title: UIImageView content mode and scale factor
body: <p>I have a programmatically created UIImage image, using this kind of code:</p>
  
  <pre><code>UIGraphicsBeginImageContextWithOptions(CGSizeMake(128, 128), NO, 0.0f);
  // Render in context
  UIImage *resultImage = UIGraphicsGetImageFromCurrentImageContext();
  UIGraphicsEndImageContext();
  </code></pre>
  
  <p>Since my context options specify scale of 0, on retina devices it will be set to 2, and I can confirm that on resulting UIImage scale property. </p>
  
  <p>Now, the problem is that this image size is 128x128, scale 2. When I am putting it into UIImageView of size 64x64 and contentMode = Center, it renders my image outside imageview, presumably rendering into 128x128 box without any scaling.</p>
  
  <p>My understanding of retina graphics was that if an image has scale factor 2.0, the it should be rendered at 1/2 size, thus resulting in higher DPI. 
  So I was expecting the image view to render 64x64 image at retina quality. Where am I wrong?</p>