#define PW_WINDOW 9001
#define PW_CLIENT 9002
HBITMAP CMyProgramDlg::copyScreenToBitmap(LPRECT lpRect)
{
HDC hScrDC,hMemDC; // screen DC and memory DC
int nX,nY,nX2,nY2; // coordinates of rectangle to grab
int nWidth,nHeight; // DIB width and height
int xScrn,yScrn; // screen resolution
HGdioBJ hOldBitmap,hBitmap;
// check for an empty rectangle
if (IsRectEmpty(lpRect))
return NULL;
// create a DC for the screen and create
// a memory DC compatible to screen DC
hScrDC = CreateDC("disPLAY",NULL,NULL);
hMemDC = CreateCompatibleDC(hScrDC); // get points of rectangle to grab
nX = lpRect->left;
nY = lpRect->top;
nX2 = lpRect->right;
nY2 = lpRect->bottom; // get screen resolution
xScrn = GetDeviceCaps(hScrDC,HORZRES);
yScrn = GetDeviceCaps(hScrDC,VERTRES);
//make sure bitmap rectangle is visible
if (nX < 0)
nX = 0;
if (nY < 0)
nY = 0;
if (nX2 > xScrn)
nX2 = xScrn;
if (nY2 > yScrn)
nY2 = yScrn;
nWidth = nX2 - nX;
nHeight = nY2 - nY;
// create a bitmap compatible with the screen DC
hBitmap = CreateCompatibleBitmap(hScrDC,nWidth,nHeight);
// select new bitmap into memory DC
hOldBitmap = SelectObject (hMemDC,hBitmap);
// bitblt screen DC to memory DC
BitBlt(hMemDC,nHeight,hScrDC,nX,SRCcopY);
// select old bitmap back into memory DC and get handle to
// bitmap of the screen
hBitmap = SelectObject(hMemDC,hOldBitmap);
// clean up
DeleteDC(hScrDC);
DeleteDC(hMemDC);
// return handle to the bitmap
return (HBITMAP)hBitmap;
}
HBITMAP CYourProgramDlg::copyWindowToBitmap(CWnd* wnd,HWND hWnd,WORD fPrintArea)
{
HBITMAP hBitmap = NULL; // handle to device-dependent bitmap
// check for a valid window handle
if (!hWnd)
return NULL;
RECT rectWnd;
::GetwindowRect(hWnd,&rectWnd);
switch (fPrintArea)
{
case PW_WINDOW: // copy entire window
{
// get the window rectangle
// get the bitmap of that window by calling
// copyScreenToBitmap and passing it the window rect
// GetwindowRect(&rectWnd);
hBitmap = copyScreenToBitmap(&rectWnd);
break;
}
case PW_CLIENT: // copy client area
{
RECT rectClient;
POINT pt1,pt2; // get client dimensions
wnd->GetClientRect(&rectClient); // convert client coords to screen coords
pt1.x = rectClient.left;
pt1.y = rectClient.top;
pt2.x = rectClient.right;
pt2.y = rectClient.bottom;
wnd->ClientToScreen(&pt1);
wnd->ClientToScreen(&pt2);
rectClient.left = pt1.x;
rectClient.top = pt1.y;
rectClient.right = pt2.x;
rectClient.bottom = pt2.y;
// get the bitmap of the client area by calling
// copyScreenToBitmap and passing it the client rect
hBitmap = copyScreenToBitmap(&rectClient);
break;
}
default: // invalid print area
return NULL;
} // return handle to the bitmap
return hBitmap;
}A good usage is :
Code:
HBITMAP hBitmap = copyWindowToBitmap(this,GetDesktopWindow()->m_hWnd,PW_
1：拷贝屏幕DC成为位图句柄
HBITMAP copyDCToBitmap(HDC hScrDC,LPRECT lpRect)
{
if(hScrDC==NULL || lpRect==NULL || IsRectEmpty(lpRect))
{
return NULL;
}
HDC hMemDC;
// 屏幕和内存设备描述表
HBITMAP hBitmap,hOldBitmap;
// 位图句柄
int nX,nY2;
// 选定区域坐标
int nWidth,nHeight;
// 位图宽度和高度
// 确保选定区域不为空矩形
if (IsRectEmpty(lpRect))
return NULL;
// 获得选定区域坐标
nX = lpRect->left;
nY = lpRect->top;
nX2 = lpRect->right;
nY2 = lpRect->bottom;
nWidth = nX2 - nX;
nHeight = nY2 - nY;
//为指定设备描述表创建兼容的内存设备描述表
hMemDC = CreateCompatibleDC(hScrDC);
// 创建一个与指定设备描述表兼容的位图
hBitmap = CreateCompatibleBitmap(hScrDC,nHeight);
// 把新位图选到内存设备描述表中
hOldBitmap = (HBITMAP)SelectObject(hMemDC,hBitmap);
// 把屏幕设备描述表拷贝到内存设备描述表中
StretchBlt(hMemDC,SRCcopY);
//BitBlt(hMemDC,SRCcopY);
//得到屏幕位图的句柄
hBitmap = (HBITMAP)SelectObject(hMemDC,hOldBitmap);
//清除
DeleteDC(hMemDC);
DeleteObject(hOldBitmap);
// 返回位图句柄
return hBitmap;
}
//把HBITMAP保存成位图
BOOL SaveBmp(HBITMAP hBitmap,CString FileName)
{
if(hBitmap==NULL || FileName.IsEmpty())
{
return false;
}
2：拷贝屏幕DC包成为BMP格式的文件 ;
//当前分辨率下每象素所占字节数
int iBits;
//位图中每象素所占字节数
WORD wBitCount;
//定义调色板大小， 位图中像素字节大小 ，位图文件大小 ， 写入文件字节数
DWORD dwPaletteSize=0,dwBmBitsSize=0,dwDIBSize=0,dwWritten=0;
//位图属性结构
BITMAP Bitmap;
//位图文件头结构
BITMAPFILEHEADER bmfHdr;
//位图信息头结构
BITMAPINFOHEADER bi;
//指向位图信息头结构
LPBITMAPINFOHEADER lpbi;
//定义文件，分配内存句柄，调色板句柄
HANDLE fh,hDib,hPal,hOldPal=NULL;
//计算位图文件每个像素所占字节数
hDC = CreateDC("disPLAY",NULL);
iBits = GetDeviceCaps(hDC,BITSPIXEL) * GetDeviceCaps(hDC,PLAnes);
DeleteDC(hDC);
if (iBits <= 1) wBitCount = 1;
else if (iBits <= 4) wBitCount = 4;
else if (iBits <= 8) wBitCount = 8;
else wBitCount = 24;
Getobject(hBitmap,sizeof(Bitmap),(LPSTR)&Bitmap);
bi.biSize = sizeof(BITMAPINFOHEADER);
bi.biWidth = Bitmap.bmWidth;
bi.biHeight = Bitmap.bmHeight;
bi.biPlanes = 1;
bi.biBitCount = wBitCount;
bi.biCompression = BI_RGB;
bi.biSizeImage = 0;
bi.biXPelsPerMeter = 0;
bi.biYPelsPerMeter = 0;
bi.biClrImportant = 0;
bi.biClrUsed = 0;
dwBmBitsSize = ((Bitmap.bmWidth * wBitCount + 31) / 32) * 4 * Bitmap.bmHeight;
//为位图内容分配内存
hDib = GlobalAlloc(GHND,dwBmBitsSize + dwPaletteSize + sizeof(BITMAPINFOHEADER));
lpbi = (LPBITMAPINFOHEADER)GlobalLock(hDib);
*lpbi = bi;
// 处理调色板
hPal = GetStockObject(DEFAULT_PALETTE);
if (hPal)
{
hDC = ::GetDC(NULL);
hOldPal = ::SelectPalette(hDC,(HPALETTE)hPal,FALSE);
RealizePalette(hDC);
}
// 获取该调色板下新的像素值
GetDIBits(hDC,hBitmap,(UINT) Bitmap.bmHeight,(LPSTR)lpbi + sizeof(BITMAPINFOHEADER)
+dwPaletteSize,(BITMAPINFO *)lpbi,DIB_RGB_COLORS);
//恢复调色板
if (hOldPal)
{
::SelectPalette(hDC,(HPALETTE)hOldPal,TRUE);
RealizePalette(hDC);
::ReleaseDC(NULL,hDC);
}
//创建位图文件
fh = CreateFile(FileName,GENERIC_WRITE,CREATE_ALWAYS,
FILE_ATTRIBUTE_norMAL | FILE_FLAG_SEQUENTIAL_SCAN,NULL);
if (fh == INVALID_HANDLE_VALUE) return FALSE;
// 设置位图文件头
bmfHdr.bfType = 0x4D42; // "BM"
dwDIBSize = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) + dwPaletteSize + dwBmBitsSize;
bmfHdr.bfSize = dwDIBSize;
bmfHdr.bfReserved1 = 0;
bmfHdr.bfReserved2 = 0;
bmfHdr.bfOffBits = (DWORD)sizeof(BITMAPFILEHEADER) + (DWORD)sizeof(BITMAPINFOHEADER) + dwPaletteSize;
// 写入位图文件头
WriteFile(fh,(LPSTR)&bmfHdr,sizeof(BITMAPFILEHEADER),&dwWritten,NULL);
// 写入位图文件其余内容
WriteFile(fh,(LPSTR)lpbi,dwDIBSize,NULL);
//清除
GlobalUnlock(hDib);
GlobalFree(hDib);
CloseHandle(fh);
return TRUE;
}
int Engine_2D::SaveBitmapToFile(HBITMAP hBitmap, LPCWSTR lpFileName) //hBitmap 为刚才的屏幕位图句柄
{
//lpFileName 为位图文件名
HDC hDC;
//设备描述表
int iBits;
//当前显示分辨率下每个像素所占字节数
WORD wBitCount;
//位图中每个像素所占字节数
//定义调色板大小， 位图中像素字节大小 ， 位图文件大小 ， 写入文件字节数
DWORD dwPaletteSize=0,dwBmBitsSize, dwWritten;
BITMAP Bitmap;
//位图属性结构
BITMAPFILEHEADER bmfHdr;
//位图文件头结构
BITMAPINFOHEADER bi;
//位图信息头结构
LPBITMAPINFOHEADER lpbi;
//指向位图信息头结构
HANDLE fh, hDib, hPal;
HPALETTE hOldPal=NULL;
//定义文件，分配内存句柄，调色板句柄
//计算位图文件每个像素所占字节数
hDC = CreateDC(L"disPLAY",NULL);
iBits = GetDeviceCaps(hDC, BITSPIXEL) * GetDeviceCaps(hDC, PLAnes);
DeleteDC(hDC);
if (iBits <= 1)
wBitCount = 1;
else if (iBits <= 4)
wBitCount = 4;
else if (iBits <= 8)
wBitCount = 8;
else if (iBits <= 16)
wBitCount = 16;
else if (iBits <= 24)
wBitCount = 24;
else
wBitCount = 32;
//计算调色板大小
if(wBitCount <= 8)
dwPaletteSize=(1<<wBitCount)*sizeof(RGBQUAD);
//设置位图信息头结构
Getobject(hBitmap, sizeof(BITMAP), (LPSTR)&Bitmap);
bi.biSize = sizeof(BITMAPINFOHEADER);
bi.biWidth = Bitmap.bmWidth;
bi.biHeight = Bitmap.bmHeight;
bi.biPlanes = 1;
bi.biBitCount = wBitCount;
bi.biCompression = BI_RGB;
bi.biSizeImage = 0;
bi.biXPelsPerMeter = 0;
bi.biYPelsPerMeter = 0;
bi.biClrUsed = 0;
bi.biClrImportant = 0;
dwBmBitsSize = ((Bitmap.bmWidth*wBitCount+31)/32)*4*Bitmap.bmHeight;
//为位图内容分配内存
hDib = GlobalAlloc(GHND,dwBmBitsSize+dwPaletteSize+sizeof(BITMAPINFOHEADER));
lpbi = (LPBITMAPINFOHEADER)GlobalLock(hDib);
*lpbi = bi;
// 处理调色板
hPal = GetStockObject(DEFAULT_PALETTE);
if (hPal)
{
hDC = GetDC(NULL);
hOldPal=SelectPalette(hDC,FALSE);
RealizePalette(hDC);
}
// 获取该调色板下新的像素值
GetDIBits(hDC,(UINT)Bitmap.bmHeight,(LPSTR)lpbi+sizeof(BITMAPINFOHEADER)+dwPaletteSize, (BITMAPINFO *)lpbi,DIB_RGB_COLORS);
//恢复调色板
if (hOldPal)
{
SelectPalette(hDC, hOldPal, TRUE);
RealizePalette(hDC);
ReleaseDC(NULL, hDC);
}
//创建位图文件
fh=CreateFile(lpFileName, GENERIC_WRITE, NULL, CREATE_ALWAYS,FILE_ATTRIBUTE_norMAL | FILE_FLAG_SEQUENTIAL_SCAN, NULL);
if (fh==INVALID_HANDLE_VALUE)
return FALSE;
// 设置位图文件头
bmfHdr.bfType = 0x4D42; // "BM"
dwDIBSize=sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER)+dwPaletteSize+dwBmBitsSize;
bmfHdr.bfSize = dwDIBSize;
bmfHdr.bfReserved1 = 0;
bmfHdr.bfReserved2 = 0;
bmfHdr.bfOffBits = (DWORD)sizeof(BITMAPFILEHEADER)+(DWORD)sizeof(BITMAPINFOHEADER)+dwPaletteSize;
// 写入位图文件头
WriteFile(fh, (LPSTR)&bmfHdr, sizeof(BITMAPFILEHEADER), &dwWritten, NULL);
// 写入位图文件其余内容
WriteFile(fh, (LPSTR)lpbi, dwDIBSize, &dwWritten, NULL);
//清除
GlobalUnlock(hDib);
GlobalFree(hDib);
CloseHandle(fh);
return TRUE;
}
3创建WINCE下16位格式位图实现快速BitBlt
在WINCE下，如果创建的位图与屏幕设备格式不一样，将会导致BitBlt函数极为缓慢，因此需要创建一幅16位色565格式位图，用此方法创建出的位图可以提供1ms的快速BitBlt绘制。当然，如果设备不是565颜色格式的，更改代码中的颜色掩码位bmiColors就可以了。
- /////////////////////////////////////////////////////////////////////////
- /// @brief 创建一幅缓存图像。
- /// @param[out] pHBitmap 生成的位图句柄。
- /// @param[out] pData 生成的位图中的数据位置。
- /// @param[in] hDC 目标DC句柄。
- /// @param[in] width 位图宽度。
- /// @param[in] height 位图高度。
- /// @param[in] bitCount 每个像素占多少个bit。
- /// @attention 创建的位图是无压缩格式的。
- /// @author Loongee
- /// @date 2010/01/15
- //////////////////////////////////////////////////////////////////////////
- void CreateBufferBitmap(HBITMAP* pHBitmap,void** pData,
- HDC hDC,LONG width,LONG height,WORD bitCount)
- {
- BITMAPINFO& bmpInfo = *(BITMAPINFO*)new BYTE[sizeof(bmpInfo) + sizeof(RGBQUAD) * 3];
- bmpInfo.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
- bmpInfo.bmiHeader.biWidth = width;
- bmpInfo.bmiHeader.biHeight = height;
- bmpInfo.bmiHeader.biPlanes = 1;
- bmpInfo.bmiHeader.biBitCount = bitCount;
- if (bitCount == 16)
- {
- bmpInfo.bmiHeader.biCompression = BI_BITFIELDS;
- *(DWORD *)(&bmpInfo.bmiColors[0]) = 0xF800;
- *(DWORD *)(&bmpInfo.bmiColors[1]) = 0x07E0;
- *(DWORD *)(&bmpInfo.bmiColors[2]) = 0x001F;
- }
- else
- {
- bmpInfo.bmiHeader.biCompression = BI_RGB;
- bmpInfo.bmiHeader.biSizeImage = 0;
- bmpInfo.bmiHeader.biXPelsPerMeter = 1000;
- bmpInfo.bmiHeader.biYPelsPerMeter = 1000;
- bmpInfo.bmiHeader.biClrUsed = 0;
- bmpInfo.bmiHeader.biClrImportant = 0;
- *pHBitmap = CreateDIBSection(hDC,&bmpInfo,DIB_RGB_COLORS
- ,pData,0);
- delete[] (BYTE*)&bmpInfo;
- }
待续。。。。。。。
