Chapter 148: SpotLightNode

Core Idea

Module for representing spot lights as nodes.

Key Concepts

• colorNode : UniformNode.<Color>: Uniform node representing the light color.
• coneCosNode : UniformNode.<float>: Uniform node representing the cone cosine.
• cutoffDistanceNode : UniformNode.<float>: Uniform node representing the cutoff distance.
• decayExponentNode : UniformNode.<float>: Uniform node representing the decay exponent.
• penumbraCosNode : UniformNode.<float>: Uniform node representing the penumbra cosine.

Reference Tables

Constructor

Signature
new SpotLightNode( light : SpotLight )

Properties

Property	Description
.colorNode : UniformNode.<Color>	Uniform node representing the light color.
.coneCosNode : UniformNode.<float>	Uniform node representing the cone cosine.
.cutoffDistanceNode : UniformNode.<float>	Uniform node representing the cutoff distance.
.decayExponentNode : UniformNode.<float>	Uniform node representing the decay exponent.
.penumbraCosNode : UniformNode.<float>	Uniform node representing the penumbra cosine.

Methods

Method	Description
.getSpotAttenuation( builder : NodeBuilder, angleCosine : Node.<float> ) : Node.<float>	Computes the spot attenuation for the given angle.
.update( frame : NodeFrame )	Overwritten to updated spot light specific uniforms.

Key Takeaways

1. SpotLightNode extends: EventDispatcher → Node → LightingNode → AnalyticLightNode
2. Most relevant properties: colorNode, coneCosNode, cutoffDistanceNode, decayExponentNode.
3. Key methods: getSpotAttenuation, update.

Connects To

• EventDispatcher: parent class
• Node: parent class
• LightingNode: parent class
• AnalyticLightNode: parent class
• Source: src/nodes/lighting/SpotLightNode.js