Load tileset images from tilemap

Examples
1

It took me a few years to figure this out.

this.load.tilemapTiledJSON("map", "assets/tilemaps/maps/multi-tileset-v12.json");

this.load.once(
  "filecomplete-tilemapJSON-map",
  function (key, type, data) {
    this.load.setPath("/assets/tilemaps/maps/");

    for (var tileset of data.data.tilesets) {
      this.load.image(tileset.name, tileset.image);
    }
  },
  this
);

You can also add tilesets and layers directly from the map data:

var map = this.add.tilemap("map");

for (var tileset of map.tilesets) {
  map.addTilesetImage(tileset.name);
}

for (var layerData of map.layers) {
  map.createLayer(layerData.name, map.tilesets);
}