I've seen vJoy. Has anyone heard of any actual on-screen virtual (touchscreen) joypad / game controller software that is open-source, for WIndows, or for Linux?

Everything that I have seen is not only closed source, but is no longer supported, save for TabletPro, and the best one that I have seen is Virtual Gamepad.

I'd like to see about getting something viable that we can all package with open source games, so that people with tablets can play them when they don't have a controller to attach, but they need traditional Gamepad style buttons.