Dashed Line Symbols (Polyline)

This example converts a polyline to a dashed line, by setting the opacity of the polyline to 0, and drawing an opaque symbol at a regular interval on the polyline.

Read the documentation.

TypeScript

// This example converts a polyline to a dashed line, by
// setting the opacity of the polyline to 0, and drawing an opaque symbol
// at a regular interval on the 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 a symbol using SVG path notation, with an opacity of 1.
  const lineSymbol = {
    path: "M 0,-1 0,1",
    strokeOpacity: 1,
    scale: 4,
  };

  // Create the polyline, passing the symbol in the 'icons' property.
  // Give the line an opacity of 0.
  // Repeat the symbol at intervals of 20 pixels to create the dashed effect.
  const line = new google.maps.Polyline({
    path: [
      { lat: 22.291, lng: 153.027 },
      { lat: 18.291, lng: 153.027 },
    ],
    strokeOpacity: 0,
    icons: [
      {
        icon: lineSymbol,
        offset: "0",
        repeat: "20px",
      },
    ],
    map: map,
  });
}

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

JavaScript

// This example converts a polyline to a dashed line, by
// setting the opacity of the polyline to 0, and drawing an opaque symbol
// at a regular interval on the polyline.
function initMap() {
  const map = new google.maps.Map(document.getElementById("map"), {
    zoom: 6,
    center: { lat: 20.291, lng: 153.027 },
    mapTypeId: "terrain",
  });
  // Define a symbol using SVG path notation, with an opacity of 1.
  const lineSymbol = {
    path: "M 0,-1 0,1",
    strokeOpacity: 1,
    scale: 4,
  };
  // Create the polyline, passing the symbol in the 'icons' property.
  // Give the line an opacity of 0.
  // Repeat the symbol at intervals of 20 pixels to create the dashed effect.
  const line = new google.maps.Polyline({
    path: [
      { lat: 22.291, lng: 153.027 },
      { lat: 18.291, lng: 153.027 },
    ],
    strokeOpacity: 0,
    icons: [
      {
        icon: lineSymbol,
        offset: "0",
        repeat: "20px",
      },
    ],
    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>Dashed Line 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-dashed 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