Merge pull request #82 from Workiva/hilbert_delete

Added delete.

Author: dustinhiatt-wf

rtree/hilbert/cpu.prof

@@ -77,6 +77,11 @@ func (ns *nodes) len() uint64 {
 	return uint64(len(ns.list))
 }
 
+func (ns *nodes) deleteAt(i uint64) {
+	copy(ns.list[i:], ns.list[i+1:])
+	ns.list = ns.list[:len(ns.list)-1]
+}
+
 func newNodes(size uint64) *nodes {
 	return &nodes{
 		list: make(rtree.Rectangles, 0, size),
@@ -106,6 +111,11 @@ func (ks *keys) byPosition(i uint64) hilbert {
 	return ks.list[i]
 }
 
+func (ks *keys) deleteAt(i uint64) {
+	copy(ks.list[i:], ks.list[i+1:])
+	ks.list = ks.list[:len(ks.list)-1]
+}
+
 func (ks *keys) delete(k hilbert) hilbert {
 	i := ks.search(k)
 	if i >= uint64(len(ks.list)) {
@@ -116,9 +126,7 @@ func (ks *keys) delete(k hilbert) hilbert {
 		return -1
 	}
 	old := ks.list[i]
-
-	copy(ks.list[i:], ks.list[i+1:])
-	ks.list = ks.list[:len(ks.list)-1]
+	ks.deleteAt(i)
 	return old
 }
 
@@ -223,6 +231,22 @@ func (n *node) insert(kb *keyBundle) rtree.Rectangle {
 	return nil
 }
 
+func (n *node) delete(kb *keyBundle) rtree.Rectangle {
+	i := n.keys.search(kb.key)
+	if n.keys.byPosition(i) != kb.key { // hilbert value not found
+		return nil
+	}
+
+	if !equal(n.nodes.list[i], kb.left) {
+		return nil
+	}
+
+	old := n.nodes.list[i]
+	n.keys.deleteAt(i)
+	n.nodes.deleteAt(i)
+	return old
+}
+
 func (n *node) LowerLeft() (int32, int32) {
 	return n.mbr.xlow, n.mbr.ylow
 }

rtree/hilbert/node.go

@@ -265,8 +265,8 @@ func (tree *tree) applyNode(n *node, adds, deletes []*keyBundle) {
 			break
 		}
 
-		deleted := n.keys.delete(kb.key)
-		if deleted != -1 {
+		deleted := n.delete(kb)
+		if deleted != nil {
 			atomic.AddUint64(&tree.number, ^uint64(0))
 		}
 	}

rtree/hilbert/tree.go

@@ -75,6 +75,10 @@ func constructRandomMockPoints(num int) rtree.Rectangles {
 	return rects
 }
 
+func constructInfiniteRect() rtree.Rectangle {
+	return newMockRectangle(0, 0, math.MaxInt32, math.MaxInt32)
+}
+
 func TestSimpleInsert(t *testing.T) {
 	r1 := newMockRectangle(0, 0, 10, 10)
 	tree := newTree(3, 3)
@@ -87,6 +91,47 @@ func TestSimpleInsert(t *testing.T) {
 	assert.Equal(t, rtree.Rectangles{r1}, result)
 }
 
+func TestSimpleDelete(t *testing.T) {
+	r1 := newMockRectangle(0, 0, 10, 10)
+	tree := newTree(3, 3)
+	tree.Insert(r1)
+
+	tree.Delete(r1)
+	assert.Equal(t, uint64(0), tree.Len())
+	q := newMockRectangle(5, 5, 15, 15)
+	result := tree.Search(q)
+	assert.Len(t, result, 0)
+}
+
+func TestDeleteIdenticalHilbergNumber(t *testing.T) {
+	r1 := newMockRectangle(0, 0, 20, 20)
+	r2 := newMockRectangle(5, 5, 15, 15)
+	tree := newTree(3, 3)
+	tree.Insert(r1)
+
+	tree.Delete(r2)
+	assert.Equal(t, uint64(1), tree.Len())
+	result := tree.Search(r2)
+	assert.Equal(t, rtree.Rectangles{r1}, result)
+
+	tree.Delete(r1)
+	assert.Equal(t, uint64(0), tree.Len())
+	result = tree.Search(r1)
+	assert.Len(t, result, 0)
+}
+
+func TestDeleteAll(t *testing.T) {
+	points := constructRandomMockPoints(5)
+	tree := newTree(3, 3)
+	tree.Insert(points...)
+	assert.Equal(t, uint64(len(points)), tree.Len())
+
+	tree.Delete(points...)
+	assert.Equal(t, uint64(0), tree.Len())
+	result := tree.Search(constructInfiniteRect())
+	assert.Len(t, result, 0)
+}
+
 func TestTwoInsert(t *testing.T) {
 	r1 := newMockRectangle(0, 0, 10, 10)
 	r2 := newMockRectangle(5, 5, 15, 15)
@@ -350,3 +395,16 @@ func BenchmarkQueryPoints(b *testing.B) {
 		tree.Search(newMockRectangle(i, i, i+10, i+10))
 	}
 }
+
+func BenchmarkQueryBulkPoints(b *testing.B) {
+	numItems := b.N
+	points := constructMockPoints(numItems)
+	tree := newTree(8, 8)
+	tree.Insert(points...)
+
+	b.ResetTimer()
+
+	for i := int32(0); i < int32(b.N); i++ {
+		tree.Search(newMockRectangle(i, i, int32(numItems), int32(numItems)))
+	}
+}