Detect when an actor that can interact with the component enters the radius, or leaves it

Source/GameBaseFramework/Private/Interaction/Abilities/GBFGameplayAbility_Interact.cpp

@@ -100,10 +100,43 @@ void UGBFGameplayAbility_Interact::InteractableTargetContext::Reset()
 void UGBFGameplayAbility_Interact::UpdateInteractableOptions( const TArray< UGBFInteractableComponent * > & interactable_components )
 {
     TArray< InteractableTargetInfos > target_infos;
-
     GatherTargetInfos( target_infos, interactable_components );
+
+    typedef TMap< TWeakObjectPtr< AActor >, TWeakObjectPtr< UGBFInteractableComponent > > TActorToComponentMap;
+
+    const auto fill_actor_to_component_map = [ & ]( TActorToComponentMap & map ) {
+        map.Reserve( InteractableTargetContexts.Num() );
+
+        for ( const auto & [ actor, context ] : InteractableTargetContexts )
+        {
+            map.Emplace( actor, context.WidgetInfosHandle.InteractableComponent );
+        }
+    };
+
+    TActorToComponentMap previous_active_targets;
+    fill_actor_to_component_map( previous_active_targets );
+
     ResetUnusedInteractions( target_infos );
     RegisterInteractions( target_infos );
+
+    TActorToComponentMap new_active_targets;
+    fill_actor_to_component_map( new_active_targets );
+
+    for ( const auto & [ actor, component ] : previous_active_targets )
+    {
+        if ( !new_active_targets.Contains( actor ) )
+        {
+            component->OnInteractableActorLeftRadius( GetAvatarActorFromActorInfo() );
+        }
+    }
+
+    for ( const auto & [ actor, component ] : new_active_targets )
+    {
+        if ( !previous_active_targets.Contains( actor ) )
+        {
+            component->OnInteractableActorEnteredRadius( GetAvatarActorFromActorInfo() );
+        }
+    }
 }
 
 void UGBFGameplayAbility_Interact::OnPressCallBack( OptionHandle interaction_option )

Source/GameBaseFramework/Private/Interaction/GBFInteractableComponent.cpp

@@ -38,6 +38,28 @@ void UGBFInteractableComponent::RemoveInteractions()
     InteractionOptionContainer.ResetOptions();
 }
 
+void UGBFInteractableComponent::OnInteractableActorEnteredRadius( AActor * actor )
+{
+    ActorsInInteractionRadius.AddUnique( actor );
+    OnInteractableActorEnteredRadiusDelegate.Broadcast( actor );
+    K2_OnInteractableActorEnteredRadius( actor );
+}
+
+void UGBFInteractableComponent::OnInteractableActorLeftRadius( AActor * actor )
+{
+    ActorsInInteractionRadius.Remove( actor );
+    OnInteractableActorLeftRadiusDelegate.Broadcast( actor );
+    K2_OnInteractableActorLeftRadius( actor );
+}
+
+void UGBFInteractableComponent::K2_OnInteractableActorEnteredRadius_Implementation( AActor * actor )
+{
+}
+
+void UGBFInteractableComponent::K2_OnInteractableActorLeftRadius_Implementation( AActor * actor )
+{
+}
+
 void UGBFInteractableComponent::CustomizeInteractionEventData_Implementation( FGameplayEventData & event_data, FGameplayTag event_tag )
 {
 }

Source/GameBaseFramework/Public/Interaction/GBFInteractableComponent.h

@@ -17,8 +17,13 @@ class GAMEBASEFRAMEWORK_API UGBFInteractableComponent : public UActorComponent
     GENERATED_BODY()
 
 public:
+    DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam( FGBFOnInteractableInteractionRadiusStateChangedDelegate, AActor *, Actor );
+
     UGBFInteractableComponent();
 
+    FGBFOnInteractableInteractionRadiusStateChangedDelegate & OnInteractableActorEnteredRadius();
+    FGBFOnInteractableInteractionRadiusStateChangedDelegate & OnInteractableLeftRadius();
+
     const FGBFInteractionOptionContainer & GetInteractableOptions() const;
     bool IsEnabled() const;
     void SetEnabled( bool enabled );
@@ -35,12 +40,34 @@ class GAMEBASEFRAMEWORK_API UGBFInteractableComponent : public UActorComponent
     UFUNCTION( BlueprintNativeEvent, meta = ( ForceAsFunction ) )
     void CustomizeIndicator( UGBFIndicatorDescriptor * indicator_descriptor, const TArray< FGBFInteractionOption > & options );
 
+    void OnInteractableActorEnteredRadius( AActor * actor );
+    void OnInteractableActorLeftRadius( AActor * actor );
+
+    UFUNCTION( BlueprintPure )
+    bool HasInteractableActorsInRadius() const;
+
+protected:
+    UFUNCTION( BlueprintNativeEvent, DisplayName = "OnInteractableActorEnteredRadius", meta = ( ForceAsFunction ) )
+    void K2_OnInteractableActorEnteredRadius( AActor * actor );
+
+    UFUNCTION( BlueprintNativeEvent, DisplayName = "OnInteractableActorLeftRadius", meta = ( ForceAsFunction ) )
+    void K2_OnInteractableActorLeftRadius( AActor * actor );
+
 private:
     UPROPERTY( EditAnywhere, BlueprintReadOnly, meta = ( AllowPrivateAccess = true ) )
     FGBFInteractionOptionContainer InteractionOptionContainer;
 
     UPROPERTY( EditAnywhere, BlueprintReadWrite, meta = ( AllowPrivateAccess = true ) )
     uint8 bIsEnabled : 1;
+
+    UPROPERTY( BlueprintAssignable, meta = ( AllowPrivateAccess = true ) )
+    FGBFOnInteractableInteractionRadiusStateChangedDelegate OnInteractableActorEnteredRadiusDelegate;
+
+    UPROPERTY( BlueprintAssignable, meta = ( AllowPrivateAccess = true ) )
+    FGBFOnInteractableInteractionRadiusStateChangedDelegate OnInteractableActorLeftRadiusDelegate;
+
+    UPROPERTY()
+    TArray< TObjectPtr< AActor > > ActorsInInteractionRadius;
 };
 
 FORCEINLINE const FGBFInteractionOptionContainer & UGBFInteractableComponent::GetInteractableOptions() const
@@ -56,4 +83,19 @@ FORCEINLINE bool UGBFInteractableComponent::IsEnabled() const
 FORCEINLINE void UGBFInteractableComponent::SetEnabled( bool enabled )
 {
     bIsEnabled = enabled;
+}
+
+FORCEINLINE UGBFInteractableComponent::FGBFOnInteractableInteractionRadiusStateChangedDelegate & UGBFInteractableComponent::OnInteractableActorEnteredRadius()
+{
+    return OnInteractableActorEnteredRadiusDelegate;
+}
+
+FORCEINLINE UGBFInteractableComponent::FGBFOnInteractableInteractionRadiusStateChangedDelegate & UGBFInteractableComponent::OnInteractableLeftRadius()
+{
+    return OnInteractableActorLeftRadiusDelegate;
+}
+
+FORCEINLINE bool UGBFInteractableComponent::HasInteractableActorsInRadius() const
+{
+    return !ActorsInInteractionRadius.IsEmpty();
 }

Source/GameBaseFramework/Public/UI/IndicatorSystem/GBFIndicatorManagerComponent.h

@@ -25,8 +25,8 @@ class GAMEBASEFRAMEWORK_API UGBFIndicatorManagerComponent : public UControllerCo
     UFUNCTION( BlueprintCallable, Category = Indicator )
     void RemoveIndicator( UGBFIndicatorDescriptor * indicator_descriptor );
 
-    DECLARE_EVENT_OneParam( UGBFIndicatorManagerComponent, FIndicatorEvent, UGBFIndicatorDescriptor * descriptor )
-        FIndicatorEvent OnIndicatorAdded;
+    DECLARE_EVENT_OneParam( UGBFIndicatorManagerComponent, FIndicatorEvent, UGBFIndicatorDescriptor * descriptor );
+    FIndicatorEvent OnIndicatorAdded;
     FIndicatorEvent OnIndicatorRemoved;
 
     const TArray< UGBFIndicatorDescriptor * > & GetIndicators() const;