NAME
d.graph - Program for generating and displaying simple graphics on the display monitor.
KEYWORDS
display,
cartography
SYNOPSIS
d.graph
d.graph --help
d.graph [-m] [input=name] [color=string] [--help] [--verbose] [--quiet] [--ui]
Flags:
- -m
- Coordinates are given in map units
- --help
- Print usage summary
- --verbose
- Verbose module output
- --quiet
- Quiet module output
- --ui
- Force launching GUI dialog
Parameters:
- input=name
- Name of file containing graphics commands, if not given reads from standard input
- color=string
- Color to draw with, either a standard GRASS color or R:G:B triplet
- Default: black
d.graph
draws graphics that are described either from standard input (default),
or within a file (if an
input file name is identified on the
command line). If graphics commands are entered from standard input,
a
CTRL-d is used to signal the end of input to
d.graph.
Coordinates are given either as a percentage of frame height and width
(default) or in geographic coordinates (with the
-m flag).
The program can be run interactively or non-interactively.
The user can run the program completely non-interactively
by specifying the name of a graphics file containing the
d.graph graphics commands. If run non-interactively the
d.graph command is saved to the display's dedraw history.
The user can also elect to run the program partially interactively,
by specifying any/all of the parameters except
the graphics file input=name parameter on the command line.
In this case, d.graph will expect the user to input d.graph
graphics commands from standard input (i.e., the keyboard) and
will (silently) prompt the user for these graphics commands.
Alternately, the user can simply type d.graph on the command line,
and be prompted for the values of all parameters. In this case, the user is presented with the standard
GRASS GUI interface.
The default coordinate system used is 0-100 percent of the active frame
in x and similarly 0-100 in y,
regardless of the graphics monitor display frame size and aspect.
The (0,0) location is the lower left corner of the active graphics
monitor display frame. All values may be floating point.
If the -m flag is given, geographic coordinates will be used instead.
The graphics language is simple, and uses the following commands:
- [
# |
move |
draw |
polygon |
polyline |
color |
text |
size |
symbol |
rotation |
icon |
width
]
- # comment
- A line of comment which is ignored in the processing.
- move xpos ypos
- The current location is updated to xpos ypos.
Unless the -m flag is used,
values are stated as a percent of the active display frame's
horizontal (xpos) and vertical (ypos) size,
and may be floating point values. Values are between 0-100.
Note. A space must separate xpos and ypos.
- draw xpos ypos
- A line is drawn in the current color from the current location to the new
location xpos ypos, which then becomes the current location.
Unless the -m flag is used,
values are stated as a percent of the active display frame's
horizontal (xpos) and vertical (ypos) size,
and may be floating point values. Values are between 0-100.
Note. A space must separate xpos and ypos.
- polygon
xpos ypos
xpos ypos
...
- The coordinates appearing beneath the word polygon,
one pair per line,
circumscribe a polygon that is to be filled with the current color.
- polyline
xpos ypos
xpos ypos
...
- The coordinates appearing beneath the word polyline,
one pair per line,
circumscribe a polygon that is not to be filled with color.
- color color
- Sets the current color to that stated; subsequent graphics will be drawn
in the stated color, until the current color is set to a different color.
Options are red,
orange,
yellow,
green,
blue,
indigo,
violet,
brown,
magenta,
gray,
white,
black,
an R:G:B triplet (separated by colons),
or the word "none" (draws in the default background color).
- text line-of-text
- The stated text is drawn at the current location using the current color,
and the new current location is then positioned at the end of the text string.
- size xper yper
- Subsequent text will be drawn such that the text is
xper percent of the graphics monitor display frame wide and
yper percent of the frame high. By default, the text size is set to
5 percent of the active frame's width and 5 percent of the frame's height.
If only one value is given, then that value will be used for both x and y
scaling.
Note. A space must separate xper and yper.
- symbol type size xper yper [line_color [fill_color]]
- A symbol is drawn at the given size on the display monitor. The
xper and yper options define the center of the icon and
are given as a percentage of the display frame (0,0 is lower left).
The symbol can be any of those stored in $GISBASE/etc/symbol/
(e.g. basic/circle) or stored in the user's mapset directory in the
form $MAPSET/symbol/type/name.
The colors may be either a standard color name, an R:G:B triplet,
or "none". If using an R:G:B triplet, each color value can range from 0-255.
If not specified the default line_color is black and the default
fill_color is grey.
- rotation angle
- Subsequent text and symbols will be drawn such that they are rotated
angle degrees counter-clockwise from east.
- icon type size x y
- Draws an icon of types o, x, or +
with specified size (in %) at location x,y.
Note: type o designates a square.
- width value
- Subsequent lines (including non-FreeType text) will be drawn with
the given pixel thickness.
The default value is 0.
For an example use of
d.graph, examine the contents of the
command file
grass_logo.txt
located in the
d.graph source code directory. It will draw the
CERL GRASS logo using the
d.graph graphing commands stored in the file.
Note that the coordinates in the
grass_logo.txt file were
taken directly off an image drawn by hand on graph paper.
A dynamic example can be found in the d.polar shell script.
echo "symbol basic/star 20 2264417 5413182 black red" | d.graph -m
d.frame -s full_screen
d.graph << EOF
color 80:80:120
polygon
0 49.75
0 50.25
100 50.25
100 49.75
polygon
49.85 0
50.15 0
50.15 100
49.85 100
EOF
d.graph remembers the last screen location (
xpos ypos) to which
the user moved, even after the user erases the display frame.
If the user runs
d.graph repeatedly, and wishes to start anew with
the default (xpos ypos) screen location, the user should
clear the
display frame between runs of
d.graph.
There are no automated ways of generating graphic images. It is anticipated
that GRASS user sites will write programs to convert output from a resident
graphics editor into GRASS
d.graph format.
(e.g. EPS ->
d.graph, perhaps with the help of a
pstoedit plugin)
d.font,
d.labels,
d.polar,
d.text,
d.where
James Westervelt, U.S. Army Construction Engineering Research Laboratory
SOURCE CODE
Available at:
d.graph source code
(history)
Latest change: Thursday Jan 26 14:10:26 2023 in commit: cdd84c130cea04b204479e2efdc75c742efc4843
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© 2003-2024
GRASS Development Team,
GRASS GIS 8.5.0dev Reference Manual