DISCLAIMER:
The authorship wasn't preserved by the time I (ducalex, 2020) found this source.
It's very difficult to trace back the history of this particular fork.
Best I can ascertain is that those two original authors created the bulk of the code:


Charles Mcdonald
================

Released his SMS emulator since 0.9 under the GPLv2+.
It stayed like so until after version 1.5 (source code to version 1.5 got lost unfortunately but we still have SmSPlus-GX thankfully).
After version 1.5, he decided to switch it to a non-commercial license, turning it proprietary again.
(The reason being he got legal threats from some companies using his emulator)

He also contributed modifications to sn76489.c, i contacted him and he told me it fell under the same license as Maxim's.

ekeeke
======
He worked on SMSPlus-GX, with several improvements such as improved accuracy, fixing bugs with most games etc...
It was originally designed for the Gamecube/Wii.
https://github.com/ekeeke/smsplus-gx

This fork also has code for Colecovision but Colecovision support seems to be a bit spotty and requires a BIOS.
The overscan code got removed because it was not useful and little to no SMS games make use of it.

