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# emission

The color emitted as radiance from a material’s surface.

```
var emission: MDLMaterialProperty { get }
```

## Discussion

A renderer (or other software component processing the material) might not treat the emission channel of a material as a light source illuminating the scene. Instead, an emission channel prevents affected areas of a surface from being darkened by other aspects of lighting and shading.

The default emission color is light gray (80% white).

---

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