fbcolor [-F framebuffer] [-s|-S squaresize] [-w|-W width] [-n|-N height] [-h]FBCOLOR(1)
NAME
fbcolor - interactively pick a color on a framebuffer
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SYNOPSIS
DESCRIPTION
fbcolor is an interactive color picking facility. It draws a set of red, green, and blue color bars in the lower-left corner of a framebuffer, fills the remainder of the display with the current color, then reads single-character commands from standard input to edit that color. Editing is done by manipulating the framebuffer color map, so the display updates instantly as parameters change. The chosen color may be adjusted in either RGB (red, green, blue) or HSV (hue, saturation, value) space.
As the color is edited, fbcolor prints the current RGB and HSV values on the terminal so they can be recorded for later use with tools such as fbclear(1).
The interactive commands fall into two groups: those that select which parameter to edit, and those that change the value of the selected parameter.
The keys r, g, and b select the red, green, or blue channel, while h, s, and v (or i) select the hue, saturation, or value. The / key steps through the parameters in that order.
+ and . increment the selected parameter by one; - and , decrement by one; > and < change it by 16. Values range from 0 to 255 and wrap in both directions. Typing ? prints a command summary, and q, Q, or a carriage return / line feed exits the program, restoring the original color map.
OPTIONS
- -F framebuffer
-
Specifies the framebuffer device to use. If not given, the environment variable FB_FILE is used to select the display device (see brlcad(1)). If FB_FILE has not been set, the default device for your system is used.
- -s squaresize
-
Sets both the width and height of the framebuffer window to squaresize pixels.
- -S squaresize
-
Same as -s.
- -w width
-
Sets the width of the framebuffer window to width pixels.
- -W width
-
Same as -w.
- -n height
-
Sets the height of the framebuffer window to height pixels.
- -N height
-
Same as -n.
- -h
-
Prints a usage summary and exits.
EXAMPLES
Example 1. Pick a color, then paint the whole framebuffer with it
fbcolor -F /tmp/myfb -s 512
fbclear -F /tmp/myfb 200 100 50Open a 512x512 framebuffer file and interactively dial in a color, reading the printed RGB triple from the terminal (for example rgb=200, 100, 50). Once a pleasing value is found, the recorded RGB values are passed to fbclear(1) to flood the same framebuffer with that exact color.
SEE ALSO
brlcad(1), fbclear(1), fbcmap(1), fbgrid(1)
AUTHOR
BRL-CAD Team
COPYRIGHT
This software is Copyright (c) 1989-2026 by the United States Government as represented by U.S. Army Research Laboratory.
BUG REPORTS
Reports of bugs or problems should be submitted via electronic mail to devs@brlcad.org