M>void PaintOnPaint(HWND hWnd)
M>{
M>    PAINTSTRUCT ps;
M>    HDC hDC = BeginPaint(hWnd, &ps);
M>    CBitmap *pBitmap = (CBitmap*)GetProp(hWnd, _T("BMP"));
M>    if (!pBitmap->IsEmpty())
M>    {
M>        RECT rc;
M>        GetClientRect(hWnd, &rc);
M>        HBITMAP hBmp = CreateCompatibleBitmap(hDC, rc.right - rc.left, rc.bottom - rc.top);
M>        HDC hMemDC = CreateCompatibleDC(hDC);
M>        HBITMAP hOldBmp = (HBITMAP)SelectObject(hMemDC, hBmp);
M>        HBRUSH hBrush = (HBRUSH)GetClassLong(hWnd, GCL_HBRBACKGROUND);
M>        if (hBrush != 0)
M>        {
M>            FillRect(hMemDC, &rc, hBrush);
M>        }
M>        int X = (rc.right - rc.left - pBitmap->GetWidth()) / 2;
M>        if (X < 0)
M>        {
M>            X = -GetScrollPos(hWnd, SB_HORZ);
M>        }
M>        int Y = (rc.bottom - rc.top - pBitmap->GetHeight()) / 2;
M>        if (Y < 0)
M>        {
M>            Y = -GetScrollPos(hWnd, SB_VERT);
M>        }
M>        if (GetDeviceCaps(hMemDC, RASTERCAPS) & RC_BITBLT)
M>        {
M>            pBitmap->Draw(hMemDC, X + g_dx, Y + g_dy);
M>        }
M>        if (GetDeviceCaps(hDC, RASTERCAPS) & RC_BITBLT)
M>        {
M>            BitBlt(hDC, 0, 0, rc.right - rc.left, rc.bottom - rc.top, hMemDC, 0, 0, SRCCOPY);
M>        }
M>        SelectObject(hMemDC, hOldBmp);
M>        DeleteDC(hMemDC);
M>        DeleteObject(hBmp);
M>    }
M>    EndPaint(hWnd, &ps);
M>}

M>