With the code below, I am successfully masking part of my drawing, but it\'s the inverse of what I want masked. This masks the inner portion of the drawing, where I would li
For Swift 4.2
func mask(viewToMask: UIView, maskRect: CGRect, invert: Bool = false) {
let maskLayer = CAShapeLayer()
let path = CGMutablePath()
if (invert) {
path.addRect(viewToMask.bounds)
}
path.addRect(maskRect)
maskLayer.path = path
if (invert) {
maskLayer.fillRule = .evenOdd
}
// Set the mask of the view.
viewToMask.layer.mask = maskLayer;
}