Using fifo cache for road geometry in routing.

2 files changed, 14 insertions, 10 deletions

diff --git a/routing/geometry.cpp b/routing/geometry.cpp
index 23a41ff4ca..0cb7d20809 100644
--- a/routing/geometry.cpp
+++ b/routing/geometry.cpp
@@ -15,6 +15,10 @@ using namespace std;
 
 namespace
 {
+// @TODO(bykoianko) Consider setting cache size based on available memory.
+// Maximum road geometry cache size in items.
+size_t constexpr kRoadsCacheSize = 5000;
+
 // GeometryLoaderImpl ------------------------------------------------------------------------------
 class GeometryLoaderImpl final : public GeometryLoader
 {
@@ -137,20 +141,21 @@ void RoadGeometry::Load(VehicleModelInterface const & vehicleModel, FeatureType
 }
 
 // Geometry ----------------------------------------------------------------------------------------
-Geometry::Geometry(unique_ptr<GeometryLoader> loader) : m_loader(move(loader))
+Geometry::Geometry(unique_ptr<GeometryLoader> loader)
+    : m_loader(move(loader))
+    , m_featureIdToRoad(make_unique<FifoCache<uint32_t, RoadGeometry>>(
+        kRoadsCacheSize,
+        [this](uint32_t featureId, RoadGeometry & road) { m_loader->Load(featureId, road); }))
 {
   CHECK(m_loader, ());
 }
 
 RoadGeometry const & Geometry::GetRoad(uint32_t featureId)
 {
-  auto const & it = m_roads.find(featureId);
-  if (it != m_roads.cend())
-    return it->second;
+  ASSERT(m_featureIdToRoad, ());
+  ASSERT(m_loader, ());
 
-  RoadGeometry & road = m_roads[featureId];
-  m_loader->Load(featureId, road);
-  return road;
+  return m_featureIdToRoad->GetValue(featureId);
 }
 
 // static
diff --git a/routing/geometry.hpp b/routing/geometry.hpp
index f49343677d..a88dd6d45c 100644
--- a/routing/geometry.hpp
+++ b/routing/geometry.hpp
@@ -11,11 +11,11 @@
 #include "geometry/point2d.hpp"
 
 #include "base/buffer_vector.hpp"
+#include "base/fifo_cache.hpp"
 
 #include <cstdint>
 #include <memory>
 #include <string>
-#include <unordered_map>
 
 namespace routing
 {
@@ -103,8 +103,7 @@ public:
   }
 
 private:
-  // Feature id to RoadGeometry map.
-  std::unordered_map<uint32_t, RoadGeometry> m_roads;
   std::unique_ptr<GeometryLoader> m_loader;
+  std::unique_ptr<FifoCache<uint32_t, RoadGeometry>> m_featureIdToRoad;
 };
 }  // namespace routing