func maskImage(image:UIImage, mask:(UIImage))->UIImage{
let imageReference = image.CGImage
let maskReference = mask.CGImage
let imageMask = CGImageMaskCreate(CGImageGetWidth(maskReference),
CGImageGetHeight(maskReference),
CGImageGetBitsPerComponent(maskReference),
CGImageGetBitsPerPixel(maskReference),
CGImageGetBytesPerRow(maskReference),
CGImageGetDataProvider(maskReference), nil, true)
let maskedReference = CGImageCreateWithMask(imageReference, imageMask)
let maskedImage = UIImage(CGImage:maskedReference!)
return maskedImage}
использование
let image = UIImage(named: "image2.png")
let maskingImage = UIImage(named: "mask6.png")
imageView.image = maskImage(image!, mask: maskingImage!)