text: var bottle = null;
  window.addEventListener('load', function() {
      bottle = new Bottle(document.getElementById('display'));
      function step() {
          bottle.step();
      }
      function render() {
          bottle.render();
          window.requestAnimationFrame(render);
      }
      window.requestAnimationFrame(render);
      setInterval(step, 1000 / Bottle.FPS);
  
      document.getElementById('doBlur')
          .addEventListener('change', function() {
              bottle.doBlur = this.checked;
          });
      document.getElementById('doThreshold')
          .addEventListener('change', function() {
              bottle.doThreshold = this.checked;
          });
  });
  