Marker label overlapping when two markers are close to each other. How to give background color to google maps marker?

Question

I am using google maps version 3 api and google maps marker. When the markers are close to each other the labels overlap and it looks bad. I was trying to give background color to the marker label but google maps marker label does not seem to have background color property. I tried using MarkerWithLabel api but rendering was slower when I had 1000s of markers compared to google maps deafult Marker Label. I have included the js fiddle. Can anyone please help me with this ?

https://jsfiddle.net/dcvc99qz/12/

function initMap() {
    var pointA = new google.maps.LatLng(51.2750, 1.0870),
        pointB = new google.maps.LatLng(51.2750, 0.8140),
        myOptions = {
            zoom: 5,
            center: pointA,
            mapTypeId: google.maps.MapTypeId.ROADMAP
        },
        map = new google.maps.Map(document.getElementById('map-canvas'), myOptions),
        markerA = new google.maps.Marker({
            position: pointA,
            title: "point A",
            label: "AA",
            map: map
        }),
        markerB = new google.maps.Marker({
            position: pointB,
            title: "point B",
            label: "BB",
            map: map
        });

}

initMap();

Answer 1

Markers are just images, you can't just change its background color, you have to define a new icon. First, prepare new transparent images with right colors. Then create new icon definitions.

var icons = {
  green: {
      // link to an image, use https if original site also uses https
      url: 'https://i.imgur.com/5Yd25Ga.png',

      // set size of an image
      size: new google.maps.Size(22, 40),

      // if an image is a sprite, set its relative position from 0, 0
      origin: new google.maps.Point(0, 0),

      // part of an image pointing on location on the map
      anchor: new google.maps.Point(11, 40),

      // position of text label on icon
      labelOrigin: new google.maps.Point(11, 10)
      },
  red: {
      // ...
      }
};

Documentation of icon properties

When adding new marker set its icon to one of defined icons.

markerB = new google.maps.Marker({
    position: pointB,
    title: "point B",
    label: "BB",
    icon: icons.green,
    map: map
});

When points are close to each other, you will notice that text labels are overlapping. To fix it, add increasing zIndex to every marker.

markerA = new google.maps.Marker({
    position: pointA,
    title: "point A",
    label: "AA",
    zIndex: 1000,
    icon: icons.red,
    map: map
});

markerB = new google.maps.Marker({
  position: pointB,
  title: "point B",
  label: "BB",
  zIndex: 1001,
  icon: icons.green,
  map: map
});

Full working example: jsfiddle.net/yLhbxnz6/