[SWIFT]UIImage Extension

import UIKit

extension UIImage {
	/// 이미지 사이즈 조정
    func resizeImage(size: CGSize) -> UIImage {
        let originalSize = self.size
        let ratio: CGFloat = {
            return originalSize.width > originalSize.height ? 1 / (size.width / originalSize.width) :
            1 / (size.height / originalSize.height)
        }()
        
        return UIImage(cgImage: self.cgImage!, scale: self.scale * ratio, orientation: self.imageOrientation)
    }
    
    /// 이미지 사이즈 배율에 맞게 resize
    /*
    사용방법 : let img =  image.resize(newWidth: 1024)
    */
    func resize(newWidth: CGFloat) -> UIImage {
        let scale = newWidth / self.size.width
        let newHeight = self.size.height * scale
        let size = CGSize(width: newWidth, height: newHeight)
        let render = UIGraphicsImageRenderer(size: size)
        let renderImage = render.image { context in
            self.draw(in: CGRect(origin: .zero, size: size))
        }
        
        print("화면 배율: \(UIScreen.main.scale)")
        // 배수
        print("origin: \(self), resize: \(renderImage)")
        
        return renderImage
    }
}