gtk_container_add (GTK_CONTAINER (w), GTK_WIDGET (canvas));
gtk_scrolled_window_set_policy(GTK_SCROLLED_WINDOW (w), GTK_POLICY_AUTOMATIC, GTK_POLICY_AUTOMATIC);
gtk_widget_set_events (GTK_WIDGET (canvas), GDK_EXPOSURE_MASK | GDK_POINTER_MOTION_MASK | GDK_BUTTON_MOTION_MASK | GDK_BUTTON_PRESS_MASK | GDK_BUTTON_RELEASE_MASK | GDK_KEY_PRESS_MASK | GDK_ENTER_NOTIFY_MASK | GDK_LEAVE_NOTIFY_MASK);
gtk_container_add (GTK_CONTAINER (w), GTK_WIDGET (canvas));
gtk_scrolled_window_set_policy(GTK_SCROLLED_WINDOW (w), GTK_POLICY_AUTOMATIC, GTK_POLICY_AUTOMATIC);
gtk_widget_set_events (GTK_WIDGET (canvas), GDK_EXPOSURE_MASK | GDK_POINTER_MOTION_MASK | GDK_BUTTON_MOTION_MASK | GDK_BUTTON_PRESS_MASK | GDK_BUTTON_RELEASE_MASK | GDK_KEY_PRESS_MASK | GDK_ENTER_NOTIFY_MASK | GDK_LEAVE_NOTIFY_MASK);