The UNIX PC 3B1 system font, for modern computers

Convert the venerable AT&T UNIX PC font to the modern BDF bitmap format

The unixpc-system.8.bdf font file that this tool produces has, for your convenience, been committed to the root of this repository. The font makes your Linux terminal look charmingly like the classic UNIX desktop machine of yore:

I want to thank Timothy Allen for his library bdflib which made this project not only possible but also fun.

Installation and Use

Create your ~/.fonts directory if it does not already exist, install the BDF font file from this repository, and activate ~/.fonts as an X Windows font directory. An xterm should then be able use the font:

mkdir -p ~/.fonts
wget -P ~/.fonts https://raw.githubusercontent.com/brandon-rhodes/unixpc-font-bdf/master/unixpc-system.8.bdf
mkfontdir ~/.fonts
xset fp+ ~/.fonts
xset fp rehash
xterm -fa '' -font '-unixpc-system-*' -fb '-unixpc-system-*'

Studying the UNIX PC base filesystem

The Makefile in this directory can not only build the font file, but also offers a few intermediate targets that might interest fans of the old UNIX PC:

• make fs downloads the UNIX PC 3B1 "Foundation Set" and "Development Set" diskettes from www.unixpc.org and extracts them into the directory fs, giving you a base UNIX PC filesystem to browse right on your modern machine.

• make font.h copies into the repository root the C header file that defines the UNIX PC binary .ft font file format, in case you want to study it yourself.

• make foundation.cpio and make development.cpio download the raw floppy diskette contents without extracting them to a local directory, in case the raw CPIO archives are of more use to you.

Other fonts

If you want to study the other fonts that came with the UNIX PC, run make fs as described above, and then look inside the filesystem image:

$ ls -l fs/usr/lib/wfont/

You will find terminal fonts, several fonts offering special characters and drawing characters, and large-format fonts with much more detail than the basic 9x12 pixel font that the UNIX PC used by default. You can use the conversion program to turn any of them into a modern BDF file:

$ python convert.py fs/usr/lib/wfont/PLAIN.R.E.24.A > tmp.bdf

If it turns out I have accidentally hard-coded anything in the script that’s fatal for one of the other fonts, just open an Issue and we’ll take a look at it! I wasn’t, I’ll admit, aiming for production code here.

Design note

Pixels on the UNIX PC screen were not square: they were tall rectangles. This means that the UNIX PC 9x12 terminal font did not, in fact, display squarish little characters with a 3:4 aspect ratio, but taller and more elegant characters.

To simulate their appearance on a modern display where pixels are squares, the convert.py script sets an internal value scale = 2 that produces 2 rows of pixels for every 1 input row of pixels. While this, strictly speaking, produces an error in the other direction by making the letters stretch taller than they would have on the UNIX PC, the result is visually more beautiful and more readable.

If someone were to convert the font into a scalable format, then experiments could be made with intermediate ratios that even more closely matched the UNIX PC display. But I am happy enough with the double-height version of the font and am not at this point planning further experiments.