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Scenegraph Lights

Scenegraph lighting attaches light definitions to spatial nodes. AreaLightController resolves visible rectangle and disk emitters using current node transforms; the shared lighting shaders implement their surface response. Punctual lights use the existing directional, point, and spot light descriptions.

Example​

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Construct an area light​

import {AreaLightController, GroupNode} from '@luma.gl/engine';

const lightNode = new GroupNode({position: [0, 3, 0]});
const scene = new GroupNode({children: [lightNode]});
const areaLights = new AreaLightController({
  scenes: [scene],
  bindings: [{
    node: lightNode,
    definition: {type: 'rect', width: 4, height: 2, intensity: 1000, color: [1, 1, 1]}
  }]
});

// model uses the compatible shared lighting/PBR shader modules.
model.shaderInputs.setProps({
  lighting: {lights: areaLights.getLights(), useByteColors: false}
});

getLights(sceneIndex) recomputes current world-space light instances after animation. Invisible branches do not emit. Definitions use normalized linear colors; intensity is luminance in nits. Emitters face local negative Z. Increasing area at fixed luminance increases emitted flux.

The controller borrows scene nodes. Explicit matrix-authored nodes require the matching matrixAuthored/matrixNodes metadata so orientation can be resolved independently of scale. The shader and renderer must support the returned area-light type; merely attaching a light definition does not add a lighting pass or configure its resources.

Rendering support​

The shared PBR path supports rectangle and disk emitters with bounded direct-light evaluation. LTC resources can accelerate supported lobes; a numerical fallback has a sample-count tradeoff. This path does not provide area-light shadows, indirect bounces, or universal integration across all material families. See lighting for shader inputs and glTF area-light conversion for importer profile limits.

See punctual lighting, Materials, and Scenegraphs.