After invoking the command d.display, the DISPLAY MAIN MENU appears on the monitor. Options in this and subsequent d.display menus are selected through use of the pointing device (mouse). When the mouse cursor is over the desired menu selection, the user simply presses any button on the mouse.
d.display is a macro that allows the user to
access a wide range of GRASS display functions in a
menu-driven and highly interactive environment. Most of
the functions accessible through d.display can
also be run independently of one another by running the
GRASS display (d.) commands listed in the SEE ALSO
section, below. However, in many cases, these other
d. commands give the user greater flexibility and
make available more options than are available through the
d.display menus. For example, the
d.display label file option runs the
d.label command
using defaults. Users running d.label directly
from the command line have the choice of stipulating
specific label background and text colors, as well as text
sizes and font types. Users running the label
file option through d.display cannot specify
these options; instead, default values are used (see
d.label for default values
used).
The d.display tool is best learned by playing with its options.
Refer to the individual d. and other commands in the SEE ALSO section
for a detailed examination of these functions.
The main menu also offers the user the option of hiding the main menu
for ten seconds (hide menu for 10 seconds).
The d.display command must be run in conjunction
with a program which converts the GRASS graphics commands
generated by d.display to the graphics commands
that the current device understands. This device will
almost always be a graphics monitor. On most systems the
user is required to start up this other program separately
from (and prior to) d.display. In such cases, a
locally-defined program, usually "monitor", is used (see
your GRASS manager). (For example, on MASSCOMP machines,
the d.mon program
must be running in the foreground on the graphics monitor.
On SUN machines, the
d.mon program can be started
from any terminal and run in the background.)
d.display sends program output to the current
graphics frame (set, by default, to the full graphics
screen unless modified by the user). You can use
d.frame to create and
choose a smaller display frame on the graphics monitor for
use by d.display.
See the GRASS macro 3d.view.sh stored under
$GISBASE/scripts for an example of how you can create a
d.display-like macro using a shell script.
Last changed: $Date$
NOTES
The user can also modify the current region settings from
the DISPLAY MAIN MENU. Using the mouse, the user can
choose to zoom in on a portion of the
displayed raster map layer to create a smaller geographic
region. Once the user has defined the corners of this area
using the mouse, the smaller area is enlarged and replotted
on the screen. The user can similarly choose to
zoom out. In this case, the user uses the
mouse to encompass that portion of the reduced map that the
user wishes to make the current geographic region and
display in the center of the screen. The larger map is then
replotted and displayed. Finally, the user can enter
geographic coordinates for the region's corners from the
keyboard using the GRASS command
g.region. This is
done by selecting the type coordinates
option.
SEE ALSO
See 3d.view.sh
or slide.show.sh
under $GISBASE/scripts
for examples of d.display-like macros.
d.3d
d.colormode
d.colors
d.frame
d.label
d.legend
d.measure
d.mon
d.rast
d.scale
d.sites
d.vect
d.zoom
g.region
d.menu
v.digit
AUTHOR
James Westervelt, U.S. Army Construction Engineering
Research Laboratory