/Leaflet.functionaltilelayer

Leaflet tile layer with functionally defined URL and support for promises.

Primary LanguageHTMLMIT LicenseMIT

Leaflet.functionaltilelayer

For use with Leaflet 1.0.1.

Leaflet tile layer with functionally defined URL and support for promises.

A typical use case is fetching tiles asynchronously, with an ajax request or IndexedDB query.

Usage

Use it like any other tile layer, but instead of providing a urlTemplate as the first argument, provide a function. The function should return either the tile URL as a string, or a promise which resolves to a string.

var funcLayer = new L.TileLayer.Functional(function (view) {
      var url = 'http://{s}.tile.osm.org/{z}/{x}/{y}.png'
        .replace('{z}', view.zoom)
        .replace('{y}', view.tile.row)
        .replace('{x}', view.tile.column)
        .replace('{s}', view.subdomain);

    return url;
});

The function is given a view object with the following properties:

view = {
  bbox,
  width,
  height,
  zoom,
  tile: {
    row,
    column
  },
  subdomain
};

For an example of the code above, see the [basic example] (example/basic.html).

For an example of using promises, see the [promise example] (example/promise.html).

Thanks

Thanks to @ryanttb and jQuery Geo's service objects, which were the inspiration for this plugin.

License

Leaflet.functionaltilelayer is free software, and may be redistributed under the MIT-LICENSE.