Sun/IRAF Site Manager's Guide

Sun/IRAF Site Manager's Guide

4.2. Vector graphics capabilities

The standard graphics terminal emulator for Sun/IRAF under SunView is gterm, which emulates a conventional dual plane text/graphics terminal. This software terminal is driven via an ASCII datastream like a conventional hard terminal (except that the effective baud rate is much higher). The text window behaves like the Sun console and the graphics window behaves like a Tektronix 4012, plus some IRAF oriented extensions. Since gterm emulates standard text and graphics devices non-IRAF programs can easily be run as well as IRAF programs.

Configuring IRAF to use gterm is very simple. The following command does the job. This is normally executed by the or file at login time.

 cl> stty gterm
A number of function keys are recognized by gterm which one should be aware of. Some of these are built into gterm itself, others are defined in the default .ttyswrc file.

Toggle between fullscreen graphics window and normal graphics window.
Clear (if in graphics mode) or enable (if in text mode) output to the graphics plane. Used to manually put the terminal into 4012 emulation mode.
Clear (if in text mode) or enable (if in graphics mode) the text plane. Closing the graphics plane will also enable the text plane.
Set text window size to 24 lines by 80 columns.
Set text window size to 34 lines by 80 columns.
Set text window size to 40 lines by 80 columns.
Set text window size to 54 lines by 80 columns. Tallest possible text window using standard font.

The text window may also be manually resized using the mouse but the function keys are most convenient for rapid changes to the window height. The IRAF software will automatically sense that the window size has changed whenever a screen oriented program is run. The current window size can be printed with stty show, or updated with stty resize.

There is a frame menu which may be used to access a number of useful functions, e.g., logging of all output to the terminal, or bitmap hardcopies of the text or graphics windows or the full screen. Control over the terminal setup is provided by a setup panel.

Note that the graphics window may also be resized and moved about on the screen. A number of predefined standard window sizes are provided via the gterm setup panel, ranging from pretty small to the full screen. The graphics window may also be interactively adjusted with the mouse to some arbitrary size, but the advantage of the predefined window sizes is that they all have the same standard aspect ratio and size in characters (35x80). Multiple IRAF sessions running in multiple gterm windows are possible; using different colors makes it easier to remember which window is which.

Aside from the dynamic nature of windows in the SunView environment, operation of IRAF from a gterm window is straightforward and should present no problems for someone already familiar with the use of IRAF on a conventional graphics terminal. Further information is given in the gterm manual page, gterm(l) (a UNIX level manpage).