geodesic map for a single source and multiple destination gmap4 rails - ruby-on-rails

Question

I am new to gmaps4 and i have tried a lot but i was not able to find how to create a geodesic map, if i have single source and multiple destination using gmap4 rails.
So far i have tried this
Js
var locations = [
//Starting Point is "Home", and links to other locations"//
['Home', 37.774930, -122.419416],
['Location-1', 35.689487, 139.691706],
['Location-2', 48.856614, 2.352222],
['Location-3', -33.867487, 151.206990]
]
function initMap() {
var myLatLng = {
lat: 12.363,
lng: -131.044
};
var map = new google.maps.Map(document.getElementById('map'), {
zoom: 3,
mapTypeId: google.maps.MapTypeId.ROADMAP,
center: {
lat: 0,
lng: 0
}
});
var markers = [];
var bounds = new google.maps.LatLngBounds();
// Add the markers and infowindows to the map
for (var i = 0; i < locations.length; i++) {
var marker = new google.maps.Marker({
position: new google.maps.LatLng(locations[i][1], locations[i][2]),
title: locations[i][0],
map: map
})
markers.push(marker);
bounds.extend(marker.getPosition());
if (i > 0) {
var sitepath = new google.maps.Polyline({
path: [markers[0].getPosition(), marker.getPosition()],
geodesic: true,
strokeColor: '#FF0000',
strokeOpacity: 1.0,
strokeWeight: 2,
map: map
});
}
}
map.fitBounds(bounds);
}
google.maps.event.addDomListener(window, "load", initMap);
Html
<div id="map"></div>
but i am not able to understand how to do it using gmaps4 rails