Conditional Node Replication based on Connection

Hello !

I’m looking for a way to turn an individual node’s replication off based on a connection-Id check f.e. w/ a callback func. or the nodes variables. Reading the Networking docs it seems Node already has an ‘owner connection’ which might be used for this.

More specifically: While replicating a scene from a headless server to each client, i’d like to have dedicated Nodes replicated only per connection to keep data secret to the connection. Each client’s scene will have one copy of his ‘private’ node replicated.

I can implement this currently via Network-Messages by sending data to the respective connection and setting it on a clients local Node to read, but that would defy the whole point of scene replication and wouldn’t take advantage of vars, attributes and components.

Is there an elegant way to do this w/ the existing API, a network-addon or a simple path forward modifying the Engines replication code ?

tl;dr: I don’t think so. You will have to implement custom networking layer.

long rant: To be honest, I don’t consider Scene Replication (as it is implemented in Urho) a viable solution for multiplayer game. You cannot really customize… anything. The engine either replicates Node “as is” to all clients, or it doesn’t do anything. There’s no filter by connection, no cheap prefab instantiation, no “client-owned” objects. Doesn’t work in some cases, too.

The only published multiplayer game that I know completely discards “scene replication” and uses custom networking system, probably because

Maybe future will prove me wrong, but until then I will treat Urho “scene replication” as… failed academic research that has very little to do with real networking problems.

Eugene,

thank you very much for your insights on current status of network replication, it provides me w/ a guideline on how to proceed + think about partitioning server/client scenes accordingly !

I’m fine w/ having global scene replicated as a constraint and working around it w/ Network-Messages + encapsulating state either in a local Component or Node. It will be sufficient for my usecase. That way it might stay in-line w/ the Scene/Node/Component architecture.

I have no idea about the current state of the art but to my understanding implementing this well and in a performant manner likely needs a way heavier device like a Replication Graph (Replication Graph | Unreal Engine Documentation).

That said, Urho3D is really a pleasure to code with, please keep up the excellent work !

What’s the game? An urho one? Do you recommend anything specific? Just curious.

“Instant War” or something, it’s mobile game.
@rku is it this one?

It was made with Atomic, which is the same as Urho in every way that matters.

Nope, I’m not that good in network programming. Maybe one day I’ll try to find better solution, but it won’t be today