--- a/pkg/imports/isr.go	Mon Oct 14 13:18:15 2019 +0200
+++ b/pkg/imports/isr.go	Mon Oct 14 14:58:04 2019 +0200
@@ -171,11 +171,11 @@
 
 	// For all sounding results in bottleneck.
 	for _, sr := range bn.srs {
-		tree, err := octree.FetchOctreeDirectly(ctx, tx, sr)
+		tree, err := octree.FetchMeshDirectly(ctx, tx, sr)
 		if err != nil {
 			return err
 		}
-		hs := octree.ExtrapolateClassBreaks(heights, tree.Min.Z, tree.Max.Z)
+		hs := octree.ExtrapolateClassBreaks(heights, tree.Min().Z, tree.Max().Z)
 		hs = common.DedupFloat64s(hs)
 
 		// Delete the old iso areas.
@@ -184,7 +184,7 @@
 		}
 
 		// Calculate and store the iso areas.
-		areas := octree.TraceAreas(hs, isoCellSize, tree.Min, tree.Max, tree.Value)
+		areas := octree.TraceAreas(hs, isoCellSize, tree.Min(), tree.Max(), tree.Value)
 		for i, a := range areas {
 			if len(a) == 0 {
 				continue