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#if !defined(AFX_MEMDC_H__CA1D3541_7235_11D1_ABBA_00A0243D1382__INCLUDED_)
    #define AFX_MEMDC_H__CA1D3541_7235_11D1_ABBA_00A0243D1382__INCLUDED_

    #if _MSC_VER >= 1000
        #pragma once
    #endif // _MSC_VER >= 1000

/**$F
// MemDC.h : header file
//

//////////////////////////////////////////////////
// CMemDC - memory DC
//
// Author: Keith Rule
// Email:  keithr@europa.com
// Copyright 1996-1997, Keith Rule
//
// You may freely use or modify this code provided this
// Copyright is included in all derived versions.
//
// History - 10/3/97 Fixed scrolling bug.
//                   Added print support.
//           25 feb 98 - fixed minor assertion bug
//
// This class implements a memory Device Context
*/
class CMemDC :
    public CDC
{
public:

    // constructor sets up the memory DC
    CMemDC(CDC *pDC) :
    CDC()
    {
        ASSERT(pDC != NULL);

        m_pDC = pDC;
        m_pOldBitmap = NULL;
        m_bMemDC = !pDC->IsPrinting();

        if (m_bMemDC)       // Create a Memory DC
        {
            pDC->GetClipBox(&m_rect);
            CreateCompatibleDC(pDC);
            m_bitmap.CreateCompatibleBitmap(pDC, m_rect.Width(), m_rect.Height());
            m_pOldBitmap = SelectObject(&m_bitmap);
            SetWindowOrg(m_rect.left, m_rect.top);
        }
        else                // Make a copy of the relevent parts of the current DC for printing
        {
            m_bPrinting = pDC->m_bPrinting;
            m_hDC = pDC->m_hDC;
            m_hAttribDC = pDC->m_hAttribDC;
        }
    }

    // Destructor copies the contents of the mem DC to the original DC
    ~CMemDC()
    {
        if (m_bMemDC)
        {
            // Copy the offscreen bitmap onto the screen.
            m_pDC->BitBlt(m_rect.left, m_rect.top, m_rect.Width(), m_rect.Height(), this, m_rect.left, m_rect.top,
                          SRCCOPY);

            // Swap back the original bitmap.
            SelectObject(m_pOldBitmap);
        }
        else
        {
            // All we need to do is replace the DC with an illegal value, this keeps us from
            // accidently deleting the handles associated with the CDC that was passed to the
            // constructor.
            m_hDC = m_hAttribDC = NULL;
        }
    }

    // Allow usage as a pointer
    CMemDC *operator->()
    {
        return this;
    }

    // Allow usage as a pointer
    operator CMemDC * ()
    {
        return this;
    }
private:
    CBitmap m_bitmap;       // Offscreen bitmap
    CBitmap *m_pOldBitmap;  // bitmap originally found in CMemDC
    CDC     *m_pDC;         // Saves CDC passed in constructor
    CRect   m_rect;         // Rectangle of drawing area.
    BOOL    m_bMemDC;       // TRUE if CDC really is a Memory DC.
};
//{{AFX_INSERT_LOCATION}}
// Microsoft Developer Studio will insert additional declarations immediately
// before the previous line.
#endif // !defined(AFX_MEMDC_H__CA1D3541_7235_11D1_ABBA_00A0243D1382__INCLUDED_)