Object3D src;
src.build();
src.strip();
Object3D obj = src.cloneObject(); // will throw a NullPointerException
Should this behavior be legal?
No, that's not supposed to work, but it should actually throw a proper exception and not a null pointer. I'll look into it. However, if you want to strip objects that are sharing meshes, do a object.getMesh().setLocked(true); before. That should do the trick.