A retro font: Glass TTY VT220
Posted by jpluimers on 2026/05/04
Via [Wayback/Archive] Der Kneisner M100 – oder das “once in a lifetime project” | Computermuseum Visselhövede, about an IMSAI 8080 clone, I bumped into the VT220 based Glass TTY VT220 font and found some links of it and it’s modifications which are listed below by category
Github repositories with VT220 TrueType and bitmap fonts:
- [Wayback/Archive] GitHub – svofski/glasstty: GlassTTY: TrueType VT220 font
GlassTTY: TrueType VT220 font
- [Wayback/Archive] GitHub – lalo/VT220-mod-font: Modification to TrueType VT220 Font
Modification to TrueType VT220 Font
Single quote is straight instead of curved
- [Wayback/Archive] GitHub – htayj/DEC-Fonts: vt220 fonts in bdf, otb, and psf formats
This is a faithful recreation of the DEC VT220 fonts, in bitmap font format, using a VT220 rom dump and performing the same operations on the pixels as described in the VT220 technical manual.
- [Wayback/Archive] GitHub – Swordfish90/cool-retro-term: A good looking terminal emulator which mimics the old cathode display… has a whole bunch of retrocomputing based fonts in [Wayback/Archive] cool-retro-term/app/qml/fonts at master · Swordfish90/cool-retro-term · GitHub
- [Wayback/Archive] https://www.masswerk.at/nowgobang/2019/dec-crt-typography Simulate dot stretching in DECTerminalModern.ttf · GitHub points to the
_decterm.ttffrom VTX and the research by others below.
Background information:
- [Wayback/Archive] Hacking with Style: TrueType VT220 Font (2009) | Hacker News which pointed to a lot of interesting links, especially on how to get the phosphorous CRT feel back
- [Wayback/Archive] Raster CRT Typography (According to DEC) which is well worth reading. I think the best two pictures describing the effect are these:
VT220 character samples (80-columns mode).
1) as in ROM
2) normal size with dot stretching
3) rising and dropping phosphor flanks applied
4) phosphor bleed addedMind, how the counters “open up” in 3 and 4.
Apparent glyphs: VT100 (left) and VT220 (right).
- [Wayback/Archive] codepen.io/ivanca/pen/oNPZMLx simulating the CRT glow/fade effects on the
Glass_TTY_VT220.woff2font which has an example usage at [Wayback/Archive] Сhange the font in Twine – Authoring / Twine – The Interactive Fiction Community Forum - [Wayback/Archive] VTX Terminal Emulator: DEC Terminal Manual True-Type Font is defunct, but had a TrueType font lacking scan-lines (making it way too smooth for vintage usage) but adding a lot more characters (especially with diacritics) which is really practical.
- Preview [Wayback/Archive] DEC Terminal Modern Font | dafont.com
- Download: [Wayback] _decterm.ttf
- [Wayback/Archive] Hacking with Style: TrueType VT220 Font describes how the TrueType font with scan-lines was created.
- [Wayback/Archive] Hacking with Style: TrueType VT220 Font
- [WaybackSave/Archive] Hacking with Style: TrueType VT220 Font
It used the autotrace tips below to get the font started:
- [Wayback/Archive] Autotracing bitmaps in FontForge — FontForge 20230101 documentation
- [Wayback/Archive] Raster CRT Typography – the glyphs drawn by DEC VT100 and VT220 terminals #Typography #DEC #VintageComputing #Fonts « Adafruit Industries – Makers, hackers, artists, designers and engineers!
- Masswerk.at has some cool web-demos:
- [Wayback/Archive] RTerm VT-100 (Demo)
- [Wayback/Archive] RTerm VT-100 (Fancy Demo)
- [Wayback/Archive] RTerm (Demo 8032)
- [Wayback/Archive] Char8.js – Virtual Unicode 8-bit Character Generator
It would be cool if that technology could somehow be applied to native applications.
- [Wayback/Archive] VT220 Font Emulation has highly configurable CRT settings
Reference manuals:
- [Wayback/Archive] VT220 Technical Manual – Manx with these PDF versions:
- [Wayback/Archive] VT100 Series Video Terminal Technical Manual – Manx
- [Wayback/Archive] wwcm.synology.me/pdf/EK-VT100-TM-003 VT100 Series Video Terminal Technical Manual.pdf [Wayback PDF View/PDF View]
- [Wayback/Archive] bitsavers.org/pdf/dec/terminal/vt100/EK-VT100-TM-003_VT100_Technical_Manual_Jul82.pdf [Wayback PDF View/PDF View]
- [Wayback/Archive] vt100.net/dec/ek-vt100-tm-002.pdf [Wayback PDF View/PDF View]
- [Wayback/Archive] wwcm.synology.me/pdf/EK-VT100-TM-002 VT100 Series Technical Manual.pdf [Wayback PDF View/PDF View]
- [Wayback/Archive] bitsavers.org/pdf/dec/terminal/vt100/EK-VT100-TM-002_VT100_Series_Technical_Manual_2ed_198009.pdf [Wayback PDF View/PDF View]
- [Wayback/Archive] www.vaxhaven.com/images/0/00/EK-VT100-TM-002.pdf [Wayback PDF View/PDF View]
Wikipedia/wiki articles:
- VT220 – Wikipedia
- VT100 – Wikipedia the predecessor of the VT220 and could be extended to with a VT640 – Wikipedia which the VT220 could not: you would have to buy the VT240 variant of the VT220 for that
- VT320 – Wikipedia was the successor of the VT220; the VT330 added graphics and the VT340 colour
- DEC Special Graphics – Wikipedia (yes, included in the font!)
- [Wayback/Archive] DEC VT220 – Terminals
Queries:
--jeroen
The Wiert Corner - irregular stream of stuff 
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