请问如何用cbitmap类在内存里，画一个图形，然后将该图形存成bmp文件

Question

请问如何用cbitmap类在内存里，画一个图形，然后将该图形存成bmp文件

Answer 1

http://www.codeproject.com/bitmap/bitmapdc.asp
CBitmapDC - An automatic memory DC wrapper

Answer 2

void savebmp(CBitmap& bmp)
{
CPictureHolder picture;
picture.CreateFromBitmap((HBITMAP)bmp, NULL, TRUE);
LPPICTUREDISP pPictureDisp=picture.GetPictureDispatch();
pPictureDisp->Release(); // must be released
IStorage* pStg = 0;        hr = ::StgCreateDocfile(L"c:\\picttest",
              STGM_SHARE_EXCLUSIVE |
              STGM_CREATE |
              STGM_READWRITE,
              0, &pStg);
        if(SUCCEEDED(hr))
        {
            IStream* pStream = 0;            hr = pStg->CreateStream(L"PICTURE",
                  STGM_SHARE_EXCLUSIVE |
                  STGM_CREATE |
                  STGM_READWRITE,
                  0, 0, &pStream);
            if(SUCCEEDED(hr))
            {
                hr = pPictureDisp->SaveAsFile(pStream,
                      TRUE, // save mem copy
                      NULL);
                pStream->Release();
            }
            pStg->Release();
        }
        pPictureDisp->Release();
}

Answer 3

画图形的代码
CRect rt;
GetClientRect(rt);
CBitmap bitmap;
CBitmap* pOldbitmap;
CDC MemDC;
MemDC.CreateCompatibleDC(pDC);
bitmap.LoadBitmap(IDB_WORKSPACE);
pOldbitmap = MemDC.SelectObject(&bitmap);
pDC->BitBlt(50,50,rt.Width()-10,rt.Height()-10,&MemDC,0,0,SRCCOPY);
MemDC.SelectObject(pOldbitmap);
MemDC.DeleteDC();

Answer 4

画图形的代码
CRect rt;
GetClientRect(rt);
CBitmap bitmap;
CBitmap* pOldbitmap;
CDC MemDC;
MemDC.CreateCompatibleDC(pDC);
bitmap.LoadBitmap(IDB_WORKSPACE);
pOldbitmap = MemDC.SelectObject(&bitmap);
pDC->BitBlt(50,50,rt.Width()-10,rt.Height()-10,&MemDC,0,0,SRCCOPY);
MemDC.SelectObject(pOldbitmap);
MemDC.DeleteDC();

Answer 5

存图形的代码
CBitmap bitmap;
HANDLE h=::LoadImage(0,"f:\\aaa.bmp",IMAGE_BITMAP,0,0,LR_LOADFROMFILE);
bitmap.Attach(h);——————————————————————————
CFile file("F:\\aaa1.bmp",CFile::modeCreate|CFile::modeWrite);
CArchive ar(&file,CArchive::store); BITMAP size;
bitmap.GetBitmap(&size);
int iHeight=size.bmHeight;
int iWidth=size.bmWidth;
int WIDTHBYTES;
unsigned char * pBitBuf=NULL; WIDTHBYTES=(iWidth*3+3)/4*4;
pBitBuf=(unsigned char *)malloc(WIDTHBYTES*iHeight); BITMAPFILEHEADER BitFileHead;
BITMAPINFOHEADER BitInfoHead;
BitInfoHead.biHeight=iHeight;
BitInfoHead.biWidth=iWidth;
BitInfoHead.biSizeImage=WIDTHBYTES*iHeight;
BitInfoHead.biSize          = sizeof(BITMAPINFOHEADER);
BitInfoHead.biPlanes        = 1;
BitInfoHead.biBitCount      = 24;
BitInfoHead.biCompression   = BI_RGB;
BitInfoHead.biXPelsPerMeter = 2952; // 75 DPI 
BitInfoHead.biYPelsPerMeter = 2952; // 75 DPI 
BitInfoHead.biClrUsed       = 0;
BitInfoHead.biClrImportant  = 0;

BitFileHead.bfType      = 'MB'; // Non-portable... sigh 
BitFileHead.bfSize      = BitInfoHead.biSizeImage+sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER);
BitFileHead.bfReserved1 = 0;
BitFileHead.bfReserved2 = 0;
BitFileHead.bfOffBits   =sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER); BITMAPINFO mapinfo;
mapinfo.bmiHeader=BitInfoHead;
// mapinfo.bmiColors HDC hdc = CreateIC (TEXT("DISPLAY"), NULL, NULL, NULL) ;
::GetDIBits (hdc, (HBITMAP)h,0, iHeight, pBitBuf, &mapinfo, DIB_RGB_COLORS) ;
file.Write(&BitFileHead,sizeof(BITMAPFILEHEADER));
file.Write(&BitInfoHead,sizeof(BITMAPINFOHEADER));
file.Write(pBitBuf,WIDTHBYTES*iHeight); free(pBitBuf);

ar.Close();
file.Close();
bitmap.DeleteObject();

Answer 6

这里有个例子程序，是从界面DC保存图像到bmp文件，把界面dc换成内存dc就可以了
http://www.yangning.com/cgi-bin/topic.cgi?forum=1&topic=82&show=0

Answer 7

保存一个文件要这么多啊！
GDI 完全不熟：（