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# LowLevelMaterialResource.Descriptor

The geometry modifier, surface shader, and lighting function for a material.

```
struct Descriptor
```

## Topics

### Creating a descriptor

[`init(geometry: LowLevelMaterialResource.GeometryModifier, surface: LowLevelMaterialResource.SurfaceShader, lighting: LowLevelMaterialResource.LightingFunction)`](/documentation/RealityKit/LowLevelMaterialResource/Descriptor/init(geometry:surface:lighting:))

Creates a descriptor from the three shader stages.

### Configuring the shaders

[`var surface: LowLevelMaterialResource.SurfaceShader`](/documentation/RealityKit/LowLevelMaterialResource/Descriptor/surface)

The fragment-stage surface shader.

[`var geometry: LowLevelMaterialResource.GeometryModifier`](/documentation/RealityKit/LowLevelMaterialResource/Descriptor/geometry)

The vertex-stage geometry modifier.

### Instance Properties

[`var lighting: LowLevelMaterialResource.LightingFunction`](/documentation/RealityKit/LowLevelMaterialResource/Descriptor/lighting)

The lighting evaluation function.

## Relationships

### Conforms To

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

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

---

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