Added Traffic Lights from OpenDRIVE.

LibCarla/source/carla/client/TrafficLight.cpp

@@ -11,56 +11,56 @@
 namespace carla {
 namespace client {
 
-void TrafficLight::SetState(rpc::TrafficLightState state) {
+  void TrafficLight::SetState(rpc::TrafficLightState state) {
     GetEpisode().Lock()->SetTrafficLightState(*this, state);
-}
+  }
 
-rpc::TrafficLightState TrafficLight::GetState() const {
+  rpc::TrafficLightState TrafficLight::GetState() const {
     return GetEpisode().Lock()->GetActorSnapshot(*this).state.traffic_light_data.state;
-}
+  }
 
-void TrafficLight::SetGreenTime(float green_time) {
+  void TrafficLight::SetGreenTime(float green_time) {
     GetEpisode().Lock()->SetTrafficLightGreenTime(*this, green_time);
-}
+  }
 
-float TrafficLight::GetGreenTime() const {
+  float TrafficLight::GetGreenTime() const {
     return GetEpisode().Lock()->GetActorSnapshot(*this).state.traffic_light_data.green_time;
-}
+  }
 
-void TrafficLight::SetYellowTime(float yellow_time) {
+  void TrafficLight::SetYellowTime(float yellow_time) {
     GetEpisode().Lock()->SetTrafficLightYellowTime(*this, yellow_time);
-}
+  }
 
-float TrafficLight::GetYellowTime() const {
+  float TrafficLight::GetYellowTime() const {
     return GetEpisode().Lock()->GetActorSnapshot(*this).state.traffic_light_data.yellow_time;
-}
+  }
 
-void TrafficLight::SetRedTime(float red_time) {
+  void TrafficLight::SetRedTime(float red_time) {
     GetEpisode().Lock()->SetTrafficLightRedTime(*this, red_time);
-}
+  }
 
-float TrafficLight::GetRedTime() const {
+  float TrafficLight::GetRedTime() const {
     return GetEpisode().Lock()->GetActorSnapshot(*this).state.traffic_light_data.red_time;
-}
+  }
 
-float TrafficLight::GetElapsedTime() const {
+  float TrafficLight::GetElapsedTime() const {
     return GetEpisode().Lock()->GetActorSnapshot(*this).state.traffic_light_data.elapsed_time;
-}
+  }
 
-void TrafficLight::Freeze(bool freeze) {
+  void TrafficLight::Freeze(bool freeze) {
     GetEpisode().Lock()->FreezeTrafficLight(*this, freeze);
-}
+  }
 
-bool TrafficLight::IsFrozen() const {
+  bool TrafficLight::IsFrozen() const {
     return GetEpisode().Lock()->GetActorSnapshot(*this).state.traffic_light_data.time_is_frozen;
-}
+  }
 
-uint32_t TrafficLight::GetPoleIndex()
-{
+  uint32_t TrafficLight::GetPoleIndex()
+  {
     return GetEpisode().Lock()->GetActorSnapshot(*this).state.traffic_light_data.pole_index;
-}
+  }
 
-std::vector<SharedPtr<TrafficLight>> TrafficLight::GetGroupTrafficLights() {
+  std::vector<SharedPtr<TrafficLight>> TrafficLight::GetGroupTrafficLights() {
     std::vector<SharedPtr<TrafficLight>> result;
     auto ids = GetEpisode().Lock()->GetGroupTrafficLights(*this);
     for (auto id : ids) {
@@ -68,7 +68,7 @@ std::vector<SharedPtr<TrafficLight>> TrafficLight::GetGroupTrafficLights() {
       result.push_back(boost::static_pointer_cast<TrafficLight>(actor));
     }
     return result;
-}
+  }
 
 } // namespace client
 } // namespace carla

LibCarla/source/carla/client/TrafficLight.h

@@ -12,9 +12,9 @@
 namespace carla {
 namespace client {
 
-class TrafficLight : public Actor {
+  class TrafficLight : public Actor {
 
-public:
+  public:
 
     explicit TrafficLight(ActorInitializer init) : Actor(std::move(init)) {}
 
@@ -62,7 +62,7 @@ public:
     /// @note This function calls the simulator
     std::vector<SharedPtr<TrafficLight>> GetGroupTrafficLights();
 
-};
+  };
 
 } // namespace client
 } // namespace carla

LibCarla/source/carla/opendrive/parser/ControllerParser.cpp

@@ -14,7 +14,7 @@ namespace carla {
 namespace opendrive {
 namespace parser {
 
-void ControllerParser::Parse(
+  void ControllerParser::Parse(
       const pugi::xml_document &xml,
       carla::road::MapBuilder &map_builder) {
 
@@ -50,7 +50,7 @@ void ControllerParser::Parse(
       );
     }
 
-}
+  }
 
 } // namespace parser
 } // namespace opendrive

LibCarla/source/carla/road/Controller.h

@@ -14,11 +14,11 @@
 namespace carla {
 namespace road {
 
-class MapBuilder;
+  class MapBuilder;
 
-class Controller : private MovableNonCopyable {
+  class Controller : private MovableNonCopyable {
 
-public:
+  public:
 
     Controller(
         ContId id,
@@ -48,7 +48,7 @@ public:
       return _junctions;
     }
 
-private:
+  private:
 
     friend MapBuilder;
 
@@ -58,7 +58,7 @@ private:
 
     std::set<JuncId> _junctions;
     std::set<SignId> _signals;
-};
+  };
 
 } // namespace road
 } // namespace carla

LibCarla/source/carla/road/MapBuilder.cpp

@@ -769,6 +769,10 @@ namespace road {
         auto it = _map_data._controllers.find(controller);
         DEBUG_ASSERT(it != _map_data._controllers.end());
         it->second->_junctions.insert(junction.first);
+        for(const auto & signal : it->second->_signals) {
+          auto signal_it = _map_data._signals.find(signal);
+          signal_it->second->_controllers.insert(controller);
+        }
       }
     }
   }

LibCarla/source/carla/road/Signal.h

@@ -1,4 +1,4 @@
-// Copyright (c) 2019 Computer Vision Center (CVC) at the Universitat Autonoma
+// Copyright (c) 2020 Computer Vision Center (CVC) at the Universitat Autonoma
 // de Barcelona (UAB).
 //
 // This work is licensed under the terms of the MIT license.
@@ -173,6 +173,10 @@ namespace road {
       return _transform;
     }
 
+    const std::set<ContId>& GetControllers() const {
+      return _controllers;
+    }
+
   private:
     friend MapBuilder;
 

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Traffic/SignComponent.cpp

@@ -1,16 +1,15 @@
-// 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>.
+// Copyright (c) 2020 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 "SignComponent.h"
 
-
-// Sets default values for this component's properties
 USignComponent::USignComponent()
 {
-  // Set this component to be initialized when the game starts, and to be ticked every frame.  You can turn these features
-  // off to improve performance if you don't need them.
   PrimaryComponentTick.bCanEverTick = false;
-
 }
 
 // Called when the game starts
@@ -27,3 +26,12 @@ void USignComponent::TickComponent(float DeltaTime, ELevelTick TickType, FActorC
   Super::TickComponent(DeltaTime, TickType, ThisTickFunction);
 
 }
+
+const FString& USignComponent::GetSignId() const
+{
+  return SignId;
+}
+
+void USignComponent::SetSignId(const FString &Id) {
+  SignId = Id;
+}

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Traffic/SignComponent.h

@@ -1,40 +1,41 @@
-// 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>.
+// Copyright (c) 2020 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 "CoreMinimal.h"
-#include "Components/ActorComponent.h"
+#include "Components/SceneComponent.h"
 #include "Carla/OpenDrive/OpenDrive.h"
 #include "SignComponent.generated.h"
 
 
 UCLASS( ClassGroup=(Custom), meta=(BlueprintSpawnableComponent) )
-class CARLA_API USignComponent : public UActorComponent
+class CARLA_API USignComponent : public USceneComponent
 {
   GENERATED_BODY()
 
 public:
-  // Sets default values for this component's properties
   USignComponent();
 
-  void SetSignId(carla::road::SignId SignId)
-  {
-    Id = SignId;
-  }
+  UFUNCTION(BlueprintPure)
+  const FString &GetSignId() const;
+
+  UFUNCTION(BlueprintCallable)
+  void SetSignId(const FString &Id);
 
 protected:
   // Called when the game starts
   virtual void BeginPlay() override;
 
-public:
   // Called every frame
   virtual void TickComponent(float DeltaTime, ELevelTick TickType, FActorComponentTickFunction* ThisTickFunction) override;
 
-
 private:
-  carla::road::SignId Id;
-
-  FTransform Transform;
 
+  UPROPERTY(Category = "Traffic Sign", EditAnywhere)
+  FString SignId;
 
 };

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Traffic/TrafficLightComponent.cpp

@@ -1,34 +1,71 @@
-// 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>.
+// Copyright (c) 2020 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 "TrafficLightComponent.h"
+#include "Kismet/GameplayStatics.h"
+#include "TrafficLightGroup.h"
+#include "TrafficLightManager.h"
 
-
-// Sets default values for this component's properties
 UTrafficLightComponent::UTrafficLightComponent()
+  : Super()
 {
-  // Set this component to be initialized when the game starts, and to be ticked every frame.  You can turn these features
-  // off to improve performance if you don't need them.
-  PrimaryComponentTick.bCanEverTick = true;
-
-  // ...
 }
 
-
 // Called when the game starts
 void UTrafficLightComponent::BeginPlay()
 {
   Super::BeginPlay();
 
-  // ...
+  // Search the Traffic Light Manager
+  TArray<AActor*> TrafficLightManagerArray;
+  UGameplayStatics::GetAllActorsOfClass(
+      GetWorld(),
+      ATrafficLightManager::StaticClass(),
+      TrafficLightManagerArray);
 
+  // Create it if missing
+  if (!TrafficLightManagerArray.Num())
+  {
+    TrafficLightManagerArray.Add(
+        GetWorld()->SpawnActor<ATrafficLightManager>());
+  }
+
+  // Register this component
+  ATrafficLightManager *TrafficLightManager = Cast<ATrafficLightManager>(TrafficLightManagerArray.Top());
+  TrafficLightManager->RegisterLightComponent(this);
 }
 
-
 // Called every frame
 void UTrafficLightComponent::TickComponent(float DeltaTime, ELevelTick TickType, FActorComponentTickFunction* ThisTickFunction)
 {
   Super::TickComponent(DeltaTime, TickType, ThisTickFunction);
-
   // ...
 }
+
+void UTrafficLightComponent::SetLightState(ETrafficLightState NewState)
+{
+  LightState = NewState;
+  LightChangeDispatcher.Broadcast();
+}
+
+ETrafficLightState UTrafficLightComponent::GetLightState() const
+{
+  return LightState;
+}
+
+void UTrafficLightComponent::SetFrozenGroup(bool InFreeze)
+{
+  if (TrafficLightGroup)
+  {
+    TrafficLightGroup->SetFrozenGroup(InFreeze);
+  }
+}
+
+ATrafficLightGroup* UTrafficLightComponent::GetGroup()
+{
+  return TrafficLightGroup;
+}

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Traffic/TrafficLightComponent.h

@@ -1,14 +1,25 @@
-// 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>.
+// Copyright (c) 2020 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 "CoreMinimal.h"
-#include "Components/ActorComponent.h"
+#include "SignComponent.h"
+#include "TrafficLightState.h"
 #include "TrafficLightComponent.generated.h"
 
+class ATrafficLightManager;
+class ATrafficLightGroup;
 
-UCLASS( ClassGroup=(Custom), meta=(BlueprintSpawnableComponent) )
-class CARLA_API UTrafficLightComponent : public UActorComponent
+// Delegate to define dispatcher
+DECLARE_DYNAMIC_MULTICAST_DELEGATE(FLightChangeDispatcher);
+//DECLARE_DYNAMIC_MULTICAST_DELEGATE_RetVal(ETrafficLightState, FLightChangeDispatcher);
+
+UCLASS(Blueprintable, ClassGroup=(Custom), meta=(BlueprintSpawnableComponent) )
+class CARLA_API UTrafficLightComponent : public USignComponent
 {
   GENERATED_BODY()
 
@@ -16,12 +27,34 @@ public:
   // Sets default values for this component's properties
   UTrafficLightComponent();
 
+  UFUNCTION(BlueprintCallable)
+  void SetLightState(ETrafficLightState NewState);
+
+  UFUNCTION(BlueprintCallable)
+  ETrafficLightState GetLightState() const;
+
+  UFUNCTION(BlueprintCallable)
+  void SetFrozenGroup(bool InFreeze);
+
+  UFUNCTION(BlueprintPure)
+  ATrafficLightGroup* GetGroup();
+
 protected:
   // Called when the game starts
   virtual void BeginPlay() override;
 
-public:
   // Called every frame
   virtual void TickComponent(float DeltaTime, ELevelTick TickType, FActorComponentTickFunction* ThisTickFunction) override;
 
+private:
+
+  friend ATrafficLightManager;
+  UPROPERTY(Category = "Traffic Light", EditAnywhere)
+  ETrafficLightState LightState;
+
+  UPROPERTY(BlueprintAssignable, Category = "Traffic Light")
+  FLightChangeDispatcher LightChangeDispatcher;
+
+  UPROPERTY()
+  ATrafficLightGroup *TrafficLightGroup = nullptr;
 };

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Traffic/TrafficLightController.cpp

@@ -0,0 +1,79 @@
+// Copyright (c) 2020 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 "TrafficLightController.h"
+
+UTrafficLightController::UTrafficLightController()
+{
+
+}
+
+void UTrafficLightController::SetState(TArray<FTrafficLightStage> States)
+{
+  LightStates = States;
+  CurrentState = 0;
+}
+
+const FTrafficLightStage &UTrafficLightController::GetCurrentState() const
+{
+  return LightStates[CurrentState];
+}
+
+float UTrafficLightController::NextState()
+{
+  CurrentState = (CurrentState + 1) % LightStates.Num();
+  SetTrafficLightsState(GetCurrentState().State);
+  return GetCurrentState().Time;
+}
+
+const TArray<UTrafficLightComponent *> &UTrafficLightController::GetTrafficLights()
+{
+  return TrafficLights;
+}
+
+void UTrafficLightController::AddTrafficLight(UTrafficLightComponent * TrafficLight)
+{
+  TrafficLights.Add(TrafficLight);
+}
+
+const FString &UTrafficLightController::GetControllerId() const
+{
+  return ControllerId;
+}
+
+void UTrafficLightController::SetControllerId(const FString &Id)
+{
+  ControllerId = Id;
+}
+
+bool UTrafficLightController::IsCycleFinished() const
+{
+  return CurrentState == (LightStates.Num() - 1);
+}
+
+void UTrafficLightController::SetTrafficLightsState(ETrafficLightState NewState)
+{
+  for(auto *Light : TrafficLights)
+  {
+    Light->SetLightState(NewState);
+  }
+}
+
+int UTrafficLightController::GetSequence() const
+{
+  return Sequence;
+}
+
+void UTrafficLightController::SetSequence(int InSequence)
+{
+  Sequence = InSequence;
+}
+
+void UTrafficLightController::ResetState()
+{
+  CurrentState = (LightStates.Num() - 1);
+  SetTrafficLightsState(GetCurrentState().State);
+}

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Traffic/TrafficLightController.h

@@ -0,0 +1,96 @@
+// Copyright (c) 2020 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 "CoreMinimal.h"
+#include "Object.h"
+#include "TrafficLightState.h"
+#include "TrafficLightComponent.h"
+#include "Containers/Map.h"
+#include "TrafficLightController.generated.h"
+
+// Defines a stage of a semaphor with a State and
+// the time this state lasts
+USTRUCT(BlueprintType)
+struct FTrafficLightStage
+{
+  GENERATED_BODY()
+
+  UPROPERTY(EditAnywhere, BlueprintReadWrite)
+  float Time;
+
+  UPROPERTY(EditAnywhere, BlueprintReadWrite)
+  ETrafficLightState State;
+};
+
+// Maps a controller from OpenDrive.
+// Controls the asociated traffic lights and its cycles
+UCLASS(BlueprintType)
+class CARLA_API UTrafficLightController : public UObject
+{
+  GENERATED_BODY()
+
+public:
+
+  UTrafficLightController();
+
+  UFUNCTION(BlueprintCallable)
+  void SetState(TArray<FTrafficLightStage> States);
+
+  UFUNCTION(BlueprintPure)
+  const FTrafficLightStage &GetCurrentState() const;
+
+  // Updates traffic light components to the next state
+  UFUNCTION(BlueprintCallable)
+  float NextState();
+
+  UFUNCTION(BlueprintPure)
+  const TArray<UTrafficLightComponent *> &GetTrafficLights();
+
+  UFUNCTION(BlueprintPure)
+  const FString &GetControllerId() const;
+
+  UFUNCTION(BlueprintCallable)
+  void SetControllerId(const FString &Id);
+
+  UFUNCTION(BlueprintCallable)
+  void AddTrafficLight(UTrafficLightComponent * TrafficLight);
+
+  UFUNCTION(BlueprintCallable)
+  bool IsCycleFinished() const;
+
+  UFUNCTION(BlueprintCallable)
+  void SetTrafficLightsState(ETrafficLightState NewState);
+
+  UFUNCTION(BlueprintCallable)
+  int GetSequence() const;
+
+  UFUNCTION(BlueprintCallable)
+  void SetSequence(int InSequence);
+
+  UFUNCTION(BlueprintCallable)
+  void ResetState();
+private:
+
+  UPROPERTY(EditAnywhere)
+  FString ControllerId;
+
+  UPROPERTY(EditAnywhere)
+  int CurrentState = 0;
+
+  // Pairs with the state of the semaphors (time - state) e.g. 10s in green
+  UPROPERTY(EditAnywhere)
+  TArray<FTrafficLightStage> LightStates = {
+      {10, ETrafficLightState::Green}, {3, ETrafficLightState::Yellow}, {2, ETrafficLightState::Red}};
+
+  UPROPERTY(EditAnywhere)
+  TArray<UTrafficLightComponent *> TrafficLights;
+
+  // Sequence within junction (unused for now)
+  UPROPERTY(EditAnywhere)
+  int Sequence = 0;
+};

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Traffic/TrafficLightGroup.cpp

@@ -0,0 +1,73 @@
+// Copyright (c) 2020 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.h"
+#include "TrafficLightGroup.h"
+
+
+// Sets default values
+ATrafficLightGroup::ATrafficLightGroup()
+{
+  // Set this actor to call Tick() every frame.  You can turn this off to improve performance if you don't need it.
+  PrimaryActorTick.bCanEverTick = true;
+  SceneComponent = CreateDefaultSubobject<USceneComponent>(TEXT("RootComponent"));
+  RootComponent = SceneComponent;
+}
+
+// Called when the game starts or when spawned
+void ATrafficLightGroup::BeginPlay()
+{
+  Super::BeginPlay();
+
+}
+
+void ATrafficLightGroup::SetFrozenGroup(bool InFreeze)
+{
+  bIsFrozen = InFreeze;
+}
+
+// Called every frame
+void ATrafficLightGroup::Tick(float DeltaTime)
+{
+  Super::Tick(DeltaTime);
+
+  if (bIsFrozen)
+  {
+    return;
+  }
+
+  Timer -= DeltaTime;
+
+  if(Timer <= 0 && Controllers.Num())
+  {
+    NextCycleStep();
+  }
+}
+
+void ATrafficLightGroup::NextCycleStep()
+{
+  UTrafficLightController* controller = Controllers[CurrentController];
+  if (controller->IsCycleFinished())
+  {
+    NextController();
+  }
+  else
+  {
+    Timer = controller->NextState();
+  }
+}
+
+void ATrafficLightGroup::NextController()
+{
+  CurrentController = (CurrentController + 1) % Controllers.Num();
+  UTrafficLightController* controller = Controllers[CurrentController];
+  Timer = controller->NextState();
+}
+
+int ATrafficLightGroup::GetJunctionId() const
+{
+  return JunctionId;
+}

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Traffic/TrafficLightGroup.h

@@ -0,0 +1,72 @@
+// Copyright (c) 2020 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 "CoreMinimal.h"
+#include "GameFramework/Actor.h"
+#include "Components/SceneComponent.h"
+#include "TrafficLightComponent.h"
+#include "TrafficLightController.h"
+#include "TrafficLightGroup.generated.h"
+
+class ATrafficLightManager;
+
+// Class with the logic of semaphors
+UCLASS()
+class CARLA_API ATrafficLightGroup : public AActor
+{
+  GENERATED_BODY()
+
+public:
+  // Sets default values for this actor's properties
+  ATrafficLightGroup();
+
+  UFUNCTION(BlueprintPure)
+  TArray<UTrafficLightController*>& GetControllers() {
+    return Controllers;
+  }
+
+  UFUNCTION(BlueprintCallable)
+  void SetFrozenGroup(bool InFreeze);
+
+  UFUNCTION(BlueprintPure)
+  int GetJunctionId() const;
+
+protected:
+  // Called when the game starts or when spawned
+  virtual void BeginPlay() override;
+
+  // Called every frame
+  virtual void Tick(float DeltaTime) override;
+
+private:
+
+  friend ATrafficLightManager;
+  UPROPERTY(Category = "Traffic Group", VisibleDefaultsOnly, BlueprintReadOnly, meta = (AllowPrivateAccess = "true"))
+  USceneComponent *SceneComponent;
+
+  UPROPERTY(Category = "Traffic Group", EditAnywhere)
+  TArray<UTrafficLightController*> Controllers;
+
+  UPROPERTY()
+  float Timer = 0;
+
+  UPROPERTY()
+  int CurrentController = 0;
+
+  UFUNCTION()
+  void NextCycleStep();
+
+  UFUNCTION()
+  void NextController();
+
+  UPROPERTY(Category = "Traffic Group", EditAnywhere)
+  bool bIsFrozen = false;
+
+  UPROPERTY(Category = "Traffic Group", EditAnywhere)
+  int JunctionId = -1;
+};

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Traffic/TrafficLightManager.cpp

@@ -0,0 +1,116 @@
+// Copyright (c) 2020 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 "TrafficLightManager.h"
+#include "Game/CarlaStatics.h"
+#include <string>
+
+ATrafficLightManager::ATrafficLightManager() {
+  PrimaryActorTick.bCanEverTick = false;
+}
+
+void ATrafficLightManager::RegisterLightComponent(UTrafficLightComponent * TrafficLight) {
+  // Cast to std::string
+  carla::road::SignId SignId(TCHAR_TO_UTF8(*(TrafficLight->GetSignId())));
+
+  // Get OpenDRIVE signal
+  if (GetMap()->GetSignals().count(SignId) == 0)
+  {
+    carla::log_warning("Error: missing signal with id:", SignId);
+    return;
+  }
+  const auto &Signal = GetMap()->GetSignals().at(SignId);
+  if(Signal->GetControllers().empty())
+  {
+    carla::log_warning("Error: no controllers in signal", SignId);
+    return;
+  }
+  // Only one controller per signal
+  auto ControllerId = *(Signal->GetControllers().begin());
+
+  // Get controller
+  const auto &Controller = GetMap()->GetControllers().at(ControllerId);
+  if(Controller->GetJunctions().empty())
+  {
+    carla::log_warning("Error: no junctions in controller", ControllerId);
+    return;
+  }
+  // Get junction of the controller
+  auto JunctionId = *(Controller->GetJunctions().begin());
+
+  // Search/create TrafficGroup (junction traffic light manager)
+  if(!TrafficGroups.Contains(JunctionId))
+  {
+    auto * TrafficLightGroup =
+        GetWorld()->SpawnActor<ATrafficLightGroup>();
+    TrafficLightGroup->JunctionId = JunctionId;
+    TrafficGroups.Add(JunctionId, TrafficLightGroup);
+    carla::log_warning("Spawn TrafficLight Group");
+  }
+  auto * TrafficLightGroup = TrafficGroups[JunctionId];
+
+  // Search/create controller in the junction
+  if(!TrafficControllers.Contains(ControllerId.c_str()))
+  {
+    auto *TrafficLightController = NewObject<UTrafficLightController>();
+    TrafficLightController->SetControllerId(ControllerId.c_str());
+    TrafficLightGroup->GetControllers().Add(TrafficLightController);
+    TrafficControllers.Add(ControllerId.c_str(), TrafficLightController);
+    carla::log_warning("Created Controller");
+  }
+  auto *TrafficLightController = TrafficControllers[ControllerId.c_str()];
+
+  TrafficLight->TrafficLightGroup = TrafficLightGroup;
+
+  // Add signal to controller
+  TrafficLightController->AddTrafficLight(TrafficLight);
+  TrafficLightController->ResetState();
+
+  // Add signal to map
+  TrafficLights.Add(TrafficLight->GetSignId(), TrafficLight);
+}
+
+const boost::optional<carla::road::Map>& ATrafficLightManager::GetMap() {
+  if(!GameMode) {
+    GameMode = UCarlaStatics::GetGameMode(this);
+  }
+  return GameMode->GetMap();
+}
+
+// Called when the game starts
+void ATrafficLightManager::BeginPlay()
+{
+  Super::BeginPlay();
+
+}
+
+ATrafficLightGroup* ATrafficLightManager::GetTrafficGroup(carla::road::JuncId JunctionId)
+{
+  if (TrafficGroups.Contains(JunctionId))
+  {
+    return TrafficGroups[JunctionId];
+  }
+  return nullptr;
+}
+
+
+UTrafficLightController* ATrafficLightManager::GetController(FString ControllerId)
+{
+  if (TrafficControllers.Contains(ControllerId))
+  {
+    return TrafficControllers[ControllerId];
+  }
+  return nullptr;
+}
+
+UTrafficLightComponent* ATrafficLightManager::GetTrafficLight(FString SignId)
+{
+  if (!TrafficLights.Contains(SignId))
+  {
+    return nullptr;
+  }
+  return TrafficLights[SignId];
+}

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Traffic/TrafficLightManager.h

@@ -0,0 +1,60 @@
+// Copyright (c) 2020 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 "TrafficLightComponent.h"
+#include "TrafficLightGroup.h"
+#include "Game/CarlaGameModeBase.h"
+#include "TrafficLightManager.generated.h"
+
+// Class In charge of creating and assigning traffic
+// light groups, controllers and components.
+UCLASS()
+class CARLA_API ATrafficLightManager : public AActor
+{
+  GENERATED_BODY()
+
+public:
+
+  ATrafficLightManager();
+
+  UFUNCTION(BlueprintCallable)
+  void RegisterLightComponent(UTrafficLightComponent * TrafficLight);
+
+  const boost::optional<carla::road::Map> &GetMap();
+
+  UFUNCTION(BlueprintCallable)
+  ATrafficLightGroup* GetTrafficGroup(int JunctionId);
+
+  UFUNCTION(BlueprintCallable)
+  UTrafficLightController* GetController(FString ControllerId);
+
+  UFUNCTION(BlueprintCallable)
+  UTrafficLightComponent* GetTrafficLight(FString SignId);
+
+protected:
+  // Called when the game starts or when spawned
+  virtual void BeginPlay() override;
+
+private:
+
+  // Cached Carla Game Mode
+  UPROPERTY()
+  ACarlaGameModeBase *GameMode = 0;
+
+  // Mapped references to ATrafficLightGroup (junction)
+  UPROPERTY()
+  TMap<int, ATrafficLightGroup *> TrafficGroups;
+
+  // Mapped references to UTrafficLightController (controllers)
+  UPROPERTY()
+  TMap<FString, UTrafficLightController *> TrafficControllers;
+
+  // Mapped references to individual TrafficLightComponents
+  UPROPERTY()
+  TMap<FString, UTrafficLightComponent *> TrafficLights;
+};