Assigning a Unique ID to a Client Connecting to the Server in Multiplayer

[rosilan]

Hi, I’ve been struggling to understand a particular behavior in Unreal Engine’s multiplayer system. I must admit, I haven’t deeply read the official documentation. I intentionally approach it this way because seeing the solutions Unreal Engine provides for the challenges I face helps me better understand why those solutions are important.

Now, my question is: I want a client to receive a unique ID when connecting to the server. Then, I want the client to reflect this ID on its own UTextRenderComponent. This update should be handled only by the client itself, without the server or other clients being aware of it.

Here's the code I’ve written:

AMyPlayerState.h (not have a constructor)

public:
	FORCEINLINE void SetUniquePlayerID(int32 NewID) { UniquePlayerID = NewID; };

	FORCEINLINE int32 GetUniquePlayerID() const { return UniquePlayerID; };

protected:
	int32 UniquePlayerID = 0;

AMyCharacter.h

private:
	UPROPERTY(EditAnywhere)
	class UTextRenderComponent* PlayerName;

AMyCharacter.cpp

void AMyCharacter::BeginPlay()
{
	Super::BeginPlay();

	if (IsLocallyControlled())
	{
		AMyPlayerState* PS = Cast<AMyPlayerState>(GetPlayerState());
		if (PS && GEngine)
		{
			GEngine->AddOnScreenDebugMessage(-1, 10.f, FColor::Cyan,
				FString::Printf(TEXT("UniquePlayerID: %d \t Name: %s"), PS->GetUniquePlayerID(), *PS->GetName()));
			
			PlayerName->SetText(FText::AsNumber(PS->GetUniquePlayerID()));
		}
	}
}

AMyGameMode.h

protected:
	virtual void PostLogin(APlayerController* NewPlayer) override;
	int32 UniquePlayerID = 0;

AMyGameMode.cpp

AMyGameMode::AMyGameMode()
{
	PlayerStateClass = AMyPlayerState::StaticClass();
}

void AMyGameMode::PostLogin(APlayerController* NewPlayer)
{
	Super::PostLogin(NewPlayer);

	if (NewPlayer && HasAuthority())
	{
		AMyPlayerState* NewPlayerPS = Cast<AMyPlayerState>(NewPlayer->PlayerState);
		if (NewPlayerPS)
		{
			int32 AssignedID = ++UniquePlayerID;
			NewPlayerPS->SetUniquePlayerID(AssignedID);
		}
	}
}

and the output I get:

In the output, the clients know neither about the server nor about the clients. So seeing the default value of UTextRenderComponent is what I expected, and from the server’s point of view, the state of the clients is also what I expected. However, only the server itself seems to have updated UTextRenderComponent. This is something I didn’t expect.

[rosilan]

help pls