New cpp folder structure

Signed-off-by: Alexander Borsuk <me@alex.bio>

libs/routing/regions_sparse_graph.hpp

@@ -0,0 +1,46 @@
+#pragma once
+
+#include "routing/cross_border_graph.hpp"
+#include "routing/fake_ending.hpp"
+#include "routing/latlon_with_altitude.hpp"
+#include "routing/regions_decl.hpp"
+#include "routing/segment.hpp"
+
+#include "routing/base/small_list.hpp"
+
+#include <optional>
+
+namespace routing
+{
+
+// Graph used in IndexGraphStarter for building routes through the most important roads which are
+// extracted from World.mwm. These roads are presented as pairs of points between regions.
+class RegionsSparseGraph
+{
+public:
+  RegionsSparseGraph(CountryFileGetterFn const & countryFileGetter,
+                     std::shared_ptr<NumMwmIds> numMwmIds, DataSource & dataSource);
+
+  // Loads data from mwm section.
+  void LoadRegionsSparseGraph();
+
+  std::optional<FakeEnding> GetFakeEnding(m2::PointD const & point) const;
+
+  using EdgeListT = SmallList<SegmentEdge>;
+  void GetEdgeList(Segment const & segment, bool isOutgoing, EdgeListT & edges,
+                   ms::LatLon const & prevSegFront) const;
+
+  routing::LatLonWithAltitude const & GetJunction(Segment const & segment, bool front) const;
+
+  RouteWeight CalcSegmentWeight(Segment const & segment) const;
+
+private:
+  CrossBorderSegment const & GetDataById(RegionSegmentId const & id) const;
+
+  CrossBorderGraph m_graph;
+
+  CountryFileGetterFn const m_countryFileGetterFn;
+  std::shared_ptr<NumMwmIds> m_numMwmIds = nullptr;
+  DataSource & m_dataSource;
+};
+}  // namespace routing