voimage.cpp

Windows CE下操作、显示图像的类。可以打开、显示png、gif、jpg等系统支持的格式。

	return TRUE;
}

BOOL CVOImage::DrawTransparent(HDC hdc,
							   int x,
							   int y,
							   int cx,
							   int cy,
							   COLORREF crTransparent)
{
	if ( -1 == cx )
	{
		cx = GetWidth();
	}
	if ( -1 == cy )
	{
		cy = GetHeight();
	}

	if (crTransparent == RGB(192, 192, 192))
	{
		crTransparent = GetPixel(0, 0);	// If none of the above conditions are met, use the pixel at 0,0 (Uppler Left)
	}

#ifdef _WIN32_WCE
	return ::TransparentImage(hdc,
							  x,
							  y,
							  cx,
							  cy,
							  m_hDC,
							  0,
							  0,
							  GetWidth(),
							  GetHeight(),
							  crTransparent);
#else
	return FALSE;
#endif
}

DWORD CVOImage::GetHeight() const
{
	return m_dwHeight;
}

DWORD CVOImage::GetWidth() const
{
	return m_dwWidth;
}

WORD CVOImage::GetPlanes() const
{
	return m_wPlanes;
}

WORD CVOImage::GetBitsPixel() const
{
	return m_wBitsPixel;
}

BOOL CVOImage::SetBitmap(HDC hdc,
						 DWORD dwResourceID,
						 LPCTSTR pcszClass,
						 HMODULE hModule)
{
	if ( NULL != m_hBitmap )
	{
		if (m_hModuleResource == hModule && m_dwResourceID == dwResourceID)
		{
			return TRUE;	// Already loaded
		}

		::DeleteObject(m_hBitmap);
	}

	if ( NULL == m_hDC )
	{
		m_hDC = ::CreateCompatibleDC(hdc);

		HBITMAP	hbitmap = ::CreateCompatibleBitmap(hdc,
						  ::GetDeviceCaps(hdc, HORZRES),
						  ::GetDeviceCaps(hdc, VERTRES));

		::SelectObject(m_hDC, hbitmap);
	}

	BYTE    szBuffer[1024] = {0};

#ifdef _WIN32_WCE
	HRESULT hr;

	DecompressImageInfo	dii;
#endif

	if (hModule == 0)
	{
		hModule = ::GetModuleHandle(NULL);
	}

	CVOResource	res(hModule, dwResourceID, pcszClass);

	if ( !res.IsLoaded() )
	{
		return FALSE;
	}

	res.SetUserData(0);	// Use this for the current resource offset

#ifdef _WIN32_WCE
	// Fill in the 'DecompressImageInfo' structure
	dii.dwSize = sizeof( DecompressImageInfo );		// Size of this structure
	dii.pbBuffer = szBuffer;						// Pointer to the buffer to use for data
	dii.dwBufferMax = 1024;							// Size of the buffer
	dii.dwBufferCurrent = 0;						// The amount of data which is current in the buffer
	dii.phBM = &m_hBitmap;							// Pointer to the bitmap returned (can be NULL)
	dii.ppImageRender = NULL;						// Pointer to an IImageRender object (can be NULL)
	dii.iBitDepth = GetDeviceCaps(hdc, BITSPIXEL);	// Bit depth of the output image
	dii.lParam = ( LPARAM ) & res;					// User parameter for callback functions
	dii.hdc = m_hDC;								// HDC to use for retrieving palettes
	dii.iScale = g_iScale;							// Scale factor (1 - 100)
	dii.iMaxWidth = g_iMaxWidth;					// Maximum width of the output image
	dii.iMaxHeight = g_iMaxHeight;					// Maximum height of the output image
	dii.pfnGetData = GetImageResourceData;			// Callback function to get image data
	dii.pfnImageProgress = ImageProgress;			// Callback function to notify caller of progress decoding the image
	dii.crTransparentOverride = ( UINT ) - 1;		// If this color is not (UINT)-1, it will override the
	// transparent color in the image with this color. (GIF ONLY)
	// Process and decompress the image data
	hr = ::DecompressImageIndirect( &dii );
#endif

	HBITMAP hbitmapOld = (HBITMAP)::SelectObject(m_hDC, m_hBitmap);

	::DeleteObject(hbitmapOld);

	BITMAP	bmp;

	::GetObject(m_hBitmap, sizeof(BITMAP), &bmp);

	m_dwWidth		= bmp.bmWidth;
	m_dwHeight		= bmp.bmHeight;
	m_wPlanes		= bmp.bmPlanes;
	m_wBitsPixel	= bmp.bmBitsPixel;

	m_strFileName.Empty();
	m_hModuleResource	= hModule;
	m_dwResourceID		= dwResourceID;

	return TRUE;
}

DWORD CALLBACK CVOImage::GetImageData(LPSTR szBuffer,
									  DWORD dwBufferMax,
									  LPARAM lParam)
{
	DWORD dwNumberOfBytesRead;

	if ( (HANDLE)lParam == INVALID_HANDLE_VALUE )
	{
		return 0;
	}

	::ReadFile((HANDLE)lParam,
			   szBuffer,
			   dwBufferMax,
			   &dwNumberOfBytesRead,
			   NULL);

	// Return number of bytes read
	return dwNumberOfBytesRead;
}

DWORD CALLBACK CVOImage::GetImageResourceData(LPSTR szBuffer,
		DWORD dwBufferMax,
		LPARAM lParam)
{
	DWORD			dwNumberOfBytesToRead	= dwBufferMax;
	CVOResource*	pRes					= (CVOResource*)lParam;

	if ( NULL == pRes )
	{
		return 0;
	}

	DWORD dwResourceOffset = pRes->GetUserData();

	if ( dwResourceOffset + dwNumberOfBytesToRead > pRes->GetSize() )
	{
		dwNumberOfBytesToRead = pRes->GetSize() - dwResourceOffset;
	}

	::memmove(szBuffer,
			  pRes->GetData() + dwResourceOffset,
			  dwNumberOfBytesToRead);

	pRes->SetUserData(dwResourceOffset + dwNumberOfBytesToRead);

	return dwNumberOfBytesToRead;	// return amount read
}

#ifdef _WIN32_WCE
void CALLBACK CVOImage::ImageProgress(IImageRender* /*pRender*/,
									  BOOL bComplete,
									  LPARAM /*lParam*/)
{
	if ( bComplete )
	{
		;// (Optional) add code here for completion processing
	}
}
#endif

BOOL CVOImage::IsLoaded() const
{
	return ( NULL != m_hBitmap );
}

CVOResource::CVOResource(HMODULE hModule,
						 DWORD dwResourceID,
						 LPCTSTR pcszClass)
{
	m_dwSize	= 0;
	m_hGlobal	= 0;
	m_pData		= 0;

	m_hrsrc		= ::FindResource(hModule, (LPCTSTR)dwResourceID, pcszClass);

	if ( NULL == m_hrsrc )
	{
		return;
	}

	m_dwSize	= ::SizeofResource(hModule, m_hrsrc);
	m_hGlobal	= ::LoadResource(hModule, m_hrsrc);
	m_pData		= (PBYTE)(::LockResource(m_hGlobal));
}

CVOResource::~CVOResource()
{
	if ( NULL != m_hGlobal )
	{
		::DeleteObject(m_hGlobal);
	}
}

DWORD CVOResource::GetSize()
{
	return m_dwSize;
}

PBYTE CVOResource::GetData()
{
	return m_pData;
}

void CVOResource::SetUserData(DWORD dwValue)
{
	m_dwUser = dwValue;
}

DWORD CVOResource::GetUserData()
{
	return m_dwUser;
}

BOOL CVOResource::IsLoaded()
{
	return ( NULL != m_pData );
}

COLORREF CVOImage::GetPixel(int x, int y)
{
	if ( NULL == m_hDC )
	{
		return RGB(0, 0, 0);
	}

	return ::GetPixel(m_hDC, x, y);
}

BOOL CVOImage::SetCanvasSize(int x,
							 int y,
							 COLORREF rgbBackground,
							 BOOL bfHCenter,
							 BOOL bfVCenter)
{
	if ( RGB(1, 1, 1) == rgbBackground )
	{
		rgbBackground = GetPixel(0, 0);
	}

	if ( x < (int)GetWidth() || y < (int)GetHeight() )
	{
		return FALSE;	// Cropping may be implemented at some point in the future
	}

	int nOffsetX = 0;
	int nOffsetY = 0;

	if ( bfHCenter )
	{
		nOffsetX = (x - GetWidth()) / 2;
	}

	if ( bfVCenter )
	{
		nOffsetY = (y - GetHeight()) / 2;
	}

	BITMAP	bm, bmNew;

	::GetObject(m_hBitmap, sizeof(BITMAP), &bm);

	HDC hdc		= ::CreateCompatibleDC(m_hDC);

	HBITMAP hbitmapNew	= ::CreateCompatibleBitmap(m_hDC, x, y);
	::SelectObject(hdc, hbitmapNew);

	RECT rect;

	rect.left = 0;
	rect.top = 0;
	rect.right = x;
	rect.bottom = y;

	::FillRect(hdc, &rect, (HBRUSH)GetStockObject(WHITE_BRUSH));

	if ( !::BitBlt(hdc,
				   nOffsetX,
				   nOffsetY,
				   GetWidth(),
				   GetHeight(),
				   m_hDC,
				   0,
				   0,
				   SRCCOPY) )
	{
		::DeleteDC(hdc);
		::DeleteObject(hbitmapNew);

		return FALSE;
	}

	HBITMAP hPrev = (HBITMAP)::GetObject(hbitmapNew, sizeof(BITMAP), &bmNew);

	::SelectObject(hdc, hPrev);

	::DeleteDC(m_hDC);
	::DeleteObject(m_hBitmap);

	m_hDC		= hdc;
	m_hBitmap	= hbitmapNew;

	return TRUE;
}

CVOImage::operator HBITMAP()
{
	return m_hBitmap;
}

const CVOString& CVOImage::GetFileName() const
{
	return m_strFileName;
}