title: can I make glsl bail out of a loop when it's been running too long?
body: <p>I'm doing some glsl fractals, and I'd like to make the calculations bail if they're taking too long to keep the frame rate up (without having to figure out what's good for each existing device and any future ones).</p>
  
  <p>It would be nice if there were a timer I could check every 10 iterations or something....</p>
  
  <p>Failing that, it seems the best approach might be to track how long it took to render the previous frame (or previous N frames) and change the "iterate to" number dynamically as a uniform...?</p>
  
  <p>Or some other suggestion? :)</p>