title: I want to draw a rectangle like shape with drag-able corners in IOS
body: <p>I want to overlay a a box shape over a photograph and allow the user to select each corner, and drag the corners to where they want.</p>
  
  <p>I could use 4 invisible buttons(to represent each corner) that respond to drag events to get the x,y points for each corner, but is there some line drawing functionality available in xcode without touching any of the game api classes? I guess I want to draw lines onto a UIView.</p>
  
  <p>Many Thanks,
  -Code</p>