UIImage tint with UIColor in Swift

UIImageTintCGExtension.swift

extension UIImage
{
    func tint(color: UIColor, blendMode: CGBlendMode) -> UIImage
    {
        let drawRect = CGRectMake(0.0, 0.0, size.width, size.height)
        UIGraphicsBeginImageContextWithOptions(size, false, scale)
        let context = UIGraphicsGetCurrentContext()
        CGContextClipToMask(context, drawRect, CGImage)
        color.setFill()
        UIRectFill(drawRect)
        drawInRect(drawRect, blendMode: blendMode, alpha: 1.0)
        let tintedImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return tintedImage
    }
}

UIImageTintCIFunction.swift

func tint(image: UIImage, color: UIColor) -> UIImage
{
    let ciImage = CIImage(image: image)
    let filter = CIFilter(name: "CIMultiplyCompositing")

    let colorFilter = CIFilter(name: "CIConstantColorGenerator")
    let ciColor = CIColor(color: color)
    colorFilter.setValue(ciColor, forKey: kCIInputColorKey)
    let colorImage = colorFilter.outputImage

    filter.setValue(colorImage, forKey: kCIInputImageKey)
    filter.setValue(ciImage, forKey: kCIInputBackgroundImageKey)

    return UIImage(CIImage: filter.outputImage)!
}

Hi Alex, great code. I have used the extension you wrote but I had to add this two lines after the context`s creation
// flip the image
CGContextScaleCTM(context, 1.0, -1.0)
CGContextTranslateCTM(context, 0.0, -self.size.height)
Because the final image appears flipped. Maybe it is useful for you.

Thanks!

Here is a gist with an alternative implementation: https://gist.github.com/fabb/007d30ba0759de9be8a3