  * custom  component
         *
         * you can customize your own components
         * */

        class RingEffect extends maptalks.BaseObject {
            constructor(coordinate, options, material, layer) {
                options = maptalks.Util.extend({}, OPTIONS, options, {
                    layer,
                    coordinate
                });
                super();
                //Initialize internal configuration
                // https://github.com/maptalks/maptalks.three/blob/1e4