Re: Adding lightuserdatas that are invisible to scripts

[Ignacio Burgueño <ignaciob@...>]

Ignacio Burgueño wrote:
> EHm, if I understood right, you want to access MyThing objects only from 
> C functions called by Lua. You can have it available as an upvalue of 
> the function. You do that when registering the functions in Lua:
>
> lua_pushlightuserdata(L, thing);
> lua_pushcclosure(L, your_C_function, 1);
> lua_setglobal(L, "yourFunctionName");


I forgot to tell how you access it later in your C function:

//////////////////////////////////////////////////////////////////////////
///
int your_C_function(lua_State* L) {
	MyThing* theThing = (MyThing*)lua_touserdata(L, lua_upvalueindex(1));

etc...


Also, Peter and Graham suggested using the registry. Which approach is 
faster? (i.e. less table lookups, etc)

Regards,
Ignacio