New cpp folder structure

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

tools/topography_generator/isolines_utils.hpp

@@ -0,0 +1,35 @@
+#pragma once
+#include "generator/srtm_parser.hpp"
+
+#include "storage/storage_defines.hpp"
+
+#include "indexer/feature_altitude.hpp"
+
+#include "base/file_name_utils.hpp"
+
+#include <string>
+
+namespace topography_generator
+{
+using Altitude = geometry::Altitude;
+Altitude constexpr kInvalidAltitude = geometry::kInvalidAltitude;
+
+constexpr char const * const kIsolinesExt = ".isolines";
+
+inline std::string GetIsolinesTileBase(int bottomLat, int leftLon)
+{
+  auto const centerPoint = ms::LatLon(bottomLat + 0.5, leftLon + 0.5);
+  return generator::SrtmTile::GetBase(centerPoint);
+}
+
+inline std::string GetIsolinesFilePath(int bottomLat, int leftLon, std::string const & dir)
+{
+  auto const fileName = GetIsolinesTileBase(bottomLat, leftLon);
+  return base::JoinPath(dir, fileName + kIsolinesExt);
+}
+
+inline std::string GetIsolinesFilePath(storage::CountryId const & countryId, std::string const & dir)
+{
+  return base::JoinPath(dir, countryId + kIsolinesExt);
+}
+}  // namespace topography_generator