uiimage-extension-draw-image.swift

extension UIImage {
    
    public convenience init?(color: UIColor, size: CGSize = CGSize(width: 1, height: 1)) {
        let rect = CGRect(origin: .zero, size: size)
        UIGraphicsBeginImageContextWithOptions(rect.size, false, 0.0)
        color.setFill()
        UIRectFill(rect)
        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
guard let cgImage = image?.cgImage else { return nil }
        self.init(cgImage: cgImage)
    }
func image(byDrawingImage image: UIImage, inRect rect: CGRect) -> UIImage! {
        UIGraphicsBeginImageContext(size)
draw(in: CGRect(x: 0, y: 0, width: size.width, height: size.height))
        image.draw(in: rect)
        let result = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return result
    }
}
extension CGRect {
    var center: CGPoint { return CGPoint(x: midX, y: midY) }
}