Optimizing multiple continuous animations that are heating up device - ios

Question

I’m working on a project that has about 16 UIViews on a ViewController.
Some of the UIView contain some processor intensive CG drawings with transparency done at load time, while other UIView are animating. In particular, the following rotating animations run continuously. (If I look very closely, the animations appear not entirely smooth.)
The device I’m testing on is warming up, it’s not hot, but getting very warm. I’m concerned I’m overloading the processor.
Question:
Is there a more efficient way to complete the below animations which run continuously using a method that is less resource hungry and prevents the device from heating up?
Xcode instruments:
At load (max): CPU: 56% - Memory: 29MB
When running (max): CPU: 1% - Memory: 29MB
func rotateForward() {
UIView.animateWithDuration(2, delay: 0, options: .CurveLinear, animations: { () -> Void in
self.viewA.transform = CGAffineTransformRotate(self.viewA.transform, CGFloat(M_PI_2))
self.viewB.transform = CGAffineTransformRotate(self.viewB.transform, CGFloat(M_PI_2))
self.viewC.transform = CGAffineTransformRotate(self.viewC.transform, CGFloat(M_PI_2))
self.viewD.transform = CGAffineTransformRotate(self.viewD.transform, CGFloat(M_PI_2))
}) { (finished) -> Void in
self.rotateForward()
}
}
func rotateBack() {
UIView.animateWithDuration(2, delay: 0, options: .CurveLinear, animations: { () -> Void in
self.viewW.transform = CGAffineTransformRotate(self.viewW.transform, -CGFloat(M_PI_2))
self.viewX.transform = CGAffineTransformRotate(self.viewX.transform, -CGFloat(M_PI_2))
self.viewY.transform = CGAffineTransformRotate(self.viewY.transform, -CGFloat(M_PI_2))
self.viewZ.transform = CGAffineTransformRotate(self.viewZ.transform, -CGFloat(M_PI_2))
}) { (finished) -> Void in
self.rotateBack()
}
}

Answer 1

Instead of using CPU to run these animation , you can use GPU to perform them.
You can use this protocol to make the view rotate forward. Try to subclass the views to implement this protocol and try it out.
protocol Rotate{ }
extension Rotate where Self: UIView {
func rotate() {
let animation = CABasicAnimation(keyPath: "transform.rotation")
animation.duration = 2
animation.repeatCount = Float.infinity
animation.fromValue = 0.0
animation.toValue = Float(M_PI * 2.0)
layer.addAnimation(animation, forKey: "position")
}
}