Please help with DLL plugin.

[anon_57322307]

I’m currently testing out the DLL plugin feature of Unity, but haven’t been able to get it working. I plan on building the application for Windows so naturally I’m trying to use a DLL. If anyone can shed some light on how the plugin system work, I’d greatly appreciate it.

Ok, first here’s the code for my DLL built with Visual Studio 2005:

#include “stdafx.h”

#ifdef _MANAGED
#pragma managed(push, off)
#endif

#ifdef __cplusplus
extern “C” {
#endif

//DLL Entry
BOOL APIENTRY DllMain( HMODULE hModule, DWORD ul_reason_for_call, LPVOID lpReserved)
{
return TRUE;
}

/* Add two integers */
_declspec (dllexport) int add_num(int a, int b)
{
return((int)(a+b));
}

#ifdef __cplusplus
}
#endif

#ifdef _MANAGED
#pragma managed(pop)
#endif

Here’s the code I used in Unity. I attached it to a GUIText object:

using UnityEngine;
using System.Runtime.InteropServices;
using System.Collections;

public class TestScript : MonoBehaviour
{
[DllImport (“GAPlugin”)]
private static extern int add_num (int a, int b);

void Awake () {
int tempvar;

guiText.text = “Start Test”;
tempvar = add_num(10, 16);
guiText.text = “End Test”;
}
}

I built the application and ran it in Windows. All I’m getting is the “Start Test”. I never see the “End Test”. It appears to be stuck at the function call to the DLL.

[anon_57322307]

Looks like I found the problem. It appears that Unity places the DLL file inside the /Data/Plugins folder, but the executable is looking for the DLL in the same directory as itself. It was getting stuck since it was unable to locate the DLL. After I copied the DLL out to the root with the executable, it found the DLL and everything worked.