var Player = function(game, gameSize){
   this.game = game;
   this.size = {width:16, height:16};
   this.position = {x: gameSize.x/2-this.size.width/2, y: gameSize.y/2-this.size.height/2};
   this.keyboarder = new Keyboarder();
  }
   
  Player.prototype = {
   update:function(){
    if(this.keyboarder.isDown(this.keyboarder.KEYS.LEFT)) {
     this.position.x -=2;
    }
   }
  }
   
  var Keyboarder = function(){
   var keyState = {};
    
   window.onkeydown = function(e){
    keyState[e.keyCode] = true;
   }
   window.onkeyup = function(e){
    keyState[e.keyCode] = false;
   }
    
   this.isDown = function(keyCode){
    return keyState[keyCode] === true;
   }
    
   this.KEYS = {LEFT: 37, RIGHT: 39, SPACE: 32};
  }