leoagomes / 3ds.js

A JavaScript runtime for the Nintendo 3DS (Homebrew).

3DS.js

A (very early stage) (Homebrew) JavaScript runtime for the Nintendo 3DS.

Getting Started

• set up a 3DS build environment. (You'll also need Node and Yarn.)
• clone this repository (git clone https://github.com/leoagomes/3ds.js.git && cd 3ds.js)
• treat the /js subdirectory as your normal JavaScript aplication (Code works great!)
• run make
• use 3ds.js.3dsx however you like (emulator or hacked 3ds)

If you're fine with writing only ES5.1 code where the require system is really unstable (though nothing is really stable at the moment), you can bypass JS bundling and just write directly to an index.js in romfs.

Motivation

My ultimate goal for this project is to have something compatible enough with other JS runtimes as to be able to run both React (probably closer to React Native) and Pixi.js on some Homebrew devices -- initially the 3DS, with Switch support planned for the future (when I get a switch I can hack).

Since the project is in its infancy, it is really limited at the moment. In order to start somewhere, I'm first implementing a couple non-standard interfaces for things like IO and ctrulib access so maybe we can bootstrap a community around this project.

At the moment, I don't expect anyone to be able to write games using JavaScript on the 3DS. I'm unsure about performance and there isn't really a way to draw graphics to the screen as there are no JS bindings to citro3d or citro2d -- though that is planned! I think this will currently work more as a more friendly way to write text-based tools for the 3DS, without having to use C (at least directly).

Features

Currently, the only api that is stable is whatever Duktape provides out of the box plus console.log. Everything else is really subject to change.

If you write your app using the template provided in /js, you'll get the latest JavaScript with support for many features through core-js polyfills. I'm not completely certain how well they will work.

Roadmap

At the moment, I believe these will be the next steps towards the first release:

• node-like module system
  • current require (poorly) emulates node behavior
• proper file I/O -- even if completely synchronous
• promise polyfill
• a version of 3DS.js that is able to run index.js from the SD card (no compilations)
  • a JS app loader app capable of launching other JS packages?

After that, I intend on working on the following (not necessarily in that order):

• Duktape debugger over wifi
• ctrulib JS bindings
• citro3d JS bindings
• citro2d JS bindings
• async I/O
• fetch -- big goals!
• maybe something like curl JS bindings
• something akin to a React Native stack

Philosophy

As mentioned above, at this stage I'm more interested in having something that (barely) works and improving it from there. This means that this project is currently missing a lot of optimizations. We're probably wasting memory and leaving performance on the table -- which I agree may be problematic on a device as limited as the (original) 3DS.

There may also be security issues with this code... as always, only run code you trust on your devices.

License

Aside from "external" libraries (such as duktape), which are released under their own licenses, all code in this repository is released under an MIT-like license that you should definitely check out at LICENSE.

Contributing

Please do! Your contribution really does help. From documentation mistakes to test improvements, to killer JS bundler templates or great polyfill, every piece of code helps!

I currently prioritize code that's easy to read and maintain rather than too cleverly optimized code, though that will eventually be necessary for performance. Start a discussion and help improve the project!

If you're going to contribute, just don't be an asshole. You know it when you're being one, everyone else probably does too. There really is no need to be one.