Google maps/gmap3 - plotting a route to a known destination from a user's geolocation

i'm trying to write a script that will get a user's geolocation - if they have it enabled, and plot a route to a predefined destination. if they don't have geolocation enabled, it should just plot the predefined location. the script isn't working - it's getting to the alert in getLocation() but that's about it. you should be able to get a good idea of what i'm trying do do by looking through the code. am i on the right track? can anyone spot why it isn't working? i'm fairly new to javascript so help would be much appreciated.

[COLOR=#000000][FONT=Arial]
[/FONT][/COLOR][COLOR=#800000]<script[/COLOR] [COLOR=#FF0000]type[/COLOR]=[COLOR=#0000FF]"text/javascript"[/COLOR][COLOR=#800000]>[/COLOR]
       $([COLOR=#00008B]function[/COLOR] (){

        [COLOR=#00008B]var[/COLOR] dest = [COLOR=#800000]"Tallaght Business Centre, Whitestown Rd, Tallaght Business Park, Dublin 24, Co. Dublin, Ireland"[/COLOR];

        [COLOR=#00008B]if[/COLOR](geolocEnabled()){
            getLocation();
            plotRoute();
        }[COLOR=#00008B]else[/COLOR]{
            plotMarker();
        }

        [COLOR=gray]//check if geolocation enabled[/COLOR]
        [COLOR=#00008B]function[/COLOR] geolocEnabled(){
            [COLOR=#00008B]return[/COLOR] navigator.geolocation;
        }

        [COLOR=gray]//plot marker for VRF office[/COLOR]
        [COLOR=#00008B]function[/COLOR] plotMarker(dest){
            $([COLOR=#800000]'#map'[/COLOR]).gmap3(
              { action: [COLOR=#800000]'addMarker'[/COLOR],
                address: dest,
                map:{
                  center: [COLOR=#00008B]true[/COLOR],
                  zoom: [COLOR=#800000]14[/COLOR]
                },
                marker:{
                  options:{
                    draggable: [COLOR=#00008B]false[/COLOR]
                  }
                }
              }
            );
        }

        [COLOR=gray]//get user's location[/COLOR]
        [COLOR=#00008B]function[/COLOR] getLocation(){
            $([COLOR=#800000]'#map'[/COLOR]).gmap3(
            { action : [COLOR=#800000]'geoLatLng'[/COLOR],
              callback : [COLOR=#00008B]function[/COLOR](latLng){
                [COLOR=#00008B]if[/COLOR] (latLng){
                  [COLOR=gray]//var userLocation = latLang; [/COLOR]
                  [COLOR=#00008B]return[/COLOR];
                } [COLOR=#00008B]else[/COLOR] {
                  alert([COLOR=#800000]"Unable to determine your location. Enable geolocation services\n and try again, or consult the map for out location."[/COLOR]);
                }
              }
            });
          }

        [COLOR=gray]//plot route[/COLOR]
        [COLOR=#00008B]function[/COLOR] plotRoute(latLng, dest){
        $([COLOR=#800000]'#map'[/COLOR]).gmap3(
          { action:[COLOR=#800000]'getRoute'[/COLOR],
            options:{
              origin: latLng,
              destination: dest,
              travelMode: google.maps.[COLOR=#2B91AF]DirectionsTravelMode[/COLOR].DRIVING
            },
            callback: [COLOR=#00008B]function[/COLOR](results){
              [COLOR=#00008B]if[/COLOR] (!results) [COLOR=#00008B]return[/COLOR];
              $([COLOR=#00008B]this[/COLOR]).gmap3(
                { action:[COLOR=#800000]'init'[/COLOR], 
                  zoom: [COLOR=#800000]13[/COLOR], 
                  mapTypeId: google.maps.[COLOR=#2B91AF]MapTypeId[/COLOR].ROADMAP, 
                  streetViewControl: [COLOR=#00008B]true[/COLOR]
                  [COLOR=gray]//center: [-33.879, 151.235] [/COLOR]
                },
                { action:[COLOR=#800000]'addDirectionsRenderer'[/COLOR],
                  options:{
                    panelID: [COLOR=#800000]'directions-panel'[/COLOR],
                    preserveViewport: [COLOR=#00008B]true[/COLOR],
                    draggable: [COLOR=#00008B]false[/COLOR],
                    directions:results
                  }
                }
              );
            }
          }
        );
      }

      [COLOR=gray]//on click show directions from origin to destination in directions panel[/COLOR]
      $([COLOR=#800000]'#show-directions-button'[/COLOR]).click([COLOR=#00008B]function[/COLOR](){
        $([COLOR=#800000]'#map'[/COLOR]).gmap3({
          action: setDirectionsPanel,
          id: directions-panel
        });
      });

    });
    [COLOR=#800000]</script>[/COLOR]

Code (markup):