void MyTableHeader::headerSectionClicked(int section_index, int click_pos)
{
    int section_size = sectionSize(0); // All sections in a header are equally sized
    int section_center = (section_size * (section_index+ 1)) - (section_size / 2); // Center of the clicked section

    if (section_index>= 0)// if mouse is over an item
    {
        if (orientation() == Qt::Horizontal)
        {
            QPoint x_pos = QPoint(click_pos, 0);
            int mapped_offset = viewport()->mapFrom(this, x_pos).x();

            if (mapped_offset != -1)
            {
                // If the click was to the right of the center, iterate on the index
                if (mapped_offset >= section_center)
                {
                    in_index++;
                }
            }
        }
        else
        {
            // Same thing for the Y-dimension
        }
    }

    // Neat stuff after this
}

// If the click was to the right of the center, iterate on the index
if (mapped_offset >= section_center)
{
    in_index++;
}