diff --git a/common/graph_rtree.go b/common/graph_rtree.go
index d7d9684..a090214 100644
--- a/common/graph_rtree.go
+++ b/common/graph_rtree.go
@@ -4,9 +4,10 @@ import (
 	"github.com/dhconnelly/rtreego"
 
 	"math"
+	"reflect"
 )
 
-func RtreegoRect(r Rectangle) *rtreego.Rect {
+func RtreegoRect(r Rectangle) rtreego.Rect {
 	dx := math.Max(0.00000001, r.Max.X - r.Min.X)
 	dy := math.Max(0.00000001, r.Max.Y - r.Min.Y)
 	rect, err := rtreego.NewRect(rtreego.Point{r.Min.X, r.Min.Y}, []float64{dx, dy})
@@ -18,11 +19,12 @@ func RtreegoRect(r Rectangle) *rtreego.Rect {
 
 type edgeSpatial struct {
 	edge *Edge
-	rect *rtreego.Rect
+	rect rtreego.Rect
 }
 
-func (e *edgeSpatial) Bounds() *rtreego.Rect {
-	if e.rect == nil {
+func (e *edgeSpatial) Bounds() rtreego.Rect {
+	isEmpty := reflect.DeepEqual(rtreego.Rect{}, e.rect)
+	if isEmpty {
 		r := e.edge.Src.Point.Rectangle()
 		r = r.Extend(e.edge.Dst.Point)
 		e.rect = RtreegoRect(r)