::DeleteObject(hBitmap);			delete [] lpBMIH;			::SelectPalette(hdc, hOldPalette, FALSE);			return FALSE; 		}		else		{			m_dwSizeImage = lpBMIH->biSizeImage;		}	}	else	{		lpBMIH->biCompression = BI_RGB; // decompress		// figure the image size from the bitmap width and height		DWORD dwBytes = ((DWORD) lpBMIH->biWidth * lpBMIH->biBitCount) / 32;		if(((DWORD) lpBMIH->biWidth * lpBMIH->biBitCount) % 32)		{			dwBytes++;		}		dwBytes *= 4;		m_dwSizeImage = dwBytes * lpBMIH->biHeight; // no compression		lpBMIH->biSizeImage = m_dwSizeImage;	} 	// second GetDIBits call to make DIB	LPBYTE lpImage = (LPBYTE) new char[m_dwSizeImage];	VERIFY(::GetDIBits(pDC->GetSafeHdc(), hBitmap, 0, (UINT) lpBMIH->biHeight,    		lpImage, (LPBITMAPINFO) lpBMIH, DIB_RGB_COLORS));    TRACE("dib successfully created - height = %d\n", lpBMIH->biHeight);	::DeleteObject(hBitmap);	Empty();	m_nBmihAlloc = m_nImageAlloc = crtAlloc;	m_lpBMIH = lpBMIH;	m_lpImage = lpImage;	ComputeMetrics();	ComputePaletteSize(m_lpBMIH->biBitCount);	MakePalette();	::SelectPalette(hdc, hOldPalette, FALSE);	TRACE("Compress: new palette size = %d\n", m_nColorTableEntries); 	return TRUE;}BOOL CDib::Read(CFile* pFile){	// 1. read file header to get size of info hdr + color table	// 2. read info hdr (to get image size) and color table	// 3. read image	// can't use bfSize in file header		// 清除DIB	Empty();		int nCount, nSize;	BITMAPFILEHEADER bmfh;		// 嘗試讀取BMP文件	try	{		// 讀BMP文件頭		nCount = pFile->Read((LPVOID) &bmfh, sizeof(BITMAPFILEHEADER));				// 判斷讀取文件頭的大小是否		if(nCount != sizeof(BITMAPFILEHEADER))		{			// 讀文件出錯			throw new CException;		}				// 判斷是否是"BM"		if(bmfh.bfType != 0x4d42)		{			// 不是BMP文件，拋出異常			throw new CException;		}		nSize = bmfh.bfOffBits - sizeof(BITMAPFILEHEADER);		m_lpBMIH = (LPBITMAPINFOHEADER) new char[nSize];		m_nBmihAlloc = m_nImageAlloc = crtAlloc;		nCount = pFile->Read(m_lpBMIH, nSize); // info hdr & color table		ComputeMetrics();		ComputePaletteSize(m_lpBMIH->biBitCount);		MakePalette();		m_lpImage = (LPBYTE) new char[m_dwSizeImage];		nCount = pFile->Read(m_lpImage, m_dwSizeImage); // image only	}	catch(CException* pe)	{		AfxMessageBox("Read error");		pe->Delete();		return FALSE;	}	return TRUE;}BOOL CDib::ReadSection(CFile* pFile, CDC* pDC /* = NULL */){	// new function reads BMP from disk and creates a DIB section	//    allows modification of bitmaps from disk	// 1. read file header to get size of info hdr + color table	// 2. read info hdr (to get image size) and color table	// 3. create DIB section based on header parms	// 4. read image into memory that CreateDibSection allocates	Empty();	int nCount, nSize;	BITMAPFILEHEADER bmfh;	try	{		nCount = pFile->Read((LPVOID) &bmfh, sizeof(BITMAPFILEHEADER));		if(nCount != sizeof(BITMAPFILEHEADER))		{			throw new CException;		}		if(bmfh.bfType != 0x4d42)		{			throw new CException;		}		nSize = bmfh.bfOffBits - sizeof(BITMAPFILEHEADER);		m_lpBMIH = (LPBITMAPINFOHEADER) new char[nSize];		m_nBmihAlloc = crtAlloc;		m_nImageAlloc = noAlloc;		nCount = pFile->Read(m_lpBMIH, nSize); // info hdr & color table		if(m_lpBMIH->biCompression != BI_RGB)		{			throw new CException;		}		ComputeMetrics();		ComputePaletteSize(m_lpBMIH->biBitCount);		MakePalette();		UsePalette(pDC);		m_hBitmap = ::CreateDIBSection(pDC->GetSafeHdc(), (LPBITMAPINFO) m_lpBMIH,			DIB_RGB_COLORS,	(LPVOID*) &m_lpImage, NULL, 0);		ASSERT(m_lpImage != NULL);		nCount = pFile->Read(m_lpImage, m_dwSizeImage); // image only	}	catch(CException* pe)	{		AfxMessageBox("ReadSection error");		pe->Delete();		return FALSE;	}	return TRUE;}BOOL CDib::Write(CFile* pFile){	BITMAPFILEHEADER bmfh;	bmfh.bfType = 0x4d42;  // 'BM'	int nSizeHdr = sizeof(BITMAPINFOHEADER) + sizeof(RGBQUAD) * m_nColorTableEntries;	bmfh.bfSize = 0;	// bmfh.bfSize = sizeof(BITMAPFILEHEADER) + nSizeHdr + m_dwSizeImage;	// meaning of bfSize open to interpretation (bytes, words, dwords?) -- we won't use it	bmfh.bfReserved1 = bmfh.bfReserved2 = 0;	bmfh.bfOffBits = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) +			sizeof(RGBQUAD) * m_nColorTableEntries;		try	{		pFile->Write((LPVOID) &bmfh, sizeof(BITMAPFILEHEADER));		pFile->Write((LPVOID) m_lpBMIH,  nSizeHdr);		pFile->Write((LPVOID) m_lpImage, m_dwSizeImage);	}	catch(CException* pe)	{		pe->Delete();		AfxMessageBox("write error");		return FALSE;	}	return TRUE;}void CDib::Serialize(CArchive& ar){	DWORD dwPos;	dwPos = ar.GetFile()->GetPosition();	TRACE("CDib::Serialize -- pos = %d\n", dwPos);	ar.Flush();	dwPos = ar.GetFile()->GetPosition();	TRACE("CDib::Serialize -- pos = %d\n", dwPos);	if(ar.IsStoring())	{		Write(ar.GetFile());	}	else	{		Read(ar.GetFile());	}}// helper functionsvoid CDib::ComputePaletteSize(int nBitCount){	if((m_lpBMIH == NULL) || (m_lpBMIH->biClrUsed == 0))	{		switch(nBitCount)		{			case 1:				m_nColorTableEntries = 2;				break;			case 4:				m_nColorTableEntries = 16;				break;			case 8:				m_nColorTableEntries = 256;				break;			case 16:			case 24:			case 32:				m_nColorTableEntries = 0;				break;			default:				ASSERT(FALSE);		}	}	else	{		m_nColorTableEntries = m_lpBMIH->biClrUsed;	}	ASSERT((m_nColorTableEntries >= 0) && (m_nColorTableEntries <= 256)); }void CDib::ComputeMetrics(){	if(m_lpBMIH->biSize != sizeof(BITMAPINFOHEADER))	{		TRACE("Not a valid Windows bitmap -- probably an OS/2 bitmap\n");		throw new CException;	}	m_dwSizeImage = m_lpBMIH->biSizeImage;	if(m_dwSizeImage == 0)	{		DWORD dwBytes = ((DWORD) m_lpBMIH->biWidth * m_lpBMIH->biBitCount) / 32;		if(((DWORD) m_lpBMIH->biWidth * m_lpBMIH->biBitCount) % 32)		{			dwBytes++;		}		dwBytes *= 4;		m_dwSizeImage = dwBytes * m_lpBMIH->biHeight; // no compression	}	m_lpvColorTable = (LPBYTE) m_lpBMIH + sizeof(BITMAPINFOHEADER);}void CDib::Empty(){	// this is supposed to clean up whatever is in the DIB	DetachMapFile();	if(m_nBmihAlloc == crtAlloc)	{		delete [] m_lpBMIH;	}	else if(m_nBmihAlloc == heapAlloc)	{		::GlobalUnlock(m_hGlobal);		::GlobalFree(m_hGlobal);	}	if(m_nImageAlloc == crtAlloc)	{		delete [] m_lpImage;	}	if(m_hPalette != NULL)	{		::DeleteObject(m_hPalette);	}	if(m_hBitmap != NULL)	{		::DeleteObject(m_hBitmap);	}	m_nBmihAlloc = m_nImageAlloc = noAlloc;	m_hGlobal = NULL;	m_lpBMIH = NULL;	m_lpImage = NULL;	m_lpvColorTable = NULL;	m_nColorTableEntries = 0;	m_dwSizeImage = 0;	m_lpvFile = NULL;	m_hMap = NULL;	m_hFile = NULL;	m_hBitmap = NULL;	m_hPalette = NULL;}void CDib::DetachMapFile(){	if(m_hFile == NULL)	{		return;	}	::UnmapViewOfFile(m_lpvFile);	::CloseHandle(m_hMap);	::CloseHandle(m_hFile);	m_hFile = NULL;}