Develop Reference

Cant get my marker's latLng to use in L.Routing.control

guys
I been trying to get my markers latlon when user double click on it but still don't get any results. Been trying other methods but i think this is the most accurate since i dont get any error when executing js
Any recommendation pls
var places = [
["LOCATION_1", 8.9856146341374, -79.51102268985925],
["LOCATION_2", 8.984640842221594, -79.51383510471848],
["LOCATION_3", 8.972080043026754, -79.5529245611453],
["LOCATION_4", 9.052896045979661, -79.4515923525883],
["LOCATION_5", 9.053366385577624, -79.50832832626823]
];
var map = L.map('map', {
center: [9.352867999999996, -79.689331],//[35.791188, -78.636755],
zoom: 9,
layers:L.tileLayer('http://{s}.google.com/vt/lyrs=m&x={x}&y={y}&z={z}',{
maxZoom: 20,
subdomains:['mt0','mt1','mt2','mt3']
})
});
for (var i = 0; i < places.length; i++) {
marker = new L.marker([places[i][1], places[i][2]])
.bindPopup(places[i][0])
.addTo(map);
}
function getdest(){
L.marker.on('dblclick',function(e){
var latlng_dest=e.latlng() });
console.log(latlng_dest)
return latlng_dest
}
navigator.geolocation.getCurrentPosition(function(location) {
var latlng_orig = new L.LatLng(location.coords.latitude, location.coords.longitude);
L.Routing.control({
waypoints: [
//L.latLng(9.10607301250145, -79.34754531445351),
L.latLng(latlng_orig)
//,L.latLng(latlng_dest)
//,L.latLng(9.100769244670843, -79.35099352767948)
,L.latLng(getdest())
]
}).addTo(map)
});

You have many common things wrong:
e.latlng() is not a function it is a property e.latlng
L.marker.on('dblclick',function(e){ this makes no sense. You creating a new instance of a Marker without coords and then adding a listener to it.
You can't return a value in a function from a listener. The listener is not called at the moment you return the value L.marker.on('dblclick',function(e){ var latlng_dest=e.latlng() }); return latlng_dest
Your code should look like that:
for (var i = 0; i < places.length; i++) {
marker = new L.marker([places[i][1], places[i][2]])
.bindPopup(places[i][0])
.addTo(map)
.on('dblclick', function(e) {
waypoints.push(e.latlng);
routeControl.setWaypoints(waypoints);
});
}
var routeControl = L.Routing.control({
waypoints: [],
}).addTo(map);
var waypoints = [];
navigator.geolocation.getCurrentPosition(function(location) {
var latlng_orig = new L.LatLng(location.coords.latitude, location.coords.longitude);
waypoints.push(latlng_orig);
});

returning object from a javascript function with database query inside

I am trying to return the markers as the object but when i run the function it just returns [ ], but printing it inside i can see the object data, can anyone explain how to return the object batch2 please?
google.maps.event.addListener(mgr, 'loaded', function(){
mgr.addMarkers(getMarkers(),6); //add all the markers! documentation for viewports with totals for city count, look at viewport
mgr.addMarkers(getMarkers2(),14); //get markers for zoomed out place, add click function to zoom in
//mgr.addMarkers(getMarkers(1000), 8);
console.log("added");
mgr.refresh();
});
function getMarkers2() {
var batch2 = [];
var clusters = new Parse.Query("cityfreqcoords");
var clusterresults = new Parse.Object("cityfreqcoords");
clusters.find({
success: function (results) {
for (i = 1; i < results.length; i++) {
var city = (results[i]["attributes"]["city"]);
var count = (results[i]["attributes"]["count"]);
var lat = (results[i]["attributes"]["lat"]);
var lng = (results[i]["attributes"]["lng"]);
var markerLatlong = new google.maps.LatLng(lat, lng);
//icon =
//adding the marker
var marker2 = new google.maps.Marker({
position: markerLatlong,
title: city,
clickable: true,
animation: google.maps.Animation.DROP
//icon:icon
});
//adding the click event and info window
google.maps.event.addListener(marker2, 'click', function () {
map.setZoom(6);
map.setCenter(marker2.getPosition());
});
batch2.push(marker2);
}
}
})
return batch2;
}

It would appear that clusters.find is asynchronous. You return batch2 before cluster.find succeeds. There are a handful of patterns for working with asynchronous code in JavaScript -- one common one is to use a callback. You would need to rewrite your code like so:
function getMarkers2(callback) {
var batch2 = [];
var clusters = new Parse.Query("cityfreqcoords");
var clusterresults = new Parse.Object("cityfreqcoords");
clusters.find({
success: function (results) {
for (i = 1; i < results.length; i++) {
var city = (results[i]["attributes"]["city"]);
var count = (results[i]["attributes"]["count"]);
var lat = (results[i]["attributes"]["lat"]);
var lng = (results[i]["attributes"]["lng"]);
var markerLatlong = new google.maps.LatLng(lat, lng);
//icon =
//adding the marker
var marker2 = new google.maps.Marker({
position: markerLatlong,
title: city,
clickable: true,
animation: google.maps.Animation.DROP
//icon:icon
});
//adding the click event and info window
google.maps.event.addListener(marker2, 'click', function () {
map.setZoom(6);
map.setCenter(marker2.getPosition());
});
batch2.push(marker2);
}
}
callback(batch2);
})
}
Then call it like so:
getMarkers2(function(markers) {
mgr.addMarkers(markers, 14);
});
If you're interested, take a look at how promises work as you might prefer that approach over using callbacks.

With callbacks in javascript, you generally don't return data. You pass in another function reference into the handler as a callback.
EG:
function getMarkers2(f) {
// do stuff
//when done
f(batch2)
}

Ended up just passing making the marker manager global and passing mgr into the query which worked, probably not the most efficient way to do it
function getMarkers2(mgr) {
Parse.initialize("X", "Y");
var batch2 = [];
var clusters = new Parse.Query("cityfrequency2");
var clusterresults = new Parse.Object("cityfrequency2");
clusters.find({
success: function (results) {
for (i = 0; i < (results.length); i++) {
var city = (results[i]["attributes"]["city"]);
var lat = (results[i]["attributes"]["lat"]);
var lng = (results[i]["attributes"]["lng"]);
var markerLatlong = new google.maps.LatLng(lat, lng);
var image = {
url: 'warning.png',
size: new google.maps.Size(50, 46),
// The origin
origin: new google.maps.Point(0, 0),
// The anchor
anchor: new google.maps.Point(25, 0)
};
//adding the marker
var marker2 = new google.maps.Marker({
position: markerLatlong,
title: city,
clickable: true,
animation: google.maps.Animation.DROP,
icon:image
});
//adding the click event and info window
google.maps.event.addListener(marker2, 'click', function () {
map.setZoom(6);
map.setCenter();
});
batch2.push(marker2);
mgr.addMarkers(batch2,0,6);
mgr.refresh();
}
}
})
}
function setupMarkers() {
var mgrOptions = { borderPadding: 50, maxZoom: 15, trackMarkers: true };
mgr = new MarkerManager(map,mgrOptions);
google.maps.event.addListener(mgr, 'loaded', function(){
getMarkers2(mgr);
getMarkers(mgr);
console.log("added");
});
}

Markers image are not displaying, only the last one because of css

I have a google map which was working well until a few weeks ago.
My problem is that now, all the label markers appears in the right place but only the last image appears.
I see in the generated html code that all images are here but all of them have the same position (that's why i can just see the last one).
I say again : it was working before, i'm sure! Maybe google has changed something (i'm calling the script : https://maps.googleapis.com/maps/api/js?sensor=false).
Here is my code :
jQuery(function() {
var stops = [];
var nbPoints = $('#nbPoints').val();
for (var i = 1; i <= nbPoints; i++) {
if($('#latitude'+i).val() && $('#longitude'+i).val())
stops.push({"Geometry":{"Latitude":$('#latitude'+i).val(),"Longitude":$('#longitude'+i).val()}});
}
var map = new window.google.maps.Map(document.getElementById("map_canvas"));
// new up complex objects before passing them around
var directionsDisplay = new window.google.maps.DirectionsRenderer({suppressMarkers: true});
var directionsService = new window.google.maps.DirectionsService();
Tour_startUp(stops);
window.tour.loadMap(map, directionsDisplay);
window.tour.fitBounds(map);
if (stops.length > 1)
window.tour.calcRoute(directionsService, directionsDisplay);
else $("#message").html("Erreur : Aucune coordonnée renseignée!");
});
function Tour_startUp(stops) {
if (!window.tour) window.tour = {
updateStops: function (newStops) {
stops = newStops;
},
// map: google map object
// directionsDisplay: google directionsDisplay object (comes in empty)
loadMap: function (map, directionsDisplay) {
var myOptions = {
zoom: 13,
center: new window.google.maps.LatLng($('#latitudeInit').val(),$('#longitudeInit').val()),
mapTypeId: window.google.maps.MapTypeId.ROADMAP
};
map.setOptions(myOptions);
directionsDisplay.setMap(map);
},
fitBounds: function (map) {
var bounds = new window.google.maps.LatLngBounds();
// extend bounds for each record
jQuery.each(stops, function (key, val) {
var myLatlng = new window.google.maps.LatLng(val.Geometry.Latitude, val.Geometry.Longitude);
bounds.extend(myLatlng);
});
map.fitBounds(bounds);
},
calcRoute: function (directionsService, directionsDisplay) {
var batches = [];
var itemsPerBatch = 10; // google API max = 10 - 1 start, 1 stop, and 8 waypoints
var itemsCounter = 0;
var wayptsExist = stops.length > 0;
while (wayptsExist) {
var subBatch = [];
var subitemsCounter = 0;
for (var j = itemsCounter; j < stops.length; j++) {
subitemsCounter++;
subBatch.push({
location: new window.google.maps.LatLng(stops[j].Geometry.Latitude, stops[j].Geometry.Longitude),
stopover: true
});
if (subitemsCounter == itemsPerBatch)
break;
}
itemsCounter += subitemsCounter;
batches.push(subBatch);
wayptsExist = itemsCounter < stops.length;
// If it runs again there are still points. Minus 1 before continuing to
// start up with end of previous tour leg
itemsCounter--;
}
// now we should have a 2 dimensional array with a list of a list of waypoints
var combinedResults;
var unsortedResults = [{}]; // to hold the counter and the results themselves as they come back, to later sort
//var directionsResultsReturned = 0;
var directionsResultsReturned = new Array();
directionsResultsReturned[0]=0;
for (var k = 0; k < batches.length; k++) {
var lastIndex = batches[k].length - 1;
var start = batches[k][0].location;
var end = batches[k][lastIndex].location;
// trim first and last entry from array
var waypts = [];
waypts = batches[k];
waypts.splice(0, 1);
waypts.splice(waypts.length - 1, 1);
var request = {
origin: start,
destination: end,
waypoints: waypts,
travelMode: window.google.maps.TravelMode.DRIVING
};
creerRoute(k,request,batches,directionsService,unsortedResults,combinedResults,directionsResultsReturned,directionsDisplay);
}
}
};
}
var infowindow = new google.maps.InfoWindow(
{
size: new google.maps.Size(150,50)
});
var icons = new Array();
icons["red"] = new google.maps.MarkerImage("mapIcons/marker_red.png",
// This marker is 20 pixels wide by 34 pixels tall.
new google.maps.Size(20, 34),
// The origin for this image is 0,0.
new google.maps.Point(0,0),
// The anchor for this image is at 9,34.
new google.maps.Point(9, 34));
function getMarkerImage(numero, type, anomalie) {
var url_img = "../img/";
var type = new String(type);
if(anomalie) url_img+="anomalie.png";
else{
switch(type.toUpperCase()){
case "LAVAGE" : url_img+="shower.png"; break;
case "EAU" : url_img+="waterdrop.png"; break;
default : url_img+="stop.png"; break;
}
}
icons[numero] = new google.maps.MarkerImage(url_img,
new google.maps.Size(34, 34),
new google.maps.Point(0,0),
new google.maps.Point(9, 34));
return icons[numero];
}
// Marker sizes are expressed as a Size of X,Y
// where the origin of the image (0,0) is located
// in the top left of the image.
// Origins, anchor positions and coordinates of the marker
// increase in the X direction to the right and in
// the Y direction down.
var iconImage = new google.maps.MarkerImage('mapIcons/marker_red.png',
// This marker is 20 pixels wide by 34 pixels tall.
new google.maps.Size(34, 34),
// The origin for this image is 0,0.
new google.maps.Point(0,0),
// The anchor for this image is at 9,34.
new google.maps.Point(9, 34));
var iconShadow = new google.maps.MarkerImage('http://www.google.com/mapfiles/shadow50.png',
// The shadow image is larger in the horizontal dimension
// while the position and offset are the same as for the main image.
new google.maps.Size(37, 34),
new google.maps.Point(0,0),
new google.maps.Point(9, 34));
// Shapes define the clickable region of the icon.
// The type defines an HTML <area> element 'poly' which
// traces out a polygon as a series of X,Y points. The final
// coordinate closes the poly by connecting to the first
// coordinate.
var iconShape = {
coord: [9,0,6,1,4,2,2,4,0,8,0,12,1,14,2,16,5,19,7,23,8,26,9,30,9,34,11,34,11,30,12,26,13,24,14,21,16,18,18,16,20,12,20,8,18,4,16,2,15,1,13,0],
type: 'poly'
};
function createMarker(map, latlng, label, html, numero, type, anomalie) {
var contentString = '<b>'+label+'</b><br>'+html;
var marker = new MarkerWithLabel({
position: latlng,
map: map,
draggable: false,
raiseOnDrag: true,
icon : getMarkerImage(numero,type,anomalie),
labelContent: numero,
labelAnchor: new google.maps.Point(0, 0),
labelClass: "labels",
labelInBackground: false
});
marker.myname = label;
google.maps.event.addListener(marker, 'click', function() {
infowindow.setContent(contentString);
infowindow.open(map,marker);
});
return marker;
}
function creerRoute(kk,request,batches,directionsService,unsortedResults,combinedResults,directionsResultsReturned,directionsDisplay) {
directionsService.route(request, function (result, status) {
if (status == window.google.maps.DirectionsStatus.OK) {
var unsortedResult = { order: kk, result: result };
unsortedResults.push(unsortedResult);
directionsResultsReturned[0]++;
if (directionsResultsReturned[0] == batches.length) // we've received all the results. put to map
{
// sort the returned values into their correct order
unsortedResults.sort(function (a, b) { return parseFloat(a.order) - parseFloat(b.order); });
var count = 0;
for (var key in unsortedResults) {
if (unsortedResults[key].result != null) {
if (unsortedResults.hasOwnProperty(key)) {
if (count == 0) // first results. new up the combinedResults object
combinedResults = unsortedResults[key].result;
else {
// only building up legs, overview_path, and bounds in my consolidated object. This is not a complete
// directionResults object, but enough to draw a path on the map, which is all I need
combinedResults.routes[0].legs = combinedResults.routes[0].legs.concat(unsortedResults[key].result.routes[0].legs);
combinedResults.routes[0].overview_path = combinedResults.routes[0].overview_path.concat(unsortedResults[key].result.routes[0].overview_path);
combinedResults.routes[0].bounds = combinedResults.routes[0].bounds.extend(unsortedResults[key].result.routes[0].bounds.getNorthEast());
combinedResults.routes[0].bounds = combinedResults.routes[0].bounds.extend(unsortedResults[key].result.routes[0].bounds.getSouthWest());
}
count++;
}
}
}
directionsDisplay.setDirections(combinedResults);
var legs = combinedResults.routes[0].legs;
for (var i=0; i < legs.length;i++){
var j = i + 1;
var markerletter = $('#ordre'+j).val();
var anomalie=false;
var html = $('#infospoint'+j).val();
if($('#infoschocspoint'+j).length){
anomalie = true;
html+="<br/>"+$('#infoschocspoint'+j).val();
}
createMarker(directionsDisplay.getMap(),legs[i].start_location,$('#titrepoint'+j).val(),html,markerletter,$('#type'+j).val(),anomalie);
}
var i=legs.length + 1;
var markerletter = $('#ordre'+i).val();
var anomalie=false;
var html = $('#infospoint'+i).val();
if($('#infoschocspoint'+i).length){
anomalie = true;
html+="<br/>"+$('#infoschocspoint'+i).val();
}
createMarker(directionsDisplay.getMap(),legs[legs.length-1].end_location,$('#titrepoint'+i).val(),html,markerletter,$('#type'+i).val(),anomalie);
}
}else {
if (status == window.google.maps.DirectionsStatus.OVER_QUERY_LIMIT) {
setTimeout( function(){
creerRoute(kk,request,batches,directionsService,unsortedResults,combinedResults,directionsResultsReturned,directionsDisplay);
}, 200);
}else{
$("#message").html("Erreur : Code "+status);
}
}
});
}
Has anyone the same problem?
Thanks for your help!

You can use new one
<script type="text/javascript" src="http://maps.google.com/maps/api/js?sensor=false&v=3.3"></script>

Remove markers out of viewport

I have to manage a map of about 80.000 markers concentrated in France.
To do that, I decided to get the bounds of the viewport and call a dynamic-JSON (with PHP) which contains the markers inside the viewport. And this on the "idle" event.
I faced a problem with this solution. Indeed, the markers which already exist was re-plotted (at the same position), which consequently weigh the map for nothing...
To solve it, the markers list before and after the JSON query are compared (thanks to jQuery), in order to plot only the new markers. And it works!
Now, I would want to remove the markers which are not currently shown on the map. Or a list of markers (I get it thanks to jQuery) designated by an ID which is also the title of the marker. So, how can a delete markers like that ? I specify that I am using MarkerManager.
Otherwise, you guess that if I do not remove these markers, they will be re-plotted in some cases... For example, you are viewing the city A, you move the map to view the city B, and you get back to the city A...
Here is the code:
var map;
var mgr;
var markers = [];
function initialize(){
var mapOptions = {
zoom: 6,
center: new google.maps.LatLng(46.679594, 2.109375)
};
map = new google.maps.Map(document.getElementById('map_canvas'), mapOptions);
var mgrOptions = { borderPadding: 50, maxZoom: 15, trackMarkers: false };
mgr = new MarkerManager(map, mgrOptions);
google.maps.event.addListener(map, 'idle', function() {
mapEvent();
});
}
function mapEvent(){
if( map.getZoom() >= 8 ){
var bounds = map.getBounds();
getSupports(bounds.getNorthEast(), bounds.getSouthWest());
} else {
// Todo
}
}
var markerslistID = new Array();
var markerslistData = {};
function getSupports(ne, sw){
newMarkerslistID = new Array();
newMarkerslistData = {};
// Getting the markers of the current view
$.getJSON('./markerslist.php?nelat='+ne.lat()+'&nelng='+ne.lng()+'&swlat='+sw.lat()+'&swlng='+sw.lng(), function(data) {
for (var i = 0; i < data.points.length; i++) {
var val = data.points[i];
newMarkerslistID.push(val.id);
newMarkerslistData[val.id] = new Array(val.lat, val.lng, val.icon);
}
// List of New Markers TO PLOT
var diffNewMarkers = $(newMarkerslistID).not(markerslistID).get();
// List of Old markers TO REMOVE
var diffOldMarkers = $(markerslistID).not(newMarkerslistID).get();
// Plotting the NEW MARKERS
for( var i = 0; i < diffNewMarkers.length; i++ ){
var marker = new google.maps.Marker({
position: new google.maps.LatLng(newMarkerslistData[diffNewMarkers[i]][0], newMarkerslistData[diffNewMarkers[i]][1]),
title : diffNewMarkers[i],
icon : './images/'+newMarkerslistData[diffNewMarkers[i]][2]+'.png'
});
mgr.addMarker(marker, 0);
}
/*****************************************
HERE WE HAVE TO REMOVE
THE MARKERS CONTAINED IN diffOldMarkers
*****************************************/
mgr.refresh();
// Switching the new list to the old, for the next event
markerslistID = newMarkerslistID;
markerslistData = newMarkerslistData;
});
}
Thank you for your help.

A one-liner to hide all markers that ar not in the current viewport.
!map.getBounds().contains(marker.getPosition()) && marker.setVisible(false);
Or,
if (map.getBounds().contains(marker.getPosition()) && !marker.getVisible()) {
marker.setVisible(true);
}
else if (!map.getBounds().contains(marker.getPosition()) && marker.getVisible()) {
marker.setVisible(false);
}

Show a moving marker on the map

I am trying to make a marker move(not disappear and appear again) on the map as a vehicle moves on the road.
I have two values of latLng and I want to move the marker between the two till the next point is sent by the vehicle. And then repeat the process again.
What I tried:[This is not a very efficient way, I know]
My thought was to implement the above using the technique in points below:
1) Draw a line between the two.
2) Get the latLng of each point on 1/10th fraction of the polyline.
3) Mark the 10 points on the map along with the polyline.
Here is my Code:
var isOpen = false;
var deviceID;
var accountID;
var displayNameOfVehicle;
var maps = {};
var lt_markers = {};
var lt_polyLine = {};
function drawMap(jsonData, mapObj, device, deleteMarker) {
var oldposition = null;
var oldimage = null;
var arrayOflatLng = [];
var lat = jsonData[0].latitude;
var lng = jsonData[0].longitude;
//alert(jsonData[0].imagePath);
var myLatLng = new google.maps.LatLng(lat, lng);
if (deleteMarker == true) {
if (lt_markers["marker" + device] != null) {
oldimage = lt_markers["marker" + device].getIcon().url;
oldposition = lt_markers["marker" + device].getPosition();
lt_markers["marker" + device].setMap(null);
lt_markers["marker" + device] = null;
}
else {
console.log('marker is null');
oldimage = new google.maps.MarkerImage(jsonData[0].imagePath,
null,
null,
new google.maps.Point(5, 17), //(15,27),
new google.maps.Size(30, 30));
oldposition = myLatLng;
}
}
var image = new google.maps.MarkerImage(jsonData[0].imagePath,
null,
null,
new google.maps.Point(5, 17), //(15,27),
new google.maps.Size(30, 30));
lt_markers["marker" + device] = new google.maps.Marker({
position: myLatLng,
icon: image,
title: jsonData[0].address
});
if (oldposition == myLatLng) {
alert('it is same');
lt_markers["marker" + device].setMap(mapObj);
mapObj.panTo(myLatLng);
}
else {
alert('it is not same');
var markMarker = null;
var i = 10;
for (i = 10; i <= 100; i + 10) {
//-------
// setTimeout(function() {
if (markMarker != null) {
markMarker.setMap(null);
markMarker = null;
}
alert('inside the loop');
var intermediatelatlng = mercatorInterpolate(mapObj, oldposition, myLatLng, i / 100);
alert('Intermediate Latlng is :' + intermediatelatlng);
arrayOflatLng.push(intermediatelatlng);
var flightPath = new google.maps.Polyline({
path: arrayOflatLng,
strokeColor: "#FFFFFF",
strokeOpacity: 1.0,
strokeWeight: 1
});
flightPath.setMap(mapObj);
if (i != 100) {
markMarker = new google.maps.Marker({
position: intermediatelatlng,
icon: image,
title: jsonData[0].address,
map: mapObj
});
}
else {
markMarker = new google.maps.Marker({
position: intermediatelatlng,
icon: oldimage,
title: jsonData[0].address,
map: mapObj
});
}
mapObj.panTo(intermediatelatlng);
//--------
// }, 1000);
}
}
}
function mercatorInterpolate(map, latLngFrom, latLngTo, fraction) {
// Get projected points
var projection = map.getProjection();
var pointFrom = projection.fromLatLngToPoint(latLngFrom);
var pointTo = projection.fromLatLngToPoint(latLngTo);
// Adjust for lines that cross the 180 meridian
if (Math.abs(pointTo.x - pointFrom.x) > 128) {
if (pointTo.x > pointFrom.x)
pointTo.x -= 256;
else
pointTo.x += 256;
}
// Calculate point between
var x = pointFrom.x + (pointTo.x - pointFrom.x) * fraction;
var y = pointFrom.y + (pointTo.y - pointFrom.y) * fraction;
var pointBetween = new google.maps.Point(x, y);
// Project back to lat/lng
var latLngBetween = projection.fromPointToLatLng(pointBetween);
return latLngBetween;
}
Problems Faced:
1) The marker is not showing up on the map because the process of plotting and removal of marker is so fast that the marker is not visisble on screen. I've tried setTimeOut, and It does not help at all.
2) if I alow the browser to run this code for more than 5 minutes, the browser crashes.
Note: The Above function is called every 10 seconds using setInterval.
What Can be a better solution? Please Help..

For the marker to move relatively smoothly, you need to
Update more than every 1/10 fraction of the polyline (at least every few pixels)
Call the update method more frequently
Don't delete and re-add the marker
For example, something like:
var counter = 0;
interval = window.setInterval(function() {
counter++;
// just pretend you were doing a real calculation of
// new position along the complex path
var pos = new google.maps.LatLng(35, -110 + counter / 100);
marker.setPosition(pos);
if (counter >= 1000) {
window.clearInterval(interval);
}
}, 10);
I made a simple example at http://jsfiddle.net/bmSbU/2/ which shows a marker moving along a straight path. If this is what you want, most of your code above regarding where along the line you are can be reused (or check out http://broady.github.io/maps-examples/points-along-line/along-directions.html )

You can use marker-animate-unobtrusive library to make markers
smoothly transition from one location to another (instead of reappearing).
You could initialize your marker like that:
var marker = new SlidingMarker({
//your original marker options
});
Just call marker.setPosition() each time new vehicle's coordinate arrive.
P.S. I'm the author of the library.

Why not keep the existing Marker/ MarkerImage and call setPosition() to move it, either on a timer or as the position changes?
Deleting it & recreating it is what causes it to flash/ flicker and eventually crash. If you keep the same instance but just move it, you should do much better.
See: Marker.setPosition()
https://developers.google.com/maps/documentation/javascript/reference#Marker