Are RPCs working from ActorComponent without setting the ActorComponent to replicates but only the Actor?

Development Programming & Scripting Multiplayer & Networking
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From reading the docs I was under the impression that I have to set bReplicates = true of a component to true in order to send RPCs from it. But could it be that I only need to set it to true if I want to replicate properties, but for RPCs it’s enough that the actor is set to Replicates = true?

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2

If the component is stably-named (i.e, it’s a default subobject of the actor and not created at runtime) - then yes you can send RPC’s to/from that component without it needing to be replicated, so long as the parent actor is replicated.

Note that for components, you should do the following in the constructor:
SetIsReplicatedByDefault(true);

Whereas for actors, you should set the property directly:
bReplicates = true;

The reasoning behind it is silly - but it’s a lesser-known evil.

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3

Thanks for your answer!

But in my case I would actually use SetIsReplicatedByDefault(false); then because I don’t want it to be replicated, right?

In my case I am deactivating/activating this component on the client slightly different than on the server, so I don’t want the replication of bIsActive to happen, but I still want to send RPCs.

I hope this is not something “crazy” to do, is it?

4

That’s fine - don’t forget you can also always just disable property replication on certain properties too, like so:

void UMyComponent::GetLifetimeReplicatedProps(TArray<FLifetimeProperty>& OutLifetimeProps) const
{
	Super::GetLifetimeReplicatedProps(OutLifetimeProps);

	// Disable Unused Properties (Always active + always replicated)
	DISABLE_REPLICATED_PRIVATE_PROPERTY(UActorComponent, bIsActive);
	DISABLE_REPLICATED_PRIVATE_PROPERTY(UActorComponent, bReplicates);
}
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Oh, I did not know that thank you! :slight_smile:

6

Then, dose “CharacterMovementComponent” need to deep coupling with Character any more?

Last time I learn from the document, the reason putting RPCs into the character is to saving the overhead of net guid of CMC…

I wish the movement related stuff could be put back into the CMC itself,
leaving us a loose-coupled character.