docs: function(positioningHeading) {
      var heading = positioningHeading.magneticHeading * -1;
  
      if (!_heading || _heading === 0) {
        _heading = heading;
        _continuousHeading = heading;
        _smoothHeading = heading;
        return;
      }
  
      var diff = heading - _heading;
      if (Math.abs(diff) >= DIFF_THRESHOLD) {
        var add = diff > 0 ? -360 : 360;
        _diffAddition+= add;
      }
  
      _heading = heading
      _continuousHeading = heading + _diffAddition;
    }