StretchBlt 提高图片显示质量的方法

通过SetStretchMode(STRETCH_HALFTONE)实现，同时注意重新设置画刷起点

LRESULT CMainDlg::OnPaint(UINT uMsg, WPARAM wParam, LPARAM /*lParam*/, BOOL& bHandled) {

    CPaintDC dc(m_hWnd);

    CDC memDC;

    memDC.CreateCompatibleDC(dc);

    memDC.SelectBitmap((HBITMAP)m_cap_pic);

    dc.SetStretchBltMode(STRETCH_HALFTONE);

    ::SetBrushOrgEx(dc, , , NULL);

    dc.StretchBlt(m_rc_capture.left, m_rc_capture.top, m_rc_capture.Width(),

        m_rc_capture.Height(), memDC, , , m_cap_pic.GetWidth(),

        m_cap_pic.GetHeight(), SRCCOPY);

    bHandled = FALSE;

    return ;

}