bitmapex.cpp

包括了一些VC编程实例

// BitmapEx.cpp: implementation of the CBitmapEx class.
//
//	History:
//	2002.11.23
//				copy from kdphoto projects
//
//
//	
//	
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "BitmapEx.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif

const int HIMETRIC_INCH	= 2540;

// TransparentBlt	- Copies a bitmap transparently onto the destination DC
// hdcDest		- Handle to destination device context 
// nXDest		- x-coordinate of destination rectangle's upper-left corner 
// nYDest		- y-coordinate of destination rectangle's upper-left corner 
// nWidth		- Width of destination rectangle 
// nHeight		- height of destination rectangle 
// hBitmap		- Handle of the source bitmap
// nXSrc		- x-coordinate of source rectangle's upper-left corner 
// nYSrc		- y-coordinate of source rectangle's upper-left corner 
// colorTransparent	- The transparent color
// hPal			- Logical palette to be used with bitmap. Can be NULL

void MyTransparentBlt( HDC hdcDest, int nXDest, int nYDest, int nWidth, 
					int nHeight, HBITMAP hBitmap, int nXSrc, int nYSrc,
					COLORREF colorTransparent, HPALETTE hPal )
{
	CDC dc, memDC, maskDC, tempDC;
	dc.Attach( hdcDest );
	maskDC.CreateCompatibleDC(&dc);
	CBitmap maskBitmap;
	
	//add these to store return of SelectObject() calls
	CBitmap* pOldMemBmp = NULL;
	CBitmap* pOldMaskBmp = NULL;
	HBITMAP hOldTempBmp = NULL;
	
	memDC.CreateCompatibleDC(&dc);
	tempDC.CreateCompatibleDC(&dc);
	CBitmap bmpImage;
	bmpImage.CreateCompatibleBitmap( &dc, nWidth, nHeight );
	pOldMemBmp = memDC.SelectObject( &bmpImage );
	
	// Select and realize the palette
	if( dc.GetDeviceCaps(RASTERCAPS) & RC_PALETTE && hPal )
	{
		::SelectPalette( dc, hPal, FALSE );
		dc.RealizePalette();
		
		::SelectPalette( memDC, hPal, FALSE );
	}
	
	hOldTempBmp = (HBITMAP) ::SelectObject( tempDC.m_hDC, hBitmap );
	
	memDC.BitBlt( 0,0,nWidth, nHeight, &tempDC, nXSrc, nYSrc, SRCCOPY );
	
	// Create monochrome bitmap for the mask
	maskBitmap.CreateBitmap( nWidth, nHeight, 1, 1, NULL );
	pOldMaskBmp = maskDC.SelectObject( &maskBitmap );
	memDC.SetBkColor( colorTransparent );
	
	// Create the mask from the memory DC
	maskDC.BitBlt( 0, 0, nWidth, nHeight, &memDC, 
		0, 0, SRCCOPY );
	
	// Set the background in memDC to black. Using SRCPAINT with black 
	// and any other color results in the other color, thus making 
	// black the transparent color
	memDC.SetBkColor(RGB(0,0,0));
	memDC.SetTextColor(RGB(255,255,255));
	memDC.BitBlt(0, 0, nWidth, nHeight, &maskDC, 0, 0, SRCAND);
	
	// Set the foreground to black. See comment above.
	dc.SetBkColor(RGB(255,255,255));
	dc.SetTextColor(RGB(0,0,0));
	dc.BitBlt(nXDest, nYDest, nWidth, nHeight, &maskDC, 0, 0, SRCAND);
	
	// Combine the foreground with the background
	dc.BitBlt(nXDest, nYDest, nWidth, nHeight, &memDC, 
		0, 0, SRCPAINT);
	
	
	if (hOldTempBmp)
		::SelectObject( tempDC.m_hDC, hOldTempBmp);
	if (pOldMaskBmp)
		maskDC.SelectObject( pOldMaskBmp );
	if (pOldMemBmp)
		memDC.SelectObject( pOldMemBmp );
	
	dc.Detach();
}


//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

CBitmapEx::CBitmapEx()
{

}

CBitmapEx::~CBitmapEx()
{

}

BOOL CBitmapEx::StretchDraw(CDC *pDC, LPRECT r, LPRECT sr )
{
	if ( !r ) return FALSE;
	CDC dc;
	dc.CreateCompatibleDC( pDC );
	CBitmap * bmp = dc.SelectObject( this );
	pDC->SetStretchBltMode(COLORONCOLOR);
	if ( !sr )
		pDC->StretchBlt( r->left, r->top, r->right, r->bottom, &dc, 0, 0, GetWidth(), GetHeight() ,
			SRCCOPY );
	else
		pDC->StretchBlt( r->left, r->top, r->right - r->left, r->bottom - r->top, &dc, sr->left, sr->top, 
		sr->right - sr->left, sr->bottom - sr->top,
			SRCCOPY );

	
	dc.SelectObject( bmp );	
	return TRUE;	

}

BOOL CBitmapEx::StretchDraw(CDC *pDC, LPRECT r)
{
	CDC dc;
	dc.CreateCompatibleDC( pDC );
	CBitmap * bmp = dc.SelectObject( this );
	
	pDC->StretchBlt( r->left, r->top, r->right, r->bottom, &dc, 0, 0, GetWidth(), GetHeight() ,
		SRCCOPY );
	
	dc.SelectObject( bmp );	
	return TRUE;	
}

BOOL CBitmapEx::Draw( CDC *pDC, int x, int y, LPRECT sr, COLORREF colTrans, BOOL bTrans )
{
	if ( !bTrans )
		Draw( pDC ,x, y, sr );
	else
	{
		MyTransparentBlt( pDC->GetSafeHdc(), x, y, sr->right - sr->left, sr->bottom - sr->top, 
			(HBITMAP)this->GetSafeHandle(), sr->left, sr->top, colTrans, NULL );
	}
	return TRUE;
}

//draw sub bmp to special point
BOOL CBitmapEx::Draw( CDC *pDC, int x, int y, LPRECT sr )
{
	CDC dc;
	dc.CreateCompatibleDC( pDC );
	CBitmap * bmp = dc.SelectObject( this );	
	if ( sr != NULL)
		pDC->BitBlt( x, y, sr->right - sr->left, sr->bottom - sr->top, &dc, 
			sr->left, sr->top,  SRCCOPY );
	else
		pDC->BitBlt( x, y, Width(), Height(), &dc, 
			0, 0,  SRCCOPY );
	dc.SelectObject( bmp );		
	return TRUE;

}

BOOL CBitmapEx::Draw(CDC *pDC, LPRECT r)
{
	CDC dc;
	dc.CreateCompatibleDC( pDC );
	CBitmap * bmp = dc.SelectObject( this );	
	pDC->BitBlt( r->left, r->top, r->right - r->left, r->bottom - r->top, &dc, 0, 0 ,
		  SRCCOPY );

	dc.SelectObject( bmp );		
	return TRUE;
}


///HOWTO: Drawing Transparent Bitmaps
//see: Microsoft Knowledge Base Article - Q79212
BOOL CBitmapEx::DrawTransparent(CDC * pDC, int x, int y, COLORREF crColour)
{
	MyTransparentBlt( pDC->GetSafeHdc(), x, y, GetWidth(), GetHeight(), (HBITMAP)this->GetSafeHandle(), 0, 0, crColour, NULL );
/*
	COLORREF crOldBack = pDC->SetBkColor(0);
	COLORREF crOldText = pDC->SetTextColor(RGB(255,255,255));
	CDC dcImage, dcTrans;
	
	// Create two memory dcs for the image and the mask
	dcImage.CreateCompatibleDC(pDC);
	dcTrans.CreateCompatibleDC(pDC);
	
	// Select the image into the appropriate dc
	CBitmap* pOldBitmapImage = dcImage.SelectObject(this);
	
	// Create the mask bitmap
	CBitmap bitmapTrans;
	int nWidth = GetWidth();
	int nHeight = GetHeight();
	bitmapTrans.CreateBitmap(nWidth, nHeight, 1, 1, NULL);
	
	// Select the mask bitmap into the appropriate dc
	CBitmap* pOldBitmapTrans = dcTrans.SelectObject(&bitmapTrans);
	
	// Build mask based on transparent colour
	dcImage.SetBkColor(crColour);
	dcTrans.BitBlt(0, 0, nWidth, nHeight, &dcImage, 0, 0, SRCCOPY);
	
	// Do the work - True Mask method - cool if not actual display
	pDC->BitBlt(x, y, nWidth, nHeight, &dcImage, 0, 0, SRCINVERT);
	pDC->BitBlt(x, y, nWidth, nHeight, &dcTrans, 0, 0, SRCAND);
	pDC->BitBlt(x, y, nWidth, nHeight, &dcImage, 0, 0, SRCINVERT);
	
	// Restore settings
	dcImage.SelectObject(pOldBitmapImage);
	dcTrans.SelectObject(pOldBitmapTrans);
	pDC->SetBkColor(crOldBack);
	pDC->SetTextColor(crOldText);
*/
	return TRUE;
}	


HRGN CBitmapEx::CreateRgnFromFile( COLORREF color )
{
	HBITMAP hBmp = (HBITMAP)this->GetSafeHandle();

	// get image properties
	BITMAP bmp = { 0 };
	::GetObject( hBmp, sizeof(BITMAP), &bmp );
	// allocate memory for extended image information
	LPBITMAPINFO bi = (LPBITMAPINFO) new BYTE[ sizeof(BITMAPINFO) + 8 ];
	memset( bi, 0, sizeof(BITMAPINFO) + 8 );
	bi->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
	// set window size
	int m_dwWidth	= bmp.bmWidth;		// bitmap width
	int m_dwHeight	= bmp.bmHeight;		// bitmap height
	// create temporary dc
	HDC dc = CreateIC( "DISPLAY",NULL,NULL,NULL );
	// get extended information about image (length, compression, length of color table if exist, ...)
	DWORD res = GetDIBits( dc, hBmp, 0, bmp.bmHeight, 0, bi, DIB_RGB_COLORS );
	// allocate memory for image data (colors)
	LPBYTE pBits = new BYTE[ bi->bmiHeader.biSizeImage + 4 ];
	// allocate memory for color table
	if ( bi->bmiHeader.biBitCount == 8 )
	{
		// actually color table should be appended to this header(BITMAPINFO),
		// so we have to reallocate and copy it
		LPBITMAPINFO old_bi = bi;
		// 255 - because there is one in BITMAPINFOHEADER
		bi = (LPBITMAPINFO)new char[ sizeof(BITMAPINFO) + 255 * sizeof(RGBQUAD) ];
		memcpy( bi, old_bi, sizeof(BITMAPINFO) );
		// release old header
		delete old_bi;
	}
	// get bitmap info header
	BITMAPINFOHEADER& bih = bi->bmiHeader;
	// get color table (for 256 color mode contains 256 entries of RGBQUAD(=DWORD))
	LPDWORD clr_tbl = (LPDWORD)&bi->bmiColors;
	// fill bits buffer
	res = GetDIBits( dc, hBmp, 0, bih.biHeight, pBits, bi, DIB_RGB_COLORS );
	DeleteDC( dc );

	BITMAP bm;
	::GetObject( hBmp, sizeof(BITMAP), &bm );
	// shift bits and byte per pixel (for comparing colors)
	LPBYTE pClr = (LPBYTE)&color;
	// swap red and blue components
	BYTE tmp = pClr[0]; pClr[0] = pClr[2]; pClr[2] = tmp;
	// convert color if curent DC is 16-bit (5:6:5) or 15-bit (5:5:5)
	if ( bih.biBitCount == 16 )
	{
		// for 16 bit
		color = ((DWORD)(pClr[0] & 0xf8) >> 3) |
				((DWORD)(pClr[1] & 0xfc) << 3) |
				((DWORD)(pClr[2] & 0xf8) << 8);
		// for 15 bit
//		color = ((DWORD)(pClr[0] & 0xf8) >> 3) |
//				((DWORD)(pClr[1] & 0xf8) << 2) |
//				((DWORD)(pClr[2] & 0xf8) << 7);
	}

	const DWORD RGNDATAHEADER_SIZE	= sizeof(RGNDATAHEADER);
	const DWORD ADD_RECTS_COUNT		= 40;			// number of rects to be appended
													// to region data buffer

	// BitPerPixel
	BYTE	Bpp = bih.biBitCount >> 3;				// bytes per pixel
	// bytes per line in pBits is DWORD aligned and bmp.bmWidthBytes is WORD aligned
	// so, both of them not