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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 
// 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; 
#ifndef _WIN32_WCE_NO_PRINTING 
        m_bMemDC = !pDC->IsPrinting(); 
#else 
        m_bMemDC = FALSE; 
#endif 
 
        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); 
#ifndef _WIN32_WCE 
            SetWindowOrg(m_rect.left, m_rect.top); 
#endif 
            // EFW - Bug fix - Fill background in case the user has overridden 
            // WM_ERASEBKGND.  We end up with garbage otherwise. 
            // CJM - moved to fix a bug in the fix. 
            FillSolidRect(m_rect, pDC->GetBkColor()); 
        } 
        else        // Make a copy of the relevent parts of the current DC for printing 
        { 
#if !defined(_WIN32_WCE) || ((_WIN32_WCE > 201) && !defined(_WIN32_WCE_NO_PRINTING)) 
            m_bPrinting = pDC->m_bPrinting; 
#endif 
            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_)