Three.js如何获得一个对象相对于另一个对象的旋转？

var matrix1 = new THREE.Matrix4();
matrix1.copy(object1.getWorldMatrix());

var matrix2 = new THREE.Matrix4();
matrix2.copy(object2.getWorldMatrix());

var matrix2Inverse = new THREE.Matrix4();
matrix2Inverse.getInverse(matrix2);

var relativeMatrix = new THREE.Matrix4();
relativeMatrix.multiplyMatrices(matrix1, matrix2Inverse);

var relativeRotation = new THREE.Euler();
var relativeScale = new THREE.Vector3();
var relativeTranslation = new THREE.Vector3();

relativeMatrix.decompose(relativeTranslation, relativeRotation, relativeScale);

console.log("Object 1 relative rotation to Object 2: ", relativeRotation);