How Can I Rotate A UIImage and Image Data By 90 Degrees

Question

I have a UIImageView that contains an image. At the minute the user can click to save the image within the UIImageView to disk.

I would like to make it so that the the

Answer 1

The highlighted state of a UIButton did not take the correct orientation of the normal inserted turned image. So I had to redraw the image like @RyanG showed. Here is the Swift 2.2 code for that:

extension UIImage
{
    /// Rotate an image by any given radians.
    /// Works for 2x and 3x retina as well.
    func imageRotatedByDegrees(degrees: Double) -> UIImage
    {
        let radians = CGFloat(degrees * (M_PI / 180.0))

        let rotatedViewBox = UIView(frame: CGRect(origin: CGPointZero, size: self.size))
        let t: CGAffineTransform = CGAffineTransformMakeRotation(radians)
        rotatedViewBox.transform = t
        let rotatedSize = rotatedViewBox.frame.size

        UIGraphicsBeginImageContextWithOptions(rotatedSize, false, self.scale)
        let bitmap = UIGraphicsGetCurrentContext()

        CGContextTranslateCTM(bitmap, rotatedSize.width / 2, rotatedSize.height / 2)
        CGContextRotateCTM(bitmap, radians)
        CGContextScaleCTM(bitmap, 1.0, -1.0)
        CGContextDrawImage(bitmap, CGRect(origin: CGPoint(x: -self.size.width / 2, y: -self.size.height / 2), size: self.size), self.CGImage)

        let newImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return newImage
    }
}