NAME

d.igraph - Graphics interface for GRASS on the Intergraph.
(Map Development Tool)

SYNOPSIS

d.igraph

DESCRIPTION

d.igraph is the GRASS interface to the GRASS graphics driver on the Intergraph workstations. GRASS can be run from an ascii terminal or from a window on the Intergraph workstation. There are some pitfalls to running GRASS from a window; these are discussed in the NOTES section below.

When d.igraph is run a pull-down menu will appear on the workstation screen and some information will be displayed on the ascii terminal. The pull-down menu, which works the same way other Intergraph pull down-menus work, will look like this: 

  _______________________
  |  GRASS Commands      |
  |  start/select        |
  |  stop                |
  |  GRASS Graphics      |
  |  resize/move         |
  |  virtual screens    >|
  |  colors             >|
  | EXIT                 |
  |______________________|
The menu is divided into two categories: GRASS Commands and GRASS Graphics. GRASS Commands in the pull-down menu have GRASS command-line equivalents. These command-line equivalents can be used without running d.igraph, although users may find the pull-down menu commands easier and faster to use. On the other hand, there are no command-line equivalents for the GRASS Graphics commands in the pull-down menu. These commands, which must be run from inside d.igraph, enable you to modify the size, placement, and number of colors, of the graphics window.

The first command under GRASS Commands is start/select; selecting this command with the mouse will start the graphics driver IGRAPH and then select it for output. This pull-down menu command is equivalent to typing the following commands at the GRASS command line:

d.mon start=IGRAPH
(start and select the IGRAPH graphics driver)
or
d.mon -s start=IGRAPH
(start but don't select the IGRAPH driver)
d.mon select=IGRAPH
(select the already started IGRAPH driver)
Using the start/select option saves the user from having to type the above command(s). After the graphics driver is started, the pull-down menu will disappear and the d.igraph program will exit, leaving the user at the GRASS prompt. When the second command (stop) under GRASS Commands is selected, the graphics driver IGRAPH will stop and the GRASS window will disappear. The equivalent GRASS command-line command is: d.mon stop=IGRAPH.

The second category (GRASS Graphics) in the pull-down menu contains three commands written for the GRASS graphics driver IGRAPH. These commands establish parameters for size, location, and number of colors the graphics driver will use to create a GRASS graphics window. Therefore, they should be run before starting the graphics driver with the start/select command. These parameters will not affect a GRASS window that has already been started, but they will be saved and used the next time the graphics driver is started.

The first command in the second category is resize/move. When the resize/move command is selected, the pull-down menu will disappear and a special Resize window, colored grey, will be created on the graphics monitor. The Resize window will be the exact size and at the same location as the GRASS graphics window would be if the graphics driver had been started. Use the resize and move icons on the Resize window to modify the window. When the desired size and position has been achieved, delete the Resize window. To do this, move the mouse to the left side of the icon strip at the top of the Resize window and click the mouse on the small box containing an X. Note that the window size is displayed on the ascii terminal in which the d.igraph program was started. Now, each time the graphics monitor is started, the window will be the same size and at the same location as the Resize window.

The second command is virtual screens. This command has a sub-menu with a listing of virtual screen numbers (from 0 to 3). Of the virtual screen numbers listed (0 to 3), only one or two of those numbers will be active and selectable from the sub-menu. The number of selectable virtual screen numbers will depend on the type of workstation and its virtual screen configuration. When the IGRAPH driver is started, it will create a GRASS window on the virtual screen whose number was picked by this command. Note that the current virtual screen number is displayed on the ascii terminal n which the d.igraph program was started.

The third graphics command is colors. This command has a sub-menu with a listing of the possible range of active colors the workstations will support (16 to 512). The number of active colors is determined by the number of planes the graphics processor supports (9 planes will give 512 active colors). We do not suggest running GRASS with fewer than 256 active colors.

Each workstation can be configured differently with regard to the number of virtual screens and the available number of colors. A certain amount of testing will have to been done to determine what works best with a particular workstation.

The last command is the EXIT command. This command is used to leave the d.igraph program.

USING THE GRAPHICS WINDOW

Once the GRASS graphics driver is started, a window will appear on the screen. The GRASS graphics window is mouse-activated. The mouse must be within the GRASS graphics window for the true GRASS colors to be displayed on the graphics window. The mouse doesn't have to be clicked inside the window; just moving the mouse within the window is enough to activate the window. While the mouse is outside the GRASS graphics window, the colors in the graphics window will be random.

NOTES

Obsolete for LINUX, of course!

When using the GRASS program d.colors or the interact selection in the d.display program, the mouse must be within the GRASS graphics window when toggling or highlighting categories. If the mouse is not within the graphics window, the colors will not represent the true category colors. Using the two programs mentioned above while running GRASS from an Intergraph window (ascii window) creates a problem; The mouse must be within the graphics window at all times for those programs to work properly, but the mouse also must be moved to the ascii window to activate the ascii window so that commands can be typed. This is not a problem when GRASS is run from an ascii terminal, because the mouse can be left within the GRASS graphics window at all times.

AUTHOR

Michael Higgins, U.S.Army Construction Engineering Research Laboratory

Last changed: $Date$