Some sensors are forced to be always on the primary server in multi-gpu mode

CHANGELOG.md

@@ -9,6 +9,7 @@
   * Fixed bug causing traffic signals at the end points of a road to sometimes create malformed waypoints.
   * Fixed pedestrian skeleton frame, where sometimes it was draw displaced from the body
   * Fixed decals when importing maps. It was using other .json files found in other packages.
+  * In multi-GPU mode some sensors now are forced to be created on the primary server always (ex. collision sensor)
   * Added the speed limits for 100, 110 and 120 Km/h.
   * Fixing sensor destruction, now the stream and socket is succesfully destroyed.
   * Fixed bug at `Vehicle.get_traffic_light_state()` and `Vehicle.is_at_traffic_light()` causing vehicles to temporarily not lose the information of a traffic light if they moved away from it before it turned green.

PythonAPI/examples/tutorial_gbuffer.py

@@ -95,22 +95,22 @@ def main():
         # Here we will register the callbacks for each gbuffer texture.
         # The function "listen_to_gbuffer" behaves like the regular listen function,
         # but you must first pass it the ID of the desired gbuffer texture.
-        camera.listen_to_gbuffer(carla.GBufferTextureID.SceneColor, lambda image: image.save_to_disk('_out/SceneColor-%06d.png' % image.frame))
-        camera.listen_to_gbuffer(carla.GBufferTextureID.SceneDepth, lambda image: image.save_to_disk('_out/SceneDepth-%06d.png' % image.frame))
-        camera.listen_to_gbuffer(carla.GBufferTextureID.SceneStencil, lambda image: image.save_to_disk('_out/SceneStencil-%06d.png' % image.frame))
-        camera.listen_to_gbuffer(carla.GBufferTextureID.GBufferA, lambda image: image.save_to_disk('_out/GBufferA-%06d.png' % image.frame))
-        camera.listen_to_gbuffer(carla.GBufferTextureID.GBufferB, lambda image: image.save_to_disk('_out/GBufferB-%06d.png' % image.frame))
-        camera.listen_to_gbuffer(carla.GBufferTextureID.GBufferC, lambda image: image.save_to_disk('_out/GBufferC-%06d.png' % image.frame))
-        camera.listen_to_gbuffer(carla.GBufferTextureID.GBufferD, lambda image: image.save_to_disk('_out/GBufferD-%06d.png' % image.frame))
+        camera.listen_to_gbuffer(carla.GBufferTextureID.SceneColor, lambda image: image.save_to_disk('_out/GBuffer-SceneColor-%06d.png' % image.frame))
+        camera.listen_to_gbuffer(carla.GBufferTextureID.SceneDepth, lambda image: image.save_to_disk('_out/GBuffer-SceneDepth-%06d.png' % image.frame))
+        camera.listen_to_gbuffer(carla.GBufferTextureID.SceneStencil, lambda image: image.save_to_disk('_out/GBuffer-SceneStencil-%06d.png' % image.frame))
+        camera.listen_to_gbuffer(carla.GBufferTextureID.GBufferA, lambda image: image.save_to_disk('_out/GBuffer-A-%06d.png' % image.frame))
+        camera.listen_to_gbuffer(carla.GBufferTextureID.GBufferB, lambda image: image.save_to_disk('_out/GBuffer-B-%06d.png' % image.frame))
+        camera.listen_to_gbuffer(carla.GBufferTextureID.GBufferC, lambda image: image.save_to_disk('_out/GBuffer-C-%06d.png' % image.frame))
+        camera.listen_to_gbuffer(carla.GBufferTextureID.GBufferD, lambda image: image.save_to_disk('_out/GBuffer-D-%06d.png' % image.frame))
         # Note that some gbuffer textures may not be available for a particular scene.
         # For example, the textures E and F are likely unavailable in this example,
         # which will result in them being sent as black images.
-        camera.listen_to_gbuffer(carla.GBufferTextureID.GBufferE, lambda image: image.save_to_disk('_out/GBufferE-%06d.png' % image.frame))
-        camera.listen_to_gbuffer(carla.GBufferTextureID.GBufferF, lambda image: image.save_to_disk('_out/GBufferF-%06d.png' % image.frame))
-        camera.listen_to_gbuffer(carla.GBufferTextureID.Velocity, lambda image: image.save_to_disk('_out/Velocity-%06d.png' % image.frame))
-        camera.listen_to_gbuffer(carla.GBufferTextureID.SSAO, lambda image: image.save_to_disk('_out/SSAO-%06d.png' % image.frame))
-        camera.listen_to_gbuffer(carla.GBufferTextureID.CustomDepth, lambda image: image.save_to_disk('_out/CustomDepth-%06d.png' % image.frame))
-        camera.listen_to_gbuffer(carla.GBufferTextureID.CustomStencil, lambda image: image.save_to_disk('_out/CustomStencil-%06d.png' % image.frame))
+        camera.listen_to_gbuffer(carla.GBufferTextureID.GBufferE, lambda image: image.save_to_disk('_out/GBuffer-E-%06d.png' % image.frame))
+        camera.listen_to_gbuffer(carla.GBufferTextureID.GBufferF, lambda image: image.save_to_disk('_out/GBuffer-F-%06d.png' % image.frame))
+        camera.listen_to_gbuffer(carla.GBufferTextureID.Velocity, lambda image: image.save_to_disk('_out/GBuffer-Velocity-%06d.png' % image.frame))
+        camera.listen_to_gbuffer(carla.GBufferTextureID.SSAO, lambda image: image.save_to_disk('_out/GBuffer-SSAO-%06d.png' % image.frame))
+        camera.listen_to_gbuffer(carla.GBufferTextureID.CustomDepth, lambda image: image.save_to_disk('_out/GBuffer-CustomDepth-%06d.png' % image.frame))
+        camera.listen_to_gbuffer(carla.GBufferTextureID.CustomStencil, lambda image: image.save_to_disk('_out/GBuffer-CustomStencil-%06d.png' % image.frame))
 
         time.sleep(10)
 

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

@@ -7,6 +7,7 @@
 #pragma once
 
 #include "Carla.h"
+#include "Carla/Actor/ActorData.h"
 #include "Carla/Actor/ActorRegistry.h"
 
 #include "Carla/Game/Tagger.h"
@@ -14,6 +15,12 @@
 #include "Carla/Util/BoundingBoxCalculator.h"
 #include "Carla/Sensor/Sensor.h"
 
+#include <compiler/disable-ue4-macros.h>
+#include "carla/streaming/Token.h"
+#include "carla/streaming/detail/Token.h"
+#include <compiler/enable-ue4-macros.h>
+
+
 namespace crp = carla::rpc;
 
 FActorRegistry::IdType FActorRegistry::ID_COUNTER = 0u;
@@ -231,3 +238,21 @@ void FActorRegistry::WakeActorUp(FCarlaActor::IdType Id, UCarlaEpisode* CarlaEpi
     WakeActorUp(ChildId, CarlaEpisode);
   }
 }
+
+FString FActorRegistry::GetDescriptionFromStream(carla::streaming::detail::stream_id_type Id)
+{
+  for (auto &Item : ActorDatabase)
+  {
+    // check for a sensor
+    ASensor *Sensor = Cast<ASensor>(Item.Value->GetActor());
+    if (Sensor == nullptr) continue;
+
+    carla::streaming::detail::token_type token(Sensor->GetToken());
+    if (token.get_stream_id() == Id)
+    {
+      const FActorInfo *Info = Item.Value->GetActorInfo();
+      return Info->Description.Id;
+    }
+  }
+  return FString("");
+}

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

@@ -19,16 +19,16 @@
 /// A registry of all the Carla actors.
 class FActorRegistry
 {
-private:
-
-  // using DatabaseType = std::unordered_map<FCarlaActor::IdType, FCarlaActor>;
-  using DatabaseType = TMap<FCarlaActor::IdType, TSharedPtr<FCarlaActor>>;
-
 public:
 
   using IdType = FCarlaActor::IdType;
   using ValueType = TSharedPtr<FCarlaActor>;
 
+private:
+
+  // using DatabaseType = std::unordered_map<IdType, FCarlaActor>;
+  using DatabaseType = TMap<IdType, TSharedPtr<FCarlaActor>>;
+
   // ===========================================================================
   /// @name Actor registry functions
   // ===========================================================================
@@ -90,10 +90,11 @@ public:
     return PtrToId ? FindCarlaActor(*PtrToId) : nullptr;
   }
 
+  FString GetDescriptionFromStream(carla::streaming::detail::stream_id_type Id);
 
-  void PutActorToSleep(FCarlaActor::IdType Id, UCarlaEpisode* CarlaEpisode);
+  void PutActorToSleep(IdType Id, UCarlaEpisode* CarlaEpisode);
 
-  void WakeActorUp(FCarlaActor::IdType Id, UCarlaEpisode* CarlaEpisode);
+  void WakeActorUp(IdType Id, UCarlaEpisode* CarlaEpisode);
 
   /// @}
   // ===========================================================================

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Game/CarlaEpisode.h

@@ -183,6 +183,14 @@ public:
     return ActorDispatcher->GetActorRegistry().FindCarlaActor(Actor);
   }
 
+  /// Get the description of the Carla actor (sensor) using specific stream id.
+  ///
+  /// If the actor is not found returns an empty string
+  FString GetActorDescriptionFromStream(carla::streaming::detail::stream_id_type StreamId)
+  {
+    return ActorDispatcher->GetActorRegistry().GetDescriptionFromStream(StreamId);
+  }
+
   // ===========================================================================
   // -- Actor handling methods -------------------------------------------------
   // ===========================================================================

Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Server/CarlaServer.cpp

@@ -771,14 +771,31 @@ void FCarlaServer::FPimpl::BindActions()
                                  R<carla::streaming::Token>
   {
     REQUIRE_CARLA_EPISODE();
-    if (SecondaryServer->HasClientsConnected() && sensor_id > 1)
+    bool ForceInPrimary = false;
+
+    // check for the world observer (always in primary server)
+    if (sensor_id == 1)
+    {
+      ForceInPrimary = true;
+    }
+
+    // collision sensor always in primary server in multi-gpu
+    FString Desc = Episode->GetActorDescriptionFromStream(sensor_id);
+    if (Desc == "" || Desc == "sensor.other.collision")
+    {
+      ForceInPrimary = true;
+    }
+
+    if (SecondaryServer->HasClientsConnected() && !ForceInPrimary)
     {
       // multi-gpu
+      UE_LOG(LogCarla, Log, TEXT("Sensor %d '%s' created in secondary server"), sensor_id, *Desc);
       return SecondaryServer->GetCommander().SendGetToken(sensor_id);
     }
     else
     {
       // single-gpu
+      UE_LOG(LogCarla, Log, TEXT("Sensor %d '%s' created in primary server"), sensor_id, *Desc);
       return StreamingServer.GetToken(sensor_id);
     }
   };