From e032ae53ada6592ec1dab5adc0d09b71a91f32ad Mon Sep 17 00:00:00 2001
From: bernatx <bernatx@gmail.com>
Date: Thu, 21 Jul 2022 11:37:10 +0200
Subject: [PATCH] Return the merged result of all generated trigger boxes as
 the bounding box of the actor

---
 .../Source/Carla/Traffic/TrafficSignBase.cpp  |  3 +-
 .../Carla/Util/BoundingBoxCalculator.cpp      | 47 +++++++++++++++++++
 .../Source/Carla/Util/BoundingBoxCalculator.h |  3 ++
 3 files changed, 52 insertions(+), 1 deletion(-)

diff --git a/Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Traffic/TrafficSignBase.cpp b/Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Traffic/TrafficSignBase.cpp
index 7568fcaea..215a62870 100644
--- a/Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Traffic/TrafficSignBase.cpp
+++ b/Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Traffic/TrafficSignBase.cpp
@@ -23,11 +23,12 @@ TArray<UBoxComponent*> ATrafficSignBase::GetTriggerVolumes() const
   GetComponents<USignComponent>(Components, false);
   if (Components.Num())
   {
-    USignComponent* SignComponent = Components.Top();
+    USignComponent* SignComponent = Components[0];
     return SignComponent->GetEffectTriggerVolume();
   }
   else
   {
+    UE_LOG(LogCarla, Log, TEXT("returning GetTriggerVolume"));
     TArray<UBoxComponent*> TriggerVolumes;
     TriggerVolumes.Add(GetTriggerVolume());
     return TriggerVolumes;
diff --git a/Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Util/BoundingBoxCalculator.cpp b/Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Util/BoundingBoxCalculator.cpp
index 5d195b209..511803e9d 100644
--- a/Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Util/BoundingBoxCalculator.cpp
+++ b/Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Util/BoundingBoxCalculator.cpp
@@ -74,6 +74,16 @@ FBoundingBox UBoundingBoxCalculator::GetActorBoundingBox(const AActor *Actor, ui
     auto TrafficSign = Cast<ATrafficSignBase>(Actor);
     if (TrafficSign != nullptr)
     {
+      // first return a merge of the generated trigger boxes, if any
+      auto TriggerVolumes = TrafficSign->GetTriggerVolumes();
+      if (TriggerVolumes.Num() > 0)
+      {
+        FBoundingBox Box = UBoundingBoxCalculator::CombineBoxes(TriggerVolumes);
+        FTransform Transform = Actor->GetTransform();
+        Box.Rotation = Transform.InverseTransformRotation(Box.Rotation.Quaternion()).Rotator();
+        return Box;
+      }
+      // try to return the original bounding box
       auto TriggerVolume = TrafficSign->GetTriggerVolume();
       if (TriggerVolume != nullptr)
       {
@@ -610,6 +620,43 @@ FBoundingBox UBoundingBoxCalculator::CombineBBs(const TArray<FBoundingBox>& BBsT
   return {Origin, Extent};
 }
 
+FBoundingBox UBoundingBoxCalculator::CombineBoxes(const TArray<UBoxComponent *>& BBsToCombine)
+{
+  FVector MaxVertex(TNumericLimits<float>::Lowest());
+  FVector MinVertex(TNumericLimits<float>::Max());
+
+  for(const UBoxComponent *BB : BBsToCombine) {
+    auto BoxOrigin = BB->GetComponentLocation();
+    auto BoxExtent = BB->GetScaledBoxExtent();
+    
+    FVector MaxVertexOfBB = BoxOrigin + BoxExtent;
+    FVector MinVertexOfBB = BoxOrigin - BoxExtent;
+
+    MaxVertex.X = (MaxVertexOfBB.X > MaxVertex.X) ? MaxVertexOfBB.X : MaxVertex.X;
+    MaxVertex.Y = (MaxVertexOfBB.Y > MaxVertex.Y) ? MaxVertexOfBB.Y : MaxVertex.Y;
+    MaxVertex.Z = (MaxVertexOfBB.Z > MaxVertex.Z) ? MaxVertexOfBB.Z : MaxVertex.Z;
+    MinVertex.X = (MinVertexOfBB.X < MinVertex.X) ? MinVertexOfBB.X : MinVertex.X;
+    MinVertex.Y = (MinVertexOfBB.Y < MinVertex.Y) ? MinVertexOfBB.Y : MinVertex.Y;
+    MinVertex.Z = (MinVertexOfBB.Z < MinVertex.Z) ? MinVertexOfBB.Z : MinVertex.Z;
+  }
+
+  // Calculate box extent
+  FVector Extent (
+    (MaxVertex.X - MinVertex.X) * 0.5f,
+    (MaxVertex.Y - MinVertex.Y) * 0.5f,
+    (MaxVertex.Z - MinVertex.Z) * 0.5f
+  );
+
+  // Calculate middle point
+  FVector Origin (
+    (MinVertex.X + Extent.X),
+    (MinVertex.Y + Extent.Y),
+    (MinVertex.Z + Extent.Z)
+  );
+
+  return {Origin, Extent};
+}
+
 void UBoundingBoxCalculator::GetMeshCompsFromActorBoundingBox(
   const AActor* Actor,
   const FBoundingBox& InBB,
diff --git a/Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Util/BoundingBoxCalculator.h b/Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Util/BoundingBoxCalculator.h
index 2bcb3875e..82d607054 100644
--- a/Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Util/BoundingBoxCalculator.h
+++ b/Unreal/CarlaUE4/Plugins/Carla/Source/Carla/Util/BoundingBoxCalculator.h
@@ -99,6 +99,9 @@ public:
   UFUNCTION(Category = "Carla Util", BlueprintCallable)
   static FBoundingBox CombineBBs(const TArray<FBoundingBox>& BBsToCombine);
 
+  UFUNCTION(Category = "Carla Util", BlueprintCallable)
+  static FBoundingBox CombineBoxes(const TArray<UBoxComponent *>& BBsToCombine);
+
   // Returns Static Mesh Components that generate the InBB of the Actor
   // ie: the SMComps that creates the BB of the TL light box
   UFUNCTION(Category = "Carla Actor", BlueprintCallable)