NOTE: This is merely a proof-of-concept!!! It will probably never reach the point of being even remotely playable!! Currently the repository just contains yet another Pong clone, along with a few demo programs.
An opensource engine for the game CrossCode.
Apparently a similar project exists, made by some Korean developers: https://github.com/Knabin/crosscode. They even have a demo video which predates my project (the implementation, not the idea though). I wish I could understand Korean.