Repo created

generator/srtm_parser.hpp

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+#pragma once
+
+#include "geometry/latlon.hpp"
+
+#include "geometry/point_with_altitude.hpp"
+
+#include "base/macros.hpp"
+
+#include <boost/container_hash/hash.hpp>
+
+#include <cstdint>
+#include <string>
+#include <unordered_map>
+#include <utility>
+#include <vector>
+
+namespace generator
+{
+class SrtmTile
+{
+public:
+  SrtmTile() : m_valid(false) {}
+  SrtmTile(SrtmTile && rhs);
+
+  void Init(std::string const & dir, ms::LatLon const & coord);
+
+  inline bool IsValid() const { return m_valid; }
+  /// @return Height in meters at |coord| or kInvalidAltitude.
+  /// @{
+  /// Nearest serialized height.
+  geometry::Altitude GetHeight(ms::LatLon const & coord) const;
+  /// Triangle interpolation.
+  double GetTriangleHeight(ms::LatLon const & coord) const;
+  /// Bilinear interpolation.
+  double GetBilinearHeight(ms::LatLon const & coord) const;
+
+  geometry::Altitude GetAltitude(ms::LatLon const & coord) const
+  {
+    return static_cast<geometry::Altitude>(std::round(GetBilinearHeight(coord)));
+  }
+  /// @}
+
+  using LatLonKey = std::pair<int32_t, int32_t>;
+  static LatLonKey GetKey(ms::LatLon const & coord);
+
+  static std::string GetBase(ms::LatLon const & coord);
+  static std::string GetPath(std::string const & dir, std::string const & base);
+
+  /// Used in unit tests only to prepare mock tile.
+  geometry::Altitude * DataForTests(size_t & sz);
+
+private:
+  static ms::LatLon GetCoordInSeconds(ms::LatLon const & coord);
+  geometry::Altitude GetHeightRC(size_t row, size_t col) const;
+
+  inline geometry::Altitude const * Data() const { return reinterpret_cast<geometry::Altitude const *>(m_data.data()); }
+
+  inline size_t Size() const { return m_data.size() / sizeof(geometry::Altitude); }
+  void Invalidate();
+
+  std::vector<uint8_t> m_data;
+  bool m_valid;
+
+  DISALLOW_COPY(SrtmTile);
+};
+
+class SrtmTileManager
+{
+public:
+  explicit SrtmTileManager(std::string const & dir) : m_dir(dir) {}
+
+  SrtmTile const & GetTile(ms::LatLon const & coord);
+
+  geometry::Altitude GetAltitude(ms::LatLon const & coord) { return GetTile(coord).GetAltitude(coord); }
+
+  size_t GeTilesNumber() const { return m_tiles.size(); }
+
+  void Purge();
+
+private:
+  std::string m_dir;
+
+  struct Hash
+  {
+    size_t operator()(SrtmTile::LatLonKey const & key) const
+    {
+      size_t seed = 0;
+      boost::hash_combine(seed, key.first);
+      boost::hash_combine(seed, key.second);
+      return seed;
+    }
+  };
+
+  using MapT = std::unordered_map<SrtmTile::LatLonKey, SrtmTile, Hash>;
+  MapT m_tiles;
+
+  DISALLOW_COPY(SrtmTileManager);
+};
+}  // namespace generator