bool GridAttributes::operator==( const GridAttributes& r ) const
{
    return  isGridVisible() == r.isGridVisible() &&
            gridGranularitySequence() == r.gridGranularitySequence() &&
            adjustLowerBoundToGrid() == r.adjustLowerBoundToGrid() &&
            adjustUpperBoundToGrid() == r.adjustUpperBoundToGrid() &&
            gridPen() == r.gridPen() &&
            isSubGridVisible() == r.isSubGridVisible() &&
            subGridPen() == r.subGridPen() &&
            zeroLinePen() == r.zeroLinePen();
}