title: Not rendering when there is no update battery optimisation - libgdx
body: <p>I'm looking a minimising battery usage in a game I'm developing, and battery usage is something that's very hard to measure accurately, so I was hoping someone in the know might be able to answer this.</p>
  
  <p>Is it likely to be worth my implementing a system where I don't render when there are no updates to what's displayed on the screen? Something like</p>
  
  <pre><code>updated = false;
  
  for each component
    updated |= component.update();
  
  if (updated)
    render();
  </code></pre>
  
  <p>This is the kind of thing that's much easier to add at the start, if it'll be worthwhile, than to try to add in at the end if it's required.</p>
  
  <p>If I was rendering through the CPU then I'd definitely say it was worth doing, but through the GPU I'm not so sure. Will in save an insignificant amount of battery compared to things like the screen being on?</p>
  
  <p><strong>edit:</strong>
  A bit of clarification. I'm creating a word game, so a lot of the time the user is going to be staring at a motionless screen looking for words. Depending on the mode the game is being played in, something could happen on the screen that isn't triggered by user input. For example, a new object appearing on the screen every 5 seconds. Rendering 300 frames where nothing happens every 5 seconds seems a real waste and is something I'd like to avoid.</p>