The Side View tool provides a convenient and intuitive way to zoom the view and to control global clipping. See also: clip, zoom, camera
Like other tools, this interface can be opened from the Tools menu (more...).
The auto clip checkboxes indicate whether the near and/or far planes should adjust automatically to avoid clipping the contents of the scene.
If the interactive response becomes slow with very large structures or other copious or large data, closing the Side View may help by reducing the rendering load.
Capping of clipped surfaces can be controlled with a preference setting and/or the surface cap command.