Different questions, migration attempt

[anass114]

Hi,

I am currently trying to move a old project that was build around with lua_tinker to LuaBridge , I want to use a modern lua wrapper that will let me to switch between lua engines and try them all easily. I have several issues because of how lua_tinker was handling function returns,calls....

As an example of one of the issues I have :

Consider the current function that it's returning a pointer to an object :

• void *lwRenderMan::AddScene(char const *pcID);

This function is returning a pointer to an object, this object can be used later in the lua code as parameter. so I don't really understand why I have the error InvalidTypeCast.

The second type of problems I have is :
g_ChatMgrClient:NoticeLevelColor_Add(1, 4294912559, 0xFF000000, true )

The third parameter is an unsigned int, it shouldn't be a problem but I am getting the error : IntegerDoesntFitIntoLuaInteger. I don't know ow to fix it and I already changed the type to __int64.

The third problem I am facing is this one.
This is the old code :

cpp class_<lwRenderMan>(pkState, "RenderMan")
		.def(pkState, constructor<PgRenderMan *>())
		.def(pkState, "AddScene", &lwRenderMan::AddScene)
		.def(pkState, "CleanUpScene", &lwRenderMan::CleanUpScene)
		.def(pkState, "CreateScene", &lwRenderMan::CreateScene)
		.def(pkState, "AddSceneByNo", &lwRenderMan::AddSceneByNo)
		.def(pkState, "RemoveScene", &lwRenderMan::RemoveScene)
		.def(pkState, "RemoveAllScene", &lwRenderMan::RemoveAllScene)
		.def(pkState, "InvalidateSceneContainer", &lwRenderMan::InvalidateSceneContainer)
		//.def(pkState, "PreloadScene", &lwRenderMan::PreloadScene)
		.def(pkState, "FindScene", &lwRenderMan::FindScene)
		.def(pkState, "Draw", &lwRenderMan::Draw)
		.def(pkState, "SetGraphicOption", &lwRenderMan::SetGraphicOption)
		.def(pkState, "SetUseAlphaGroup", &lwRenderMan::SetUseAlphaGroup)
		.def(pkState, "SetFrameDebug", &lwRenderMan::SetFrameDebug)
		;

`In the old code, the lwRenderMan is calling the constructor of PgRenderMan but with luabridge this type of operation isn't permitted, since there are checks to make sure the constructor we are calling is the correct one. So how to replace this code properly.

Thanks for your help

[kunitoki]

Refer to the section of the manual about constructors https://kunitoki.github.io/LuaBridge3/Manual#26---constructors

[anass114]

Thanks for your quick answer, this fix one of my problems. The second one is that I have a lot of functions that has predefined arguments for example :
extern lwUIWnd _lwActivateUI(std::wstring const& kID, bool const bModal = false, std::wstring const& pszNewID = _T(""));

In the lua code, I should be able to call this function with lwActivateUI("ID"); but in this case, luabridge is asking for all parameters. I saw that I can use std::optional. But since there are a lot of functions with predefined arguments, I want to know if there is another solution.

Thanks

[kunitoki]

I would use a single lambda with optionals and value_or to forward the values (but you will have to duplicate the default values).

Or alternatively you can use overloads and lambdas, like this:

.addFunction("_lwActivateUI",
    [](std::wstring id) { _lwActivateUI(id); },
    [](std::wstring id, bool modal) { _lwActivateUI(id, modal); },
    ...)

Last option is go fully manual and register a lua_CFunction, but you will have to get arguments manually from lua_State (this is the most verbose).