[Swig-user] How can I include SWIG-wrapped C++ in Mono / Unity 3D on Windows?

[Katherine R. <ill...@gm...>]

Hello all,

My goal is to get a toy C++ library wrapped using SWIG, and accessible
to C# / Mono scripts in Unity (the game engine) on Windows.

Following a few SWIG- and Unity-specific tutorials I have generated
two DLLs in Visual Studio 2013 and added them to the Unity project.
But accessing the toy method at runtime is failing as follows...

DllNotFoundException: example
CSharpExampleLib.examplePINVOKE+SWIGExceptionHelper..cctor ()
Rethrow as TypeInitializationException: An exception was thrown by the
type initializer for SWIGExceptionHelper
CSharpExampleLib.examplePINVOKE..cctor ()
Rethrow as TypeInitializationException: An exception was thrown by the
type initializer for CSharpExampleLib.examplePINVOKE
CSharpExampleLib.example.fact (Int32 n)
SimpleController.Start () (at Assets/scripts/SimpleController.cs:10)

One atypical thing I needed to do was add the following library
references and namespace to the autogenerated C# wrapper files:

using System;
using System.Runtime.InteropServices;

namespace NameOfWindowsDll {
...
}

I made several attempts to correct common for causes of the
DllNotFoundException error (build as Release, build as 32-bit, check
Dependency Walker, etc) to no avail. Is there something SWIG-specific
I am missing?

I've made detailed notes of my process at
https://stackoverflow.com/questions/27534054 but if there's any other
detail I can provide, please let me know.

Many thanks,
Katherine