title: iOS: Non-square hit areas for buttons
body: <p>I need to make some triangular buttons that overlap each other.</p>
  
  <p>While UIButtons can take transparent images as backgrounds, and UIControls can have custom views, the hit area of these is always square. How can I create a triangular hitarea for my buttons?</p>
  
  <p>I come from a FLash background so I would normally create a hitarea for my view, but I don't believe I can do this in Cocoa.</p>
  
  <p>Any tips?</p>