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  • Screwtapello 41 days ago | parent | on: Resurrecting Infocom's UNIX Z-Machine with Cosmopo...
    When the game Beyond Zork starts up, it asks the Z-Machine interpreter what platform the interpreter is running on. If it's a platform that supports graphics, the game uses a custom font to draw an on-screen map; if it's a platform that only supports text, it does not try to draw the on-screen map. If it's a VT220, it uses the VT220's built-in special characters to draw the map.

    Probably nobody was buying a special VT220 edition of Beyond Zork, I think that version was used by the developers working at Infocom, who did their work on a minicomputer and terminals. I believe it was a VAX, rather than a Unix minicomputer, but it wouldn't surprise me if the Unix Z-Machine interpreter had a similar story behind it.

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    • KODust 41 days ago
      Beyond Zork’s map drawing code will also produce an ASCII art variant of the map for systems that can’t easily handle the custom font, like, IIRC, the Apple II.

      The Infocom dev machine was a DECSystem 20 (PDP-10 architecture) until circa 1988, when they ported tools to the 68020-based Mac II.

      I expect they thought the Unix source would be a good basis for future non-Unix development; comments in the source itself allude to this possibility; I’m just wondering if it was used in any shipping product. I suspect it wasn’t.

      reply
  • Screwtapello 60 days ago | parent | on: The MAD Computer Program
    Today I learned that the C64 does not have a Bresenham algorithm in the firmware, since apparently the Commodore version of The MAD Computer Program includes its own Bresenham implementation in BASIC.
    • bmonkey325 60 days ago
      Atari didn’t either. I remember seeing bresenham implemented in Atari BASIC and it outperformed the built in BASIC command DRAWTO significantly without assembly support.

      Seems like something Apple/Woz would do but I cannot confirm. Or deny.

      • KODust 59 days ago
        Some good commentary here on the Apple II's BASIC graphics primitives https://github.com/fadden/fdraw/blob/master/docs/manual.md

        quote below from the Lines section ---

        The Applesoft routine isn't quite the same as the standard Bresenham algorithm, because it doesn't move diagonally. Consider a line from (0,0) to (50,10) -- gently sloping down and to the right. The standard algorithm would plot exactly 51 pixels, one in each horizontal position. The "pen" always moves one pixel right, but sometimes also moves down.

        In Applesoft, the "pen" can move either right or down, but can't do both at once. This results in lines that feel thin when near horizontal or vertical, but become thicker as they approach 45 degrees. This reduces performance, because Applesoft draws twice as many pixels for a diagonal line as the basic algorithm. It can also be visually jarring when animated, because lines get very thick when near diagonal.

  • Screwtapello 84 days ago | parent | on: Text Based Adventure Game
    If you don't get an answer here, you might want to ask on intfiction.org which has a lot of text adventure historians as regulars.
    • sc4556 84 days ago
      thank you! I'll let this play out a few days. I have felt like I have been in a maze of twisty little passages, all alike on this one for a long time.
      • qingcharles 82 days ago
        If you find the answer, please come back and let us know :)
        • sc4556 81 days ago
          Thank you! I certainly will. I have looked several times over the years. Perplexing.
  • Screwtapello 170 days ago | parent | on: This GameCube Mini Is Downright Adorable
    Is there any Gamecube emulator of note besides Dolphin?
  • Screwtapello 229 days ago | parent | on: The Annotated Hacker Test
    There's another (less complete, but maybe more detailed?) attempt to annotate the Hacker Test here: https://github.com/hwayne/hacker-test-history
  • Screwtapello 279 days ago | parent | on: Reverse Engineering Myst
    Things in this video:

    - a brief tour of HyperCard and how the original Mac version of the game works

    - how to deprotect the game and open it in the regular HyperCard editor

    - Some fun development tools, and cut content found in the game's code

    - The HyperCard protection password revealed after thirty years

    Also check the comments for a confirmation from Rand Miller himself!

    • qingcharles 276 days ago
      Sounds awesome. Gonna watch this now.
  • Screwtapello 281 days ago | parent | on: Jungle Music in 90s Games
    It was really interesting to read about the history of the jungle genre, and hear some examples, but I was hoping for a bit more about why jungle was so well suited to 90s games. My guess was going to be that jungle as a genre is so heavily sample based, and the 1990s was when game hardware became powerful enough to play samples (not just beeps and FM synthesis), with decent polyphony and fidelity, in complex sequences. Not many other styles of music are built in quite that way, so jungle was a natural fit.

    The article does talk about the availability of CD audio being a factor, but that doesn't explain the N64, nor why jungle specifically (lots of genres benefit from the availability of CD audio).

    • pikuma 278 days ago
      Thank you for the OP for sharing our blogpost. And I agree, I will expand to include more info on the why jungle was a good choice (besides good timing).
      • qingcharles 276 days ago
        This was such a well-written article. Thank you so much.

        I was working in game dev in the UK in this era, and I can tell you, all the devs, artists, musicians were mostly listening to what is now called EDM. I was in charge of music tooling at one point, but never had the chance to sway the music to some 180bpm DnB lol

        • pikuma 271 days ago
          Great stuff! I was speaking to one of the developers from Psygnosis (they worked in the MS-DOS port of Wipeout) and he also mentioned the same thing. And living in London for some years it was clear that jungle and drum'n'bass just fit the place.
          • qingcharles 269 days ago
            Did you write the article on PlayStation 1 gfx that was trending recently? Another fantastic article.
            • pikuma 237 days ago
              Yes, I did. Sorry for the late reply.
  • Screwtapello 311 days ago | parent | on: In defense of an old pixel
    This is the pixel font editor featured in Marcin Wichary's recent talk about the history and beauty of pixel fonts: https://www.youtube.com/watch?v=SDI8ubVZi7w
  • Screwtapello 337 days ago | parent | on: Real VT102 emulation with MAME
    Since I wrote that article, I think MAME has learned a slightly more convenient way of interacting with PTYs, but I never got around to investigating again.
  • Screwtapello 346 days ago | parent | on: Apple IIc USB-C Power Delivery Adapter
    It's cool that USB PD means that a simple active connector and a standard USB power supply can replace all kinds of historical power supply adapters. However, it's kind of a drag that now there's a bunch of USB connectors that are invisibly incompatible - some USB power supplies support the Power Delivery protocol, some don't, and I don't know if it's safe to plug one of these "needs Power Delivery" devices into a power supply that does not support it.

    How terrible an idea would it be to make an adapter that boosts the un-negotiated 5V that USB provides up to the 15V that (apparently) the IIc requires?

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