var directionsDisplay;
  var directionsService = new google.maps.DirectionsService();
  var map;
  var oldDirections = [];
  var currentDirections = null;


  function initialize() {
    var myOptions = {
      zoom: 11,
      center: new google.maps.LatLng(47.880650, 13.012072),
      mapTypeId: google.maps.MapTypeId.ROADMAP
    }
    map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);

    directionsDisplay = new google.maps.DirectionsRenderer({
        'map': map,
        'preserveViewport': true,
        'draggable': true
    });
    directionsDisplay.setPanel(document.getElementById("directions_panel"));

    google.maps.event.addListener(directionsDisplay, 'directions_changed',
      function() {
        if (currentDirections) {
          oldDirections.push(currentDirections);
        }
        currentDirections = directionsDisplay.getDirections();
      });
    calcRoute();
  }
  
  function getAddress(){
   s = document.getElementById("startAddress").value;
   t = document.getElementById("targetAddress").value;
   calcRoute();
  }


  function calcRoute() {
    //var start = '5020 Salzburg Theaterplatz';
	var start = s;
	var target = t;
    var end = t;
    var request = {
        origin:start,
        destination:end,
        travelMode: google.maps.DirectionsTravelMode.DRIVING
    };
    directionsService.route(request, function(response, status) {
      if (status == google.maps.DirectionsStatus.OK) {
        directionsDisplay.setDirections(response);
      }
    });
  }