three
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JavaScript 3D library
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JavaScript
import SpotLightNode from './SpotLightNode.js';
import { texture } from '../accessors/TextureNode.js';
import { vec2 } from '../tsl/TSLBase.js';
/**
* An IES version of the default spot light node.
*
* @augments SpotLightNode
*/
class IESSpotLightNode extends SpotLightNode {
static get type() {
return 'IESSpotLightNode';
}
/**
* Constructs a new IES spot light node.
*
* @param {?SpotLight} [light=null] - The spot light source.
*/
constructor( light = null ) {
super( light );
/**
* The texture node representing the IES texture.
*
* @type {?TextureNode}
* @default null
*/
this._iesTextureNode = null;
}
/**
* Overwrites the default implementation to compute an IES conform spot attenuation.
*
* @param {NodeBuilder} builder - The node builder.
* @param {Node<float>} angleCosine - The angle to compute the spot attenuation for.
* @return {Node<float>} The spot attenuation.
*/
getSpotAttenuation( builder, angleCosine ) {
const iesMap = this.light.iesMap;
let spotAttenuation = null;
if ( iesMap && iesMap.isTexture === true ) {
const angle = angleCosine.acos().mul( 1.0 / Math.PI );
this._iesTextureNode = texture( iesMap, vec2( angle, 0 ), 0 );
spotAttenuation = this._iesTextureNode.r;
} else {
spotAttenuation = super.getSpotAttenuation( builder, angleCosine );
}
return spotAttenuation;
}
/**
* Overwritten to update the IES spot light texture.
*
* @param {NodeFrame} frame - A reference to the current node frame.
*/
update( frame ) {
super.update( frame );
if ( this._iesTextureNode !== null && this.light.iesMap ) {
this._iesTextureNode.value = this.light.iesMap;
}
}
}
export default IESSpotLightNode;