final ScalingControl scaler = new CrossoverScalingControl();
JButton plus = new JButton("+");
plus.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
scaler.scale(vv1, 1.1f, vv1.getCenter());
}
});
JButton minus = new JButton("-");
minus.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {