local rowPanelsWithX =
      std.map(
        function(row)
          row + { panels: std.mapWithIndex(CalculateXforPanel, row.panels) },
        rowPanels
      );

    local uncollapsed = panelUtil.resolveCollapsedFlagOnRows(panelsBeforeRowsWithX + rowPanelsWithX);

    local normalized = panelUtil.normalizeY(uncollapsed);

    std.map(function(p) p + { gridPos+: { y+: startY } }, normalized),