How to get the pixel color on touch?

Question

I know this is a common question and there are a lot of answers of this question. I\'ve used some of this. Although many of them are the same. But the sad thing for me is th

Answer 1

Thank you for @Aggressor's post the code above

Swift 2.1

func getPixelColorAtPoint(point:CGPoint) -> UIColor{

   let pixel = UnsafeMutablePointer.alloc(4)
   let colorSpace = CGColorSpaceCreateDeviceRGB()
   let bitmapInfo = CGBitmapInfo(rawValue: CGImageAlphaInfo.PremultipliedLast.rawValue)
   let context = CGBitmapContextCreate(pixel, 1, 1, 8, 4, colorSpace, bitmapInfo.rawValue)

   CGContextTranslateCTM(context, -point.x, -point.y)
   view.layer.renderInContext(context!)
   let color:UIColor = UIColor(red: CGFloat(pixel[0])/255.0, green: CGFloat(pixel[1])/255.0, blue: CGFloat(pixel[2])/255.0, alpha: CGFloat(pixel[3])/255.0)

   pixel.dealloc(4)
   return color
}

Swift 3, Xcode Version 8.2 (8C38) and Swift 4, Xcode Version 9.1 (9B55)

 func getPixelColorAtPoint(point:CGPoint, sourceView: UIView) -> UIColor{

    let pixel = UnsafeMutablePointer.allocate(capacity: 4)
    let colorSpace = CGColorSpaceCreateDeviceRGB()
    let bitmapInfo = CGBitmapInfo(rawValue: CGImageAlphaInfo.premultipliedLast.rawValue)
    let context = CGContext(data: pixel, width: 1, height: 1, bitsPerComponent: 8, bytesPerRow: 4, space: colorSpace, bitmapInfo: bitmapInfo.rawValue)
    var color: UIColor? = nil

    if let context = context {
        context.translateBy(x: -point.x, y: -point.y)
        sourceView.layer.render(in: context)

        color = UIColor(red: CGFloat(pixel[0])/255.0,
                        green: CGFloat(pixel[1])/255.0,
                        blue: CGFloat(pixel[2])/255.0,
                        alpha: CGFloat(pixel[3])/255.0)

        pixel.deallocate(capacity: 4)
    }
    return color
}