How to make RPC in Unreal Engine Steam Online Subsystem and EOS

Remote Procedure Calls, also known as RPCs, are a way to call something on any other instance. 

In the Unreal Engine, RPCs are used to ship events from the patron to the server, the server to the customer, or from the server to a specific group.

It's important to word that RPCs cannot have a return cost. If you want to return something, you'll ought to use a seconds RPC within the contrary path. There are precise policies that RPCs observe, which are unique in the official Documentation. Some of these regulations encompass wherein the RPC must be run, such as the server instance of an Actor, on the owner of the Actor, or on all instances of the Actor.

There are some necessities for RPCs. First, they must be referred to as on Actors or replicated Subobjects. The Actor (and component) have to additionally be replicated. If the server is looking an RPC to be executed on a customer, handiest the patron who owns that Actor will execute the function. Similarly, if a client is calling an RPC to be performed at the server, the client. ought to very own the Actor that the RPC is being called on.

There is an exception for Multicast RPCs. If they are known as through the server, they will be achieved at the server and on all presently related clients which have an instance of the applicable Actor. However, if they are called from clients, the Multicast will handiest execute domestically and will not execute at the server or different clients.