title: save image from GLPaint Drawing into iPad ratina
body: <p>I am trying to save drawing as an image from <code>GLPaint</code> app from Apple sample code.<br>
  Saving the image is working fine in iPad(non-retina), but it issued when it runs on iPad(retina).<br>
  Whenever I run my app on iPad retina, then the image size is 1/4 from original.<br>
  Can anyone help me out from this?</p>