old_contents: driver = new game(document.getElementById("game"));
  
  driverCam = new camera();
  driverCam.ZoomInToFitWithOf = 700;
  driverCam.focusPosition = setting.BOTTOM;
  driverScene = new scene(driverCam)
  
  
  driverScene.pullLeft = function(){
  	player.move = new vector2D(-0.25, -0.5)
  	//player.position.add(new vector2D(-100, 0))
  }
  driverScene.pullRight = function(){
  	player.move = new vector2D(0.25, -0.5)
  	//player.position.add(new vector2D(100, 0))
  }
  
  driverScene.pullDown = function(){
  	player.move = new vector2D(0, -0.5)
  }
  
  driverScene.pullUp = function(){
  	player.move = new vector2D(0, -0.5)
  }
  
  
  
  driver.addScene(driverScene);
  
  IceImage = new Image();
  IceImage.src = "./ice.png";
  
  RoadImage = new Image();
  RoadImage.src = "./road.png"
  
  road = new gBackground();
  road.size = new vector2D(600, 100);
  road.color = "blue";
  road.image = RoadImage;
  road.fixHeight = false;
  road.position = new vector2D(-300, -800);
  driverScene.addGPObject(road);
  
  IceBlock = new Array();
  
  for(i = 0; i <= 100; i++){
  	IceBlock[i] = new gpObject();
  	IceBlock[i].size = new vector2D(100, 100);
  	IceBlock[i].color = "blue";
  	IceBlock[i].name = "Ice"
  	IceBlock[i].image = IceImage;
  	IceBlock[i].fixHeight = false;
  	x = Math.round(Math.random()*600-300);
  	y = Math.round(Math.random()*300) - 800;
  	IceBlock[i].position = new vector2D(x , -i*800 + y);
  	driverScene.addGPObject(IceBlock[i]);
  }
  
  
  player = new gpObject();
  player.size = new vector2D(100, 100);
  player.onCollide = function(ele){
  	if(ele.name == "Ice"){
  		alert("gameover: " + ele.name);
  	}
  }
  player.position = new vector2D(-50, 0);
  PlayerImage = new Image();
  PlayerImage.src = "./player.png"
  player.image= PlayerImage;
  player.fixHeight = false;
  player.move = new vector2D(0, -0.5)
  driverScene.addGPObject(player);
  driverCam.focusTo = player;
  
  cameraFocus = new gpObject();
  cameraFocus.size = new vector2D(100, 200);
  cameraFocus.color = "rgba(0, 0, 0, 0)"
  cameraFocus.position = new vector2D(-50, 100);
  cameraFocus.fixHeight = false;
  cameraFocus.move = new vector2D(0, -0.5)
  driverScene.addGPObject(cameraFocus);
  driverCam.focusTo = cameraFocus;
  
  
  
  Interval = setInterval(function(){driver.update();}, Math.floor(1000/30));
new_contents: driver = new game(document.getElementById("game"));
  
  driverCam = new camera();
  driverCam.ZoomInToFitWithOf = 700;
  driverCam.focusPosition = setting.BOTTOM;
  driverScene = new scene(driverCam)
  
  
  driverScene.pullLeft = function(){
  	player.move = new vector2D(-0.25, -0.5)
  	//player.position.add(new vector2D(-100, 0))
  }
  driverScene.pullRight = function(){
  	player.move = new vector2D(0.25, -0.5)
  	//player.position.add(new vector2D(100, 0))
  }
  
  driverScene.pullDown = function(){
  	player.move = new vector2D(0, -0.5)
  }
  
  driverScene.pullUp = function(){
  	player.move = new vector2D(0, -0.5)
  }
  
  
  
  driver.addScene(driverScene);
  
  IceImage = new Image();
  IceImage.src = "./ice.png";
  
  RoadImage = new Image();
  RoadImage.src = "./road.png"
  
  road = new gBackground();
  road.size = new vector2D(600, 100);
  road.color = "blue";
  road.image = RoadImage;
  road.fixHeight = false;
  road.position = new vector2D(-300, -800);
  driverScene.addGPObject(road);
  
  IceBlock = new Array();
  
  for(i = 0; i <= 100; i++){
  	IceBlock[i] = new gpObject();
  	IceBlock[i].size = new vector2D(100, 100);
  	IceBlock[i].color = "blue";
  	IceBlock[i].name = "Ice"
  	IceBlock[i].image = IceImage;
  	IceBlock[i].fixHeight = false;
  	x = Math.round(Math.random()*600-300);
  	y = Math.round(Math.random()*300) - 800;
  	IceBlock[i].position = new vector2D(x , -i*800 + y);
  	driverScene.addGPObject(IceBlock[i]);
  }
  
  
  player = new gpObject();
  player.size = new vector2D(100, 100);
  player.onCollide = function(ele){
  	if(ele.name == "Ice"){
  		alert("gameover: " + ele.name);
  	}
  }
  player.position = new vector2D(-50, 0);
  PlayerImage = new Image();
  PlayerImage.src = "./player.png"
  player.image= PlayerImage;
  player.fixHeight = false;
  player.move = new vector2D(0, -0.5)
  driverScene.addGPObject(player);
  driverCam.focusTo = player;
  
  cameraFocus = new gpObject();
  cameraFocus.size = new vector2D(100, 200);
  cameraFocus.color = "rgba(0, 0, 0, 0)"
  cameraFocus.position = new vector2D(-50, 0);
  cameraFocus.fixHeight = false;
  cameraFocus.move = new vector2D(0, -0.5)
  driverScene.addGPObject(cameraFocus);
  driverCam.focusTo = cameraFocus;
  
  
  
  Interval = setInterval(function(){driver.update();}, Math.floor(1000/30));
subject: fix camera position