Advice for building cores with Emscripten?

acdimalev · 8 August 2018 05:41

I’m looking for some advice, documentation, or reference material on getting started with building cores with Emscripten. For other platforms, a core can be built as a shared object file and dropped into the “cores” directory for Retro Arch to load at runtime. I know this is different with Emscripten, and that the cores need to be linked directly against Retro Arch in some way, but I have yet to figure out how that is done.

Hoping to figure this out for game development jams like Ludum Dare, where having a web version of an entry greatly increases exposure.

Thanks!

gouchi · 11 August 2018 16:58

Hi,

There is some documentation.

Interesting please keep us updated about the game development jam

Thank you.

acdimalev · 13 August 2018 18:51

Thanks for the link!

WIth some additional help from #libretro IRC, I’ve got building with Emscripten mostly figured out. I didn’t know about dist-cores.sh, and there’s a bit of a file renaming dance required. Here’s some (admittedly terse) notes for anyone interested.

gist.github.com

https://gist.github.com/acdimalev/3872c9fec2535645060a2e8396e1fb37

libretro-emscripten-notes.md

set a base directory (just to make things easier)

    $ basedir="$(pwd)"


set up Emscripten
https://kripken.github.io/emscripten-site/docs/getting_started/downloads.html

    $ cd "$basedir"
    $ git clone https://github.com/juj/emsdk.git

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It’s a little rough around the edges, but I successfully submitted a Ludum Dare Jam entry! I missed the Compo deadline by half a day, mostly getting back up to speed on building games with C. I’ll admit that I’m a little rusty.

https://ldjam.com/events/ludum-dare/42/please-dont-step-on-my-hat

please-dont-step-on-my-hat

Feedback on how I’m hosting the game / using Retro Arch is welcome. I did some tweaking to the HTML / JS to make the game easy to load for somebody who isn’t familiar with Retro Arch, but I suspect it’s less than ideal.

There are also a few gotchas / things that aren’t quite working right with trying to upload the games to either http://itch.io/ or a self-hosted site. When I get a chance, I’ll try to document my findings there too.

It’s really exciting being able to build this kind of game in a single weekend. I’m definitely going to use Libretro again for the next game development jam and encourage others to try as well.

hunterk · 13 August 2018 18:53

That’s awesome! Let us know of any cool stuff you crank out. I’m always impressed by the quality of what people can come up with in these 1-2 day game jams.