/!\ Work-in-progress

Expose C-functions to lua using a single function call which wraps the given function and automatically manages the lua stack.

An explanation of the inner workings can be found at my webpage

Primary goals

• Utilise templates and parameter packs to deduce function signature - the API should be able to be used without passing types
• Avoid recursive templates and unnecessary code generation
• Avoid (or enable opt-in) dynamic memory allocation
• Allow out-parameters (pointers)

Requirements

C++20 for lua_register.hpp. Catch2 and lua 5.3 for the tests

Features

Currently implemented:

• const char* and primitive type parameters.
• const char* and primitive type return values.
• Output parameters via pointers (multiple returns).
• C-functions taking an array as a pointer. Max 4 members.
• Variadic string functions. Max 32 parameters and 256 max total length; configurable by MAX_VARIADIC_ARG_COUTN and STRING_BUFFER_LENGTH.
• Passing custom types to/from Lua via template specialisation - LuaRegister::LuaGetFunc, LuaRegister::LuaSetFunc, and LuaRegister::GetDefault.
• Simple hard-coded default values.

Not implemented:

• Configurable array max length, though upping the limit is trivial.
• Error messages for wrong types general error handling.

Usage

lua_register.hpp contains documentation. The only function needed from the outside is one of the Register functions.

An example file which registers most of the Dear imgui widgets is found in the repo as lua_example.cpp.

Examples

lua_example.cpp contains examples of the following:

• Custom parameter types ImVec2, ImVec4
• Simple function calls ImGui::Begin
• Overloaded function registration ImGui::BeginChild
• Variadic function registration ImGui::TextX
• C-function taking an array as a pointer ImGui::DragFloatX

Some examples can be found through the tests.