Select a view
A window view may be selected. If a view is selected a small black triangle
is shown in the top-left. To selected another view click in the new view.
Center a point in a view
To center a point in a view you only have to open the "Command" menu and
choose the command "center" or, more easily, use
the key "c" and click with the mouse in the point you want to center
the scene.
Zoom a view
To zoom is as easy as to center: open the "Command" menu and choose zoom
in/out or use the keys "i"/ "o" .