When the window is in zoom mode, you can draw a box around the area of the vis window that you want drawn larger. Press the left mouse button and move the mouse to sweep out a box that will define the area to be zoomed. Release the mouse button when the zoom box covers the desired area. If you start zooming and decide against it before releasing the left mouse button, clicking one of the other mouse buttons cancels the zoom operation. Changes to the view can be undone by selecting the Undo view option from the popup menu's View menu. Sometimes the zoom controls can change based on the interactor settings, which are described further on in Interactor settings.