Register classes with Lua/toLua

["Erik Glans" <erik.glans@...>]

Hello!

 

This is my fist post on this message board :)

 

I use Lua and toLua an I have created a class that have this 2 functions:

///////////////////////////////////////////////////////////////////////////////
// Name:  RegisterClass
// Description: Register en C++ class that Lua can see.
//
bool ZFScript::ExposeClass(char *szName, lua_CFunction o_LuaGet, 

                           lua_CFunction o_LuaSet)
{
 // check if type is already registered
 bool bAlreadyExist = true;
 if(m_kExposedClasses.find(string(szName)) == m_kExposedClasses.end())
  bAlreadyExist = false;

 

 if(bAlreadyExist)
 {
  printf("SCRIPT_API: Class [%s] already exposed %s\n", szName);
  return true;
 }

 

 // Create Lua tag for Test type.
 lua_pushcfunction(m_pkLua, o_LuaGet);
 lua_settagmethod(m_pkLua, tolua_tag(m_pkLua,szName), "getglobal");

 

 lua_pushcfunction(m_pkLua, o_LuaSet);
 lua_settagmethod(m_pkLua, tolua_tag(m_pkLua,szName), "setglobal");
 
 m_kExposedClasses.insert(string(szName));
 return true;
}

 

///////////////////////////////////////////////////////////////////////////////
// Name:  ExposeClass
// Description: Register a C++ object that Lua kan se.
//
bool ZFScript::ExposeObject(const char* szName, void* pkData, char* szClassName)
{
 lua_pushusertag(m_pkLua, pkData, tolua_tag(m_pkLua, szClassName));
 lua_setglobal(m_pkLua, szName);
 return true;
}

 

The problem is that I must have 2 static functions in every class that I want to expose to Lua.

class Foo

{

...

  

static int LuaSet(lua_State* pkLua)
  {
   Foo* var=(Foo*) lua_touserdata(pkLua,2);
   Foo* val=(Foo*) lua_touserdata(pkLua,3);
   var=val;
   return 0;
  }

 

  static int LuaGet(lua_State* pkLua)
  {
   Foo* var=(BasicConsole*) lua_touserdata(pkLua,2);
   lua_pushusertag(pkLua, var, tolua_tag(pkLua, "Foo"));
   return 1;
  }

 

...

 

};

 

Because I expose my classes and objects like this:

 m_pkScript = new GameScript(); // GameScript inherit public by ZFScript

 m_pkScript->ExposeClass("Foo", Foo::LuaGet, Foo::LuaSet);
 m_pkScript->ExposeObject("pkFoo", pkFoo, "Foo");

 

Is there a better solution? This is not a very nice way to do it...

 

Thanks! /Erik.