nction (gl, scene, camera) {
            stats = new Stats();
            stats.domElement.style.zIndex = 100;
            document.getElementById('map').appendChild(stats.domElement);

            var light = new THREE.DirectionalLight(0xffffff);
            light.position.set(0, -10, 10).normalize();
            scene.add(light);

            // const extent = new maptalks.Extent(120.41015625, 31.25037814985572, 120.421142578125, 31.259769987394264);
            // const material = new THREE.MeshBasicMate