title: gameloop framerate control issues
body: <p>this is driving me mad, anyway, usual story, attempting to guarantee the same speed in my very simple game across any windows machine that runs it. im doing it by specifying a 1/60 value, then ensuring a fram cant run until that value has passed in time since the last time it was called. the problem im having is 1/60 equates to 30hz for some reason, I have to set it to 1/120 to get 60hz. its also not bang on 60hz, its a little faster.</p>
  
  <p>if i paste it out here, could someone tell me if they see anything wrong? or a more precise way to do it maybe?</p>
  
  <pre><code>float controlFrameRate = 1./60 ;
  
  while (gameIsRunning)
  {
      frameTime += (system-&gt;getElapsedTime()-lastTime);
      lastTime = system-&gt;getElapsedTime();
  
      if(frameTime &gt; controlFrameRate)
      {
          gameIsRunning = system-&gt;update();
          
          //do stuff with the game
  
          frameTime = .0f;                   
      }
  } 
  </code></pre>