constructor( light, size, color ) {

		super();

		/**
		 * The light being visualized.
		 *
		 * @type {DirectionalLight}
		 */
		this.light = light;

		this.matrix = light.matrixWorld;
		this.matrixAutoUpdate = false;

		/**
		 * The color parameter passed in the constructor.
		 * If not set, the helper will take the color of the light.
		 *
		 * @type {number|Color|string}
		 */
		this.color = color;

		this.type = 'DirectionalLightHelper';

		if ( size === undefined ) size = 1;

		let geometry = new BufferGeometry();
		geometry.setAttribute( 'position', new Float32BufferAttribute( [
			- size, size, 0,
			size, size, 0,
			size, - size, 0,
			- size, - size, 0,
			- size, size, 0
		], 3 ) );

		const material = new LineBasicMaterial( { fog: false, toneMapped: false } );

		/**
		 * Contains the line showing the location of the directional light.
		 *
		 * @type {Line}
		 */
		this.lightPlane = new Line( geometry, material );
		this.add( this.lightPlane );

		geometry = new BufferGeometry();
		geometry.setAttribute( 'position', new Float32BufferAttribute( [ 0, 0, 0, 0, 0, 1 ], 3 ) );

		/**
		 * Represents the target line of the directional light.
		 *
		 * @type {Line}
		 */
		this.targetLine = new Line( geometry, material );
		this.add( this.targetLine );

		this.update();

	}
Constructs a new directional light helper.

@param {DirectionalLight} light - The light to be visualized.
@param {number} [size=1] - The dimensions of the plane.
@param {number|Color|string} [color] - The helper's color. If not set, the helper will take
the color of the light.