public void Test_S2CellId_ParentChildRelationships()
{
S2CellId id = S2CellId.FromFacePosLevel(3, 0x12345678, S2.kMaxCellLevel - 4);
Assert.True(id.IsValid());
Assert.Equal(3UL, id.Face());
Assert.Equal(0x12345700UL, id.Pos());
Assert.Equal(S2.kMaxCellLevel - 4, id.Level());
Assert.False(id.IsLeaf());
Assert.Equal(0x12345610UL, id.ChildBegin(id.Level() + 2).Pos());
Assert.Equal(0x12345640UL, id.ChildBegin().Pos());
Assert.Equal(0x12345400UL, id.Parent().Pos());
Assert.Equal(0x12345000UL, id.Parent(id.Level() - 2).Pos());
// Check ordering of children relative to parents.
Assert.True(id.ChildBegin() < id);
Assert.True(id.ChildEnd() > id);
Assert.Equal(id.ChildEnd(), id.ChildBegin().Next().Next().Next().Next());
Assert.Equal(id.RangeMin(), id.ChildBegin(S2.kMaxCellLevel));
Assert.Equal(id.RangeMax().Next(), id.ChildEnd(S2.kMaxCellLevel));
// Check that cells are represented by the position of their center
// along the Hilbert curve.
Assert.Equal(2 * id.Id, id.RangeMin().Id + id.RangeMax().Id);
}
public void Test_S2CellId_Advance()
{
S2CellId id = S2CellId.FromFacePosLevel(3, 0x12345678,
S2.kMaxCellLevel - 4);
// Check basic properties of advance().
Assert.Equal(S2CellId.End(0), S2CellId.Begin(0).Advance(7));
Assert.Equal(S2CellId.End(0), S2CellId.Begin(0).Advance(12));
Assert.Equal(S2CellId.Begin(0), S2CellId.End(0).Advance(-7));
Assert.Equal(S2CellId.Begin(0), S2CellId.End(0).Advance(-12000000));
int num_level_5_cells = 6 << (2 * 5);
Assert.Equal(S2CellId.End(5).Advance(500 - num_level_5_cells),
S2CellId.Begin(5).Advance(500));
Assert.Equal(id.Next().ChildBegin(S2.kMaxCellLevel),
id.ChildBegin(S2.kMaxCellLevel).Advance(256));
Assert.Equal(S2CellId.FromFacePosLevel(5, 0, S2.kMaxCellLevel),
S2CellId.FromFacePosLevel(1, 0, S2.kMaxCellLevel)
.Advance((long)(4UL << (2 * S2.kMaxCellLevel))));
// Check basic properties of advance_wrap().
Assert.Equal(S2CellId.FromFace(1), S2CellId.Begin(0).AdvanceWrap(7));
Assert.Equal(S2CellId.Begin(0), S2CellId.Begin(0).AdvanceWrap(12));
Assert.Equal(S2CellId.FromFace(4), S2CellId.FromFace(5).AdvanceWrap(-7));
Assert.Equal(S2CellId.Begin(0), S2CellId.Begin(0).AdvanceWrap(-12000000));
Assert.Equal(S2CellId.Begin(5).AdvanceWrap(6644),
S2CellId.Begin(5).AdvanceWrap(-11788));
Assert.Equal(id.Next().ChildBegin(S2.kMaxCellLevel),
id.ChildBegin(S2.kMaxCellLevel).AdvanceWrap(256));
Assert.Equal(S2CellId.FromFacePosLevel(1, 0, S2.kMaxCellLevel),
S2CellId.FromFacePosLevel(5, 0, S2.kMaxCellLevel)
.AdvanceWrap((long)(2UL << (2 * S2.kMaxCellLevel))));
}
// Returns true if "covering" contains all children of "id" at level
// (id.Level + options_.level_mod()).
private bool ContainsAllChildren(List <S2CellId> covering, S2CellId id)
{
var it = covering.GetLowerBound(id.RangeMin());
int level = id.Level() + Options_.LevelMod;
var limit = id.ChildEnd(level);
for (var child = id.ChildBegin(level); child != limit; child = child.Next())
{
if (it == covering.Count || covering[it] != child)
{
return(false);
}
it++;
}
return(true);
}