dibitmap.cpp

磁盘容量扫描、但界面和程序结构非常不错

		delete m_pPal;
	m_pPal = 0;
	ASSERT( m_pInfo );
	// We only need a palette, if there are <= 256 colors.
	// otherwise we would bomb the memory.
	if( m_pInfo->bmiHeader.biBitCount <= 8 )
		m_pPal = new CBmpPalette(this);
	return m_pPal ? TRUE : FALSE;
}

void CDIBitmap :: ClearPalette() {
	if( m_pPal )
		delete m_pPal;
	m_pPal = 0;
}

void CDIBitmap :: DrawDIB( CDC* pDC, int x, int y ) {
	DrawDIB( pDC, x, y, GetWidth(), GetHeight() );
}

//
// DrawDib uses StretchDIBits to display the bitmap.
void CDIBitmap :: DrawDIB( CDC* pDC, int x, int y, int width, int height ) {
    ASSERT( pDC );
    HDC     hdc = pDC->GetSafeHdc();

	CPalette * pOldPal = 0;

	if( m_pPal ) {
		pOldPal = pDC->SelectPalette( m_pPal, FALSE );
		pDC->RealizePalette();
		// Make sure to use the stretching mode best for color pictures
		pDC->SetStretchBltMode(COLORONCOLOR);
	}

    if( m_pInfo )
        StretchDIBits( hdc,
                       x,
                       y,
                       width,
                       height,
                       0,
                       0,
                       GetWidth(),
                       GetHeight(),
                       GetPixelPtr(),
                       GetHeaderPtr(),
                       DIB_RGB_COLORS,
                       SRCCOPY );
	
	if( m_pPal )
		pDC->SelectPalette( pOldPal, FALSE );
}

int CDIBitmap :: DrawDIB( CDC * pDC, CRect & rectDC, CRect & rectDIB ) {
    ASSERT( pDC );
    HDC     hdc = pDC->GetSafeHdc();

	CPalette * pOldPal = 0;

	if( m_pPal ) {
		pOldPal = pDC->SelectPalette( m_pPal, FALSE );
		pDC->RealizePalette();
		// Make sure to use the stretching mode best for color pictures
		pDC->SetStretchBltMode(COLORONCOLOR);
	}

	int nRet = 0;

    if( m_pInfo )
		nRet =	SetDIBitsToDevice(
					hdc,					// device
					rectDC.left,			// DestX
					rectDC.top,				// DestY
					rectDC.Width(),			// DestWidth
					rectDC.Height(),		// DestHeight
					rectDIB.left,			// SrcX
					rectDIB.top,			// SrcY
					0,						// StartScan
					GetHeight(),			// NumScans
					GetPixelPtr(),			// color data
					GetHeaderPtr(),			// header data
					DIB_RGB_COLORS			// color usage
				);
	
	if( m_pPal )
		pDC->SelectPalette( pOldPal, FALSE );

	return nRet;
}

void	CDIBitmap :: FillDIB( CDC * pDC, CRect rc)
{
	ASSERT( pDC );
    HDC     hdc = pDC->GetSafeHdc();

	CPalette * pOldPal = 0;

	if( m_pPal ) {
		pOldPal = pDC->SelectPalette( m_pPal, FALSE );
		pDC->RealizePalette();
		// Make sure to use the stretching mode best for color pictures
		//pDC->SetStretchBltMode(COLORONCOLOR);
	}

	/*CBrush br;
	br.CreateDIBPatternBrush(GetHeaderPtr(), DIB_RGB_COLORS);
	pDC->FillRect(&rc, &br);*/

	if( m_pInfo )
	{
		// tile the bitmap
		int x=rc.left, y=rc.top;
		int h = rc.bottom;
		int w = rc.right;
		int wBmp = GetWidth();
		int hBmp = GetHeight();
		int wPart = (rc.Width()+wBmp) % wBmp;
		int hPart = (rc.Height()+hBmp) % hBmp;
		int wCur, hCur;

		BYTE* pPtr = GetPixelPtr();
		BITMAPINFO* pHeader = GetHeaderPtr();
	
		while(y < h) 
		{
			hCur = (y + hBmp <= h)? hBmp : hPart;

			x = rc.left;
				
			while(x < w) 
			{
				wCur = (x + wBmp <= w)? wBmp : wPart;

				StretchDIBits( hdc,
					x, y, wCur, hCur,
					0, 0, wCur, hCur,
					pPtr, pHeader, DIB_RGB_COLORS, SRCCOPY );
				x += wCur;
				
			}
			
			y += hCur;
		}
	}
    
	if( m_pPal )
		pDC->SelectPalette( pOldPal, FALSE );
}

BITMAPINFO * CDIBitmap :: GetHeaderPtr() const {
    ASSERT( m_pInfo );
    ASSERT( m_pPixels );
    return m_pInfo;
}

RGBQUAD * CDIBitmap :: GetColorTablePtr() const {
    ASSERT( m_pInfo );
    ASSERT( m_pPixels );
    RGBQUAD* pColorTable = 0;
    if( m_pInfo != 0 ) {
        int cOffset = sizeof(BITMAPINFOHEADER);
        pColorTable = (RGBQUAD*)(((BYTE*)(m_pInfo)) + cOffset);
    }
    return pColorTable;
}

BYTE * CDIBitmap :: GetPixelPtr() const {
    ASSERT( m_pInfo );
    ASSERT( m_pPixels );
    return m_pPixels;
}

int CDIBitmap :: GetWidth() const {
    ASSERT( m_pInfo );
    return m_pInfo->bmiHeader.biWidth;
}

int CDIBitmap :: GetHeight() const {
    ASSERT( m_pInfo );
    return m_pInfo->bmiHeader.biHeight;
}

WORD CDIBitmap :: GetColorCount() const {
	ASSERT( m_pInfo );

	switch( m_pInfo->bmiHeader.biBitCount )	{
		case 1:		return 2;
		case 4:		return 16;
		case 8:		return 256;
		default:	return 0;
	}
}

int CDIBitmap :: GetPalEntries() const {
    ASSERT( m_pInfo );
    return GetPalEntries( *(BITMAPINFOHEADER*)m_pInfo );
}

int CDIBitmap :: GetPalEntries( BITMAPINFOHEADER& infoHeader ) const {
	int nReturn;
	if( infoHeader.biClrUsed == 0 )
		nReturn = ( 1 << infoHeader.biBitCount );
	else
		nReturn = infoHeader.biClrUsed;

	return nReturn;
}

DWORD CDIBitmap :: GetBitsPerPixel() const {
	ASSERT( m_pInfo );
	return m_pInfo->bmiHeader.biBitCount;
}

DWORD CDIBitmap :: LastByte( DWORD dwBitsPerPixel, DWORD dwPixels ) const {
	register DWORD dwBits = dwBitsPerPixel * dwPixels;
	register DWORD numBytes  = dwBits / 8;
	register DWORD extraBits = dwBits - numBytes * 8;
    return (extraBits % 8) ? numBytes+1 : numBytes;
}


DWORD CDIBitmap :: GetBytesPerLine( DWORD dwBitsPerPixel, DWORD dwWidth ) const {
	DWORD dwBits = dwBitsPerPixel * dwWidth;

	if( (dwBits % 32) == 0 )
		return (dwBits/8);  // already DWORD aligned, no padding needed
	
	DWORD dwPadBits = 32 - (dwBits % 32);
	return (dwBits/8 + dwPadBits/8 + (((dwPadBits % 8) > 0) ? 1 : 0));
}

BOOL CDIBitmap :: PadBits() {
	if( m_bIsPadded )
		return TRUE;

    // dwAdjust used when bits per pixel spreads over more than 1 byte
    DWORD dwAdjust = 1, dwOffset = 0, dwPadOffset=0;
	BOOL bIsOdd = FALSE;
    
	dwPadOffset = GetBytesPerLine(GetBitsPerPixel(), GetWidth());
	dwOffset = LastByte(GetBitsPerPixel(), GetWidth());

	if( dwPadOffset == dwOffset )
		return TRUE;

    BYTE * pTemp = new BYTE [GetWidth()*dwAdjust];
    if( !pTemp ) {
		TRACE1("CDIBitmap::PadBits(): could not allocate row of width %d.\n", GetWidth());
		return FALSE;
	}
    
    // enough space has already been allocated for the bit array to
    // include the padding, so we just need to shift rows around.
    // This will pad each "row" on a DWORD alignment.

    for( DWORD row = GetHeight()-1 ; row>0 ; --row ) {
	    CopyMemory((void *)pTemp, (const void *)(m_pPixels + (row*dwOffset)), dwOffset );
	    CopyMemory((void *)(m_pPixels + (row*dwPadOffset)), (const void *)pTemp, dwOffset);
	}
    delete [] pTemp;
    
    return TRUE;
}

BOOL CDIBitmap::UnPadBits() {
	if( ! m_bIsPadded )
		return TRUE;

	DWORD dwAdjust = 1;
	BOOL bIsOdd = FALSE;

	DWORD dwPadOffset = GetBytesPerLine(GetBitsPerPixel(), GetWidth());
	DWORD dwOffset = LastByte(GetBitsPerPixel(), GetWidth());

    BYTE * pTemp = new BYTE [dwOffset];
    if( !pTemp ) {
		TRACE1("CDIBitmap::UnPadBits() could not allocate row of width %d.\n", GetWidth());
		return FALSE;
	}

    // enough space has already been allocated for the bit array to
    // include the padding, so we just need to shift rows around.
    for( DWORD row=1 ; row < DWORD(GetHeight()); ++row ) {
		CopyMemory((void *)pTemp, (const void *)(m_pPixels + row*(dwPadOffset)), dwOffset);
	    CopyMemory((void *)(m_pPixels + (row*dwOffset)), (const void *)pTemp, dwOffset);
	}

    delete [] pTemp;
    
    return TRUE;
}