See my PR.(Not finished yet,I'll do more)
Didn't run well on camera
,but it's still a good idea.I suggest use C to write some draw libs for speed and mem(maybe we need a dynamic link lib support
),and use lua for main game logic.
Or,full rewrite in C and compile it into a module.
P.S:See this:
Notch's minicraft,a 2d version of minecraft,made by notch in ludum dare 22 contest,and other developer's plus version:
Minicraft+