It's the 15th anniversary of Google Maps Platform - Check out the latest news and announcements

containsLocation()

This example draws a red circle when the clicked point falls outside of the specified polygon (the Bermuda Triangle), and a blue triangle when the click falls inside the polygon.

Read the documentation.

JavaScript

// This example requires the Geometry library. Include the libraries=geometry
// parameter when you first load the API. For example:
// <script src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&libraries=geometry">

function initMap() {
  var map = new google.maps.Map(document.getElementById("map"), {
    center: { lat: 24.886, lng: -70.269 },
    zoom: 5
  });

  var triangleCoords = [
    { lat: 25.774, lng: -80.19 },
    { lat: 18.466, lng: -66.118 },
    { lat: 32.321, lng: -64.757 }
  ];

  var bermudaTriangle = new google.maps.Polygon({ paths: triangleCoords });

  google.maps.event.addListener(map, "click", function(e) {
    var resultColor = google.maps.geometry.poly.containsLocation(
      e.latLng,
      bermudaTriangle
    )
      ? "blue"
      : "red";

    var resultPath = google.maps.geometry.poly.containsLocation(
      e.latLng,
      bermudaTriangle
    )
      ? // A triangle.
        "m 0 -1 l 1 2 -2 0 z"
      : google.maps.SymbolPath.CIRCLE;

    new google.maps.Marker({
      position: e.latLng,
      map: map,
      icon: {
        path: resultPath,
        fillColor: resultColor,
        fillOpacity: 0.2,
        strokeColor: "white",
        strokeWeight: 0.5,
        scale: 10
      }
    });
  });
}

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

<!DOCTYPE html>
<html>
  <head>
    <title>Polygon Contains Location</title>
    <script src="https://polyfill.io/v3/polyfill.min.js?features=default"></script>
    <script
      src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&callback=initMap&libraries=geometry&v=weekly"
      defer
    ></script>
    <link rel="stylesheet" type="text/css" href="./style.css" />
    <script src="./app.js"></script>
  </head>
  <body>
    <div id="map"></div>
  </body>
</html>

All

<!DOCTYPE html>
<html>
  <head>
    <title>Polygon Contains Location</title>
    <script src="https://polyfill.io/v3/polyfill.min.js?features=default"></script>
    <script
      src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&callback=initMap&libraries=geometry&v=weekly"
      defer
    ></script>
    <style type="text/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;
      }
    </style>
    <script>
      (function(exports) {
        "use strict";

        // This example requires the Geometry library. Include the libraries=geometry
        // parameter when you first load the API. For example:
        // <script src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&libraries=geometry">
        function initMap() {
          var map = new google.maps.Map(document.getElementById("map"), {
            center: {
              lat: 24.886,
              lng: -70.269
            },
            zoom: 5
          });
          var triangleCoords = [
            {
              lat: 25.774,
              lng: -80.19
            },
            {
              lat: 18.466,
              lng: -66.118
            },
            {
              lat: 32.321,
              lng: -64.757
            }
          ];
          var bermudaTriangle = new google.maps.Polygon({
            paths: triangleCoords
          });
          google.maps.event.addListener(map, "click", function(e) {
            var resultColor = google.maps.geometry.poly.containsLocation(
              e.latLng,
              bermudaTriangle
            )
              ? "blue"
              : "red";
            var resultPath = google.maps.geometry.poly.containsLocation(
              e.latLng,
              bermudaTriangle
            ) // A triangle.
              ? "m 0 -1 l 1 2 -2 0 z"
              : google.maps.SymbolPath.CIRCLE;
            new google.maps.Marker({
              position: e.latLng,
              map: map,
              icon: {
                path: resultPath,
                fillColor: resultColor,
                fillOpacity: 0.2,
                strokeColor: "white",
                strokeWeight: 0.5,
                scale: 10
              }
            });
          });
        }

        exports.initMap = initMap;
      })((this.window = this.window || {}));
    </script>
  </head>
  <body>
    <div id="map"></div>
  </body>
</html>
(function(exports) { "use strict"; // This example requires the Geometry library. Include the libraries=geometry // parameter when you first load the API. For example: // <script src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&libraries=geometry"> function initMap() { var map = new google.maps.Map(document.getElementById("map"), { center: { lat: 24.886, lng: -70.269 }, zoom: 5 }); var triangleCoords = [ { lat: 25.774, lng: -80.19 }, { lat: 18.466, lng: -66.118 }, { lat: 32.321, lng: -64.757 } ]; var bermudaTriangle = new google.maps.Polygon({ paths: triangleCoords }); google.maps.event.addListener(map, "click", function(e) { var resultColor = google.maps.geometry.poly.containsLocation( e.latLng, bermudaTriangle ) ? "blue" : "red"; var resultPath = google.maps.geometry.poly.containsLocation( e.latLng, bermudaTriangle ) // A triangle. ? "m 0 -1 l 1 2 -2 0 z" : google.maps.SymbolPath.CIRCLE; new google.maps.Marker({ position: e.latLng, map: map, icon: { path: resultPath, fillColor: resultColor, fillOpacity: 0.2, strokeColor: "white", strokeWeight: 0.5, scale: 10 } }); }); } exports.initMap = initMap; })((this.window = this.window || {}));
/* 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; }
<!DOCTYPE html> <html> <head> <title>Polygon Contains Location</title> <script src="https://polyfill.io/v3/polyfill.min.js?features=default"></script> <script src="https://maps.googleapis.com/maps/api/js?key=&callback=initMap&libraries=geometry&v=weekly" defer ></script> <!-- jsFiddle will insert css and js --> </head> <body> <div id="map"></div> </body> </html>