// gc->set_function(Gdk::INVERT);
// gc->set_line_attributes(1,Gdk::LINE_SOLID,Gdk::CAP_BUTT,Gdk::JOIN_MITER);
// drawable->draw_lines(gc, Glib::ArrayHandle<Gdk::Point>(points));
// gc->set_function(Gdk::INVERT);
// gc->set_line_attributes(1,Gdk::LINE_SOLID,Gdk::CAP_BUTT,Gdk::JOIN_MITER);
// drawable->draw_lines(gc, Glib::ArrayHandle<Gdk::Point>(points));