Update position for a list of marker

Question

I am working with google maps, for been specific, I am working with http://hpneo.github.io/gmaps for a gps tracker simulation, here I need to update the position on each point. At the gmaps script, markers are stored on an array, and then I was thinking on take each point and use the setPoint method for update the position, however, the gmaps scripts doesn't have implemented this method. I was thinking on implement this method, but my question is then: After having an array of markers on the gmaps script, how could I identify each one in order to update position on the correct marker O r probably I must store it on an external array, an associative array which help me to identifies each marker, but I am thinking that when I update them, the array on the gmap script also will be keeping at the same position without been updated I am attaching my code

/** Positions and map statuses **/
var isLoaded = false;
/** **/
var refreshIntervalId;
var vehicles;
var map;
function setVehicleAsCenter (registration) {
    alert("Hola");
}
function loadPoints (positions) {
    console.debug('loading markers');
    var lttd;
    var lgtd;
    for (var i=0; i < positions.length; i++) {
        lttd = positions[i].latitude;
        lgtd = positions[i].longitude;
        marker = map.addMarker({
            lat: lttd,
            lng: lgtd,
        });
        markers[positions[i].registration] = marker;
    };
    map.fitZoom();
    isLoaded = true
}
function updatePoints (positions) {
    /**
    how could be the alorithm here
    */
    console.debug('updating markers');
}
function requestPoints() {
    $.ajax({
        url:'{% url 'gpstracking.ajax.request_tracks' %}',
        type: 'get',
        dataType: 'json',
        data: {
            vehicles: vehicles
        },
        success: function (positions) {
            if (isLoaded == false) {
                loadPoints (positions);
            } else {
                updatePoints (positions);
            }
        }
    });
}
$(document).ready(function() {
    /** Buttons Click Event Set **/
    $('.map-mode').click(function(){
        vehicles = '';
        $("#jstree").jstree("get_checked",null,true).find('a[rel="vehicle"]').each(function(){
            vehicles =  vehicles + $.trim(this.text) + "|";
        });
        if (vehicles == '') {
            console.debug('No vehicles to display');
            return;
        }
        option = $(this).attr('rel');
        if (option == 'show') {
            console.debug('Ordering to show');
            clearInterval(refreshIntervalId);
            requestPoints();
        }
        if (option == 'listen') {
            console.debug('Listening');
            requestPoints();
            refreshIntervalId = setInterval("requestPoints()", 10000);
        }
        if (option == 'clear') {
            console.debug('Clearing');
            clearInterval(refreshIntervalId);
            markers = new Object();
            map.removeMarkers();
            isLoaded = false;
        }
    });
    /** Map loading **/
    map = new GMaps({
        div: '#map-canvas',
        lat: -16.4237766667,
        lng: -71.54262,
    });
});

Answer 1

Google map markers expose a setPosition method for this.

I'm guessing that the markers variable is declared somewhere and is keeping a reference to each marker on the map:

function updatePoints (positions) {
    for (var i=0; i < positions.length; i++) {
        var pos=positions[i];
        var marker=markers[pos.registration];
        if(marker){
            // this marker already exists, so reposition it
            var latlong=new google.maps.LatLng(pos.latitude, pos.longitude);
            marker.setPosition(latlong);
        }else{
            // this is a new marker so create it
            marker = map.addMarker({
                lat: pos.latitude,
                lng: pos.longitude,
            });
            markers[pos.registration] = marker;
        }
    }
}