public Rectangular vsplit(Rectangular other)
    {
        if (this.intersects(other))
        {
            Rectangular a = new Rectangular(this);
            Rectangular b = new Rectangular(this);
            if (a.y2 > other.y1 - 1) a.y2 = other.y1 - 1;
            if (b.y1 < other.y2 + 1) b.y1 = other.y2 + 1;
            if (a.isEmpty())
            {
                y1 = b.y1;
                return null;
            }
            else
            {
                y2 = a.y2;
                if (b.isEmpty())
                    return null;
                else
                    return b;
            }
        }
        else
            return null;
    }