Ubuntu Manpage: d.colors - Allows the user to interactively change the color table of a raster map layer displayed on

NAME

       d.colors   -  Allows  the user to interactively change the color table of a raster map layer displayed on
       the graphics monitor.

KEYWORDS

       display, raster

SYNOPSIS

       d.colors
       d.colors help
       d.colors map=string  [--verbose]  [--quiet]

   Parameters:
       map=string
           Name of raster map

DESCRIPTION

A color table file associates specific colors with the categories of a raster map layer. The user can
change these map category color assignments (i.e., change the map's color table) interactively, by first
displaying the raster map to the graphics monitor and then running the program d.colors.

Any color changes made using d.colors will not immediately be shown on the graphics display; however, any
color changes saved will still alter the map's color table and will appear next time the raster map layer
is redisplayed (see d.colortable).

The user must first display the relevant raster map layer to the active frame on the graphics monitor
(e.g., using d.rast) before running d.colors. The user can then either enter the name of the raster map
layer whose color table is to be changed on the command line (e.g., by typing: d.colors map=soils), or
type d.colors without program arguments. If the user simply types d.colors without program arguments on
the command line, d.colors will ask the user to enter the name of an existing raster map layer using the
standard GRASS interface.

In either case, the user is then presented with the d.colors command menu, shown below. The d.colors
commands are listed beneath the Category Pointer Movement, Color Modification, Replotting Screen, and
Quitting sections below. Commands are invoked by typing in the single-key response shown to the left
below. (Longer descriptions of these commands appear to the right.) Results from invoking these commands
will be reflected in the Category and Category Number sections of the d.colors screen. On the d.colors
screen menu, commands appear in the right half of the screen, and the current status of categories
appears in the left half of the screen.
CATEGORIES
0 No Data
1 (Category 1 description)
2 (Category 2 description)
. ....
. ....
CATEGORY NUMBER:
RED 0 0%
GREEN 0 0%
BLUE 0 0%
Shift Incr: 10 3%
CATEGORY POINTER MOVEMENT
D/d down (cats) Move pointer to next category
U/u up (cats) Move pointer to previous category
COLOR MODIFICATIONS
R/r RED Increase/decrease RED intensity
G/g GREEN Increase/decrease GREEN intensity
B/b BLUE Increase/decrease BLUE intensity
I/i increment Increase/decrease increment
(of intensity shift)
h highlight Highlight current color
+/- shift colors Shift entire color table (up/down)
c save color Save color table
t toggle table Toggle to different color table
REPLOTTING SCREEN
* Replot screen Replots the screen
QUITTING
Q quit Quits program
Changing categories - The keys "d, D, u," and "U" are used to move to a different category. The lower
case letters move up, u, and down, d, the category list one category at a time. The upper case letters
move 10 categories at a time for fast movement. The cursor does wrap between the first and last
categories. The current category is noted on the text screen with an arrow, and is indicated on the
graphics screen by a box around the current color.

Changing colors - The color associated with the current category can be changed with the "R, r, G, g, B,"
and b keys. The upper case letters increase the intensities of red R, green G, and blue B for the current
category; the lower case letters decrease the intensities of these same colors for the current category.
Video devices make all the colors of the spectrum by mixing red, green, and blue. For those accustomed to
red, yellow, and blue being the primary colors, this can be confusing. For starters, yellow is made by
mixing red and green. The intensities are listed on the text screen in as percentages.

Keys I and i increase and decrease the percentage change that each keystroke of one of the color keys (R,
r, G, g, B, b) causes in its respective color. The increase increment is initially set to 10%. Thus,
pressing the R key would will increase the red component of the current category by 10%.

Highlight - The h key toggles between the current category color and the current highlight color. This
color is initially black but can be modified as above while in highlight mode. Blinking can be
accomplished by repeatedly striking the h key. When changing to different categories using the movement
keys as described above, while in highlight mode the category colors will be always left showing their
actual colors. Only one category is highlighted at any one time.

Saving the current color table - Pressing the c key will save the current color table as you have
modified it. This table will then be used next time you display or paint this raster map layer.

Color table toggle - Different types of color tables are suitable for different raster map layers. The
key t flips between the following color tables: red, green, blue color ramp; gray scale; smooth changing
color wave; random colors; and the saved color table.

Color table shift - The entire table is shifted up and down using the + and - keys.

Quitting the d.colors program - Pressing the Q key will cause you to quit the d.colors program. If
colors have been modified but not saved, d.colors will ask:
Colors changed
Save the changes? (y/n)
The user should type in y to save changes, or n to not save changes, before quitting the program. If
the user types n, the program will ask:
Quit anyway? (y/n)

NOTES

       The map whose color table is to be altered with d.colors must already be on display in the active display
       frame  on the graphics monitor before d.colors is run. This can be done using the command d.rast map=name
       (where name is a raster map layer whose color table the user wishes to alter).

       Some color monitors may not support the full range of  colors  required  to  display  all  of  the  map's
       categories  listed  in  the map's color table.  However, regardless of whether the user can see the color
       changes he is effecting to a map's color table, any changes to a map's color  table  made  with  d.colors
       that are saved will appear in the map's color table.

AUTHOR