title: PNG Premultiplied Alpha, iOS Simulator vs iPad
body: <p>I use <code>GLKTextureLoader</code> to load a 32bit PNG (created in GIMP). The <code>GLKTextureInfo</code> returned is showing <code>GLKTextureInfoAlphaStateNonPremultiplied</code> for the <code>alphaState</code> on both the simulator and iPad. Experimenting with <code>glBlendFunc</code> and GLKTextureLoader I can get it work on the iPad or simulator, but not both!</p>
  
  <p>With no options to GLKTextureLoader, and with the following blend func:</p>
  
  <pre><code>glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
  </code></pre>
  
  <p>I get on the iOS Simulator (notice the glow on the text is bright)</p>
  
  <p><img src="https://i.stack.imgur.com/JKQ0Y.png" alt="enter image description here"></p>
  
  <p>And on a 4th iPad (notice the glow on the text is dark)</p>
  
  <p><img src="https://i.stack.imgur.com/6CsLL.png" alt="enter image description here"></p>
  
  <p>Why the difference? The <code>alphaState</code> is the same. What could it be?</p>