---
title: emissiveColor
framework: realitykit
role: symbol
role_heading: Instance Property
path: realitykit/custommaterial/emissivecolor-swift.property
---

# emissiveColor

The color of light this material emits.

## Declaration

```swift
var emissiveColor: CustomMaterial.EmissiveColor { get set }
```

## Discussion

Discussion With physically based rendering (PBR), you can give entities in RealityKit the appearance of emitting light. Use this property to simulate real-world objects that glow, such as objects with LEDs or computer screens. To enable light emission from a material, set emissiveIntensity to a value greater than zero, then specify a color (other than black) using this property. You can specify a single emissive color for the entire material, or use a UV-mapped image texture to use different colors for different parts of the entity. With custom materials, RealityKit doesn’t use emissiveColor automatically to render your entity. Call params.surface().set_emissive_color() from your surface shader, otherwise RealityKit renders no light emission. The following example assigns a tint color to the emissiveColor property, without a texture: self.emissiveColor = PhysicallyBasedMaterial.EmissiveColor(color: .red) This next example uses a texture to specify the emissiveColor property: if let emissiveResource = try? TextureResource.load(named: "entity_emissive") {     let emissiveMap = MaterialParameters.Texture(emissiveResource)     material.emissiveColor = .init(texture: emissiveMap) } This Metal code shows how to access the emissive color tint in your shader functions: half3 emissiveTint = (half3)params.material_constants().emissive_color(); The following Metal code demonstrates how to sample the emissive color texture for the current fragment: // Get the entity's primary texture coordinates. float2 uv = params.geometry().uv0();

// Flip the y-axis. You only need to do this for entities you load from // USDZ or .reality files. uv.y = 1.0 - uv.y;

// Sample the emissive color texture to get the value for this fragment. auto tex = params.textures(); half3 emissiveColor = (half3)tex.emissive_color()     .sample(textureSampler, uv).rgb;

## See Also

### Setting the core properties

- [baseColor](realitykit/custommaterial/basecolor-swift.property.md)
- [roughness](realitykit/custommaterial/roughness-swift.property.md)
- [metallic](realitykit/custommaterial/metallic-swift.property.md)
- [normal](realitykit/custommaterial/normal-swift.property.md)
- [ambientOcclusion](realitykit/custommaterial/ambientocclusion-swift.property.md)
- [specular](realitykit/custommaterial/specular-swift.property.md)
- [clearcoat](realitykit/custommaterial/clearcoat-swift.property.md)
- [clearcoatRoughness](realitykit/custommaterial/clearcoatroughness-swift.property.md)
- [clearcoatNormal](realitykit/custommaterial/clearcoatnormal-swift.property.md)