Use the Foreign Function Interface (FFI)

Demonstrates usage of the FFI to interact with the Visionary Render Lua environment.

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.

// 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]);

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.