The intelligence of the command interpreter also ensures error-tolerant 
input. Input requests are backed up by appropriate default values. 
Efficient input means are 
- menus (especially for object-structured data acquisition and 
editing), 
- macro commands for frequently recurring operations, and 
- manual entry. 
The menu system in particular is a user-friendly entry method. The photo- 
grammetric operator or cartographic editor can concentrate on the task on 
hand without concerning himself with input commands or object structures. 
PHOCUS therefore contains a versatile menu system. It comprises: 
- The TABLET menu, an overlay that can be arranged freely on the 
tablet of the P1/P3 Planicomp or the PD digitizing subsystem 
(up to 4 overlays). 
- The Planicomp menu for defining the soft keys of the Planicomp 
P-Cursor (Fig. 5) or the foot switches, if available. 
- The DIGITIZER menu for defining the soft keys of the so-called 
D-Cursor of the PD digitizing subsystem. 
- The GRAPHICS menu, a menu line on a graphics screen. 
- The PANEL menu for defining the soft keys of an additional command 
panel (PHOCUS Panel). 
- The SOFT-KEY menu for defining the soft keys of an alphanumeric 
terminal (e.g. the system console). 
At system installation time, the user is provided with a large number of 
ready-made menus that facilitate general handling (calling application 
functions, parameter entry, help) and support special applications (e.g. 
measurement and editing functions). 
  
Travel keys 
  
  
  
  
  
Soft keys 
Z thumbwheel 
Cross-hairs 
  
  
  
Fig. 5: The P-Cursor - 
The main control element for the P1/P3 Planicomp Operator 
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