Retrieve sensor definition from static function

LibCarla/source/carla/sensor/CompileTimeTypeMap.h

@@ -32,6 +32,7 @@ namespace detail {
     template <size_t Index>
     struct get_by_index {
       using type = void;
+      using key = void;
     };
   };
 
@@ -64,6 +65,12 @@ namespace detail {
           Value,
           typename CompileTimeTypeMapImpl<Size, Rest...>::template get_by_index<Index>::type
         >::type;
+
+      using key = typename std::conditional<
+          Index == current_index(),
+          Key,
+          typename CompileTimeTypeMapImpl<Size, Rest...>::template get_by_index<Index>::key
+        >::type;
     };
   };
 

LibCarla/source/carla/sensor/SensorRegistry.h

@@ -4,12 +4,19 @@
 // This work is licensed under the terms of the MIT license.
 // For a copy, see <https://opensource.org/licenses/MIT>.
 
-#pragma once
+#ifndef LIBCARLA_SENSOR_REGISTRY_INCLUDE_H
+#define LIBCARLA_SENSOR_REGISTRY_INCLUDE_H
 
 #include "carla/sensor/CompositeSerializer.h"
 
+// =============================================================================
+// Follow the 4 steps to register a new sensor.
+// =============================================================================
+
+// 1. Include the serializer here.
 #include "carla/sensor/s11n/ImageSerializer.h"
 
+// 2. Add a forward-declaration of the sensor here.
 class ADepthCamera;
 class ASceneCaptureCamera;
 class ASemanticSegmentationCamera;
@@ -17,6 +24,9 @@ class ASemanticSegmentationCamera;
 namespace carla {
 namespace sensor {
 
+  // 3. Register the sensor and its serializer in the SensorRegistry.
+
+  /// Contains a registry of all the sensors available.
   using SensorRegistry = CompositeSerializer<
     std::pair<ASceneCaptureCamera *, s11n::ImageSerializer>,
     std::pair<ADepthCamera *, s11n::ImageSerializer>,
@@ -25,3 +35,14 @@ namespace sensor {
 
 } // namespace sensor
 } // namespace carla
+
+#endif // LIBCARLA_SENSOR_REGISTRY_INCLUDE_H
+
+#ifdef LIBCARLA_SENSOR_REGISTRY_WITH_SENSOR_INCLUDES
+
+// 4. Include the sensor here.
+#include "Carla/Sensor/DepthCamera.h"
+#include "Carla/Sensor/SceneCaptureCamera.h"
+#include "Carla/Sensor/SemanticSegmentationCamera.h"
+
+#endif // LIBCARLA_SENSOR_REGISTRY_WITH_SENSOR_INCLUDES

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Actor/ActorBlueprintFunctionLibrary.cpp

@@ -185,14 +185,23 @@ bool UActorBlueprintFunctionLibrary::CheckActorDefinitions(const TArray<FActorDe
 /// -- Helpers to create actor definitions -------------------------------------
 /// ============================================================================
 
+FActorDefinition UActorBlueprintFunctionLibrary::MakeCameraDefinition(
+    const FString &Id)
+{
+  FActorDefinition Definition;
+  bool Success;
+  MakeCameraDefinition(Id, Success, Definition);
+  check(Success);
+  return Definition;
+}
+
 void UActorBlueprintFunctionLibrary::MakeCameraDefinition(
-    const FCameraParameters &Parameters,
+    const FString &Id,
     bool &Success,
     FActorDefinition &Definition)
 {
-  Definition.Id = JoinStrings(TEXT("."), TEXT("sensor"), Parameters.Id).ToLower();
-  Definition.Class = Parameters.Class;
-  Definition.Tags = JoinStrings(TEXT(","), TEXT("sensor"), Parameters.Id).ToLower();
+  Definition.Id = JoinStrings(TEXT("."), TEXT("sensor"), Id).ToLower();
+  Definition.Tags = JoinStrings(TEXT(","), TEXT("sensor"), Id).ToLower();
   // FOV.
   FActorVariation FOV;
   FOV.Id = TEXT("fov");

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Actor/ActorBlueprintFunctionLibrary.h

@@ -13,18 +13,6 @@
 
 #include "ActorBlueprintFunctionLibrary.generated.h"
 
-USTRUCT(BlueprintType)
-struct CARLA_API FCameraParameters
-{
-  GENERATED_BODY()
-
-  UPROPERTY(EditAnywhere, BlueprintReadWrite)
-  FString Id;
-
-  UPROPERTY(EditAnywhere, BlueprintReadWrite)
-  TSubclassOf<AActor> Class;
-};
-
 USTRUCT(BlueprintType)
 struct CARLA_API FVehicleParameters
 {
@@ -73,9 +61,11 @@ public:
   /// ==========================================================================
   /// @{
 
+  static FActorDefinition MakeCameraDefinition(const FString &Id);
+
   UFUNCTION(Category = "Carla Actor", BlueprintCallable)
   static void MakeCameraDefinition(
-      const FCameraParameters &Parameters,
+      const FString &Id,
       bool &Success,
       FActorDefinition &Definition);
 

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Sensor/DepthCamera.h

@@ -18,6 +18,11 @@ class CARLA_API ADepthCamera : public AShaderBasedSensor
 
 public:
 
+  static FActorDefinition GetSensorDefinition()
+  {
+    return UActorBlueprintFunctionLibrary::MakeCameraDefinition(TEXT("depth_camera"));
+  }
+
   ADepthCamera(const FObjectInitializer &ObjectInitializer)
     : Super(ObjectInitializer)
   {

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Sensor/SceneCaptureCamera.h

@@ -18,6 +18,11 @@ class CARLA_API ASceneCaptureCamera : public ASceneCaptureSensor
 
 public:
 
+  static FActorDefinition GetSensorDefinition()
+  {
+    return UActorBlueprintFunctionLibrary::MakeCameraDefinition(TEXT("camera"));
+  }
+
   using ASceneCaptureSensor::EnablePostProcessingEffects;
 
 protected:

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Sensor/SemanticSegmentationCamera.h

@@ -18,6 +18,11 @@ class CARLA_API ASemanticSegmentationCamera : public AShaderBasedSensor
 
 public:
 
+  static FActorDefinition GetSensorDefinition()
+  {
+    return UActorBlueprintFunctionLibrary::MakeCameraDefinition(TEXT("semseg_camera"));
+  }
+
   ASemanticSegmentationCamera(const FObjectInitializer &ObjectInitializer)
     : Super(ObjectInitializer)
   {

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Sensor/SensorFactory.cpp

@@ -10,19 +10,52 @@
 #include "Carla/Actor/ActorBlueprintFunctionLibrary.h"
 #include "Carla/Sensor/SceneCaptureCamera.h"
 
-TArray<FActorDefinition> ADeprecatedSensorFactory::GetDefinitions()
+#include <compiler/disable-ue4-macros.h>
+#include <carla/sensor/SensorRegistry.h>
+#include <compiler/enable-ue4-macros.h>
+#define LIBCARLA_SENSOR_REGISTRY_WITH_SENSOR_INCLUDES
+#include <carla/sensor/SensorRegistry.h>
+#undef LIBCARLA_SENSOR_REGISTRY_WITH_SENSOR_INCLUDES
+
+/// Call GetSensorDefinition() on each sensor registered in the SensorRegistry.
+class FSensorDefinitionGatherer
 {
-  FActorDefinition Cameras;
-  bool Success = false;
-  UActorBlueprintFunctionLibrary::MakeCameraDefinition(
-      {TEXT("camera"), ASceneCaptureCamera::StaticClass()},
-      Success,
-      Cameras);
-  check(Success);
-  return {Cameras};
+  using Registry = carla::sensor::SensorRegistry;
+
+  template <size_t Index>
+  static void Append_impl(TArray<FActorDefinition> &Definitions)
+  {
+    using SensorPtrType = typename Registry::get_by_index<Index>::key;
+    using SensorType = typename std::remove_pointer<SensorPtrType>::type;
+    auto Def = SensorType::GetSensorDefinition();
+    Def.Class = SensorType::StaticClass();
+    Definitions.Add(Def);
+  }
+
+  template <size_t... Is>
+  static void Append_impl(
+      TArray<FActorDefinition> &Definitions,
+      std::index_sequence<Is...>)
+  {
+    std::initializer_list<int> ({(Append_impl<Is>(Definitions), 0)...});
+  }
+
+public:
+
+  static void AppendSensorDefinitions(TArray<FActorDefinition> &Definitions)
+  {
+    Append_impl(Definitions, std::make_index_sequence<Registry::size()>());
+  }
+};
+
+TArray<FActorDefinition> ASensorFactory::GetDefinitions()
+{
+  TArray<FActorDefinition> Definitions;
+  FSensorDefinitionGatherer::AppendSensorDefinitions(Definitions);
+  return Definitions;
 }
 
-FActorSpawnResult ADeprecatedSensorFactory::SpawnActor(
+FActorSpawnResult ASensorFactory::SpawnActor(
     const FTransform &Transform,
     const FActorDescription &Description)
 {
@@ -32,7 +65,8 @@ FActorSpawnResult ADeprecatedSensorFactory::SpawnActor(
   {
     return {};
   }
-  auto *Sensor = World->SpawnActorDeferred<ASceneCaptureCamera>(
+  /// @todo Here we may spawn something else than a scene capture.
+  auto *Sensor = World->SpawnActorDeferred<ASceneCaptureSensor>(
       Description.Class,
       Transform,
       this,

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Sensor/SensorFactory.h

@@ -13,7 +13,7 @@
 
 /// Object in charge of spawning sensors.
 UCLASS()
-class CARLA_API ADeprecatedSensorFactory : public ACarlaActorFactory
+class CARLA_API ASensorFactory : public ACarlaActorFactory
 {
   GENERATED_BODY()