internal List<Slice> GetCloseSlices()
{
int index = IndexInContainer;
var closeSlices = new List<Slice> {this};
var count = ContainingDataTree.Slices.Count;
int limit = Math.Min(Math.Max(index, count - index), 40);
for (int i = 1; i <= limit; i++)
{
if (index - i >= 0)
closeSlices.Add(ContainingDataTree.FieldOrDummyAt(index - i));
if (index + i < count)
closeSlices.Add(ContainingDataTree.FieldOrDummyAt(index + i));
}
return closeSlices;
}