Commands
SetXY(x,y) -- set position to (x,y)
F(x) -- move forward x pixel
B(x) -- move back x pixel
R(x) -- turn right x degree
L(x) -- turn left x degree
The lua vm was reference from lua.vm.js
Since javascript did not support coroutine, I used lua script in C2. It could call c2 function in lus script in my lua vm plugin.