How to calculate the conversion matrix of two meshes

Questions
9

@srzerbetto
Thanks for your help:

But in my case, the loaded stl mesh always show the AABB boundingBox instead of OBB

    const directions = mesh.getBoundingInfo().boundingBox.directions;
    console.log(directions);

1. Array(3)
  1. 0: Vector3 {_isDirty: true, _x: 1, _y: 0, _z: 0}
  2. 1: Vector3 {_isDirty: true, _x: 0, _y: 1, _z: 0}
  3. 2: Vector3 {_isDirty: true, _x: 0, _y: 0, _z: 1}
  4. length: 3
  5. [[Prototype]]: Array(0)