Parsing the C64 Bubble Bobble Wind Currents
150 points by geon 5 days ago | 34 comments
  • wzdd a day ago |
    Nice analysis, and cool to see how simple it is to get quite a satisfying effect. Also quite fun to see that the level symmetry was indeed exploited multiple ways to save space. If the author is here, they write '"@123" are the first 4 entries in the default c64 character set' but likely meant @ABC.
    • geon a day ago |
      Dammit, fixed.

      And thanks!

      • djmips 10 hours ago |
        I very much enjoyed the article but the subtext that 6502 assembler is worse than Cobol is quite the slight as a life long 6502 coder. ;-)
  • actionfromafar a day ago |
    In two player mode, still even today, C64 Bubble Bubble is one of the best casual games. I can sit down almost anyone on the couch and they'll enjoy at least a few rounds, experienced video game players or not.

    That the game design and implementation cuts through FOUR decades of time to be enjoyable says something. There are many old games which still are good but not as accessible to a modern audience.

    There are even more old games which are impressive even in retrospect, but don't play well today.

    • mbajkowski a day ago |
      Indeed, my kids who are 5 and 8 enjoy it about just as much as Mario Kart 8 - especially the earlier levels which require less of the balloon jumping.
    • fidotron a day ago |
      Bubble Bobble, arcade and ports, were wildly popular especially in the UK, to the point that when I was working as a game dev in London in the early 2000s if you mentioned what you did to a random person the chances were they would start lamenting how complicated these modern 3D games were and how after a bit of digging it would turn out they just loved Bubble Bobble/Rainbow Islands etc.

      I think it's up there with Asteroids, Defender and Robotron honestly.

    • dfxm12 a day ago |
      Is there anything specific about the C64 version that sets it apart from the arcade, NES or other versions? As for design, old arcade games had to both look and be fun fast in order to earn your quarter. As for implementation, the story goes that the original source code for the arcade game was lost and all ports had to be done by reverse engineering an arcade board.
      • _sys49152 a day ago |
        c64 was just so much smoother playing + looked better visually. not choppy.
      • geon a day ago |
        I don’t think source was ever used for porting in those days anyway. The asm wasn’t directly portable for sure.

        The c64 levels are pretty close to the arcade, apart from the arcade having 26 rows of tiles rather than the c64’s 25.

        The nes versions levels deviate wildly. Some have been moved and some are replaced.

        • ahartmetz a day ago |
          Not at all? If I was porting a game, I'd at least want to make important behaviors 100% true to the original - accelerations, jumping physics, hitboxes, speeds... these are pretty tedious to reverse-engineer without source. OTOH, the source was assembly and the binaries could be disassembled...
          • beagle3 a day ago |
            Not at all.

            Frame rates varies widely, resolutions varied widely. The exact behavior was in e.g. pixels/frame, and you had to work hard to get the same feel on a 50hz 256x192 4Mhz z80 ZX Spectrum, as you did on the 60hz 160x200 1Mhz 6510 C64 ; Also abilities differed widely : C64 had hardware sprites, tile (text) mode and hardware scrolling; Spectrum had nothing but a frame buffer (it did have a much faster memory copy instruction, LDIR, but that didn’t compete with hardware scrolling).

            And the original arcade, of course, had multiple playfield with hardware scaling, and often game-specific hardware (in the early days at least)

          • fidotron a day ago |
            I think you underestimate how different the original game and port targets were, and overestimate how capable the machines the porters had access to as workstations were.

            To take a famous extreme example: https://en.wikipedia.org/wiki/Chase_H.Q.

            Arcade video: https://www.youtube.com/watch?v=Dfz2qofmZx0 ZX Spectrum video: https://www.youtube.com/watch?v=s2aYrkofKHM

            And that ZX Spectrum port is brought up all the time when people talk about great Spectrum games, while it is, at best, kind of themed the same way as the arcade original.

            In the case of Bubble Bobble the hardware was: https://system16.com/hardware.php?id=646

            That's 3 Z80s, not counting the sprite hardware.

            The result was in practice a lot of this would be done by playing the arcade machines and then attempting to replicate the feel on the target (which is why so many ports miss easter eggs), and at that the C64 did remarkably well here.

            The Atari 2600 Pacman is the canonical example of this going wrong.

            • actionfromafar a day ago |
              Atari 2600 Ms Pacman is good though.
          • duskwuff a day ago |
            > If I was porting a game, I'd at least want to make important behaviors 100% true to the original - accelerations, jumping physics, hitboxes, speeds... these are pretty tedious to reverse-engineer without source.

            You're wildly overestimating how professionally done a lot of video game ports were in that era. It wasn't uncommon for home computer ports to be written by a single developer whose only access to the original was being able to pump a pocketful of quarters into it at their local arcade.

          • fredoralive a day ago |
            There's a bit about the port as a section of a longer discussion about publisher Firebird: https://youtu.be/LWHJomIX_As?feature=shared&t=2297 . Which does state that yep, it was mostly made by playing the arcade game lots then doing the best they could. They apparently did have some documentation... in Japanese.

            AFAIK "here's an arcade PCB, write this for the C64 / Speccy" wasn't an uncommon thing back then. Arcade perfect wasn't really a thing for the 8 bit micros...

      • geon a day ago |
        No source is truly lost when you have a disassembler. :D
        • kmoser a day ago |
          Quibble: no source for that target architecture. If the source included pragmas for other targets, you'll never know what they were.
    • jandrese a day ago |
      Was the C64 version available as a cartridge or did you have to load it in via the painfully slow floppy drive or worse off of a tape?

      An advantage of the NES version is you could be playing it within seconds of hitting the power button, which made it great for casual pick up games.

      • fidotron a day ago |
        This reply is amazing because it's like people from totally different universes trying to communicate.

        The sort of people playing Bubble Bobble in the 80s on C64s would almost certainly have been doing so from tape, more than likely pirated. The NES was not really on the radar of these people at all.

        I heard of C64 piracy operations in northern europe where the local radio station would play C64 games for recording on sunday afternoons. That's how pervasive it was.

        • ajuc a day ago |
          Or you could live in Poland and only get C64 and (clones of) NES in 90s. And copyright only started being a thing in like 1993. So before that public radiostations broadcasted computer software sometimes :) And there were open air markets with pirated games in the center of most big cities. That's where CD Projekt RED guys started - by selling games they got by paper mail from abroad on these markets.
        • georgemcbay a day ago |
          Speaking as an old person who learned to code as a young teenager on the C64 (motivated in part by the ability to pirate games because I otherwise had no means to afford them), by the C64 era disk drives were a lot more prevalent than tape in my experience, at least here in the USA.

          The C64 users of the time that I knew, including myself, were all using the 1541 floppy drive (keep the screwdriver handy so you can quickly pop the top off when it inevitably needs to be realigned because of how common it was for anti-piracy measures of popular games to knock the drive head around).

          Still slow (but probably sped up by a 'fast load' cartridge if you were and avid user), but not quite as bad as the PET-era cassette tape situation.

          And back to the main topic -- I played a lot of multiplayer Bubble Bobble on the C64 with my sisters and cousins. Enough that I can still easily recall the theme song decades later.

          • Sharlin a day ago |
            I believe tape was much more common in Europe, the 1541 was expensive. My second-hand C64 (my first computer!) did come with a 1541, but that wasn't until the early 90s…
            • fidotron a day ago |
              Yep. By the era in question in Europe if you had money for a C64 disk drive you were buying an ST or Amiga instead.

              I don’t think many on the western side of the Atlantic appreciate how relatively poor, and tight fisted, much of Europe was and remains, even the good bits.

              • Wonkey 11 hours ago |
                Where I grew up in Europe we had the 1541 disk drive before the Amiga came. Several people I grew up with had the C64 bread bin, the 1541 floppy drive, the cassette tape and a 9 pin printer. I only met one guy who had an Amstrad.
            • geon a day ago |
              Exactly. Everyone used tapes and turbo loaders.

              The screen of "Turbo 250 By Mr. Z" felt like magic. Not only could you load a game in one minute instead of ten, but you suddenly had extra commands available in the basic prompt.

              https://csdb.dk/release/?id=20633

      • beagle3 a day ago |
        Fast loaders were a thing after 1987, and we’re plenty fast, even the tape ones were acceptable. Not cartridge fast, but 10 sec floppy disc load for games, about 30-60 secs for cassette.
  • Dwedit a day ago |
    Back in 1998, a level editor was made for the Arcade version of Bubble Bobble, named "Patch-A-Bobble". This level editor revealed the directional airflow in the levels.
    • kstenerud 10 hours ago |
      I had a lot of fun writing that! The data structure allowed for airflow to be specified freely for everything except the very top and very bottom - for those you had a choice between solid brick, flow up, and flow down (for each side).
      • Dwedit 8 hours ago |
        It was that utility that inspired me to write the TI83 version of Bubble Bobble.
  • taki a day ago |
    I still love that game - and this is a thing of beauty. Thank you for sharing.
  • drpgq 21 hours ago |
    I remember the seventh row, third column board being annoyingly difficult for the C64 version.
  • kstenerud 10 hours ago |
    Haha, reminds me of a Windows utility I wrote a looong time ago called Patch-A-Bobble:

    https://www.romhacking.net/utilities/142/

    It was a win32 app that would read all the graphics from the Bubble Bobble ROM itself, then let you edit the levels, save them, and patch the modified levels back into the ROM so that you could play them on MAME (or even put them in an arcade cabinet).

    edit: Oh, I actually uploaded it to github: https://github.com/kstenerud/patch-a-bobble