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Here is how i made it possible to call C++ from LUA. I want to build Multiplayer game in Leadwerks. But i couldn't find networking libraries and threading libraries that would make it usable in Lua. So i build a Networking client in C++ with libcurl and libpthread . But i want to still use the Lua scripting on the prefabs since a lot of work is already done for me here. And also programming in Higher level languages is just faster. I decided to use the libtolua++ libraries, since this is already build into Leadwerks. I work on Ubuntu 15.04. Here the tolua++ libs are installed with: sudo apt-get install libtolua++5.1-dev The tolua++ program needs a pck file which shall contain the c++ like seudo code that is translated into lua classes. My package: $#include "shot.h" class ShotListener { ShotListener(); ~ShotListener(); void shot(Object* oEntity, float damage); float getHealth(Object* oEntity); }; I have made two functions. One to emit shots detected on the Entities from the Lua scripting. Another to get the current health status from C++ side. My actual ShotListener.h class looks like this: #pragma once #include "App.h" #include "Leadwerks.h" using namespace Leadwerks; class ShotListener { private: public: ShotListener(void) { } ~ShotListener(void){} void shot(Object* oEntity, float damage) { App *app = App::getInstance(); Entity * entity = (Entity*)oEntity; app->entityShot(entity, damage); return; } float getHealth(Object* oEntity) { App *app = App::getInstance(); Entity * entity = (Entity*)oEntity; float value = app->getEntityHealth(entity); return value; } }; As you can see i changed the default App class into a Singleton so that i can get the App object from the instances of ShotListener that is used from Lua. Having placed these two files in the same folder i ran the following function from the terminal: tolua++5.1 -o tolua_shot.cpp -H tolua_shot.h -n Shot shot.pkg This generated two files tolua_shot.cpp and tolua_shot.h that i included in my C++ project along with the shot.h file. This way i can do a self.shotListener = ShotListener:new() In the Script:Start() function in mu Lua objects and a self.shotListener:shot(self.entity, self.hits) When Hurt is called in the Lua object. After this i just had to sort out all the Segmentation error bugs because of multithreading. I forgot to mention that the ShotListener Lua also needs to be initialized in the main.cpp before app->Start() with the following: if (Interpreter::L==NULL) Interpreter::Reset(); tolua_ShotListener_open(Interpreter::L);

Hi, Over the past few weeks, I've been looking into how to link objects to classes created in C++. Since I prefer to code in C++ but still value the flexibility of Lua, the goal of mine is to simply link a Object whether be a pivot, CSG, or a model to a C++ Class while having all the advantages of the Flowgraph communication, and such. When I came across ToLua++ (This File), I thought this would fix my problem. The plan was to link an object to a class by doing something like this in the Start function: self = self.class:new() However, if the lua-gluecode.cpp is included in the project at all without any calls from the Interpreter, the game will just downright crash if any object has a lua script attached to it, even the ones included in the SDK. I thought it was lua-gluecode.cpp calling my class wrong, but if it's NULL, it still does the same thing. luacommands.pkg: class BaseEntity; lua-gluecode.cpp: /* ** Lua binding: luacommands ** Generated automatically by tolua++-1.0.92 on 01/15/15 17:09:26. */ #ifndef __cplusplus #include "stdlib.h" #endif #include "string.h" #include "tolua++.h" /* Exported function */ TOLUA_API int tolua_luacommands_open (lua_State* tolua_S); /* function to register type */ static void tolua_reg_types (lua_State* tolua_S) { tolua_usertype(tolua_S,"BaseEntity"); } /* Open function */ TOLUA_API int tolua_luacommands_open (lua_State* tolua_S) { tolua_open(tolua_S); tolua_reg_types(tolua_S); tolua_module(tolua_S,NULL,0); tolua_beginmodule(tolua_S,NULL); tolua_cclass(tolua_S,"BaseEntity","BaseEntity","",NULL); tolua_beginmodule(tolua_S,"BaseEntity"); tolua_endmodule(tolua_S); tolua_endmodule(tolua_S); return 1; } #if defined(LUA_VERSION_NUM) && LUA_VERSION_NUM >= 501 TOLUA_API int luaopen_luacommands (lua_State* tolua_S) { return tolua_luacommands_open(tolua_S); }; #endif App.cpp:: #include "App.h" using namespace Leadwerks; App::App() : window(NULL), context(NULL), world(NULL), camera(NULL) {} App::~App() { delete world; delete window; } Vec3 camerarotation; bool freelookmode=true; bool App::Start() { //Initialize Steamworks (optional) if (!Steamworks::Initialize()) { System::Print("Error: Failed to initialize Steam."); return false; } // Call ToLua++ if (Interpreter::L == NULL) Interpreter::Reset(); tolua_luacommands_open(Interpreter::L); //Create a window if (System::GetProperty("fullscreen") == "1") { window = Window::Create("Test v0.0", 0, 0, 1024, 768, Window::FullScreen); } else { window = Window::Create("Test v0.0", 0, 0, 1024, 768, Window::Titlebar); } //Create a context context = Context::Create(window); //Create a world world = World::Create(); //Create a camera camera = Camera::Create(); camera->Move(0,2,-5); //Hide the mouse cursor window->HideMouse(); std::string mapname = System::GetProperty("map","Maps/start.map"); Map::Load(mapname); //Move the mouse to the center of the screen window->SetMousePosition(context->GetWidth()/2,context->GetHeight()/2); return true; } bool App::Loop() { //Close the window to end the program if (window->Closed()) return false; //Press escape to end freelook mode if (window->KeyHit(Key::Escape)) { if (!freelookmode) return false; freelookmode=false; window->ShowMouse(); } if (freelookmode) { //Keyboard movement float strafe = (window->KeyDown(Key:) - window->KeyDown(Key::A))*Time::GetSpeed() * 0.05; float move = (window->KeyDown(Key::W) - window->KeyDown(Key::S))*Time::GetSpeed() * 0.05; camera->Move(strafe,0,move); //Get the mouse movement float sx = context->GetWidth()/2; float sy = context->GetHeight()/2; Vec3 mouseposition = window->GetMousePosition(); float dx = mouseposition.x - sx; float dy = mouseposition.y - sy; //Adjust and set the camera rotation camerarotation.x += dy / 10.0; camerarotation.y += dx / 10.0; camera->SetRotation(camerarotation); //Move the mouse to the center of the screen window->SetMousePosition(sx,sy); } Time::Update(); world->Update(); world->Render(); context->Sync(); return true; } If you want my BaseEntity.cpp/.h stuff, I can send it over, but it does absolutely nothing but print something on spawn. And as I said before, the luacommands.pkg can be totally empty and not be calling anything and it will still crash. If anyone could help, or recommend me better ways of doing this, I'll appreciate it. Thanks!