[WinApi]Screenshot konkretnego okna

HDC hdcScreen = GetDC( hwnd );
RECT rect;
HBITMAP hbmC;

GetClientRect( hwnd, & rect );

if(( hbmC = CreateCompatibleBitmap( hdcScreen, rect.right, rect.bottom ) ) != NULL )
{
    HDC hdcC;
    if(( hdcC = CreateCompatibleDC( hdcScreen ) ) != NULL )
    {
        HBITMAP hbmOld =( HBITMAP ) SelectObject( hdcC, hbmC );
       
        BitBlt( hdcC, 0, 0, rect.right, rect.bottom, hdcScreen, 0, 0, SRCCOPY );
       
        SelectObject( hdcC, hbmOld );
        DeleteDC( hdcC );
    }
}

RECT re; //pozycja okna
GetWindowRect( hwnd, & re );
QPixmap tmp = QPixmap::fromWinHBITMAP( hbmC );
lupaFrame::getInstance().painter->drawPixmap( re.left, re.top, tmp.width(), tmp.height(), tmp );
ReleaseDC( hwnd, hdcScreen );