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swiftuiimageuicolor

Change UIImage color without using Uiimageview in swift3


I want draw image pattern like star, one can change the color for that. Can I change the color of Image itself without using image view? I saw many answer changing tint color of UIImageview, but the effect is not applied to UIImage


Solution

  • Thank you all for the answers, but I got the solution working.

    func changePatternImageColor() {
        patternImage = UIImage(named: "pattern_star.png")!  //make sure to reinitialize the original image here every time you change the color
        UIGraphicsBeginImageContext(patternImage.size)
        let context = UIGraphicsGetCurrentContext()
        let color = UIColor(red: self.red, green: self.green, blue: self.blue, alpha: self.opacity)
        color.setFill()
        context?.translateBy(x: 0, y: patternImage.size.height)
        context?.scaleBy(x: 1.0, y: -1.0)
        //set the blend mode to color burn, and the original image
        context?.setBlendMode(CGBlendMode.exclusion)  //this does the magic.
        let rect = CGRect(x: 0, y: 0, width: patternImage.size.height, height: patternImage.size.height)
        context?.draw(patternImage.cgImage!, in: rect)
        //set the mask that matches the shape of the image, then draw color burn a colored rectangle
        context?.clip(to: rect, mask: patternImage.cgImage!)
        context?.addRect(rect)
        context?.drawPath(using: CGPathDrawingMode.fill)
        patternImage = UIGraphicsGetImageFromCurrentImageContext()!
        image_ref = patternImage.cgImage
        UIGraphicsEndImageContext()
    }
    

    The patternImage is the the image added in asset. P.S. the patternImage added in asset SHOULD be in black color