Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages


home | help
BW-FB(1)			    BRL-CAD			      BW-FB(1)

       bw-fb - display a black and white bw image on a framebuffer

       bw-fb [-ahiczRGB] [-F framebuffer] [-s squarefilesize] [-w file_width]
	     [-n file_height] [-S squarescrsize] [-W scr_width]
	     [-N scr_height] [-x file_xoff] [-y	file_yoff] [-X scr_xoff]
	     [-Y src_yoff] []

       bw-fb reads a bw(5) format file from standard input if an input file is
       not given, and displays the image on the	currently selected
       framebuffer. The	environment variable FB_FILE specifies the current
       framebuffer; see	brlcad(1). Alternatively, the framebuffer may be
       explicitly specified by using the -F flag.

       By default, the bw file (and, automatically, the	requested framebuffer
       size) is	assumed	to be 512x512 pixels. Specifying the -a	flag causes
       the program to attempt to autosize. A table of common image sizes is
       consulted, and if any match the size of the input file, then the	width
       and height values associated with that size will	be used.

       If the -i flag is specified, the	image is output	from top to bottom.
       Customarily, bw files are stored	bottom to top, so this inverts the

       The -c flag causes the screen to	be cleared before the image is
       displayed. The default behavior is to overwrite the current image with
       the new image without clearing the screen.

       The -z flag will	zoom and center	on the image being displayed to	make
       it fill the display area.

       The flags -R, -G, and -B	select individual color	planes into which the
       image will be loaded. One or more can be	given. By default all three
       colors are written with the bw pixel value.

       The -w file_width flag specifies	the width of each scanline in the
       input file, in pixels. The -n file_height flag specifies	the height in
       scanlines of the	input file. Both are set to to the same	value via -s
       squarefilesize. (-W scr_width, -N scr_height, and -S squarescrsize
       perform these roles for the display device; if none of these three
       options are used, the display device uses the dimensions	of the input

       -x file_xoff, -y	file_yoff, -X scr_xoff,	and -y scr_yoff	will offset
       into the	file or	onto the screen	by the given amounts. The coordinate
       system for these	offsets	is first quadrant, with	the origin at the
       lower left corner of the	image.

       A bw(5) file contains sequences of pixels. Each pixel is	stored as one
       unsigned	char. The first	pixel in a bw file is the lower	left corner of
       the image. The pixels proceed from left-to-right	across each scanline,
       with scanlines being written from the bottom to the top of the image.

       fb-bw(1), bw(5)

       BRL-CAD Team

       This software is	Copyright (c) 1989-2019	by the United States
       Government as represented by U.S. Army Research Laboratory.

       Reports of bugs or problems should be submitted via electronic mail to

BRL-CAD				  03/02/2021			      BW-FB(1)


Want to link to this manual page? Use this URL:

home | help