title: Get all widgets under cursor
body: <p>The <code>widgetAt</code> function gives me the widget directly under the cursor, at the highest z-order.</p>
  
  <pre><code>pos = QtGui.QCursor.pos()
  widget = QtGui.qApp.widgetAt(pos)
  </code></pre>
  
  <p>But how can I get <em>all</em> widgets under the cursor? Including those behind the top-most one? Something like:</p>
  
  <pre><code>pos = QtGui.QCursor.pos()
  widgets = QtGui.qApp.widgetsAt(pos)
  </code></pre>
  
  <h3>Example</h3>
  
  <p>As an example of use, picture an overlay which adds animated graphics, like ripples on the surface of water, wherever the user clicked. Naturally, the overlay would need to receive and respond to clicks, but it must do so without interfering with clicks propagating to widgets underneath it.</p>
  
  <p>Another example is usage tracking; to intercept and record clicks for analysis, the same overlay can be used but this time nothing is drawn, only collected.</p>
  
  <p>In both cases, if only one widget is getting the click event, I'll need a way of distinguishing what widgets reside underneath it so as to pass the event on.</p>