www.pudn.com > commspy.rar > util_mdc.cpp

 
// util_medc.cpp 
 
#include "stdafx.h" 
#include "util_mdc.h" 
 
 
 
 
 
GMemDC::GMemDC() : pOldBitmap(NULL), bPaintStructInitialized(FALSE) 
{ 
} 
 
GMemDC::~GMemDC() 
{ 
   // check if release was called 
   ASSERT(pOldBitmap == NULL);   
   ASSERT(bPaintStructInitialized == FALSE); 
} 
 
 
 
 
BOOL GMemDC::Create(CDC *pDC, const RECT& rDest, CBrush *pBkBrush, const PAINTSTRUCT *pPS) 
{ 
   BOOL bOK = FALSE; 
   pOldBitmap = NULL; 
 
   ASSERT(pDC != NULL); 
   ASSERT(m_hDC == NULL); 
    
   if(pDC != NULL) 
   { 
      if(CreateCompatibleDC(pDC) != 0)  
      { 
         CRect rDestRect(rDest); 
 
      #ifdef _MFC_DOCS_HAVE_NO_ERRORS_ 
         int iBitsPerPixel = pDC->GetDeviceCaps(BITSPIXEL); 
 
      #ifdef _DEBUG    
         int iThisBitsPerPixel = GetDeviceCaps(BITSPIXEL); 
         // these should be the same 
         ASSERT(iThisBitsPerPixel == iBitsPerPixel); 
      #endif 
 
         // The documentation for CreateCompatibleBitmap() says the  
         // height and width parameters are in 'bits', not pixels. 
         // Our experience with this functions says otherwise. 
         int iWidth = rDestRect.Width() * iBitsPerPixel;  
         int iHeight = rDestRect.Height() * iBitsPerPixel;  
       
         CSize sizeBitmap(iWidth, iHeight); 
      #endif 
 
         CSize sizeBitmap(rDestRect.Width(), rDestRect.Height()); 
 
         // create an uninitialized bitmap 
         if(Bitmap.CreateCompatibleBitmap(pDC, sizeBitmap.cx, sizeBitmap.cy) != 0) 
         { 
	         pOldBitmap = SelectObject(&Bitmap); 
	         if(pOldBitmap != NULL) 
            { 
               CBrush *pBrush = pBkBrush; 
               if(pBrush == NULL) 
                  pBrush = pDC->GetCurrentBrush(); 
 
               ASSERT(pBrush != NULL); 
                
               // initialize background 
               if(pBrush != NULL) 
                  FillRect(rDestRect, pBrush); 
 
               if(pPS != NULL) 
               { 
                  bPaintStructInitialized = TRUE; 
                  memcpy((void *)&m_ps, (void *)pPS, sizeof(m_ps)); 
               } 
 
               bOK = TRUE; 
            } 
         } 
      } 
   } 
 
   ASSERT(bOK == TRUE); 
 
   return bOK; 
} 
 
 
 
 
BOOL GMemDC::Copy(CDC *pDC, const RECT& rDest, const POINT *pptSource) 
{ 
   BOOL bOK = FALSE; 
   CRect r(rDest); 
 
   ASSERT(this != NULL); 
   ASSERT(pDC != NULL); 
   // must be true in order to use BitBlt() 
   ASSERT(pDC->GetDeviceCaps(RASTERCAPS) & RC_BITBLT); 
    
   POINT ptSrcTopLeft; 
   if(pptSource != NULL) 
      ptSrcTopLeft = (*pptSource); 
   else   // default to destination rect upper-left 
   { 
      ptSrcTopLeft.x = r.left; 
      ptSrcTopLeft.y = r.top; 
   } 
 
   if(pDC != NULL) 
      bOK = pDC->BitBlt(r.left, r.top, r.Width(), r.Height(),  
                        this, ptSrcTopLeft.x, ptSrcTopLeft.y, SRCCOPY); 
 
   ASSERT(bOK == TRUE); 
 
   return bOK; 
} 
 
 
 
 
BOOL GMemDC::Release() 
{ 
   BOOL bOK = FALSE; 
 
   ASSERT(pOldBitmap != NULL); 
 
   if(pOldBitmap != NULL) 
   {  
      SelectObject(pOldBitmap); 
      pOldBitmap = NULL; 
      bOK = TRUE;             
   } 
 
   bPaintStructInitialized = FALSE; 
 
   return bOK; 
} 
 
 
 
 
 
const PAINTSTRUCT *GMemDC::GetPaintStruct() const 
{ 
   const PAINTSTRUCT *pPS; 
 
   if(bPaintStructInitialized == TRUE) 
      pPS = (const PAINTSTRUCT *)(&m_ps); 
   else 
      pPS = NULL; 
 
   return pPS; 
}