title: CATiledLayer & retina display
body: <p>Does anyone have any tricks for improving the performance of CATiledLayer on a retina display?</p>
  
  <p>This post:
  <a href="https://stackoverflow.com/questions/9691891/catiledlayer-in-ipad-retina-simulator-yields-poor-performance">CATiledLayer in iPad retina simulator yields poor performance</a></p>
  
  <p>implies that there are issues with the simulator, but I'm noticing poor performance on the actual <em>device</em> as well.  It's a pretty obvious issue since it's loading larger tiles sooner on the retina display.  The only thing I can thing of is to reprocess the tiled images with more levels of detail.</p>
  
  <p>I do one little trick:</p>
  
  <pre><code>    CGFloat scale = CGContextGetCTM(context).a / self.contentScaleFactor;
  </code></pre>
  
  <p>when calculating the scale, but that doesn't seem to be enough to deal with the poor performance.</p>