Interface NetMulticast function only runs on Server

Development Programming & Scripting C++
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1

It seems to me that interface functions marked as NetMulticast defined in C++ only run on the Server when invoked from the Server.
I made an example:

test_if.h

#pragma once

#include "CoreMinimal.h"
#include "system/utils/log.h"
#include "test_if.generated.h"


UINTERFACE(BlueprintType, NotBlueprintable)
class MEMER2_API UTestIf : public UInterface { GENERATED_BODY() };

class MEMER2_API ITestIf {
	GENERATED_BODY()

public:
	UFUNCTION(BlueprintCallable, NetMulticast, Reliable)
	virtual void do_something();
	virtual void do_something_Implementation() { }
};

test_actor.h

#pragma once

#include "CoreMinimal.h"
#include "test_if.h"
#include "test_actor.generated.h"


UCLASS()
class MEMER2_API ATestActor : public AActor, public ITestIf {
	GENERATED_BODY()

public:
    ATestActor() {
        bReplicates = true;
    }

	virtual void do_something_Implementation() override {
        log_to_screen("Called do_something");
        log_to_screen(FString::Printf(TEXT("%s"), ANSI_TO_TCHAR(HasAuthority() ? "Server" : "Client")));
    }
};

(The cpp-s only include the headers.)

And then i just spawn the actor somewhere where I am certain it gets set up for replication:

image
image991×371 72.9 KB

And the result:
image
image135×120 18.1 KB

(I create 2 actors present both in the listen server and the client.)

So it seems the NetMulticast functions defined in an interface dont get called on clients.
Am I doing something wrong, is this intended behaviour or a bug?

2

ive not tried using MCs on an Interface but more likely the problem is you dont ‘Own’ that actor so you cant call RPCS

3

Doing a multicast on an actor that just spawned might not work as intended, most likely the multicast will not go through. You might as well use the begin play of the actor as replacement.

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