/// Рисование карты и траектории Сахарой
void QTrackWidget::paintEvent(QPaintEvent* events)
{
    QPainter painter(this);

    // anything
        painter.setPen(QPen(Qt::black, 1, Qt::SolidLine));    ///< установка цвета линий
        QPoint p1(calc_distance -> beginPoint()), p2(calc_distance -> endPoint());
            painter.drawLine(p1, p2);

    painter.setPen(QPen(Qt::blue, 1, Qt::SolidLine));    ///< установка цвета траектории

    QWidget::paintEvent(events);
}