public Designator_StripMine()
 {
     UseDesignatorDef(AllowToolDefOf.StripMineDesignator);
     highlighter                = new MapCellHighlighter(EnumerateHighlightCells);
     Dragger.SelectionStart    += DraggerOnSelectionStart;
     Dragger.SelectionChanged  += DraggerOnSelectionChanged;
     Dragger.SelectionComplete += DraggerOnSelectionComplete;
     updateCallback             = OnUpdate;
 }
        protected Designator_SelectableThings()
        {
            var highlighter = new MapCellHighlighter(SelectHighlightedCells);
            Action <CellRect> clearHighlightedCells = r => highlighter.ClearCachedCells();

            Dragger.SelectionStart    += clearHighlightedCells;
            Dragger.SelectionChanged  += clearHighlightedCells;
            Dragger.SelectionComplete += clearHighlightedCells;
            Dragger.SelectionUpdate   += r => highlighter.DrawCellHighlights();
        }