Is it still possible to make replicated UObject in 4.27?

Development Programming & Scripting C++
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1

Hi, I was following this tutorial:

But I can’t get it to work. I can’t call RPC from the UObject. So I wonder, is it still possible to do this? My code looks kinda similar, UObject is exactly the same, and I’m calling its RPC from the Pawn, which is its outer

2

Yes, it works just fine. Check you followed the tutorial completely.

As I said in the article though, I really don’t recommend it. If you already have a Pawn as the outer, just use an Actor Component. Components should be the preference if they are an option, there’s little to no benefit replicating the object.

3

I sit on it like for 2 hours yet, and I can’t figure out, what am I doing wrong:

I have such code:
But when I try to call TestUse its getting called on the server, and TestUse2 it not executed at all. I set owner to my pawn, I set object reference as replicated, I put it into DOREPLIFETIME, but without any satysfying results

UCLASS()
class CCO_API UExtendedObject : public UObject
{
	GENERATED_BODY()
public:
	UFUNCTION(Client, Reliable)
	void TestUse();

	UFUNCTION(Server, Reliable)
	void TestUse2();

	// Allows the Object to get a valid UWorld from it's outer.
	virtual UWorld* GetWorld() const override
	{
		if (const UObject* MyOuter = GetOuter())
		{
			return MyOuter->GetWorld();
		}
		return nullptr;
	}
	
	UFUNCTION(BlueprintPure, Category = "My Object")
	AActor* GetOwningActor() const
	{
		return GetTypedOuter<AActor>();
	}
	
	virtual void GetLifetimeReplicatedProps(TArray<FLifetimeProperty>& OutLifetimeProps) const override
	{
		// Add any Blueprint properties
		// This is not required if you do not want the class to be "Blueprintable"
		if (const UBlueprintGeneratedClass* BPClass = Cast<UBlueprintGeneratedClass>(GetClass()))
		{
			BPClass->GetLifetimeBlueprintReplicationList(OutLifetimeProps);
		}
	}
	
	virtual bool IsSupportedForNetworking() const override
	{
		return true;
	}
	
	virtual int32 GetFunctionCallspace(UFunction* Function, FFrame* Stack) override
	{
		check(GetOuter() != nullptr);
		return GetOuter()->GetFunctionCallspace(Function, Stack);
	}
	
	// Call "Remote" (aka, RPC) functions through the actors NetDriver
	virtual bool CallRemoteFunction(UFunction* Function, void* Parms, struct FOutParmRec* OutParms, FFrame* Stack) override
	{
		check(!HasAnyFlags(RF_ClassDefaultObject));
		AActor* Owner = GetOwningActor();
		UNetDriver* NetDriver = Owner->GetNetDriver();
		if (NetDriver)
		{
			NetDriver->ProcessRemoteFunction(Owner, Function, Parms, OutParms, Stack, this);
			return true;
		}
		return false;
	}
	
	
	/*
	* Optional
	* Since this is a replicated object, typically only the Server should create and destroy these
	* Provide a custom destroy function to ensure these conditions are met.
	*/
	UFUNCTION(BlueprintCallable, BlueprintAuthorityOnly, Category = "My Object")
	void Destroy()
	{
		if (!IsPendingKill())
		{
			checkf(GetOwningActor()->HasAuthority() == true, TEXT("Destroy:: Object does not have authority to destroy itself!"));
			
			OnDestroyed();
			MarkPendingKill();
		}
	}
	
	
protected:
	virtual void OnDestroyed()
	{
		// Notify Owner etc.
	}
};
4

You also need to implement replication at the actor level.

Look at the “Adding to the Subobject List” section.

5

I’ve added ReplicateSubobjects in my pawn, that holds the object, but it still doesn’t work.

virtual bool ReplicateSubobjects(UActorChannel *Channel, FOutBunch *Bunch, FReplicationFlags *RepFlags) override
	{
		bool bWroteSomething = Super::ReplicateSubobjects(Channel, Bunch, RepFlags);
		
		// Single Object
		bWroteSomething |= Channel->ReplicateSubobject(ExtendedObject, *Bunch, *RepFlags);
		
		//bWroteSomething |= Channel->ReplicateSubobjectList(ArrayOfMyObject, *Bunch, *RepFlags);
		
		return bWroteSomething;
	}