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Creating and passing a class as a DLL Param

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Ok, I am trying to evaluate the Screen OCR SDK and I am having some trouble because the primary function I want to call in there DLL needs to be passed a pointer to a class. I can see that AutoIt supports DLL Calls and even some support for creating Structures to pass to DLL functions but how do I Create load and pass a class?

Here is a snipit from the header file they give to use with the DLL.

class TextractSource {
  TextractSource& BmpFile(const char *bmpFileName);
  TextractSource& Wnd(HWND);
  TextractSource& Rect(int ax, int ay, int bx, int by);
  TextractSource& DesktopWnd();
  TextractSource& TopWnd(const char *windowClass, const char *windowText);
  TextractSource& DeepWnd(const char *windowClass, const char *windowText);
  TextractSource& SubWnd(const char *windowClass, const char *windowText);
  TextractSource& SubDeepWnd(const char *windowClass, const char *windowText);
  TextractSource& FindLargestWindow();

  const char *BmpFileName; // used if != NULL
  HWND W; // used if != NULL
  int AX, AY, BX, BY; // used if BmpFileName == NULL and Wnd == NULL

TextractExport TextractSuccess Textract(TextractSource&, TextractDest&, 

I have only included one class for brevity but TextractDest is also a class. TextractSuccess is just a long.



P.S. I see many here prefer to use Tesseract but I am using Win7 which that has trouble with so I wish to try this method. OR would it be better to use VB and access both AutoIt and ScreenOCR with COM interfaces since both also have support for that method. I just don't what to make things more complex then they need to be. :)

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$tTextractSource = DllStructCreate("ptr BmpFileName;hwnd W;int AX;int AY;int BX;int BY;")
$pTextractSource = DllStructGetPtr($tTextractSource)
$aRes = DllCall("dllname.dll", "int:cdecl", "Textract", "ptr", $pTextractSource, "ptr", $pTextractDest)

Several things are assumed here: TextractSuccess is an enumeration (int), that class is a simple one, no polymorphism is involved and that the calling convention is __cdecl. Change the necessary fields.

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Change the necessary fields

???? I am also struggling with this since 2 days. :D

but cannot make it work.


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I'm also confused by this. Dont know how to return the recognized data to text at all.

Plz any help is greatly appreciated!

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