fireball/lib/lights/PointLight.js

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2018-12-25 13:59:22 +00:00
import { Light } from './Light.js';
import { PerspectiveCamera } from '../cameras/PerspectiveCamera.js';
import { LightShadow } from './LightShadow.js';
/**
* @author mrdoob / http://mrdoob.com/
*/
function PointLight( color, intensity, distance, decay ) {
Light.call( this, color, intensity );
this.type = 'PointLight';
Object.defineProperty( this, 'power', {
get: function () {
// intensity = power per solid angle.
// ref: equation (15) from https://seblagarde.files.wordpress.com/2015/07/course_notes_moving_frostbite_to_pbr_v32.pdf
return this.intensity * 4 * Math.PI;
},
set: function ( power ) {
// intensity = power per solid angle.
// ref: equation (15) from https://seblagarde.files.wordpress.com/2015/07/course_notes_moving_frostbite_to_pbr_v32.pdf
this.intensity = power / ( 4 * Math.PI );
}
} );
this.distance = ( distance !== undefined ) ? distance : 0;
this.decay = ( decay !== undefined ) ? decay : 1; // for physically correct lights, should be 2.
this.shadow = new LightShadow( new PerspectiveCamera( 90, 1, 0.5, 500 ) );
}
PointLight.prototype = Object.assign( Object.create( Light.prototype ), {
constructor: PointLight,
isPointLight: true,
copy: function ( source ) {
Light.prototype.copy.call( this, source );
this.distance = source.distance;
this.decay = source.decay;
this.shadow = source.shadow.clone();
return this;
}
} );
export { PointLight };