Calling the same function over and over again from C

["Framework Studios: Hugo" <hugo@...>]

Hi all!

 

I was just wondering if there is a way to speed-up calling the same function over and over again from C++ to LUA.

 

My point is, let's say we want to call the function "PerFrame()" (just for sake of argument), it would be something like:

 

    lua_pushstring(VM, "PerFrame");

    lua_gettable(VM, LUA_GLOBALSINDEX);

    lua_call(VM, 0, 0);

 

The first two lines are to seek a pointer to the actual function on the stack. It seems rather slow to have to convert the string to function every call. Is there a way to simply get whatever is on the stack (eg. a function) and push it onto the stack later on?

 

I'm thinking something like this:

 

Only one time we do:

 

    lua_pushstring(VM, "PerFrame");

    lua_gettable(VM, LUA_GLOBALSINDEX);

 

followed by something like:

 

    PerFrameFunction = lua_getfromstack(VM, 1);    // so I made up "lua_getfromstack" here...

 

...and per-frame we do something like:

 

    lua_pushtostack(VM, PerFrameFunction);

    lua_call(VM, 0, 0);

 

It would be nice to be able to do the same for a function in a table whilst reserving 'self'.

 

Did I miss how to do this or isn't it possible (yet? :) with LUA?

 

        Thanks,

                    Hugo