title: Matplotlib text bounding box dimensions
body: <h2>What I want to do:</h2>
  
  <p>I want to get the position and dimensions of a text instance in matplotlib world units (not screen pixels), with the intention of calculating and preventing text overlaps.</p>
  
  <p>I'm developing on Mac OSX 10.9.3, Python 2.7.5, matplotlib 1.3.1.</p>
  
  <h2>What I've tried:</h2>
  
  <p>Let <em>t</em> be a text instance.</p>
  
  <ol>
  <li><p><a href="https://stackoverflow.com/questions/22667224/matplotlib-get-text-bounding-box-independent-of-backend"><em>t</em>.get_window_extent(renderer)</a>: </p>
  
  <p>This gets bounding box dimensions in pixels, and I need world coordinates (normalized between -1.0 and 1.0 in my case).</p></li>
  <li><p><em>t</em>._get_bbox_patch(): </p>
  
  <pre><code>t = ax.text(x, y, text_string, prop_dict, bbox=dict(facecolor='red', alpha=0.5, boxstyle='square'))
  print t._get_bbox_patch()
  </code></pre>
  
  <p>When I execute the above sequence, the output is <code>FancyBboxPatchFancyBboxPatch(0,0;1x1)</code>. In the image I produce, the text instance is rendered properly with a red bounding box, so that output leads me to think that the FancyBbox is instantiated but not actually populated with real dimensions until render time.</p></li>
  </ol>
  
  <p>So, how can I get the position and dimensions of the text instance's bounding box in the same coord system units that I used for the <em>x</em> and <em>y</em> parameters I passed to <code>ax.text(...)</code>?</p>