function SpotLightHelper( light ) {

		Object3D.call( this );

		this.light = light;
		this.light.updateMatrixWorld();

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

		var geometry = new BufferGeometry();

		var positions = [
			0, 0, 0,   0,   0,   1,
			0, 0, 0,   1,   0,   1,
			0, 0, 0, - 1,   0,   1,
			0, 0, 0,   0,   1,   1,
			0, 0, 0,   0, - 1,   1
		];

		for ( var i = 0, j = 1, l = 32; i < l; i ++, j ++ ) {

			var p1 = ( i / l ) * Math.PI * 2;
			var p2 = ( j / l ) * Math.PI * 2;

			positions.push(
				Math.cos( p1 ), Math.sin( p1 ), 1,
				Math.cos( p2 ), Math.sin( p2 ), 1
			);

		}

		geometry.addAttribute( 'position', new Float32BufferAttribute( positions, 3 ) );

		var material = new LineBasicMaterial( { fog: false } );

		this.cone = new LineSegments( geometry, material );
		this.add( this.cone );

		this.update();

	}
@author alteredq / http://alteredqualia.com/
@author mrdoob / http://mrdoob.com/
@author WestLangley / http://github.com/WestLangley