Simulation»Camera»Pivot (Ctrl+P) (Ctrl+Shift+P)
The Camera Pivot function sets the center of rotation for the camera to a specific vertex of an object (Ctrl+P) or the center of the currently selected objects (Ctrl+Shift+P). The pivot center is the point in space at which the camera will aim as it is rotated. If no object is selected, then the camera will rotate about the center of the world coordinate system (i.e., the center of the three grids).
To set the camera pivot to the center of selected objects using the menu, the Shift key must be pressed while selecting the menu.
Note that setting the camera pivot this way is only available with mouse scheme that do not have another mean of setting the pivot point.