Writing plugins using the native C/C++ API

IOLITE’s C/C++ API offers the possibility to create highly modular engine and editor plugins in C, C++, or any other language that supports C bindings.

Important

The API documentation is provided via the header file itself.

Important

Native plugins are a feature of IOLITE PRO. You’re free to evaluate plugins in the free version, but loading non-default plugins will add a watermark to the editor and game.

Writing a simple plugin

To write your first plugin, head over to our GitHub repository and download the latest version of the API header file.

The header file is completely self-contained and should compile with any C or C++ compiler on any of the supported platforms. Simply set up a project that outputs a DLL and you are good to go. If you’re unsure how to proceed, take a look at the minimal sample plugin which shows how to use CMake to set up a plugin project for multiple platforms.

All a plugin has to do is provide the following three functions, as shown in the minimal plugin example in the repository:

#include "iolite_api.h"

const struct io_api_manager_i* io_api_manager = 0;

IO_API_EXPORT io_uint32_t IO_API_CALL get_api_version()
{
  // Inform IOLITE which version of the API you are using
  return IO_API_VERSION;
}

IO_API_EXPORT io_int32_t IO_API_CALL load_plugin(const void* api_manager)
{
  // Ensure we can keep accessing the API manager after loading the plugin
  io_api_manager = (const struct io_api_manager_i*)api_manager;

  // Do something with the API manager, set up your plugin, etc.

  return 0; // Return a value < 0 to indicate that the loading of your plugin
            // has failed (depedency not available, etc.)
}

IO_API_EXPORT void IO_API_CALL unload_plugin()
{
  // Clean up here
}

After compiling your plugin, create/modify the plugins.json file in the root directory of the application. The structure of the file is depicted in the section Loading plugins.

If everything worked out okay, you can fire up IOLITE and check the results via the console log output ([F2] opens up the console) or the [Plugin Manager] available via the [Plugins] menu in the menu bar.

Writing a custom scripting backend

IOLITE’s Lua integration is provided via a native plugin using the C API, and the full implementation is available via our public GitHub repository. The Lua implementation can be a great starting point if you plan to roll your own custom scripting backend.