 class ViewController: UIViewController {
 
     let DEFAULT_BACKGROUND_IMAGE = "2801-11"
+    let REFERENCE_ANIMATION_DURATION = 40
+    let REFERENCE_ANIMATION_FAST_RETURN_DURATION = 3
+    let REFERENCE_MAX_TRAILING_CONTRAINT_CONSTANT = -400
+    
     
     enum direction
     {

    func stopanimation(notification :NSNotification)
    {
        FlagPauseAnimation = true
        
        lastPosToReach =  self.backImageTrailingConstraint.constant

        PauseLayer(self.view.layer)
    }
    

        
    }
    
    //MARK: White StatusBar : just for a better look
    override func preferredStatusBarStyle() -> UIStatusBarStyle {
        return .LightContent
    }
