     }
     
     override func animationDidStart(anim: CAAnimation) {
+        self.layer.shouldRasterize = true
         self.alpha = 1
     }
     

            self.alpha = 0
        }
        self.layer.removeAllAnimations()
        self.rotatedX(CGFloat(0))
    }
}

                constraint.firstItem.layer.transform = constraint.firstItem.transform3d()
            }
        }
        
        // added back view
        var previusView: RotatedView?
