Client to Server RPC

[ltwlf]

Hey guys,

Thank you for the excellent work on this library! I’m using it for a Unity XR project. XR-real-time requirements differ from those of typical games, so I needed to make a few changes.

Here’s what I’ve done in step 1:

• Implemented a client-to-server RPC system. If ExecuteFlags.ExecuteOnServer is set but code is running on the client, the client will send the RPC to the server.
• Added support for RemoteCallNetSerializable (with compression on the to-do list).

using LiteEntitySystem;
using LiteNetLib.Utils;
using UnityEngine;

namespace Entities
{

    public class GreetingData : INetSerializable
    {
        public string Greeting { get; set; }

        public void Serialize(NetDataWriter writer)
        {
            writer.Put(Greeting);
        }

        public void Deserialize(NetDataReader reader)
        {
            Greeting = reader.GetString();
        }
    }

    public class TestEntity : EntityLogic
    {
        private static RemoteCallNetSerializable<GreetingData> _sendGreeting = new();

        public TestEntity (EntityParams entityParams) : base(entityParams) { }

        protected override void RegisterRPC(ref RPCRegistrator r)
        {
            base.RegisterRPC(ref r);
            r.CreateRPCAction(this, OnReceiveGreeting, ref _sendGreeting, ExecuteFlags.ExecuteOnServer);
        }

        private void OnReceiveGreeting(GreetingData data)
        {
            Debug.Log($"Received Greeting = {data.Greeting}");
        }

        public void SendGreetingToServer()
        {
            if (IsServer) return;

            ExecuteRPC(_sendGreeting, new GreetingData
            {
                Greeting = "Hello from the client!"
            });
        }
    }
}

I’m not entirely sure if I can keep everything in sync long-term, or if you’re open to contributions. I’d love to hear any feedback you might have!

Best, Christian

[RevenantX]

Hi. There is already similar mechanism inside HumanControllerLoigc - SendRequest And SubscribeToClientRequestStruct/SubscribeToClientRequest I will not call this like RPC because it also uses similar technique using ReliableOrdered channel which can be a bit unsynchronized with input sending that uses unreliable.

[ltwlf]

Yes, I saw it. It is tied to the HumanController. I considered to replace or unify it, but for compatibility reason I started with a separate implementation first. In my other PR I made some SyncVar changes. My plan is to bring both together and allow to set sync vars when the client is an owner. I also have request and release ownership calls in my EntityLogic (no PR). You are generally interested in this stuff or should I keep it in my fork? It is hard to keep it synced.

[ltwlf]

What do you suggest?

[RevenantX]

@ltwlf i planned to add more complete Client->Server RPCs. But for stability of game logic and correct prediction/and confirmation they should be included into input packets. And they possibly will be a bit unreliable (when input on server skipped because of long network delay)

[ltwlf]

I understand. I actually would need both reliable and unreliable data channels. In XR, I have to send a large volume of transform data from the client and synchronize it with other clients, and it’s acceptable if some of that data is lost. For the XR Rig/Controllers I user HumanController inputs. And previously, when a user moved an object, I sent that information via unreliable packets, but the routing to all the relevant entities became too cumbersome.

So, you go ahead and implement this yourself, and I'll cancel my PR?

[RevenantX]

I need some time to think, currently i'm a bit busy because of daily work. I will look closer on weekends