/**
  * Renders the map javascript polylines
  *
  * @param Ivory\GoogleMapBundle\Model\Map $map
  * @return string HTML output
  */
 public function renderPolylines(Map $map)
 {
     $html = array();
     foreach ($map->getPolylines() as $polyline) {
         $html[] = $this->polylineHelper->render($polyline, $map);
     }
     return implode('', $html);
 }