@Override
    public Spatial clone() {
        return clone(true);
    }
@return A clone of this Spatial, the scene graph in its entirety
is cloned and can be altered independently of the original scene graph.

Note that meshes of geometries are not cloned explicitly, they
are shared if static, or specially cloned if animated.

@see Mesh#cloneForAnim()
jme3-core/src/main/java/com/jme3/scene/Spatial.java