title: How to REVERSE rotation with glRotatef() in iPhone OpenGL ES?
body: <p>I am trying to rotate a 3D model in both forward (counter-clockwise) and reverse (clockwise) rotation directions in orthographic mode. glRotatef() automatically executes a forward rotation but I cannot get a <strong><em>reverse</em></strong> rotation. I have tried the following methods and none of them give me results:</p>
  
  <pre><code>   //(Provide a negative rotation angle of -1 degree)
      glrotatef(-1.0, 0.0, 1.0, 0.0);
  
      //(Set a negative axis)
      glrotatef(1.0, 0.0, -1.0, 0.0);
  </code></pre>
  
  <p>Is this a limitation in OpenGL ES 1.1? How can I get REVERSE (clockwise) rotation in OpenGL ES?</p>