title: How can I pass argument with requestAnimationFrame?
body: <p>In the main program I randomly choose an object which I'd like to animate, so I call the function with the object as the argument. The first loop is okay, <code>x</code> is finely set, but in the next turn it becomes <code>undefined</code>.</p>
  
  <p>Something like this:</p>
  
  <pre><code>var anim = {
          mainFunc: function(x) {
              anim.update(x);
              anim.redraw(x);
              window.requestAnimationFrame(anim.mainFunc);
          },
  
          update: function(x) {
  
          },
  
          redraw: function(x) {
  
          }
  };
  
  var n=Math.floor(Math.random() * (ArrayOfAnimObject.length));
  anim.mainFunc(ArrayOfAnimObject[n]);
  </code></pre>