Change StaticRTree serialization constructor to static function

Since the constructor does not satisfy the requirements for a
constructor (the RTree is not properly initialized) make it a
static function instead.

Contractor/Prepare.cpp

@@ -170,7 +170,10 @@ int Prepare::Process(int argc, char *argv[])
 
     TIMER_STOP(expansion);
 
-    BuildRTree(node_based_edge_list);
+    StaticRTree<EdgeBasedNode>::Build(node_based_edge_list,
+                                      rtree_nodes_path.c_str(),
+                                      rtree_leafs_path.c_str(),
+                                      internal_to_external_node_map);
 
     IteratorbasedCRC32<std::vector<EdgeBasedNode>> crc32;
     const unsigned node_based_edge_list_CRC32 =
@@ -544,16 +547,3 @@ void Prepare::WriteNodeMapping()
     internal_to_external_node_map.shrink_to_fit();
 }
 
-/**
-    \brief Building rtree-based nearest-neighbor data structure
-
-    Saves info to files: '.ramIndex' and '.fileIndex'.
- */
-void Prepare::BuildRTree(std::vector<EdgeBasedNode> &node_based_edge_list)
-{
-    SimpleLogger().Write() << "building r-tree ...";
-    StaticRTree<EdgeBasedNode>(node_based_edge_list,
-                               rtree_nodes_path.c_str(),
-                               rtree_leafs_path.c_str(),
-                               internal_to_external_node_map);
-}

Contractor/Prepare.h

@@ -40,7 +40,6 @@ class Prepare
                                 DeallocatingVector<EdgeBasedEdge> &edgeBasedEdgeList,
                                 EdgeBasedGraphFactory::SpeedProfileProperties &speed_profile);
     void WriteNodeMapping();
-    void BuildRTree(std::vector<EdgeBasedNode> &node_based_edge_list);
 
   private:
     std::vector<NodeInfo> internal_to_external_node_map;