// a window for gtk_paint_xxx function, then it won't
// work for wxMemoryDC. So that is why we assume wxDC
// is wxWindowDC (wxClientDC, wxMemoryDC and wxPaintDC
// are derived from it) and use its m_window.
// a window for gtk_paint_xxx function, then it won't
// work for wxMemoryDC. So that is why we assume wxDC
// is wxWindowDC (wxClientDC, wxMemoryDC and wxPaintDC
// are derived from it) and use its m_window.