel/lit(_:))

### Creating an unlit model

[`static func unlit(isTonemappingEnabled: Bool) -> LightingModel`](/documentation/RealityKit/LightingModel/unlit(isTonemappingEnabled:))

[`case unlit(UnlitLightingModel)`](/documentation/RealityKit/LightingModel/unlit(_:))

### Creating a hair model

[`static func hair() -> LightingModel`](/documentation/RealityKit/LightingModel/hair())

[`case hair(HairLightingModel)`](/documentation/RealityKit/LightingModel/hair(_:))

## Relationships

### Conforms To

[`Equatable`](/documentation/Swift/Equatable)

[`Hashable`](/documentation/Swift/Hashable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Sendable`](/documentation/Swift/Sendable)

---

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