Export Leaflet Map as JPG in typescript angular 4

Question

I'm making an Angular4 app with leaflet maps and I need to export the current view of a map in one JPG image. Something like taking a screen shot but just the map with markers and polylines.

So, first I put markers and polylines in my leaflet map, and then I have to press a button that export the current view (including markers an polylines) in a JPG or PNG image and then ask me where to save the image.

Is there any way to do that? Some plugin that I could use?

Please help

Answer 1

Here is a rough implementation, substitute in your own relevant code.

The last function saveSvgAsPng() is from this library https://github.com/exupero/saveSvgAsPng, it allows you to save a <svg> element into a PNG or data url

function convertToPng() {
  const mapContainerRect = yourLeafletMapInstance.getContainer().getBoundingClientRect();
  const svg = document.createElementNS('http://www.w3.org/2000/svg', 'svg');
  const mapTiles = document.querySelectorAll('classe-of-map-tile-image');
  const markers = document.querySelectorAll('classe-of-marker');
  const polylines = document.querySelectorAll('polyline-element-class');

  svg.setAttribute('width', mapContainerRect.width;
  svg.setAttribute('height', mapContainerRect.height);

  mapTiles.forEach(tile => {
    const image = document.createElementNS('http://www.w3.org/2000/svg', 'image');
    const tileRect = tile.getBoundingClientRect();
    image.setAttribute('width', tileRect.width);
    image.setAttribute('height', tileRect.height);
    image.setAttribute('x', tileRect.left - mapContainerRect.left);
    image.setAttribute('y', tileRect.top - mapContainerRect.top);
    image.setAttribute('xlink:href', tile.src);
    svg.appendChild(image);
  });

  markers.forEach(marker => {
    const image = document.createElementNS('http://www.w3.org/2000/svg', 'image');
    const markerRect = marker.getBoundingClientRect();
    image.setAttribute('width', markerRect.width);
    image.setAttribute('height', markerRect.height);
    image.setAttribute('x', markerRect.left - mapContainerRect.left);
    image.setAttribute('y', markerRect.top - mapContainerRect.top);
    image.setAttribute('xlink:href', marker.src);
    svg.appendChild(image);
  });

  polylines.forEach(polyline => {
    const copy = polyline.cloneNode();
    svg.appendChild(copy);
  });


  saveSvgAsPng(svg, "map.png");
}