f1() -- some function!
f2() -- some other function!

-- need class instance if you don't bind it with the function
print(m1(sc)) -- 24.5
-- does not need class instance: was bound to lua with one 
print(m2()) -- 24.5

-- need class instance if you 
-- don't bind it with the function
print(v1(sc)) -- 30
-- does not need class instance: 
-- it was bound with one 
print(v2()) -- 30

-- can set, still 
-- requires instance
v1(sc, 212)
-- can set, does not need 
-- class instance: was bound with one 
v2(254)

print(v1(sc)) -- 212
print(v2()) -- 254