I'm not a graphics expert, but one really easy change to make is a pattern like this:

    _needsrender = false;
    
    function render () {
        _needsrender = true;
    }

    requestAnimationFrame(function hardrender () {
         if (_needsrender) { 
          .... do stuff ....
          _needsrender = false;
         }
         requestAnimationFrame(hardrender);
    });