var timeAnimation = 2;
var coinsLabel:SKLabelNode = SKLabelNode(text: "0");
var gainCoin = 400;
var currentCoin = 20;

func addCoin(coinTotal:Int)
{
    currentCoin = coinTotal+currentCoin;

    self.runAction(SKAction.customActionWithDuration(timeAnimation, updateLabel));

    func updateLabel(node:SKNode!, t:CGFloat) -> Void{
        let coinToAdd = currentCoin*(t/timeAnimation);
        coinsLabel.text = ""+Int(coinToAdd);
    }
}

override func update(currentTime: NSTimeInterval)
{
   if i <= score
   {
     scoreText.text = "Score (i)"
     i++
   }
}