Switch GBA Emulator
Motivation
Homebrewing / Hacking a switch is too much of a dangerous affair for me personally and after learning there is a browser I tried to get it running in there. Turns out it is (sort of) possible.
Preview (Old UI but still relevant)
This project is meant as an experiment of what is possible and not to be used commercially. This is a hobby project and therefore I won't commit to offering help / maintaining / updating this project unless I choose to do so.
Information / How it's done
This project makes use of the Switch browser that comes up when trying to verify / sign in with certain DNS providers. I won't explain how to do this here but if are capable of setting this up you certainly will also be able to find that information yourself.The way the Switch handles B is a bit different if there is an iFrame present on the page. In this case B will actually navigate the iFrame back first before navigating back the actual page (or reloading it). This is crucial for my workaround. With the use of postMessage I always immediately return to a "navigated" state of the iFrame.
This is a modified and heavily towards switch tailored version of [crowdsourced-gba](https://github.com/vinnyoodles/crowdsourced-gba) by vinnynoodles.
Planned features
- [Done] Save states
- [Done] Gamepad API
Button Layout
Thanks to the Gamepad API I was able to remove most of the onscreen buttons and enable hardware button support.
Since v1.0.2 custom layouts are also supported. Just click the cogs at the top of the screen during rom selection to open the options menu. The left side shows the GBA key and the right side shows the currently assigned Switch key.
Developer info
The current layout file is found at `src/backend/layout.json`. A default configuration is always saved at `src/backend/layout.backup.json`, which is also used for the reset.
Usage
The emulator in it's entirety is ready to be pulled as a docker image. It runs on and exposes port 8888 by default.
Docker Images
Latest release
bfriedrichs/switch-gba:release-latest
Latest master (possibly unstable)
bfriedrichs/switch-gba:latest
Latest dev (most likely unstable)
bfriedrichs/switch-gba:dev
Older release
bfriedrichs/switch-gba:release-{version}
I'm not distributing any roms, so you will have to make a folder roms with your .gba files directly in it.
Example
docker run -d -v $(pwd)/roms:/home/roms/ --name switch-gba -p 8888:8888 bfriedrichs/switch-gba:release-latest
Versions
1.0.2
- Added custom button layouts
- Code restructuring
1.0.1
- Add fix for content size warning after alerts are open for too long
- Minor changes
1.0.0
- Initial release
- ROM selection
- Gamepad support
- Turbo mode (2-20x speed)
Misc issues / features
Some other stuff that I build / had to deal with.
-
Page size too large, refresh the pageThis popped up every now and then and then made the window lag out continously even whenCancelis pressed. I changed frompngto uncompressedwebpimages and added logic that disconnects the WebSocket if there's no input for more than 10 seconds. The WebSocket automatically reconnects if there's new input. -
Turbo modeWhen enabled turbo mode makes the emulator tick at times the speed of its usual execution (e.g. 600 vs 60 fps for x10). The output rate of frames remains 60 so the switch doesn't choke up. -
AudioSadly the switch doesn't seem to have an exposed audio API for the web browser. I'm still looking for a solution since various feature checkers actually report a prefixedAudioContextto be present but I didn't have luck with that yet.
Resources
Switch supported HTML features http://html5test.com/s/a77ccd45f1540617.html