Calculating the distance between 4 locations [duplicate] - google-maps-api-3

Question

I'm trying to calculate the total distance for a route with a single waypoint in it, but somehow my code only returns the distance to the first waypoint instead of the total distance.
Here's my code:
function calcRoute(homebase,from,to,via){
var start = from;
var end = to;
var wypt = [ ];
wypt.push({
location:via,
stopover:true});
var request = {
origin:start,
destination:end,
waypoints:wypt,
optimizeWaypoints: true,
travelMode: google.maps.DirectionsTravelMode.DRIVING,
unitSystem: google.maps.DirectionsUnitSystem.METRIC
};
directionsService.route(request, function(response, status) {
if (status == google.maps.DirectionsStatus.OK) {
directionsDisplay.setDirections(response);
var distance = response.routes[0].legs[0].distance.text;
var time_taken = response.routes[0].legs[0].duration.text;
var calc_distance = response.routes[0].legs[0].distance.value;
}
});
}

Answer 1

The reason you only get the distance for legs[0] is because that is what your code is calculating. You need to sum up the distances of all the legs:
http://www.geocodezip.com/v3_GoogleEx_directions-waypoints_totalDist.html
code snippet:
var directionDisplay;
var directionsService = new google.maps.DirectionsService();
var map;
function initialize() {
directionsDisplay = new google.maps.DirectionsRenderer();
var chicago = new google.maps.LatLng(41.850033, -87.6500523);
var myOptions = {
zoom: 6,
mapTypeId: google.maps.MapTypeId.ROADMAP,
center: chicago
}
map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);
directionsDisplay.setMap(map);
calcRoute();
}
google.maps.event.addDomListener(window, 'load', initialize);
function calcRoute() {
var request = {
// from: Blackpool to: Preston to: Blackburn
origin: "Blackpool,UK",
destination: "Blackburn,UK",
waypoints: [{
location: "Preston,UK",
stopover: true
}],
optimizeWaypoints: true,
travelMode: google.maps.DirectionsTravelMode.WALKING
};
directionsService.route(request, function(response, status) {
if (status == google.maps.DirectionsStatus.OK) {
directionsDisplay.setDirections(response);
var route = response.routes[0];
var summaryPanel = document.getElementById("directions_panel");
summaryPanel.innerHTML = "";
// For each route, display summary information.
for (var i = 0; i < route.legs.length; i++) {
var routeSegment = i + 1;
summaryPanel.innerHTML += "<b>Route Segment: " + routeSegment + "</b><br />";
summaryPanel.innerHTML += route.legs[i].start_address + " to ";
summaryPanel.innerHTML += route.legs[i].end_address + "<br />";
summaryPanel.innerHTML += route.legs[i].distance.text + "<br /><br />";
}
computeTotalDistance(response);
} else {
alert("directions response " + status);
}
});
}
function computeTotalDistance(result) {
var totalDist = 0;
var totalTime = 0;
var myroute = result.routes[0];
for (i = 0; i < myroute.legs.length; i++) {
totalDist += myroute.legs[i].distance.value;
totalTime += myroute.legs[i].duration.value;
}
totalDist = totalDist / 1000.
document.getElementById("total").innerHTML = "total distance is: " + totalDist + " km<br>total time is: " + (totalTime / 60).toFixed(2) + " minutes";
}
html {
height: 100%
}
body {
height: 100%;
margin: 0px;
padding: 0px
}
<script src="https://maps.google.com/maps/api/js?key=AIzaSyCkUOdZ5y7hMm0yrcCQoCvLwzdM6M8s5qk"></script>
<div id="map_canvas" style="float:left;width:70%;height:100%;"></div>
<div id="control_panel" style="float:right;width:30%;text-align:left;padding-top:20px">
<div id="directions_panel" style="margin:20px;background-color:#FFEE77;"></div>
<div id="total"></div>
</div>