UIImage+Overlay.swift

import UIKit


public extension UIImage {
    
    public func imageWithColor(color: UIColor) -> UIImage {
        UIGraphicsBeginImageContextWithOptions(self.size, false, self.scale)
        let context: CGContextRef = UIGraphicsGetCurrentContext()
        CGContextTranslateCTM(context, 0, self.size.height)
        CGContextScaleCTM(context, 1.0, -1.0)
        
        CGContextSetBlendMode(context, CGBlendMode.Normal)
        let rect: CGRect = CGRectMake(0, 0, self.size.width, self.size.height)
        CGContextClipToMask(context, rect, self.CGImage)
        color.setFill()
        CGContextFillRect(context, rect)
        let newImage: UIImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return newImage
    }
    
}