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.

TypeScript

// 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(): void {
  const map = new google.maps.Map(
    document.getElementById("map") as HTMLElement,
    {
      center: { lat: 24.886, lng: -70.269 },
      zoom: 5,
    }
  );

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

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

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

    const 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,
      icon: {
        path: resultPath,
        fillColor: resultColor,
        fillOpacity: 0.2,
        strokeColor: "white",
        strokeWeight: 0.5,
        scale: 10,
      },
    });
  });
}
index.ts

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() {
  const map = new google.maps.Map(document.getElementById("map"), {
    center: { lat: 24.886, lng: -70.269 },
    zoom: 5,
  });
  const triangleCoords = [
    { lat: 25.774, lng: -80.19 },
    { lat: 18.466, lng: -66.118 },
    { lat: 32.321, lng: -64.757 },
  ];
  const bermudaTriangle = new google.maps.Polygon({ paths: triangleCoords });
  google.maps.event.addListener(map, "click", (e) => {
    const resultColor = google.maps.geometry.poly.containsLocation(
      e.latLng,
      bermudaTriangle
    )
      ? "blue"
      : "red";
    const 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,
      icon: {
        path: resultPath,
        fillColor: resultColor,
        fillOpacity: 0.2,
        strokeColor: "white",
        strokeWeight: 0.5,
        scale: 10,
      },
    });
  });
}

index.js

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.css

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="./index.js"></script>
  </head>
  <body>
    <div id="map"></div>
  </body>
</html>
sample.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>
      // 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() {
        const map = new google.maps.Map(document.getElementById("map"), {
          center: { lat: 24.886, lng: -70.269 },
          zoom: 5,
        });
        const triangleCoords = [
          { lat: 25.774, lng: -80.19 },
          { lat: 18.466, lng: -66.118 },
          { lat: 32.321, lng: -64.757 },
        ];
        const bermudaTriangle = new google.maps.Polygon({
          paths: triangleCoords,
        });
        google.maps.event.addListener(map, "click", (e) => {
          const resultColor = google.maps.geometry.poly.containsLocation(
            e.latLng,
            bermudaTriangle
          )
            ? "blue"
            : "red";
          const 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,
            icon: {
              path: resultPath,
              fillColor: resultColor,
              fillOpacity: 0.2,
              strokeColor: "white",
              strokeWeight: 0.5,
              scale: 10,
            },
          });
        });
      }
    </script>
  </head>
  <body>
    <div id="map"></div>
  </body>
</html>

inline.html
// 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=AIzaSyBIwzALxUPNbatRBj3Xi1Uhp0fFzwWNBkE&libraries=geometry"> function initMap() { const map = new google.maps.Map(document.getElementById("map"), { center: { lat: 24.886, lng: -70.269 }, zoom: 5, }); const triangleCoords = [ { lat: 25.774, lng: -80.19 }, { lat: 18.466, lng: -66.118 }, { lat: 32.321, lng: -64.757 }, ]; const bermudaTriangle = new google.maps.Polygon({ paths: triangleCoords }); google.maps.event.addListener(map, "click", (e) => { const resultColor = google.maps.geometry.poly.containsLocation( e.latLng, bermudaTriangle ) ? "blue" : "red"; const 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, icon: { path: resultPath, fillColor: resultColor, fillOpacity: 0.2, strokeColor: "white", strokeWeight: 0.5, scale: 10, }, }); }); }
/* 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=AIzaSyBIwzALxUPNbatRBj3Xi1Uhp0fFzwWNBkE&callback=initMap&libraries=geometry&v=weekly" defer ></script> <!-- jsFiddle will insert css and js --> </head> <body> <div id="map"></div> </body> </html>

Create a starter application from sample

A skeleton starter application using TypeScript, Webpack, and Babel can be generated from this sample using one of the methods below.

Run Locally

Node.js is required to run this sample locally. Follow these instructions to install Node.js and NPM. 

npx @googlemaps/js-samples init poly-containsLocation DESTINATION_FOLDER

Run in Google Cloud Shell

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Run in Cloud Shell