huginn/app/assets/javascripts/map_marker.js

window.map_marker = function (map, options) {
  let marker;
  if (options == null) {
    options = {};
  }
  const pos = new google.maps.LatLng(options.lat, options.lng);

  if (options.radius > 0) {
    marker = new google.maps.Circle({
      map,
      strokeColor: "#FF0000",
      strokeOpacity: 0.8,
      strokeWeight: 2,
      fillColor: "#FF0000",
      fillOpacity: 0.35,
      center: pos,
      radius: options.radius,
    });
    return marker;
  } else if (options.course) {
    const p1 = new LatLon(pos.lat(), pos.lng());
    const speed = options.speed != null ? options.speed : 1;
    const p2 = p1.destinationPoint(options.course, Math.max(0.2, speed) * 0.1);

    const lineCoordinates = [pos, new google.maps.LatLng(p2.lat(), p2.lon())];

    const lineSymbol = { path: google.maps.SymbolPath.FORWARD_CLOSED_ARROW };

    const arrow = new google.maps.Polyline({
      map,
      path: lineCoordinates,
      icons: [
        {
          icon: lineSymbol,
          offset: "100%",
        },
      ],
    });
    return arrow;
  } else {
    marker = new google.maps.Marker({
      map,
      position: pos,
      title: "Recorded Location",
    });
    return marker;
  }
};