urlRoute0 = './application/helpers/prefetch.route.php?r=sauer_track.geojson&light='+slowMobileConnection+'&fingerprint=YX5XLjDFujOj841h1WgtQGJGBpDQnyU1_mod_1740324175';

                        map.addSource('route0', {
                            type: 'geojson',
                            data: urlRoute0                        });

                        map.addLayer({
                            "id": "route0",
                            "type": "line",
                            "source": "route0",
                            "layout": {
                                "line-join": "round",
                                "line-cap": "round"
                            },
                            "paint": {
                                "line-color": "#551a8b",
                                "line-width": 3                            }
                        });

                        
                            map.addLayer({
                              'id': 'arrow-layer0',
                              'type': 'symbol',
                              'source': 'route0',
                              'layout': {
                                'symbol-placement': 'line',
                                'symbol-spacing': 200,
                                'icon-allow-overlap': true,
                                'icon-image': 'route-direction-arrow',
                                'icon-size': 0.3,
                                'visibility': 'visible'
                              },
                              'paint': {
                                'icon-color': '#551a8b',
                              }
                            });