Would someone give a brief explanation of what client and server are? I skimmed over the docs and can’t find any related information. Thanks!
Chenglin
A client is essentially a machine that receives data from the server. The server connects all of the clients by replicating (sending out data to the them).
Check out the link below
Could you be a bit more precise in what you need to know as this question is way to general. Also this is a kind of 1.0.1 concept in Computer Science.
If you don’ t know anything about the Client-Server model I advise you to start here: Client–server model - Wikipedia
Then as LostScout tells you below, learn about UE4 networking basics and multiplayer setup.
As a brief answer, game wise, the server application is responsible for hosting multiple client sessions and run the world logic by its own. It has no renderer as it is not supposed to show anything. The server is highly CPU oriented as it as to handle multiple player actors and sync them together.
On the other side clients are applications that connect to the server and replicates and render the world simulated on the server. The UI for instance only runs on clients as it is a pure client concept.
Thank you zimzimdz! I ask this question because I was looking through the PlatformerGame code and there seemed to be a lot of functions that return a game mode, e.g., GetAuthGameMode() in World.h, GetGameMode() in GameplayStatics.h. I don’t know whether there are other functions that also return game mode , but as for these two, I am confused about how and where they should be used. The GetAuthGameMode() seems related to the server?
But isn’t PlatfomerGame a single player game? If it’s single-player, then why should there be a server? Thanks!
GetAuthGameMode() will only return a valid pointer on a server as the GameMode is only executed (and only exists) on the server. This is mostly for security reason as this module contains some data that you may not want the clients to know about (or a least could potentially have access).
Also why then GetAuthGameMode() for a single player game ? Simply because even in standalone, your game acts as a Listen Server which means you have server and client code running on your local machine.
Here is the GameMode doc:Game Mode and Game State | Unreal Engine Documentation
Here is a definition of what is a Dedicated server, a listen server and a client:
Clients, Dedicated / Listening Server
Finally here is the Client-Server unreal doc:
Client-Server Model | Unreal Engine Documentation
Thank you for the explanation!