public void updateUndoRedoControls() {
UndoManager undoManager = renderPanel.getUndoManager();
JButton redoButton=buttons.get("redo");
JButton undoButton=buttons.get("undo");
if (undoManager.canRedo()) {
redoButton.setEnabled(true);
redoMenu.setEnabled(true);
redoButton.setToolTipText(GT.get("Redo")+": "+undoManager.getRedoPresentationName());
} else {
redoButton.setEnabled(false);