private void Button_Click(object sender, RoutedEventArgs e)
        {
            // Restart plant
            if (plant != null && ChkDemoPlant.IsChecked.Value)
            {
                plant.Clear();
            }

            // Remove all comtrol points
            else if (this.points != null)
            {
                this.points.Clear();
                Draw();
            }
        }