threejs 物体重置锚点到物体中心

/**
 * 锚点重置到中心
 * @param {Object3D} mesh 
 */
function reAnchorCenter(mesh) {
  const geometry = mesh.geometry
  const position = mesh.position
  geometry.computeBoundingBox()
  const center = new THREE.Vector3();
  geometry.boundingBox.getCenter(center);
  const m = new THREE.Matrix4();
  m.set(1, 0, 0, center.x-position.x,
    0, 1, 0, center.y - position.y,
    0, 0, 1, center.z - position.z,
    0, 0, 0, 1)
  geometry.center();

  mesh.position.applyMatrix4(m)
}

该方法可以用于因为通过曲线，点阵生成物体，如管线，车削物体后锚点被设置在原点处，需要将锚点设置到物体中间时使用