---
title: emission
framework: scenekit
role: symbol
role_heading: Instance Property
path: scenekit/scnmaterial/emission
---

# emission

An object that defines the color emitted by each point on a surface.

## Declaration

```swift
var emission: SCNMaterialProperty { get }
```

## Discussion

Discussion You can use an emissive map texture to simulate parts of a surface that glow with their own light. SceneKit does not treat the material as a light source—rather, the emission property determines colors for a material independent of lighting. (To create an object that appears to glow, you may wish to combine a geometry with an emissive map and additional SCNLight objects added to the scene.) By default, the emissive property’s contents object is a black color, causing the property to have no visible effect. Setting the emissive property’s contents to any solid color adds a uniform color to the material independent of lighting. To create a selective glow effect, set the property’s contents to an image or other texture-mapped content whose glowing areas use bright colors and whose other areas use darker colors. In the darker-color portions of the emissive map (and portions with reduced opacity), the other visual properties of the material contribute to its appearance under scene lighting. The figure below shows a material (with a texture for its diffuse property) before and after providing an emissive map image.

## See Also

### Related Documentation

- [specular](scenekit/scnmaterial/specular.md)
- [reflective](scenekit/scnmaterial/reflective.md)
- [multiply](scenekit/scnmaterial/multiply.md)
- [ambient](scenekit/scnmaterial/ambient.md)
- [transparent](scenekit/scnmaterial/transparent.md)

### Visual Properties for Special Effects

- [normal](scenekit/scnmaterial/normal.md)
- [displacement](scenekit/scnmaterial/displacement.md)
- [selfIllumination](scenekit/scnmaterial/selfillumination.md)
- [ambientOcclusion](scenekit/scnmaterial/ambientocclusion.md)