Use the Foreign Function Interface (FFI)

Introduction

The FFI is an interface to the internal scripting engine used by Events in Visionary Render. This is a Lua environment.

The FFI allows a native plugin to call Lua functions directly by preparing arguments and invoking the function by name.

Any function available to an Event Script in Visionary Render, or to a Lua plugin, is also available to native plugins.

C

// construct an array of arguments
HFFIVar args[] = {
  VRFFIMakeString("Hello")
};

// prints "Hello" to the Lua console
HFFIVar retVal = VRFFIInvoke("print", args, 1);

// must clean up all var handles
VRFFIFree(retVal);
VRFFIFree(args[0]);

C++

HFFIVarR args[] = {
  VRFFIMakeString("Hello")
};

// prints "Hello" to the Lua console
HFFIVarR retVal = VRFFIInvoke("print", HFFIVarR::raw(args), 1);

Limitations

The FFI is limited to returning one value from an invoked function. If the invoked function returns more than one value, all but the first are ignored.