title: Google Maps shapes - How to prevent overlapping
body: <p>I'm trying to implement a map that let users draw some shapes (circles, rectangles and polygons) over it and that part is working right now.</p>
  
  <p>The problem is that users can draw a shape over another (overlapping) and the system shouldn't allow that. The same geographic area should not be covered by multiple shapes... when a user tries to do that they should be notified with a warning/info message.</p>
  
  <p>I've searched a lot and I've not found a working example anywhere or a clue of how to do that.</p>
  
  <p>Can you guys give any help - is it even possible to do?</p>
  
  <p>Thanks!</p>