text: var Vector3 = require('../../math/Vector3');
  var Light = require('../../renderer/light/Light');
  
  /**
   * A directional light
   * @example-link http://code.gooengine.com/latest/visual-test/goo/renderer/light/Lights-vtest.html Working example
   * @extends Light
   * @param {Vector3} [color=(1, 1, 1)] The color of the light
   */
  function DirectionalLight(color) {
  	Light.call(this, color);
  
  	/**
  	 * The direction vector of the light
  	 * @readonly
  	 * @type {Vector3}
  	 */
  	this.direction = new Vector3();
  
  	// @ifdef DEBUG
  	Object.seal(this);
  	// @endif
  }
  
  DirectionalLight.prototype = Object.create(Light.prototype);
  DirectionalLight.prototype.constructor = DirectionalLight;
  
  /**
   * Updates the light's translation and orientation
   * @hidden
   * @param {Transform} transform
   */
  DirectionalLight.prototype.update = function (transform) {
  	transform.matrix.getTranslation(this.translation);
  	this.direction.setDirect(0.0, 0.0, -1.0);
  	this.direction.applyPostVector(transform.matrix);
  };
  
  DirectionalLight.prototype.copy = function (source) {
  	Light.prototype.copy.call(this, source);
  
  	this.direction.copy(source.direction);
  
  	return this;
  };
  
  DirectionalLight.prototype.clone = function () {
  	var clone = new DirectionalLight(this.color.clone());
  	clone.copy(this);
  	return clone;
  };
  
  module.exports = DirectionalLight;