void wxMemoryDC::SelectObject(const wxBitmap& bitmap)
{
    if ( bitmap.Ok() )
    {
        m_selected = bitmap;
        SetMGLDC(m_selected.CreateTmpDC(), TRUE);
    }
}
wxScreenDC::wxScreenDC()
           :wxDC()
{
    SetMGLDC(g_displayDC, FALSE /* no ownership */);

    // VS: we have to hide the mouse, otherwise rendering artifacts may occur
    MS_obscure();
}