[luabind] Calling C++ functions in luawith objects as arguments

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Hello folks, i'm new to Lua/Luabind, i'm trying to call some C++ functions from a library with lua and i hope you can give me some help. The&nbsp;C++ functions are in a namespace: namespace ImageProcessor { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; void Invert(const CByteImage *pInputImage, CByteImage *pOutputImage) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; //Function declaration here! &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; }
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; void Canny(const CByteImage *pInputImage, CByteImage *pOutputImage, int nLowThreshold, int nHighThreshold) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; //Function declaration here!. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; }
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; void Canny(const CByteImage *pInputImage, CVec2dArray &amp;resultPoints, CVec2dArray &amp;resultDirections, int nLowThreshold, int nHighThreshold) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; //Function declaration here!. &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; } &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; ... &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; ... More functions here &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; ... } As you can see, the functions&nbsp;take several arguments, for example objects&nbsp;of the class CByteImage. In my C++ Code, I create&nbsp;these objects of&nbsp;the class CByteImage:&nbsp;&nbsp;
CByteImage *m_pInImage; CByteImage *m_pOutImage; m_pInImage = new CByteImage(int width, int height, CByteImage::eGrayScale); m_pOutImage = new CByteImage(int width, int height, CByteImage::ImageType); Later, i call for example the first two functions in my C++ code like this: ImageProcessor::Invert(m_pInImage, m_pOutImage); ImageProcessor::Canny(m_pInImage, m_pOutImage, 50, 50); Now i want to call these two C++ functions&nbsp;in lua, and that's the point where my problems begin: Nicolas told me, that i need to bind the functions in the namespace where they are defined. 
Now the thing with the objects. I don&rsquo;t really know how to handle these things. Do I have to bind the whole class CByteImage with the objects that I use as arguments of my function? Do I have to use the &ldquo;user definded types&rdquo; thing to tell lua how to handle these data types? Do I use pointers and make them available for lua?
What I&rsquo;ve done so far: lua_State* LuaState = lua_open(); // open the new state with luabind luabind::open(LuaState); // export the functions we want luabind::module(LuaState) [ // First Arg: Name of the function in Lua, Second Arg: Function in C++&nbsp; &nbsp;luabind::def("Invert", &amp;ImageProcessor::Invert) //I don't know exactly how to bind the arguments of the Canny function&nbsp; luabind::def("Canny", &amp;ImageProcessor::Canny, (void), (const CByteImage *), (CByteImage *), (int), (int)), //Binding of the CByteClass luabind::class_&lt;CByteImage&gt;("CByteImage") .def(luabind::constructor&lt;&gt;()) //Not sure how to binb objects luabind::object global_vars = luabind::globals(); global_vars["a"] = a; ];
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Now I have thought that I could call these two C++ functions in lua like this:
&nbsp;
--Lua
&nbsp;
test = Invert(m_pInImage, m_pOutImage)
test2 = Canny(m_pInImage, m_pOutImage, 50, 50)
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Again, is this correct or how do I have to do this?
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Thank you very much for your help
&nbsp;
Greetz Janik
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