title: Easier way to find (visual) position of QModelIndex in QTreeView
body: <p>I'm interested in calculating the physical position of a node in <code>QTreeView</code> and can't find a way to do this (other than calculating it myself, which is cumbersome and error prone given the robustness of <code>QTreeView</code>).</p>
  
  <p>Is there a standard way of finding the draw position of data associated with a <code>QModelIndex</code> (something similar to the way <code>indexAt()</code> maps a position to a <code>QModelIndex</code>)?</p>