[Solved]This project can not be used with the BufferGeoMetry of the FBX model ?

[gzlock]

All examples of examples.html can see the results, but when use with the fbx model can not see the result without any error messages.
So I insert the console.log function to test, found the following program will stop at step 2.
What to do next?

  //es6 js style
  //defined scene camera renderer blahblahblah
  const manager = new THREE.LoadingManager();
  const loader = new THREE.FBXLoader(manager);
  loader.load('https://threejs.org/examples/models/fbx/xsi_man_skinning.fbx', fbx => {
    window.FBX = fbx;
    /*
      Found the fbx.children[0].children[1].isMesh is true and had geometry data(Type of BufferGeometry)
    */
    let start_time = new Date().getTime();
    let cubeGeo = new THREE.CubeGeometry(5, 5, 1);

    console.log('step 1');
    let cube_bsp = new ThreeBSP(cubeGeo);

    console.log('step 2');
    let car_bsp = new ThreeBSP(fbx.children[0].children[1].geometry);

    console.log('step 3');
    let subtract_bsp = car_bsp.intersect(cube_bsp);

    console.log('step 4');
    let result = subtract_bsp.toMesh(new THREE.MeshLambertMaterial({
      shading: THREE.SmoothShading
    }));

    console.log('step 5');
    result.geometry.computeVertexNormals();
    scene.add(result);
    console.log('used time: ' + ((new Date()).getTime() - start_time) + 'ms');
  });

[gzlock]

Use new ThreeBSP(new GeoMetry().fromBufferGeoMetry(bufferGeoMetry))

[thibka]

var myMesh;
gltf.scene.traverse(function (child) {
    if (child.isMesh) {
        myMesh = child;
    }
});
const sBSP = new ThreeBSP(new THREE.Geometry().fromBufferGeometry(myMesh.geometry));