code: function (tilePoint) {
  		return L.Util.template(this._url, L.extend({
  			s: this._getSubdomain(tilePoint),
  			z: tilePoint.z,
  			x: tilePoint.x,
  			y: tilePoint.y
  		}, this.options));
  	}
docs: image-specific code (override to implement e.g. Canvas or SVG tile layer)