CAT-FB(1)

NAME
cat-fb — display a troff C/A/T document on a framebuffer

SYNOPSIS
cat-fb [-hcoO] [-F framebuffer] [-C r/g/b] [-{sS} squarescrsize] [-{wW} scr_width] [-{nN} scr_height] [troff_files]

DESCRIPTION
cat-fb reads a troff(1) C/A/T phototypesetter document from the named file(s), or from standard in if no file is specified. The document is converted to a bitmap using the Berkeley font files from /usr/lib/vfont and libfont(3), and is either displayed on the currently selected framebuffer, or output as a pix(5) format image. 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 requested framebuffer size is assumed to be 512x512 pixels. Specifying the -h flag changes the size to 1024x1024.

The -w scr_width and -W scr_width flags specifies the width of each scanline for the display device, in pixels.

The -n scr_height and -N scr_height flags specifies the height of each scanline for the display device.

-s squarescrsize and -S squarescrsize set both the height and width to the size given.

By default, the text bitmaps are overlaid on top of the image resident in the current framebuffer. However, the -c flag causes the screen to be cleared before the image is displayed. The -O flag specifies that the background image is to be read instead from standard input. This forces the troff(1) input to be stored in a temporary file which is given as a parameter. If the -o flag is given, then no framebuffer operations are performed, and the output image is written to standard output. If this option is specified, and the -O option is not given, then the -c (clear) operation is silently forced.

The default color of the text is full intensity white. This can be changed by specifying the text color option -Cr/g/b where each of "r", "g", and "b" represent integers from 0 to 255, and the slashes (``/'') are entered literally.

NOTES
Because the way that text is processed (top to bottom) is different from the way that pix(5) files are processed (bottom to top), any pix(5) files input or output will need to be processed with an inversion -i flag on other tools.

EXAMPLES
Simple white on black typesetting:

  tbl files | eqn | troff -t - | cat-fb -c

Typesetting on top of a nice shaded background:

  tbl files | eqn | troff -t - > doc.tr
  pixbackgnd -i 160 200 | cat-fb -O doc.tr

Typesetting upside-down:

  tbl files | eqn | troff -t - | cat-fb -o | pix-fb

SEE ALSO
pix-fb(1), fb-pix(1), troff(1), libfb(3), libfont(3), pix(5)

DIAGNOSTICS
``cat-fb: -O ignored, stdin used for C/A/T code''. An attempt was made to take both the overlay picture and the C/A/T code from stdin.

``cat-fb: X off right edge of screen''. An attempt was made to typeset the character ``X'' beyond the right edge of the screen/file.

FILES
 .railmag
 /usr/lib/vfont/railmag

AUTHOR
Ronald B. Natalie

SOURCE
SECAD/VLD Computing Consortium, Bldg 394
The U. S. Army Ballistic Research Laboratory
Aberdeen Proving Ground, Maryland 21005

BUG REPORTS
Reports of bugs or problems should be submitted via electronic mail to <devs@brlcad.org>.