title: How can I modify pixels using SDL?
body: <p>I have a slight problem: I can't modify the pixels of an SDL screen. </p>
  
  <p>Specifically, the following code doesn't work.</p>
  
  <pre><code>Uint32 * pixels = (Uint32 *) screen -&gt; pixels; 
  screen -&gt; pixels = pixels;
  </code></pre>
  
  <p>This compiles, but it doesn't show anything. What am I missing?</p>