CIGAL Reference Manual, Chapter 4 (cursor):
usage: cursor = value
CURSOR is an internally defined integer variable controlling options related to how the cursor is moved and displayed. The value of the CURSOR parameter can be changed at any time and remains set until it is explicitly modified again.
The low 3 bits of the CURSOR flag specify which pointing devices are present. Currently CIGAL recognizes a Microsoft type “mouse” and/or a digitizing tablet. (For details on how to configure your digitizing tablet see [TABLETS] or [TABLET].) In addition to the cursor pointers specified in the CURSOR flag, the cursor can also be moved at any time by using the arrow keys on the terminal keyboard (see [KEYBOARD]). You can specify as many different pointers as your hardware supports. CIGAL continuously poll each pointer and automatically use whichever is being moved at the time. The higher-order bits in the CURSOR flag specify how the coordinates returned by the cursor pointer are transformed and displayed. The meanings of the CURSOR settings are summarized below.
Combine levels by adding values (values shown are octal): Value 1 MOUSE_OUT Use mouse cursor display 2 MOUSE_IN A mouse is available for input 4 TABLET A digitizing tablet is present 10o IPROC Show cursor on image processor display 20o TERM Draw cursor on terminal display (if no mouse) 40o NOCLIP Don't restrict cursor to cursor window 100o NOCURSOR Don't display any cursor 200o NODRAWOFF Don't turn cursor display off while drawing vectors 400o MAP_INPUT Map cursor window (^^5) values to fill data window (^^6) 1000o MAP_OUTPUT Map data window values (^^6) to fill display window (^^2) 2000o NOMODE_SET Don't change cursor windows when changing video mode (ignored if MOUSE_IN flag is not set) 4000o HORIZ_LINE Draw horizontal line cursor 10000o VERT_LINE Draw vertical line cursor (Note: Crosshair is 14000o) 20000o BOX Draw box cursor 40000o RUBBERBAND Draw "rubberband" cursor 100000o CURSOR_ON Cursor is currently being displayed (this bit will normally never appear set -- don't change this)
NOTE: When CIGAL starts up it automatically tests to see whether a “mouse” is present; if it is then CURSOR is set to 3. If you have a mouse, then the cursor windows (^^2 and ^^5) will normally be changed automatically when you change video modes, in order to adjust to changes in the mouse coordinates associated with different video modes. This can be suppressed by setting the NOMODE_SET flag.
See WINDOWS(1) for more information on the cursor, data, and display