Libgodc: Write Go Programs for Sega Dreamcast

(github.com)

144 points | by drpaneas 6 hours ago

9 comments

  • drpaneas 6 hours ago
    I built a Go runtime that runs on the Sega Dreamcast, the 1999 console with 16MB RAM and a 200MHz SH4 CPU.

    You can write games in Go with goroutines, channels, garbage collection, and all the language features you'd expect. It compiles using gccgo and runs on real hardware or emulators.

    The project includes 3 game examples Pong, Breakout and Platformer, input handling, audio support, and integrates with KallistiOS (the Dreamcast homebrew SDK).

    * Star Here: https://github.com/drpaneas/godc * Documentation: https://drpaneas.github.io/libgodc/ * Video Tutorial: https://youtu.be/ahMl0fUvzVA

    Happy to answer any questions about the implementation!

    • danhau 5 hours ago
      I just wanted to say how impressive your documentation is. I expected an average readme.md, but not only is your readme great (the performance table is wonderful), but the full documentation is awesome. It pretty much answers all questions I had. Nice job! I wish all projects were like this.

      I also dig the documentation / book styling.

      • drpaneas 3 hours ago
        thanks @danhau, much appreciated, indeed documenting the process felt like another project of its own, so I am very happy to hear that :D
    • clktmr 4 hours ago
      Hey panos! I only had a short look at this for now, and it looks impressive! I'll have to dust off my Dreamcast and get this running.

      I looked at gccgo when porting the runtime to n64, but at the time it wasn't updated since go1.18. Can we use Go Generics on the Dreamcast? I see that gccgo is obviously needed to support SH4.

      • drpaneas 3 hours ago
        Hey Timur, long time no see, I hope all is going well :) No, you cannot use generics, they are not yet supported by gccgo.
    • simonw 1 hour ago
      This is a beautiful thing to exist. Much respect for building this.
    • lagniappe 3 hours ago
      You've made my entire WEEK! Thank you!
      • drpaneas 2 hours ago
        You've put a smile on my face reading your comment, thank you for your feedback, happy holidays :D
    • pjmlp 3 hours ago
      This is kind of cool, kudos for the effort.
      • drpaneas 3 hours ago
        you're very welcome :D Thanks!
  • phantasmish 5 hours ago
    > Replaces the standard Go runtime with one designed for the Dreamcast's constraints: memory 16MB RAM, CPU single-core SH-4, no operating system.

    24 total megabytes, with an M, of memory between system and video (another 8 there), single core 200mhz CPU, graphics chip runs at 100mhz. Shenmue runs on it.

    Glares at Teams.

    • pjmlp 3 hours ago
      I really don't get how Teams gets developed, not even the worst offshoring projects I have been part of, have reached so low in quality.
    • bttf 1 hour ago
      Would happily take work chat, video conferencing in network-enabled Shenmue over Teams, Slack any day
    • giancarlostoro 4 hours ago
      It baffles me that Microsoft can build an entire OS, and build and rebuild GUI stacks, and they couldn't build the Teams UI using C#???
      • federiconafria 2 hours ago
        Microsoft applications always look and behave as if they were ported to windows...
      • mfro 3 hours ago
        If they built Teams with a C# UI framework, it'd have to be rebuilt 4 times by now.
    • perching_aix 5 hours ago
      Could implement a custom Teams client on top of that. My biggest concern would be TLS and media decoding, but could just proxy the traffic and roll a text only client.

      I mucked about with Microsoft Graph a bit before, didn't seem too bad.

    • gethly 4 hours ago
      > CPU single-core

      This does not fare well for Go though.

      • jerf 3 hours ago
        It runs fine. It is perhaps a bit pricey for a 200MHz system, I'd certainly focus on having only a few of them and doing most of my work by looping over some sort of user-defined tasklet (or, in other words, "standard game architecture"), but it's not like Go requires multiple CPUs to work at all.
      • c2xlZXB5Cg1 3 hours ago
        Paging Mythbusters
      • lagniappe 3 hours ago
        Huh?
  • Imustaskforhelp 3 hours ago
    If someone is interested in running golang projects on niche hardware perhaps, one pro tip I can suggest but there is way to convert golang 100% into wasm (no js shim or anything required) and the only thing you would need is a wasm library

    You have to use golang from source (see the stackoverflow page https://stackoverflow.com/questions/76087007/golang-to-wasm-... )

    go install golang.org/dl/gotip@latest gotip download GOOS=wasip1 GOARCH=wasm gotip build -o main.wasm

    Although the way I did it is going into the gotip folder and then the binary folder which would contain the go compiler binary and then just use that path with

    GOOS=wasip1 GOARCH=wasm ~/sdk/gotip/bin/go build -o main.wasm

    Note that I forgot the exact path but it was similar to this but the point being that its super easy and simple :)

    I tried to do it and I can tell you that it works and it works for even the most latest versions of golang, all you need is a wasmengine which I suppose can be ubiquitous.

    I have built a solution where golang code gets converted to wasm and then we run a ssh server which then runs that wasm all in sandbox to create sandboxed mini golang servers :p I really love it although its a more so prototype than anything

    • gothink 18 minutes ago
      Looks like this is available (since Go 1.21 [0]), so no need to build from source anymore. Just did a quick 'hello world' test to verify and it worked:

          GOOS=wasip1 GOARCH=wasm go build -o main.wasm main.go
          wasmtime main.wasm
      
      If you're interested in wasm/wasi and niche hardware with Go, you should check out TinyGo [1] if you haven't already.

      [0] https://go.dev/blog/wasi

      [1] https://tinygo.org/docs/guides/webassembly/wasi/

  • nasretdinov 2 hours ago
    Nice project! Having just 16Mb of RAM does indeed sound like a real challenge for stock Go (not the TinyGo variant)! Even hello world is a couple megs, although I imagine Dreamcast isn't 64-bit, so the instructions are probably much shorter. Interesting to see anything written in it :)
  • steeve 14 minutes ago
    this is incredible
  • donatj 4 hours ago
    The "Effective Dreamcast Go" docs on this are fantastically well written. I've read much worse docs from major corporations.
    • drpaneas 3 hours ago
      Many thanks @dontaj much appreciated, indeed documenting the process felt like another project of its own, so I am very happy to hear that! The effective dreamcast Go was inspired from the old time classic https://go.dev/doc/effective_go :D
  • AdmiralAsshat 3 hours ago
    > Who is this for? > ... > Anyone who enjoys the challenge of severe constraints

    Remembering what a powerhouse the Dreamcast was when it came out, and how amazing games like Soul Caliber and Shenmue looked, it's hard to think of the Dreamcast hardware as "severely contained".

    • jerf 2 hours ago
      I find it a bit weird that I find it intuitive how things like the Super Nintendo did their work, and how modern games and systems work, but comparing the hardware specs of the Dreamcast/PS2/XBox/Gamecube era to the best of their output is where my intuition struggles the most. Not that the games of the era stand up to modern stuff, even when upscaled and texture-packed etc. in an emulator, but how they did it with so little oomph still amazes me.
    • drpaneas 3 hours ago
      yeah, been there, nostalgia hits hard. Dreamcast was a beast of its era, it even had Ethernet! Even the VMU was something extraordinary! Too bad SEGA had to cancel it :(
  • rpastuszak 3 hours ago
    I love this. The documentation is great and I've even learned a thing or two about golang from it! The logo makes me want to port Icy Tower to DC.
    • drpaneas 3 hours ago
      thanks @rpastuszak, much appreciated :D
  • karel-3d 3 hours ago
    I thought that gccgo supports only some old go version? Or subset of features? I will need to refresh my memory for sure
    • drpaneas 3 hours ago
      I am using sh-elf-gccgo (GCC) 15.1.0 which is ok-ish I guess. But in general gccgo tries to be close to Go, but they do not implement all the features. e.g. generics are still missing for example.
      • pjmlp 3 hours ago
        It appears stale to me, there seems no one is driving it any longer, and Ian Lance Taylor has moved on anyway.

        Maybe eventually the same can be tried with TinyGo, just as an idea.

        • drpaneas 2 hours ago
          problem is TinyGo uses LLVM, which doesn't support SH-4. The only reason I went with gccgo is due to SH4 target. In any case, I learned a ton of things doing this project :D