old_contents: function SpriteManager() {
  
  	var sprites = new Array();
  
  	/**
  	 * add sprite to collection
  	 *
  	 * @return void
  	 */
  	this.addSprite = function(sprite) {
  		sprite.setManager(this);
  		sprites.push(sprite);
  	};
  
  	/**
  	 * set player sprite that reacts on the mouse
  	 *
  	 * @return void
  	 */
  	this.setPlayer = function(next_player) {
  
  		$.each(sprites, function(k, v) {
  			v.setPlayer(false);
  		});
  		sprites[next_player].setPlayer(true);
  	}
  
  	/**
  	 * print out manager status
  	 *
  	 * @return void
  	 */
  	this.status = function() {
  		var status = {sprites: {}};
  		$.each(sprites, function(k, sprite) {
  			status.sprites[k] = {isPlayer: sprite.isPlayer(), object: sprite};
  		});
  		console.log(status);
  	}
  
  	/**
  	 * update loop
  	 *
  	 * @return void
  	 */
  	this.updateSprites = function() {
  		var self = this;
  		window.setTimeout(function() {
  			$.each(sprites, function(k, sprite) {
  				sprite.update();
  			});
  			self.updateSprites();
  		}, 1000 / 25);
  	}
  
  }
  
new_contents: function SpriteManager() {
  
  	var sprites = new Array();
  
  	/**
  	 * add sprite to collection
  	 *
  	 * @return void
  	 */
  	this.addSprite = function(sprite) {
  		sprite.setManager(this);
  		sprites.push(sprite);
  	};
  
  	/**
  	 * set player sprite that reacts on the mouse
  	 *
  	 * @param {Sprite} next_player
  	 * @return void
  	 */
  	this.setPlayer = function(next_player) {
  		$.each(sprites, function(k, v) {
  			v.setPlayer(false);
  
  			if (v == next_player) {
  				next_player = k;
  			}
  		});
  
  		sprites[next_player].setPlayer(true);
  	}
  
  	/**
  	 * print out manager status
  	 *
  	 * @return void
  	 */
  	this.status = function() {
  		var status = {sprites: {}};
  		$.each(sprites, function(k, sprite) {
  			status.sprites[k] = {isPlayer: sprite.isPlayer(), object: sprite};
  		});
  		console.log(status);
  	}
  
  	/**
  	 * update loop
  	 *
  	 * @return void
  	 */
  	this.updateSprites = function() {
  		var self = this;
  		window.setTimeout(function() {
  			$.each(sprites, function(k, sprite) {
  				sprite.update();
  			});
  			self.updateSprites();
  		}, 1000 / 25);
  	}
  
  }
  
subject: change set player to accept an object