--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/pkg/octree/node.go	Fri Mar 01 15:33:27 2019 +0100
@@ -0,0 +1,49 @@
+// Copyright (C) 2018 Michael Fogleman
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the "Software"),
+// to deal in the Software without restriction, including without limitation
+// the rights to use, copy, modify, merge, publish, distribute, sublicense,
+// and/or sell copies of the Software, and to permit persons to whom the
+// Software is furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+package octree
+
+type node struct {
+	i    int
+	t    int
+	prev *node
+	next *node
+}
+
+func newNode(nodes []node, i int, prev *node) *node {
+	n := &nodes[i]
+	n.i = i
+	if prev == nil {
+		n.prev = n
+		n.next = n
+	} else {
+		n.next = prev.next
+		n.prev = prev
+		prev.next.prev = n
+		prev.next = n
+	}
+	return n
+}
+
+func (n *node) remove() *node {
+	n.prev.next = n.next
+	n.next.prev = n.prev
+	n.i = -1
+	return n.prev
+}