private List<Vector3f> cloneVectorList(SafeArrayList<Vector3f> locations) {

        final List<Vector3f> cloned = new ArrayList<>(locations.size());

        for (final Vector3f location : locations.getArray()) {
            cloned.add(location.clone());
        }

        return cloned;
    }
Back on the ogl thread: update the terrain patch geometries
jme3-terrain/src/main/java/com/jme3/terrain/geomipmap/TerrainLodControl.java