Saving imageRef from GLPaint creates completely black image

Question

Hi I am trying out drawing app and have a problem when it comes to saving the image that is drawn. Right now I\'m very early in learning this but I have added code from: How

Answer 1

I found that changing the CGBitmapInfo into:

CGBitmapInfo bitmapInfo = kCGImageAlphaPremultipliedLast;

Results in a transparent background.