Langjam Gamejam: Build a programming language then make a game with it

langjamgamejam.com

102 points

birdculture

a day ago


47 comments

munificent a day ago

Oh my God, someone has discovered my kryptonite.

  • BSTRhino 21 hours ago

    Your book is awesome!

FjordWarden 19 hours ago

Challenge accepted, but no way I can finish this in 7 days even with a head start of a few months.

  • adamhartenz 19 hours ago

    So you are not accepting the challenge then. Sounds like you are over thinking or over scoping the problem.

    • mcpeepants 19 hours ago

      or just keenly aware of their own strengths, weaknesses, and time budget for this? the leap to “over scoping” is wild.

      • adamhartenz 17 hours ago

        I was just meaning, that if you think you can't do it in the timeframe, then you are making it too big for yourself. The rules are so loose that you could literally make a programming language that has a single command `run_my_awesome_game()` and fully impliment the logic etc in your language and library of choice. Obviously a trivial/useless example, but take it up a few notches and you could have something interesting. A DSL inside JSON can be very powerful.

shoo 21 hours ago

What is a minimal-ish programming language that could be used to express some interesting class of games?

It's easy to think of pathologically trivially useless "languages" that could "make a game". E.g. the single instruction language where the instruction P is defined to mean "execute a game of pong". Or a zero instruction language where the empty program is defined to mean "execute a game of pong".

Also easy to think of existing minimal programming languages that could technically be used to implement games. E.g. brainfuck is a beautifully minimal language with only 8 instructions, supporting character IO - so you could make a text based adventure game with it, but this would be unpleasant and there isn't anything about brainfuck that makes it suited to game dev.

Another idea could be to have a non Turing complete language where you declare data for entities etc to be executed by some game engine/runtime. E.g. it might be possible to define a language for declaring data & entities to express a few different but similar games (e.g. spanning pong --- breakout, or one specialised for simple card games, or so on).

  • torginus 5 minutes ago

    I think building an interpreted language with a basic but usable feature set - arrays, structs, expressions, control flow, functions etc. - is totally doable in a couple of days if you dont spend a lot of time ruminating on syntax and semantics.

  • ifidishshbsba 21 hours ago

    Let D be the language used to express the gameplay, C be an implementation of a compiler for D in a language L. You want to minimise the length of D + C across all languages L. This gives you a unique language D (a DSL) for each game which is the most semantically dense and expresses the essence of the problem domain the best.

    The language or languages D is discovered (not designed) and is the essence of the problem, will never change and is true in all universes. Any general purpose programming language solving the same problem (a solution using L) will have a structure of D with a bunch of boilerplate and design patterns (design pattern = boilerplate = hints at a special form in D).

    Using a hierarchy of these minimal languages D with one compiling into another for each little problem is the only way to get ‘clean code’ free of boilerplate.

    Software engineering is minimising D + C for all L

    • binary132 19 hours ago

      I’m hearing FORTH, but surely that’s not what you meant to say. :)

      • ifidishshbsba 19 hours ago

        I like to lisp but it might be time to finally learn FORTH :)

suioir 14 hours ago

What if you've already been working on a language for a while and want to use it instead of making a new one just for this?

  • ModernMech 35 minutes ago

    I would say the spirit of a jam is to start from scratch, but using parts and techniques you're used to is fine. e.g. repurpose your number parser but not the entire grammar and runtime. A lot of being successful at a jam is doing the right prep work so you're not making decisions and figuring things out at jam time.

macintux a day ago

Seems ideal for those grumbling about Advent of Code’s shortened schedule this year.

  • riffraff 23 minutes ago

    the time frame matches too, 14 to 20 gives you one day of rest after the last AoC, and then three more days to buy presents before Christmas that you forgot to co :)

WhyOhWhyQ 21 hours ago

Any recommendations on books / resources to read in order to participate as a beginner (language creator that is..., not beginner with programming games)?

  • shoo 21 hours ago

    Jack Crenshaw's 1988-1995 series Let's Build a Compiler [1]

    Graydon Hoare's 2002 talk `"One Day Compilers" or how I learned to stop worrying and love static metaprogramming` [2] (implements a compiler for a DSL that's a subset of makefile syntax in < 400 lines of code using ocaml toolchain)

    edit: on second thoughts, aiming to ship a game in a novel _compiled_ language in a 7 day language+game jam is probably a lot more optimistic than aiming for an interpreted language.

    [1] https://compilers.iecc.com/crenshaw/

    [2] https://www.venge.net/graydon/talks/

  • ifidishshbsba 21 hours ago

    Racket for sure, it goes straight to the heart of everything. You want simple macro compilers so you can see how simple it all is, not being confused by complex interpreters which totally obscure what is being done here.

  • BSTRhino 21 hours ago

    Crafting Interpreters!

amarant a day ago

Holy cow the diversity of skill sets required to do this is insane. I'll be very impressed at any Devs who takes this on solo.

  • cardanome a day ago

    I think you can make it as challenging or not challenging as you want. Just implement a simple Forth or Lisp in Lua and make a cute little game with Love2d or even just a simple text game.

    Maybe I expect too much from people but like at least being able to write a simple tree-walking interpreter is basic computer science education and who hasn't tried to make a game at least once?

    The problem is more that some people just like sharpening the saw and some people like cutting down trees. Both are valid. Some people get really into programming languages and tooling but never ship any product or vice versa. But people need to be skilled enough to do both.

    • amarant a day ago

      I think I might be the one to expect too much on second thought.

      Making a language and a game is one thing, making a good language and a good game is something else entirely.

      Very few people can do either of those on their own, let alone both.

  • pennomi 18 hours ago

    Easy, create a DSL that represents dialogue in a visual novel style game. Add some branching, looping, and variables, maybe some labels for jumping to and you’re good. Tada! You’ve basically reinvented Ren’Py.

  • sunrunner a day ago

    The crossover of language design/implementation and game development made me assume this was either a Jonathon Blow (Jai, Braid, The Witness) or Bob Nystrom project (Game Programming Patterns, Crafting Interpreters, 'Is There More to Game Architecture than ECS?' [1]).

    Either way, given the time constraints and requirements I'm expecting a lot of text adventures and rogue-likes.

    [1] https://www.youtube.com/watch?v=JxI3Eu5DPwE

  • adamhartenz 19 hours ago

    A programming language could be as simple as a domain-specific-language done in a JSON format. It could just abstract away a bunch of thing, and most of the logic would just be in your "game engine".

kderbyma a day ago

I have been doing something minor - not full language - but I am working on a couple DSLs for my game engine. The games themselves are interpreted by my engine console - then transpiled to webgl and JavaScript.

The DSL is for cutscenes and scripting dialogues and movements and transitions.

The idea was to have a screenplay like language that would run in my game engine so I can write the scenes like a script instead of like code.

Then I am using a LUA like subset for the core game logic.

I don’t think I would want to have the entire thing written in a custom language though, as that seems unnecessary

  • toisanji a day ago

    Ok would like to learn more about what you have been building, can we talk? I have thought of similar ideas.

pixelmelt 5 hours ago

If only it wasn't finals week

copx 21 hours ago

This is not as hard as it sounds as long as Forth and Lisp variants qualify.

You can write a basic Forth or Lisp interpreter in a day.

azhenley a day ago

I’m going to blog about whatever I end up building. I hope some of you will join me :)

Razengan a day ago

I've been wondering about this for some time, that how there really isn't a language that's made from the ground up just for coding gameplay logic.

Like we have SQL for databases, Julia etc for maths etc, but gamedevs still have to plod along in general-purpose languages with archaic conventions established 50 years ago by people who had nothing to do with games.

I'd love something with the syntax of GDScript and the features of Swift, with special constructs just for gameplay logic, which is often a hybrid between inheritance and composition, static and dynamic, declarative and imperative.

I've been toying with what would be the ideal syntax (for me), but I don't have the brains to actually make a language :')

  • BSTRhino a day ago

    I've actually spent the past 3 years making Easel (https://easel.games) specifically for gameplay logic. It's got behaviors as a first-class language construct, ownership and context is implied hierarchically, it's concurrent and event-driven to match how game worlds work, and the multiplayer is automatic because it's built into the fabric of the programming language.

    It also feels like a declarative language because of the high-level constructs, but it is actually imperative because (in general) things get executed in the step-by-step order you specify, which I think is important because games are full of sequences.

    It's been a lot of work but also a lot of fun! My aim is for this to be a great next step after Scratch for people learning to code but also a good model for how a more advanced game-making programming language could work in the future!

    • nextaccountic 9 hours ago

      If I understand correctly, the language is not open source, right? Not even the interpreter?

      That's a hard sell

    • Razengan a day ago

      This looks promising. How come I hadn't heard of it??

      My own ideas for an ideal syntax included keywords like "on" instead of "func" etc. (i.e. be totally event/signal driven)

      Taking a look!

      • BSTRhino 21 hours ago
        2 more

        Haha I wish I knew how to reach more people like you!

        Yeah exactly! I think the event-driven/signal-driven way of coding is the high-level way of coding a game, and so with Easel I was trying to make a game programming language where that is first class. It's different from the frame-by-frame state machine kind of model that is used by a lot of other game engines, and I find it's super productive.

        I know that I am unable to single-handedly compete with Godot or Unity so to make the scope achievable it's aimed at being a good 2D programming language for learners at this point. There's a surprising amount of similarity between Scratch and Easel because Scratch is also event-driven and concurrent like Easel. We often send our learners to Python or JavaScript and I've seen that they just lose engagement. The difference is bigger than just going from visual to text-based coding. Easel makes the gap closer and so I am hoping it'll be a great next step from Scratch into text-based coding.

        But I also hope Easel can add to the conversation and interest people like you as a example of how game programming languages could be made. One day I hope to actually bring Easel to more serious games, maybe bringing it to other engines or with its own 3D engine. One reason why I am leaning on making my own 3D engine (long term goal) is that in Easel, the multiplayer is automatic and it would be difficult to bring that to another engine.

        In either case it's great to meet someone who has been thinking about this kind of problem like I have.

        • Razengan 19 hours ago

          > I know that I am unable to single-handedly compete with Godot

          You could package your language as a GDExtension for Godot.

          I'm planning my fantasy language from the top-down, syntax first: how it would look like to users/developers to use it, then think about how to implement that language if ever :')

          Right now I'm just fiddling with a extension for VSCode/ium to syntax highlight the hypothetical language, then I'll put it up on a brainstorming repository on GitHub.

  • zzo38computer a day ago

    There are many that are specialized for different uses in games, such as:

    - ZZT-OOP

    - MegaZeux Robotic

    - ZIL

    - MESH:Hero

    - Free Hero Mesh

    - Super ZZ Zero

    - OHRRPGCE HamsterSpeak

    (There are probably a lot more that I had missed)

    All of these are specific to the specific kind of games being made with them, though; different kind of games will require a different kind of logic.

    MESH:Hero is specific to a specific kind of puzzle games, and Free Hero Mesh is a FOSS clone of MESH:Hero with a different syntax and more features.

  • Balooga a day ago

    There is OpenGOAL[1]. A re-implementation of the language that Naughty Dog used to created Jak and Daxter.

    [1] https://opengoal.dev/

  • Scramblejams a day ago

    Check out Jai, apparently if you ask nicely its author will let you use it. Unofficial docs here: https://pixeldroid.com/jailang/

    • Razengan a day ago

      Jai is just a C-like with manual memory management etc.

      I mean something that is divorced from hardware and just focuses on gameplay logic; let the engine continue to be in C++/Rust/whatever.

  • reactordev a day ago

    SQL is deterministic. Julia is deterministic. Gameplay is not deterministic. Constraints are arbitrary and there are no rules.

    • formula1 a day ago

      I think magic the gathering set a pretty good standard.

      • reactordev a day ago

        For Magic the gathering, sure. Not for Eve-Online. Not for Counter-Strike. Not for World of Warcraft. Not for Minecraft. Games are too diverse to limit yourself to a DDL.

BSTRhino a day ago

lol, I spent 3 years coding a game programming language...