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';
}
/**
* Overwrites the default implementation to compute an IES conform spot attenuation.
*
* @param {Node<float>} angleCosine - The angle to compute the spot attenuation for.
* @return {Node<float>} The spot attenuation.
*/
getSpotAttenuation( angleCosine ) {
const iesMap = this.light.iesMap;
let spotAttenuation = null;
if ( iesMap && iesMap.isTexture === true ) {
const angle = angleCosine.acos().mul( 1.0 / Math.PI );
spotAttenuation = texture( iesMap, vec2( angle, 0 ), 0 ).r;
} else {
spotAttenuation = super.getSpotAttenuation( angleCosine );
}
return spotAttenuation;
}
}
export default IESSpotLightNode;