A number of shortcut keys are available to carry out common viewer tasks. These can be carried out by clicking in the viewer window and pressing the associated key.
Key  | Action  | 
|---|---|
space  | Toggles between picking and viewing mode.  | 
arrow keys  | Rotates about horizontal and vertical axes.  | 
Ctrl + up/down arrow keys  | Rotates about an axis normal to the screen.  | 
Shift + arrow keys  | Moves the light source.  | 
1  | Switches to one viewport.  | 
2  | Switches to two viewports.  | 
3  | Switches to three viewports.  | 
4  | Switches to four viewports.  | 
C  | Centers the graphic object in the viewer window.  | 
N  | Toggles the projection between orthographic and perspective.  | 
R  | Resets the view to the initial orientation.  | 
S  | Toggles the level of detail between auto, off, and on.  | 
U  | Undoes transformation.  | 
Shift+U  | Redoes transformation.  | 
X  | Sets view from +X axis.  | 
Shift+X  | Sets view from -X axis.  | 
Y  | Sets view from +Y axis.  | 
Shift+Y  | Sets view from -Y axis.  | 
Z  | Sets view from +Z axis.  | 
Shift+Z  | Sets view from -Z axis.  | 
The information in this table is accessible by clicking the Show Help Dialog 
  toolbar icon in the 3D Viewer toolbar.