scale optimization :)

src/ui/view/GUI.java

@@ -160,7 +160,7 @@ public class GUI implements CategoryListener {
 			@Override
 			public void stateChanged(ChangeEvent e) {
 				controller.setScale(slider.getValue());
-				updateCategories(model.getCategories());
+				tree.setRowHeight(model.getScale());
 				canvas.objectSelectionHighlighting();
 				canvas.repaint();
 			}