Question Calling C++ dll in Visual basic

[Satanka_Patka]

Hi All,


I have a dll which has one function and I want to call this function from Visual Basic 2008. I tried every solution, but I couln't get it to work,

The original declaration is the following in C++

extern "C" CSSM_API void GetOptimalCSSMShaderParams(
float* outProjMatrixArray
,float* outCtrlMatrixArray
,int* outProjNumber
// LIGHT INFO:
,const float* inLightPos
,const float* inLightDir
,float inLightRange
,float inLightAngle
// CAMERA INFO:
,const float* inViewMatrix
,const float* inProjMatrix
// CSSM INFO:
,float inFocusRange
,bool columnMajorMatrices=false // Used for OpenGL
);

I defined in VB as follow

Public Declare Function GetOptimalCSSMShaderParams Lib "CSSM.dll" ByRef outProjMatrixArray() As MTV3D65.TV_3DMATRIX, ByRef outCtrlMatrixArray() As MTV3D65.TV_3DMATRIX, ByRef outProjNumber As Integer, ByVal inLightPos As MTV3D65.TV_3DVECTOR, ByVal inLightDir As MTV3D65.TV_3DVECTOR, ByVal inLightRange As Single, ByVal inLightAngle As Single, ByVal inViewMatrix As MTV3D65.TV_3DMATRIX, ByVal inProjMatrix As MTV3D65.TV_3DMATRIX, ByVal inFocusRange As Single, Optional ByVal columnMajorMatrices As Boolean = False)

I always get the following error when I wan to call the function :

System.Runtime.InteropServices.MarshalDirectiveException was unhandled
Message="PInvoke restriction: cannot return variants."


I tried to use the marshal unmanaged types, but I was no lucky.

Does anybody any idea?

Thanks

Robert

 

[Satanka_Patka]

Anybody? No soulution?