anchor.diff:      body2.syncFromNode();
   
       var ballbody = new ArcadeBody()
  -      ..position = new Vector2(400.0, 300.0)
  -      ..speed = new Vector2(-100.0, 200.0)
  +      ..position = new Vector2(400.0, 200.0)
  +      ..speed = new Vector2(0.0, 0.0)
         ..restitution = new Vector2(1.0, 1.0)
         ..addTo(world);
   
  
positive.code:     wallsCollision.collider1 = ballbody.collider;
      wallsCollision.collider2 = world.collider;
      wallsCollision.onCollision.listen(bounce);
      world.collisions.add(wallsCollision);
  
      body1.collider = new AABB2Collider();
  
negative.code: main() {
    var game = new GameLoop('#gamebox', width: 800, height: 400);
    game.debug = new DebugDrawer('debuger');
    game.timeScale = 1.0;
  
    var loader = new AssetLoader();
    loader.add('paddle', new ImageAsset('paddle.png'));
    loader.add('ball', new ImageAsset('ball.png'));
  