next up previous 200
Next: Picture identifiers
Up: Control
Previous: Opening the Database


Device names

For applications linked with the GKS based AGI library the user should supply a valid GNS device name (SUN/57) which AGI converts into an internal name that locates the workstation structure in the database. For devices that have more than one plotting plane, it is desirable that AGI treat pictures plotted on the different planes as being on the same device, so that plots on the overlay plane can be lined up with plots below them. Database entries for pictures on these different planes, which are different devices in GKS and SGS, will therefore appear in the same AGI workstation structure.

The AGP library is based on native-PGPLOT style device names of the form <devname>/<devtype>. The graphics device to be used is selected by the <devtype> component. The <devname> component before the / will be some form of name used by the device driver (typically a physical device on the system or an output file name) but is often omitted as most drivers contain a sensible default value. For example a graphics device of just /gwm will open a Starlink GWM X11 window with a default window name of xwindows while a complete specification of mywindow/gwm will open a GWM window with the name mywindow.

For native-PGPLOT based applications to co-exist with GKS-based ones it is important that users can continue to supply ``old_style'' GKS device names where these have a sensible translation. Where there IS such a translation the AGI database records must also be made to match. Logic has been incorporated into the AGP library to perform this name translation process. Also in AGP typing a single ? for the device name will list all the possible translations. At the time of writing this document these were:

gif_l     (/GIF)           GIF-format file, landscape
gif_p     (/VGIF)          GIF-format file, portrait
hpgl_l    (/HPGL)          Hewlett-Packard HP-GL plotters, landscape
hpgl_p    (/VHPGL)         Hewlett-Packard HP-GL plotters, portrait
hpgl2     (/HPGL2)         Hewlett-Packard graphics language
xterm     (/XTERM)         Tektronix terminal emulator
wd_l      (/WD)            X Window dump file, landscape
wd_p      (/VWD)           X Window dump file, portrait
xserve    (/XSERVE)        PGPLOT X window server
tek_4010  (/TEK4010)       Tektronix 4006-4010 storage-tube terminal
tek_4107  (/TEK4100)       Tektronix 4100-series terminals
ps_p      (/VPS)           Postscript printers, monochrome, portrait
ps_l      (/PS)            Postscript printers, monochrome, landscape
epsf_p    (/VPS)           Encapsulated postscript, portrait
epsf_l    (/PS)            Encapsulated postscript, landscape
pscol_p   (/VCPS)          PostScript printers, color, portrait
pscol_l   (/CPS)           PostScript printers, color, landscape
epsfcol_p (/VCPS)          Colour encapsulated postscript, portrait
epsfcol_l (/CPS)           Colour encapsulated postscript, landscape
xwindows  (xwindows/GWM)   Starlink GWM xwindow
x2windows (xwindows2/GWM)  Starlink GWM xwindow
x3windows (xwindows3/GWM)  Starlink GWM xwindow
x4windows (xwindows4/GWM)  Starlink GWM xwindow

As an example of the overall effect native-PGPLOT graphics specifications of xwindows/gwm, /gwm or xwindows are all valid and equivalent in the AGP version of the AGI library. They will select a GWM window with name xwindows which will have AGI database records identical to those created by the AGI library routines for the graphics device with the GNS name of xwindows.

The user will still see some slight differences from previous GKS behaviour when using GKS style device names via this scheme. For example:



next up previous 200
Next: Picture identifiers
Up: Control
Previous: Opening the Database

AGI --- Applications Graphics Interface Library
Starlink User Note 48
Nicholas Eaton
Brian McIlwrath
30 January 2002
E-mail:ussc@star.rl.ac.uk

Copyright © 2009 Science and Technology Facilities Council