@Override
    public void depthFirstTraversal(SceneGraphVisitor visitor, DFSMode mode) {
        if (mode == DFSMode.POST_ORDER) {
            for (Spatial child : children.getArray()) {
                child.depthFirstTraversal(visitor, mode);
            }
            visitor.visit(this);
        } else { //pre order
            visitor.visit(this);
            for (Spatial child : children.getArray()) {
                child.depthFirstTraversal(visitor, mode);
            }
        }
    }
Called internally by com.jme3.util.clone.Cloner.  Do not call directly.
jme3-core/src/main/java/com/jme3/scene/Node.java