сделал общий интерфейс для открытия PdfReader, Djvu, Xps

DesktopEditor/common/officedrawingfile.h

+#ifndef _OFFICE_DRAWING_FILE_H
+#define _OFFICE_DRAWING_FILE_H
+
+#include <string>
+class IRenderer;
+class CApplicationFonts;
+class CFontManager;
+class IOfficeDrawingFile
+{
+public:
+    virtual ~IOfficeDrawingFile() {}
+
+    virtual bool LoadFromFile(const std::wstring& file, const std::wstring& options = L"",
+                                const std::wstring& owner_password = L"", const std::wstring& user_password = L"") = 0;
+
+    virtual void Close() = 0;
+
+    virtual std::wstring GetTempDirectory() = 0;
+    virtual void SetTempDirectory(const std::wstring& directory) = 0;
+
+    virtual int GetPagesCount() = 0;
+    virtual void GetPageInfo(int nPageIndex, double* pdWidth, double* pdHeight, double* pdDpiX, double* pdDpiY) = 0;
+    virtual void DrawPageOnRenderer(IRenderer* pRenderer, int nPageIndex, bool* pBreak) = 0;
+    virtual void ConvertToRaster(int nPageIndex, const std::wstring& path, int nImageType) = 0;
+};
+
+#endif // _OFFICE_DRAWING_FILE_H