Emissive strength

Emissive strength scales a surface’s emitted radiance beyond the core emissive color range for HDR highlights and bright displays.

CompareEmissiveStrength compares emission levels; EmissiveStrengthTest increases the multiplier across a row of cubes. Select Sample model to compare the supplied examples. Drag to orbit and scroll to zoom.

Sample model

GitHub

Loading examplePreparing GPU resources…

PBRMaterial reference

PBRMaterial from @luma.gl/experimental is a typed engine Material backed by the shared pbrMaterial shader module. Its material fields are defined by PBRMaterialUniforms from @luma.gl/shadertools. Pass them through createPBRMaterial(device, {uniforms}) or update them with material.setProps({pbrMaterial: {...}}).

The fields below are optional. Defaults are the shared shader defaults; imported assets can supply other values.

Field	Type	Default	Description
`emissiveFactor`	`Readonly<Vector3 \| NumberArray3>`	`[0, 0, 0]`	Linear RGB emissive color.
`emissiveStrength`	`number`	`1`	Nonnegative multiplier; values above 1 allow HDR emission.
`emissiveMapEnabled`	`boolean`	`false`	Enables emissive texture sampling.

PBRMaterialBindings

Texture bindings accept Texture | null. createPBRMaterial() derives the map-enabled flag; the model still needs the corresponding shader define.

Binding	Model define	Description
`pbr_emissiveSampler`	`HAS_EMISSIVEMAP: true`	sRGB emissive RGB, multiplied by factor and strength.

Supporting APIs

createPBRMaterial

createPBRMaterial(device, {uniforms, bindings, factory}) from @luma.gl/experimental returns a PBRMaterial. uniforms sets the fields listed above, bindings supplies material textures, and the optional factory shares a compatible binding schema across materials. The helper derives map-enabled flags from the supplied bindings; explicit uniform values take precedence.

MaterialFactory

createPBRMaterialFactory(device) from @luma.gl/experimental creates a reusable engine MaterialFactory configured with the pbrMaterial shader module. Pass this factory to createPBRMaterial() when creating several compatible materials.

Material

Material from @luma.gl/engine owns material uniforms and texture resources. setProps({pbrMaterial: {...}}) updates uniform values. Pass the material to a compatible Model through its material prop; models sharing it observe the same updates. Use clone({bindings: {...}}) when an appearance needs separate texture resources. Adding a texture or changing a shader feature may require matching defines and a compatible model shader layout.

See the materials guide and pbrMaterial reference.

Usage

import {Model} from '@luma.gl/engine';
import {createPBRMaterial, type PBRMaterial} from '@luma.gl/experimental';

// device is an initialized Device.
const material: PBRMaterial = createPBRMaterial(device, {
  uniforms: {
    emissiveFactor: [0.1, 0.5, 0.9],
    emissiveStrength: 8
  }
});

// modelProps contains your shaders, geometry, and buffer layout.
const model = new Model(device, {
  ...modelProps,
  material
});

Emission is visible without a scene light, but does not illuminate nearby objects in this raster viewer. Bloom is a separate effect; tone mapping and display headroom affect the apparent difference between high strengths. See emissive surfaces for core emissive textures.

glTF support

KHR_materials_emissive_strength.emissiveStrength multiplies core emissiveFactor and emissiveTexture. When the extension is absent the multiplier is 1. The parser preserves this scalar in PBRMaterial; this field does not require USE_MATERIAL_EXTENSIONS in the current shader.

See glTF materials and textures and the extension support matrix for import details.

All engine features