Smooth triangle with QGuiApplication::setAttribute(Qt::AA_UseSoftwareOpenGL, true)

unclebenedict

Im use QSGNode and QQuickItem for paint my item on qml scene. If user have weak graphics card, then item can not paint. In low graphics card im use QGuiApplication::setAttribute(Qt::AA_UseSoftwareOpenGL, true) for softfare opengl, all item paint, but not smooth. Example http://joxi.ru/wRmzQXSW65N6rO?d=1

Im try

QQuickView view;
QSurfaceFormat format = view.format();
format.setSamples(8);
view.setFormat(format);

but this not work on software opengl. How i can smoot triangle on software opengl ?