Before we can animate our z axis, we need to add perspective to our user interface.
Replace the buildCircleLayers method with the following code:
func buildCircleLayers() { for i in 0..<colors.count { let layer = CALayer() layer.bounds = CGRect(x: 0.0, y: 0.0, width: 40.0, height: 40.0) layer.position = CGPoint(x: 130, y: 40) layer.zPosition = CGFloat(-3 * i) layer.borderColor = colors[i] layer.borderWidth = 2.0 layer.cornerRadius = layer.bounds.width * 0.5 circleLayers.append(layer) cosmicDoor.addSublayer(layer) } var perspective = CATransform3DIdentity perspective.m34 = -0.2 cosmicDoor.sublayerTransform = perspective}
We iterate through the colors array, as we have done before, and as you can see, ...
