Add episode class

LibCarla/source/carla/client/Actor.cpp

@@ -13,25 +13,25 @@ namespace carla {
 namespace client {
 
   geom::Location Actor::GetLocation() const {
-    return GetClientImplementation()->GetActorLocation(*this);
+    return GetEpisode()->GetActorLocation(*this);
   }
 
   geom::Transform Actor::GetTransform() const {
-    return GetClientImplementation()->GetActorTransform(*this);
+    return GetEpisode()->GetActorTransform(*this);
   }
 
   void Actor::SetLocation(const geom::Location &location) {
-    GetClientImplementation()->SetActorLocation(*this, location);
+    GetEpisode()->SetActorLocation(*this, location);
   }
 
   void Actor::SetTransform(const geom::Transform &transform) {
-    GetClientImplementation()->SetActorTransform(*this, transform);
+    GetEpisode()->SetActorTransform(*this, transform);
   }
 
   void Actor::Destroy() {
     if (_is_alive) {
       // Let the exceptions leave the function, IsAlive() will still be true.
-      _is_alive = !GetClientImplementation()->DestroyActor(*this);
+      _is_alive = !GetEpisode()->DestroyActor(*this);
     } else {
       log_warning(
           "attempting to destroy an actor that is already dead:",

LibCarla/source/carla/client/Actor.h

@@ -42,12 +42,6 @@ namespace client {
 
     virtual void Destroy();
 
-  protected:
-
-    auto GetClientImplementation() const {
-      return GetWorld().parent;
-    }
-
   private:
 
     bool _is_alive = true;

LibCarla/source/carla/client/Client.h

@@ -43,7 +43,7 @@ namespace client {
     }
 
     World GetWorld() const {
-      return _client_state->GetWorld();
+      return _client_state->GetCurrentEpisode();
     }
 
   private:

LibCarla/source/carla/client/Sensor.cpp

@@ -28,11 +28,11 @@ namespace client {
     log_debug(GetDisplayId(), ": subscribing to stream");
     if (_is_listening) {
       log_warning(
-          "attempting to listen to stream but sensor is already listeninig:",
+          "attempting to listen to stream but sensor is already listening:",
           GetDisplayId());
       return;
     }
-    GetClientImplementation()->SubscribeToStream(
+    GetEpisode()->SubscribeToStream(
         GetActorDescription().GetStreamToken(),
         std::move(callback));
     _is_listening = true;
@@ -45,7 +45,7 @@ namespace client {
           GetDisplayId());
       return;
     }
-    GetClientImplementation()->UnSubscribeFromStream(
+    GetEpisode()->UnSubscribeFromStream(
         GetActorDescription().GetStreamToken());
     _is_listening = false;
   }

LibCarla/source/carla/client/Vehicle.cpp

@@ -12,13 +12,13 @@ namespace client {
 
   void Vehicle::ApplyControl(const Control &control) {
     if (control != _control) {
-      GetClientImplementation()->ApplyControlToVehicle(*this, control);
+      GetEpisode()->ApplyControlToVehicle(*this, control);
       _control = control;
     }
   }
 
   void Vehicle::SetAutopilot(bool enabled) {
-    GetClientImplementation()->SetVehicleAutopilot(*this, enabled);
+    GetEpisode()->SetVehicleAutopilot(*this, enabled);
   }
 
 } // namespace client

LibCarla/source/carla/client/World.cpp

@@ -17,11 +17,11 @@ namespace carla {
 namespace client {
 
   SharedPtr<BlueprintLibrary> World::GetBlueprintLibrary() const {
-    return parent->GetBlueprintLibrary();
+    return _episode->GetBlueprintLibrary();
   }
 
   SharedPtr<Actor> World::GetSpectator() const {
-    return parent->GetSpectator();
+    return _episode->GetSpectator();
   }
 
   SharedPtr<Actor> World::SpawnActor(
@@ -29,7 +29,7 @@ namespace client {
       const geom::Transform &transform,
       Actor *parent_actor) {
     try {
-      return parent->SpawnActor(blueprint, transform, parent_actor);
+      return _episode->SpawnActor(blueprint, transform, parent_actor);
     } catch (const std::exception &e) {
       log_warning("SpawnActor: failed with:", e.what());
       throw;

LibCarla/source/carla/client/World.h

@@ -7,17 +7,12 @@
 #pragma once
 
 #include "carla/Memory.h"
-#include "carla/client/GarbageCollectionPolicy.h"
+#include "carla/client/detail/Episode.h"
 #include "carla/geom/Transform.h"
 
 namespace carla {
 namespace client {
 
-namespace detail {
-  class Client;
-  class ActorFactory;
-}
-
   class Actor;
   class ActorBlueprint;
   class BlueprintLibrary;
@@ -25,6 +20,8 @@ namespace detail {
   class World {
   public:
 
+    World(detail::Episode episode) : _episode(std::move(episode)) {}
+
     World(const World &) = default;
     World(World &&) = default;
 
@@ -47,13 +44,7 @@ namespace detail {
 
   private:
 
-    friend class Actor;
-    friend class detail::ActorFactory;
-    friend class detail::Client;
-
-    World(SharedPtr<detail::Client> parent) : parent(std::move(parent)) {}
-
-    SharedPtr<detail::Client> parent;
+    detail::Episode _episode;
   };
 
 } // namespace client

LibCarla/source/carla/client/detail/ActorFactory.cpp

@@ -63,17 +63,17 @@ namespace detail {
   }
 
   SharedPtr<Actor> ActorFactory::MakeActor(
-      World world,
+      Episode episode,
       rpc::Actor description,
       GarbageCollectionPolicy gc) {
-    const auto gcw = world.parent->GetGarbageCollectionPolicy();
+    const auto gcw = episode->GetGarbageCollectionPolicy();
     const auto gca = (gc == GarbageCollectionPolicy::Inherit ? gcw : gc);
     if (description.HasAStream()) {
-      return MakeActorImpl<Sensor>(ActorInitializer{description, world}, gca);
+      return MakeActorImpl<Sensor>(ActorInitializer{description, episode}, gca);
     } else if (StringUtil::StartsWith(description.description.id, "vehicle.")) {
-      return MakeActorImpl<Vehicle>(ActorInitializer{description, world}, gca);
+      return MakeActorImpl<Vehicle>(ActorInitializer{description, episode}, gca);
     }
-    return MakeActorImpl<Actor>(ActorInitializer{description, world}, gca);
+    return MakeActorImpl<Actor>(ActorInitializer{description, episode}, gca);
   }
 
 } // namespace detail

LibCarla/source/carla/client/detail/ActorFactory.h

@@ -8,13 +8,13 @@
 
 #include "carla/Memory.h"
 #include "carla/client/GarbageCollectionPolicy.h"
+#include "carla/client/detail/Episode.h"
 #include "carla/rpc/Actor.h"
 
 namespace carla {
 namespace client {
 
   class Actor;
-  class World;
 
 namespace detail {
 
@@ -22,7 +22,7 @@ namespace detail {
   public:
 
     static SharedPtr<Actor> MakeActor(
-        World world,
+        Episode episode,
         rpc::Actor actor_description,
         GarbageCollectionPolicy gc = GarbageCollectionPolicy::Inherit);
   };

LibCarla/source/carla/client/detail/ActorState.h

@@ -30,7 +30,7 @@ namespace detail {
     std::string GetDisplayId() const;
 
     World GetWorld() const {
-      return _parent;
+      return _episode;
     }
 
   protected:
@@ -39,15 +39,23 @@ namespace detail {
       return _description;
     }
 
+    Episode &GetEpisode() {
+      return _episode;
+    }
+
+    const Episode &GetEpisode() const {
+      return _episode;
+    }
+
   private:
 
-    ActorState(rpc::Actor description, World parent)
+    ActorState(rpc::Actor description, Episode episode)
       : _description(std::move(description)),
-        _parent(std::move(parent)) {}
+        _episode(std::move(episode)) {}
 
     rpc::Actor _description;
 
-    World _parent;
+    Episode _episode;
   };
 
 } // namespace detail

LibCarla/source/carla/client/detail/Client.cpp

@@ -12,6 +12,7 @@
 #include "carla/client/Vehicle.h"
 #include "carla/client/World.h"
 #include "carla/client/detail/ActorFactory.h"
+#include "carla/client/detail/Episode.h"
 #include "carla/rpc/Client.h"
 #include "carla/sensor/Deserializer.h"
 #include "carla/streaming/Client.h"
@@ -94,7 +95,7 @@ namespace detail {
   SharedPtr<Actor> Client::GetSpectator() {
     auto spectator = _pimpl->CallAndWait<carla::rpc::Actor>("get_spectator");
     return ActorFactory::MakeActor(
-        GetWorld(),
+        GetCurrentEpisode(),
         spectator,
         GarbageCollectionPolicy::Disabled);
   }
@@ -115,7 +116,7 @@ namespace detail {
           transform,
           blueprint.MakeActorDescription());
     }
-    return ActorFactory::MakeActor(GetWorld(), actor, gc);
+    return ActorFactory::MakeActor(GetCurrentEpisode(), actor, gc);
   }
 
   bool Client::DestroyActor(Actor &actor) {

LibCarla/source/carla/client/detail/Client.h

@@ -10,7 +10,7 @@
 #include "carla/NonCopyable.h"
 #include "carla/Time.h"
 #include "carla/client/GarbageCollectionPolicy.h"
-#include "carla/client/World.h"
+#include "carla/client/detail/Episode.h"
 #include "carla/geom/Transform.h"
 
 #include <functional>
@@ -24,7 +24,7 @@ namespace client {
   class ActorBlueprint;
   class BlueprintLibrary;
   class Vehicle;
-  class World;
+  class Episode;
 }
 namespace rpc { class VehicleControl; }
 namespace sensor { class SensorData; }
@@ -35,6 +35,7 @@ namespace carla {
 namespace client {
 namespace detail {
 
+  /// @todo Make sure this class is really thread-safe.
   class Client
     : public EnableSharedFromThis<Client>,
       private NonCopyable {
@@ -56,10 +57,6 @@ namespace detail {
 
     bool Ping();
 
-    World GetWorld() {
-      return shared_from_this();
-    }
-
     SharedPtr<BlueprintLibrary> GetBlueprintLibrary();
 
     SharedPtr<Actor> GetSpectator();
@@ -94,12 +91,24 @@ namespace detail {
       return _gc_policy;
     }
 
+    size_t GetCurrentEpisodeId() const {
+      return _episode_id;
+    }
+
+    Episode GetCurrentEpisode() {
+      return shared_from_this();
+    }
+
   private:
 
     class Pimpl;
     const std::unique_ptr<Pimpl> _pimpl;
 
     const GarbageCollectionPolicy _gc_policy;
+
+    // At this point the id won't change because we cannot yet restart the
+    // episode from the client.
+    const size_t _episode_id = 0u;
   };
 
 } // namespace detail

LibCarla/source/carla/client/detail/Episode.cpp

@@ -0,0 +1,33 @@
+// Copyright (c) 2017 Computer Vision Center (CVC) at the Universitat Autonoma
+// de Barcelona (UAB).
+//
+// This work is licensed under the terms of the MIT license.
+// For a copy, see <https://opensource.org/licenses/MIT>.
+
+#include "carla/client/detail/Episode.h"
+
+#include "carla/client/detail/Client.h"
+
+#include <exception>
+
+namespace carla {
+namespace client {
+namespace detail {
+
+  Episode::Episode(SharedPtr<PersistentState> state)
+    : _state(std::move(state)),
+      _episode_id(_state->GetCurrentEpisodeId()) {}
+
+  PersistentState &Episode::GetPersistentStateWithChecks() const {
+    DEBUG_ASSERT(_state != nullptr);
+    if (_episode_id != _state->GetCurrentEpisodeId()) {
+      throw std::runtime_error(
+          "trying to access an expired episode; a new episode was started "
+          "in the simulation but an object tried accessing the old one.");
+    }
+    return *_state;
+  }
+
+} // namespace detail
+} // namespace client
+} // namespace carla

LibCarla/source/carla/client/detail/Episode.h

@@ -0,0 +1,43 @@
+// Copyright (c) 2017 Computer Vision Center (CVC) at the Universitat Autonoma
+// de Barcelona (UAB).
+//
+// This work is licensed under the terms of the MIT license.
+// For a copy, see <https://opensource.org/licenses/MIT>.
+
+#pragma once
+
+#include "carla/Debug.h"
+#include "carla/Memory.h"
+#include "carla/client/detail/PersistentState.h"
+
+namespace carla {
+namespace client {
+namespace detail {
+
+  class Episode {
+  public:
+
+    PersistentState &operator*() const {
+      return GetPersistentStateWithChecks();
+    }
+
+    PersistentState *operator->() const {
+      return &GetPersistentStateWithChecks();
+    }
+
+  private:
+
+    friend PersistentState;
+
+    Episode(SharedPtr<PersistentState> state);
+
+    PersistentState &GetPersistentStateWithChecks() const;
+
+    SharedPtr<PersistentState> _state;
+
+    size_t _episode_id;
+  };
+
+} // namespace detail
+} // namespace client
+} // namespace carla

LibCarla/source/carla/client/detail/PersistentState.h

@@ -0,0 +1,23 @@
+// Copyright (c) 2017 Computer Vision Center (CVC) at the Universitat Autonoma
+// de Barcelona (UAB).
+//
+// This work is licensed under the terms of the MIT license.
+// For a copy, see <https://opensource.org/licenses/MIT>.
+
+#pragma once
+
+// #include "carla/client/detail/Client.h"
+
+namespace carla {
+namespace client {
+namespace detail {
+
+  class Client;
+
+  /// At this point the client is the only persistent state we have, but
+  /// conceptually is nice to make the distinction.
+  using PersistentState = Client;
+
+} // namespace detail
+} // namespace client
+} // namespace carla