3 ms·

Oh man, the first graphics code I ever wrote used Tektronix vector commands for drawing. It used ASCII escape sequences to specify diagonal lines on the screen,

by dhosek 11mo ago

Oh man, the first graphics code I ever wrote used Tektronix vector commands for drawing. It used ASCII escape sequences to specify diagonal lines on the screen, but, as I recall you could also tell it that instead of drawing a diagonal line, you could have it draw a rectangle with what would have been the endpoints of the diagonal line being opposite corners of the rectangle. These codes were supported by some VT-series graphics terminals as well as at least one dial-up terminal program on the PC back in the 80s so that’s what I targeted on my code (which was a DVI previewer for TeX running under VM/CMS). The original Tektronix terminals (I only ever saw one once) did all screen drawing with these vector commands (think the look of the classic Asteroids game which I think may have used a similar hardware interface to the CRT display), which naturally was not especially fast for ordinary text which is why hybrids like the abovementioned VT-series terminal (I think it was the 240/340/440 that had this) ended up supplanting the Tektronix displays.

SoftTalker 11mo ago
LSI ADM 5 terminals also had a vector graphics option (not sure if it was ever available for the ADM 3[a] nor if it was compatible with Tektronix graphics)
- PopAlongKid 11mo ago
  I owned an ADM3a and used it often back in the days of 300 and 1200 baud modems. My recollection is that it was just a dumb TTY.
  - housel 11mo ago
    The ADM3a was just a UART chip, RAM chips, character ROMs, and a bunch of 74LS chips to glue it all together. No CPU, and no way to generate graphics.
    - kragen 11mo ago
      Just to clarify, I think a lot of the Tek terminals that could generate graphics also lacked CPUs.
  - kragen 11mo ago
    The ADM3A was slightly more than a dumb TTY; it supported direct cursor addressing despite being made of SSI TTL chips. It was the main platform for vi. I bought a used one at a government surplus auction and, many years later, wrote an emulator. Thanks to termcap/terminfo, most TUI programs work adequately on an ADM3A emulator. No graphics, though, not even TRS-80-style pseudographics. Not even inverse video.
fao_ 11mo ago
You can switch a normal xterm to Tektronix mode and do the same commands today!
- anthk 11mo ago
  Some tools like plotutils and gnuplot (please, fix that hell of license) can still output to Tek displays, either real ones or emulated.
  - fao_ 11mo ago
    > (please, fix that hell of license) What do you mean?
    - anthk 11mo ago
      The gnuplot one.
      - kragen 11mo ago
        I think the Gnuplot license is uncontroversially a GPL-incompatible free software license? https://www.gnu.org/licenses/license-list.en.html#gnuplot https://www.gnu.org/licenses/license-list.en.html#gnuplot
    - somat 11mo ago
      I had to look it up, it's a little obnoxious but it's weird enough that I like it. The intent appears to be that modified versions of gnuplot have to be very clear and explicit that they are not gnuplot or made by the gnuplot team. anyway, here it is. At least it's still shorter than the gpl. * Copyright 1986 - 1993, 1998, 2004 Thomas Williams, Colin Kelley * * Permission to use, copy, and distribute this software and its * documentation for any purpose with or without fee is hereby granted, * provided that the above copyright notice appear in all copies and * that both that copyright notice and this permission notice appear * in supporting documentation. * * Permission to modify the software is granted, but not the right to * distribute the complete modified source code. Modifications are to * be distributed as patches to the released version. Permission to * distribute binaries produced by compiling modified sources is granted, * provided you * 1. distribute the corresponding source modifications from the * released version in the form of a patch file along with the binaries, * 2. add special version identification to distinguish your version * in addition to the base release version number, * 3. provide your name and address as the primary contact for the * support of your modified version, and * 4. retain our contact information in regard to use of the base * software. * Permission to distribute the released version of the source code along * with corresponding source modifications in the form of a patch file is * granted with same provisions 2 through 4 for binary distributions. * * This software is provided "as is" without express or implied warranty * to the extent permitted by applicable law.

by dhosek 11mo ago

SoftTalker 11mo ago

LSI ADM 5 terminals also had a vector graphics option (not sure if it was ever available for the ADM 3[a] nor if it was compatible with Tektronix graphics)

PopAlongKid 11mo ago
I owned an ADM3a and used it often back in the days of 300 and 1200 baud modems. My recollection is that it was just a dumb TTY.
- housel 11mo ago
  The ADM3a was just a UART chip, RAM chips, character ROMs, and a bunch of 74LS chips to glue it all together. No CPU, and no way to generate graphics.
  - kragen 11mo ago
    Just to clarify, I think a lot of the Tek terminals that could generate graphics also lacked CPUs.
- kragen 11mo ago
  The ADM3A was slightly more than a dumb TTY; it supported direct cursor addressing despite being made of SSI TTL chips. It was the main platform for vi. I bought a used one at a government surplus auction and, many years later, wrote an emulator. Thanks to termcap/terminfo, most TUI programs work adequately on an ADM3A emulator. No graphics, though, not even TRS-80-style pseudographics. Not even inverse video.

fao_ 11mo ago

You can switch a normal xterm to Tektronix mode and do the same commands today!

anthk 11mo ago
Some tools like plotutils and gnuplot (please, fix that hell of license) can still output to Tek displays, either real ones or emulated.
- fao_ 11mo ago
  > (please, fix that hell of license) What do you mean?
  - anthk 11mo ago
    The gnuplot one.
    - kragen 11mo ago
      I think the Gnuplot license is uncontroversially a GPL-incompatible free software license? https://www.gnu.org/licenses/license-list.en.html#gnuplot https://www.gnu.org/licenses/license-list.en.html#gnuplot
  - somat 11mo ago
    I had to look it up, it's a little obnoxious but it's weird enough that I like it. The intent appears to be that modified versions of gnuplot have to be very clear and explicit that they are not gnuplot or made by the gnuplot team. anyway, here it is. At least it's still shorter than the gpl. * Copyright 1986 - 1993, 1998, 2004 Thomas Williams, Colin Kelley * * Permission to use, copy, and distribute this software and its * documentation for any purpose with or without fee is hereby granted, * provided that the above copyright notice appear in all copies and * that both that copyright notice and this permission notice appear * in supporting documentation. * * Permission to modify the software is granted, but not the right to * distribute the complete modified source code. Modifications are to * be distributed as patches to the released version. Permission to * distribute binaries produced by compiling modified sources is granted, * provided you * 1. distribute the corresponding source modifications from the * released version in the form of a patch file along with the binaries, * 2. add special version identification to distinguish your version * in addition to the base release version number, * 3. provide your name and address as the primary contact for the * support of your modified version, and * 4. retain our contact information in regard to use of the base * software. * Permission to distribute the released version of the source code along * with corresponding source modifications in the form of a patch file is * granted with same provisions 2 through 4 for binary distributions. * * This software is provided "as is" without express or implied warranty * to the extent permitted by applicable law.