Custom Symbols (Polyline)

This example adds a custom symbol to a polyline.

Read the documentation.

TypeScript

// This example adds three custom symbols to a polyline.

function initMap(): void {
  const map = new google.maps.Map(
    document.getElementById("map") as HTMLElement,
    {
      zoom: 6,
      center: { lat: 20.291, lng: 153.027 },
      mapTypeId: "terrain",
    }
  );

  // Define the custom symbols. All symbols are defined via SVG path notation.
  // They have varying stroke color, fill color, stroke weight,
  // opacity and rotation properties.
  const symbolOne = {
    path: "M -2,0 0,-2 2,0 0,2 z",
    strokeColor: "#F00",
    fillColor: "#F00",
    fillOpacity: 1,
  };

  const symbolTwo = {
    path: "M -1,0 A 1,1 0 0 0 -3,0 1,1 0 0 0 -1,0M 1,0 A 1,1 0 0 0 3,0 1,1 0 0 0 1,0M -3,3 Q 0,5 3,3",
    strokeColor: "#00F",
    rotation: 45,
  };

  const symbolThree = {
    path: "M -2,-2 2,2 M 2,-2 -2,2",
    strokeColor: "#292",
    strokeWeight: 4,
  };

  // Create the polyline and add the symbols via the 'icons' property.
  const line = new google.maps.Polyline({
    path: [
      { lat: 22.291, lng: 153.027 },
      { lat: 18.291, lng: 153.027 },
    ],
    icons: [
      {
        icon: symbolOne,
        offset: "0%",
      },
      {
        icon: symbolTwo,
        offset: "50%",
      },
      {
        icon: symbolThree,
        offset: "100%",
      },
    ],
    map: map,
  });
}

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

JavaScript

// This example adds three custom symbols to a polyline.
function initMap() {
  const map = new google.maps.Map(document.getElementById("map"), {
    zoom: 6,
    center: { lat: 20.291, lng: 153.027 },
    mapTypeId: "terrain",
  });
  // Define the custom symbols. All symbols are defined via SVG path notation.
  // They have varying stroke color, fill color, stroke weight,
  // opacity and rotation properties.
  const symbolOne = {
    path: "M -2,0 0,-2 2,0 0,2 z",
    strokeColor: "#F00",
    fillColor: "#F00",
    fillOpacity: 1,
  };
  const symbolTwo = {
    path: "M -1,0 A 1,1 0 0 0 -3,0 1,1 0 0 0 -1,0M 1,0 A 1,1 0 0 0 3,0 1,1 0 0 0 1,0M -3,3 Q 0,5 3,3",
    strokeColor: "#00F",
    rotation: 45,
  };
  const symbolThree = {
    path: "M -2,-2 2,2 M 2,-2 -2,2",
    strokeColor: "#292",
    strokeWeight: 4,
  };
  // Create the polyline and add the symbols via the 'icons' property.
  const line = new google.maps.Polyline({
    path: [
      { lat: 22.291, lng: 153.027 },
      { lat: 18.291, lng: 153.027 },
    ],
    icons: [
      {
        icon: symbolOne,
        offset: "0%",
      },
      {
        icon: symbolTwo,
        offset: "50%",
      },
      {
        icon: symbolThree,
        offset: "100%",
      },
    ],
    map: map,
  });
}

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>Custom Symbols (Polyline)</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.
      See https://developers.google.com/maps/documentation/javascript/load-maps-js-api
      for more information.
      -->
    <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-overlay-symbol-custom 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