A "world rectangle" is defined as the minimum size rectangle enclosing all objects including background pictures and text objects. The view window can be made to automatically fit the display by giving the Fit Window menu command from the View Menu. This function is also embedded in the toolstrip by selecting the Fit to Window tool button.
When the window is zoomed in or out, the size of Nodes and Text may remain fixed relative to the screen or may be scaled proportionally depending on whether the "Real-World size" or "Display size" option is chosen as the display attribute. By default the nodes are symbols of fixed screen size representing the centre point of an object or the junction of links.