如何在THREE.js中克隆直线对象的网格？

var geometry = new THREE.Geometry();
geometry.vertices.push(
  new THREE.Vector3( -10, 0, 0 ),
  new THREE.Vector3( 0, 10, 0 ),
  new THREE.Vector3( 10, 0, 0 )
);
var material = new THREE.LineBasicMaterial( { color: 0x0000ff } );
var line = new THREE.Line( geometry, material );
scene.add( line );

var clonedLine = line.clone();
clonedLine.material = line.material.clone();
scene.add( clonedLine );