Image Map Types

This example uses image tiles of the moon's surface to create a map.

Read the documentation.

TypeScript

function initMap(): void {
  const map = new google.maps.Map(
    document.getElementById("map") as HTMLElement,
    {
      center: { lat: 0, lng: 0 },
      zoom: 1,
      streetViewControl: false,
      mapTypeControlOptions: {
        mapTypeIds: ["moon"],
      },
    }
  );

  const moonMapType = new google.maps.ImageMapType({
    getTileUrl: function (coord, zoom): string {
      const normalizedCoord = getNormalizedCoord(coord, zoom);

      if (!normalizedCoord) {
        return "";
      }

      const bound = Math.pow(2, zoom);
      return (
        "https://mw1.google.com/mw-planetary/lunar/lunarmaps_v1/clem_bw" +
        "/" +
        zoom +
        "/" +
        normalizedCoord.x +
        "/" +
        (bound - normalizedCoord.y - 1) +
        ".jpg"
      );
    },
    tileSize: new google.maps.Size(256, 256),
    maxZoom: 9,
    minZoom: 0,
    // @ts-ignore TODO(jpoehnelt) 'radius' does not exist in type 'ImageMapTypeOptions'
    radius: 1738000,
    name: "Moon",
  });

  map.mapTypes.set("moon", moonMapType);
  map.setMapTypeId("moon");
}

// Normalizes the coords that tiles repeat across the x axis (horizontally)
// like the standard Google map tiles.
function getNormalizedCoord(coord, zoom) {
  const y = coord.y;
  let x = coord.x;

  // tile range in one direction range is dependent on zoom level
  // 0 = 1 tile, 1 = 2 tiles, 2 = 4 tiles, 3 = 8 tiles, etc
  const tileRange = 1 << zoom;

  // don't repeat across y-axis (vertically)
  if (y < 0 || y >= tileRange) {
    return null;
  }

  // repeat across x-axis
  if (x < 0 || x >= tileRange) {
    x = ((x % tileRange) + tileRange) % tileRange;
  }

  return { x: x, y: y };
}

declare global {
  interface Window {
    initMap: () => void;
  }
}
window.initMap = initMap;

JavaScript

function initMap() {
  const map = new google.maps.Map(document.getElementById("map"), {
    center: { lat: 0, lng: 0 },
    zoom: 1,
    streetViewControl: false,
    mapTypeControlOptions: {
      mapTypeIds: ["moon"],
    },
  });
  const moonMapType = new google.maps.ImageMapType({
    getTileUrl: function (coord, zoom) {
      const normalizedCoord = getNormalizedCoord(coord, zoom);

      if (!normalizedCoord) {
        return "";
      }

      const bound = Math.pow(2, zoom);
      return (
        "https://mw1.google.com/mw-planetary/lunar/lunarmaps_v1/clem_bw" +
        "/" +
        zoom +
        "/" +
        normalizedCoord.x +
        "/" +
        (bound - normalizedCoord.y - 1) +
        ".jpg"
      );
    },
    tileSize: new google.maps.Size(256, 256),
    maxZoom: 9,
    minZoom: 0,
    // @ts-ignore TODO(jpoehnelt) 'radius' does not exist in type 'ImageMapTypeOptions'
    radius: 1738000,
    name: "Moon",
  });

  map.mapTypes.set("moon", moonMapType);
  map.setMapTypeId("moon");
}

// Normalizes the coords that tiles repeat across the x axis (horizontally)
// like the standard Google map tiles.
function getNormalizedCoord(coord, zoom) {
  const y = coord.y;
  let x = coord.x;
  // tile range in one direction range is dependent on zoom level
  // 0 = 1 tile, 1 = 2 tiles, 2 = 4 tiles, 3 = 8 tiles, etc
  const tileRange = 1 << zoom;

  // don't repeat across y-axis (vertically)
  if (y < 0 || y >= tileRange) {
    return null;
  }

  // repeat across x-axis
  if (x < 0 || x >= tileRange) {
    x = ((x % tileRange) + tileRange) % tileRange;
  }
  return { x: x, y: y };
}

window.initMap = initMap;

CSS

/* 
 * Always set the map height explicitly to define the size of the div element
 * that contains the map. 
 */
#map {
  height: 100%;
}

/* 
 * Optional: Makes the sample page fill the window. 
 */
html,
body {
  height: 100%;
  margin: 0;
  padding: 0;
}

HTML

<html>
  <head>
    <title>Image Map Types</title>
    <script src="https://polyfill.io/v3/polyfill.min.js?features=default"></script>

    <link rel="stylesheet" type="text/css" href="./style.css" />
    <script type="module" src="./index.js"></script>
  </head>
  <body>
    <div id="map"></div>

    <!-- 
     The `defer` attribute causes the callback to execute after the full HTML
     document has been parsed. For non-blocking uses, avoiding race conditions,
     and consistent behavior across browsers, consider loading using Promises
     with https://www.npmjs.com/package/@googlemaps/js-api-loader.
    -->
    <script
      src="https://maps.googleapis.com/maps/api/js?key=AIzaSyB41DRUbKWJHPxaFjMAwdrzWzbVKartNGg&callback=initMap&v=weekly"
      defer
    ></script>
  </body>
</html>

Try Sample

Clone Sample

Git and Node.js are required to run this sample locally. Follow these instructions to install Node.js and NPM. The following commands clone, install dependencies and start the sample application.

  git clone -b sample-maptype-image https://github.com/googlemaps/js-samples.git
  cd js-samples
  npm i
  npm start

Other samples can be tried by switching to any branch beginning with sample-SAMPLE_NAME.

  git checkout sample-SAMPLE_NAME
  npm i
  npm start