@Override
    public void cloneFields( Cloner cloner, Object original ) {
        super.cloneFields(cloner, original);
        this.terrain = cloner.clone(terrain);
    }
Called internally by com.jme3.util.clone.Cloner.  Do not call directly.
jme3-terrain/src/main/java/com/jme3/terrain/geomipmap/NormalRecalcControl.java