Unreal Engine - Collaborative Viewer Template - Multiplayer Functionality

Hey guys. I’ve been working with the collaborative viewer template for the last couple months, I managed to make some blueprints that allow me to both rotate and scale the current hit actor using the BP_TransformComponent.

I’ve been asked to implement multiplayer functionality on my blueprints. The template already comes with multiplayer stuff blueprinted so I basically just copied what code I thought was appropriate.

I managed to make it so that the server can rotate and scale the current hit actor, and it also affects the actor on the client side. However, if the owning client tries to do the same, it doesn’t affect the actor on the server side.

I’m new to multiplayer blueprints so I’ve been watching some tutorials that go over the basics of replication, and I’ve also got some custom events (on top of what came with the template) that should fire the functions over the network.

Has anyone touched on this kind of thing and would be able to give me some pointers?

Thanks in advance :slight_smile:

Actor being modified needs to be set to replicate.
Class defaults → Replication… replicates (true)

If moving the actor, then replicates movement must be ticked.


Replication works Server → Client.
If a client makes a change to an actor or variable said changes will not be replicated.
Server has to make the changes.

So, client hits actor, RPC’s server to attempt a hit. If the server hits it makes the gameplay changes. If the actor modified is set to replicate, then said changes will be replicated across the network.

To maintain server authority the server itself needs to make its determinations of hits etc. You cannot trust the client.

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