multiplayer

[grand stratus]

i will check that

there is another solution i saw , it says to create a function that give the game state reference from game mode using on post login event

calid check dont works

it checks it forever

what i mean it never be valid

[thin stratus]

It should valid eventually

I only ever solved this gracefully with C++

[grand stratus]

what have u done in c++

[thin stratus]

I created a UWorldSubsystem child

And that has a reference to the GameState

And a callback for when that reference is set

And the GameState, on BeginPlay, gets that custom subsystem and sets its reference on it

[long hollow]

can anyone remind me how to fix a jittering sprint animation (replicated) effects client only, obv server is ok. ive checked all the min / max speeds are the same everywhere

[thin stratus]

That way I can query it via the subsystem and if it's not valid listen to the delegate callback

[thin stratus]

When does it jitter? While sprinting or start/stop?

[grand stratus]

okay great

[long hollow]

whjile sprinting

jogging / walking is fine

[thin stratus]

Can you show the code that handles the sprinting?

[stoic ore]

is there a way to simulate that a client gets disconnected to non-dedicated server in PIE?

[long hollow]

sure Exi, 2 secs

https://i.imgur.com/AJvAb7X.png
https://i.imgur.com/P0NPwUx.png
https://i.imgur.com/ZpH65mV.png

[brazen sluice]

In the online subsystem, what are the settings so that find session only finds friend's sessions?
Do I need to disable advertising? Will they still be there?

[thin stratus]

This is a shitty solution

MovementSpeed is a "State"

"States" should always be created as Replicated Variables

You can RPC to the Server

But not RPC to the clients

The Server should set a RepNotify variable with the speed

And that OnRep function should set the maxSpeed on the CMC

[long hollow]

ahh ok well that might explain it then, thanks i'll go fix that 😄

[stoic ore]

null online subsystem has no friends list afaik. What I do to only find friends session is read friends list and search for friend session for every friend in the list.

[brazen sluice]

I'm using steam online subsystem with advanced sessions

[stoic ore]

IOnlineSession has a function "FindFriendSession" you can give friend net id to find a session of them.

[brazen sluice]

But then the server still potentially accept foreigner connections

[thin stratus]

I don't think that's a thing

You could only manually filter them

[brazen sluice]

if someone were to use the command to join one

[thin stratus]

Also #online-subsystems

The only thing you could do is to filter it locally with "is that a friend" and then not show it

And on the Server, when someone connects, doing the same and PreLogin or Login

[brazen sluice]

Really??

[thin stratus]

C++ ahoi

[brazen sluice]

I was assuming that it was a pretty common behaviour

[thin stratus]

Maybe

I honestly don't know, I haven't tried that. Just from what I did in the past, I can't come up with something that would allow this on a Master Server level

[brazen sluice]

I seems weird to me especially since there iss a button "join by presence friend only " on create session

[thin stratus]

You'd need to pass something in to filter

Joining a Session and joining a Server are two different things though

[brazen sluice]

I'd assume some combination would give you friend only sessions

[thin stratus]

The Session is joinable only be friend presece, meaning you can only join via the Friendlist I guess

[brazen sluice]

Yeah

Im assuming so

[thin stratus]

And if you handle your join code correctly it should fail to join the session manually and then also not join the server

But if someone manually joins the server, for whatever reason, they would still be able to join I guess

Just not being part of the session

[stoic ore]

You don't need to filter sessions yourself. Like mentioned, you can just read the friends list and search if the friend has a session.

[brazen sluice]

pre login is a game instance hook?

[thin stratus]

GameMode

C++ only though

Same as Login

BPs only have PostLogin

[brazen sluice]

huuuu

[stoic ore]

anyone? #multiplayer message

[thin stratus]

You mean a Timeout?

[stoic ore]

sure I can implement a timeout for the client but I thought there is maybe something implemented in engine that I can use. Like latency settings or so

or a cvar

[thin stratus]

Was more a question

[grand stratus]

okay since check validity for game state takes so much time , i need to create a function that passes the game state from game mode

so should i make the game state rep notify

or what should i do

[thin stratus]

I don't think that solution would work

The GameMode only exists on the Server

So you would need to send it via the PlayerController or so

And then you still have the issue that sending the RPC with the Reference of the GameState

Cause the GameState isn't magically create by this

It can still be null

[grand stratus]

i was going to send the game state on post login event

[thin stratus]

What would that change though?

Sending Actors via RPCs doesn't create the Actor

It only sends a NetID

afaik

And that would resolve to nothing cause the GameState doesn't exist yet

So same issue

[grand stratus]

so what now

is valid does not work

also if it workd

t

the player state could be still not valid

[thin stratus]

Correct

It's tricky to make this work event based

Without C++ that is

In BPs I would just check on Tick in the Widget if it should update or not

[kindred widget]

I did the 0.0 second delay loop in a couple of places for that.

Dirty. But.. it works. 🤷‍♂️

[grand stratus]

so can i create a blueprint function from c++ as u did @thin stratus

[thin stratus]

Well yeah

[grand stratus]

but i dont know how u did it

so is there a place to study the subsytem thingy

[thin stratus]

Depends on what you mean with study

You can simply inherit from UWorldSubsystem

And the Engine will take care of creating it

It also allows for getting the Subsystem in BP via GetYourSubsystemName

[grand stratus]

i really dont know what i uworldsubsystem

[thin stratus]

A class

If you don't know C++ then this is probably not an option for you

[grand stratus]

i know c++

[thin stratus]

Then create a new C++ class with WorldSubsystem as a Parent

That should be straight forward if you know C++ :<

[grand stratus]

okay i will try to do this

[twin juniper]

hello guys
i want to learn unreal multiplayer using c++.
i made few game using c++ in ue and unity now i want to learn multiplayer

can any one help to find out best tutorials where i can learn what is multiplayer and how to use

[meager spade]

https://learn.unrealengine.com, search youtube, check UDemy, etc.

[fading birch]

Tom Looman has some good multiplayer courses on Udemy as well. They're massively discounted if you're a new UDemy user as well. (So just make a new account in incognito mode if you aren't)

[gilded nest]

I’m creating a game where you have different clans/groups that are creatable and joinable. How would I store this data. Say I created a group, I want the other accounts to be able to search for it and it comes up. How do I do this?

[bitter oriole]

You would put that information over a database with an account system

Something like a publicly available HTTP server with json requests

[fading birch]

please don't ask the same question in multiple channels.

see rule 7

[warm pecan]

Has anyone come across an "off the shelf multi-user (vr?) solution" for Unreal? There's a number for Unity (VRChat, Sinespace, Atlspace) and a few for WebGL (Hubs, FrameVR). Looking to teach classes (so not a game).

[hollow eagle]

If you're looking for a premade game in unreal with those features, you're in the wrong place and possibly the wrong server. This channel is for creating games with multiplayer, not using/finding existing games.

#lounge or another server entirely would be a better place to ask.

If you're asking about having multiple people use unreal at the same time, you're still in the wrong channel but look into "multi user editing"

[boreal wadi]

Has anyone ran into the issue where playing as a client in unreal 5 is pretty much running at 3 frames a second.. How did you fix it. Is UE5 capable of testing multiplayer stuff?

[fading birch]

I would type in stat unit and see what's causing so many issues. I've had no real problems testing multiplayer in UE5

[boreal wadi]

Its not visual. I found the issue. Just need to get help solving it

[mint umbra]

would the gameState be the correct place to initialize the map for an online game?

I want to place actors randomly in the level and need them to replicate to each client

[gilded nest]

I think I would do this differently, maybe in the level, then run a custom event in the player controller that is client sided which gets the actor and it’s transform or vector, prob transform. Either that or run a multicast in the player controller.

[mint umbra]

cool, ill give that a shot.. thank you @gilded nest

[gilded nest]

Yeah no problem

[fading birch]

stat unit doesn't just show visible issues. It shows what's taking a long time to process. My guess is you're doing something on the game thread that you shouldn't be doing.

[tropic snow]

Trying to make a ladder system for multiplayer. This works on server but stutters and doesn't move up on client. Anyone know how to fix this?

[gilded nest]

I suggest making a custom event. Call it whatever, and run it on the client, then create another one that runs on multicast. Put that code in the multicast one, run the multicast from the client event, and put the event on move forward

Make sure if there are any animations they are replicated

I would check on ladder then run the event on true

And false put back to the normal movement

And there should be a class setting I beleive called replicate movement

[inland slate]

Hello everyone,
I upgrade my project from 4.25 to 4.26 and then to 4.27.
After upgrade, i am getting errors on server log (Dedicated server).
Here is link to forum where i have replied to guy who has having same problem,
https://forums.unrealengine.com/t/server-error-could-not-find-outer-particlemodule/245028/2?u=hvs_rhs
If anyone can help.

[rocky kestrel]

I have static mesh component in player and I want to set it realtime (wear helmet) how replicate it?

[past pebble]

Hello I have a custom pawn trying to setup multiplayer, got the movements working but thing is when I add more than one player every others players spawn in the ground with a camera only:

I'm using the default player controller

[dark inlet]

Hello! I have a dedicated server and i would like to display the ping on the player client widget, how can i get the ping variable?

[chrome bay]

You need more playerstarts

[serene sparrow]

Hello.

How bad would it be to have say a couple thousand replicated actors spawn? There is only one replicated property and movement is not replicated.

I realize pre-optimization is bad but I want to have an idea in case it is a horrible thing to do from the get-go.

[chrome bay]

I'll be surprised if they all spawn to be honest, that's a lot to spawn in one go

What's it for - and do they have to be replicated?

[serene sparrow]

I am just spawning some stuff for a gameplay feature. Honestly having them spawn both on server and client separately should be easy-ishly doable, but I wanted to ask first whether there is a common-sense wisdom against doing it the easy way

[chrome bay]

Is this for procedural generation or somesuch?

[serene sparrow]

yes

[chrome bay]

And presumably these actors are somehow network & gameplay relevant, either you want to be able to walk on them or they have collision etc?

[serene sparrow]

yeah. they have overlap and also you can click them

[chrome bay]

I would advise against making them all individually replicated. @winged badger / @meager spade have done some cool things to support deterministic procedural generation without having to replicate each actor individually

Fortnite has a lot of replicated actors but most of them are dormant and loaded with the level

If you have to spawn them at runtime, it gets a lot harder

Without any detail it's hard to say more than that

[serene sparrow]

it's pretty simple procgen so I can do it separately. Just placing some stuff around so that they are different each session. I'll set something up to place them in the same places and do overlap etc. separately with some leeway given to the client.

Or maybe, on another note, if I have a bunch of actors with dormant replication at first, and hidden to the player, I suppose they wouldn't use much resources? I would then activate a random batch each time they are needed.

That way I still have replication for my events etc.*

[chrome bay]

The real issue is that you have to spawn them all with the same deterministic names, then trick the engine into thinking those actors were loaded with the world. Otherwise you have to spawn + replicate each one individually from the server, which is the expensive part. That's what Zlo/Kaos have managed but I don't think there's a specific resource to look at how.

But yeah if they are dormant, they have no network overhead as such - since the channel is closed. Fortnite's entire levels are made up of dormant actors, which are "woke" once they are needed.

[serene sparrow]

What if I have a bunch exist initially, so they are stably named, and then just unhide them and enable replication as needed. My only issue would then be whether 40-50k hidden and not replicated actors produce any slowdown

[chrome bay]

Going to have the same issue, you'd have to wake all the actors you want to change at once to let clients know which ones are visible

Or, alternatively - replicate that information via a proxy actor in a fast array

[serene sparrow]

makes sense, thank you so much for your help! I think I'll take the proxy approach

[past pebble]

Can't I have only one player start for all players ?

[chrome bay]

No because they'll all try to spawn inside each other

The pawn is failing to spawn because of collision, that's why you only get a camera at world origin for all but the first player

[past pebble]

Why does the thirdpersoncharacter works with only one player start ?

[chrome bay]

Might be because the chracters don't block each others' collision

So they'll all just spawn on top of one another

[past pebble]

They spawn like that

[chrome bay]

Maybe they force spawn ignoring collisions

There's a per-actor setting

Either way, it's not the right way to deal with it. They could just as easily spawn underneath the floor doing that

[past pebble]

Ok, so can I spawn the player starts dynamically ? Or should I just add a bunch of them and hope that it'll always work ?

[chrome bay]

add a bunch yeah

Enough for as many players as you want to support

The engines' default implementation doesn't do a very good job of assigning them though

It looks like Pawn.Cpp sets the collision handling method to AdjustIfPossibleButDontSpawnIfColliding in 4.25

That's probably why the character works, because it's auto-adjusting the position

But it likely can't handle that for a large box etc.

[past pebble]

Ok great, thanks

I'm not doing a MMO but how a large multiplayer game would deal with this ?

[chrome bay]

same idea, lots of spawn points

[past pebble]

and then a joining queue based on the number of spawn points availables ?

[chrome bay]

Different ways of doing it, I would just be sure to have enough spawn points to always spawn as many players as you cna have

in UE4, that's only ever going to reach about 100 anyway

You don't have to use playerstarts ofc, you can use your own logic for spawning

[past pebble]

Oh yeah ok!

Really interesting info, thanks mate

[chrome bay]

Really depends on the game ofc

[inland slate]

Any one ?
#multiplayer message

[halcyon totem]

does anyone know the name of the node that has a boolean at the end of it for class components?

v

[elder sable]

Where can i get an event of a player joining a game with full data available ? I tried GameState::AddPlayerState but it seems the player name is not replicated yet

[blissful totem]

GameMode's PostLogin?

[modern cipher]

if you need PlayerState data on the client side you can override OnRep_PlayerState()
Idk if the player state is available OnPostLogin

[elder sable]

Ok thanks !

[rocky kestrel]

I have Player stats component in player where (agility, vitality etc.) are stored then I have function in player which calculates player max health and health depending on those variables. How should I replicate it?

[violet sentinel]

why not HandleStartingNewPlayer ? will save of headache with seamless

[elder sable]

Was that for me ?

[fading birch]

HandleStartingNewPlayer covers both PostLogin and HandleMatchHasStarted. PostLogin isn't triggered on seamless travel, but HandleMatchHasStarted is.

[elder sable]

Oh i guess that's what i need, thanks :p

[fading birch]

just mark the component as replicates?

make sure those variables replicate as well

[lusty sky]

Isn't it the same for something like a player name? it wont change during gameplay i guess?

[rocky kestrel]

Atm my max health and health variables replicates and player stats component replicate.

[fading birch]

It can if you call SetPlayerName

[blissful totem]

Hey when I test my game's networking in editor, the game mode seems to set the match state to "Aborted" shortly after the level loads. Why is it doing this? Is there any way to check?

This happens after the host loads the level. It hits "WaitingToStart", then hits "InProgress" then hits "Aborted. If I Override ReadyToStartMatch to return False, it will shift to Aborted without hitting InProgress

This only happens if the host loads this level from a main menu mode / map.

[warm pecan]

Thks... (I'm always in the wrong place)

[lost dune]

Hello , how to get the local ( owning client ) player character reference ?

getPlayerCharacter(0) don't give me the specific playercharacter from each client

[meager spade]

GameInstance()->GetFirstPlayerController()->GetPawn()

[lost dune]

thank you so much

[meager spade]

don't use those god awful static in multiplayer games

[lost dune]

Oh there isn't in blueprint

what's the equivalent in Blueprints

[patent crystal]

Hell all, running into what is probably a simple problem on some simple p2p functionality. Essentially have a bunch of client's connecting to a host. We want to have some logic for if they somehow get disconnected, to try to find the session again and rejoin. We are running into some issues where, upon trying to re-join the previously cached session, we successfully join, and then lose connection right there after. If we attempt to clear the cached session and run the logic to find the host again and join, we can never find anything.

[2021.09.07-19.23.48:438][105]LogBlueprintUserMessages: [GI_ASCE_C_2147482599] Disconnected with reason: ConnectionLost Trying to rejoin [2021.09.07-19.23.48:438][105]LogBlueprintUserMessages: [GI_ASCE_C_2147482599] Disconnected, Trying to Rejoin... [2021.09.07-19.23.48:438][105]LogOnlineSession: OSS: Join session: traveling to 192.168.1.145:7777 [2021.09.07-19.23.48:438][105]LogBlueprintUserMessages: [GI_ASCE_C_2147482599] Successfully Rejoined! [2021.09.07-19.23.48:451][106]LogNet: Browse: /Game/Maps/LV_Lobby?closed [2021.09.07-19.23.48:451][106]LogNet: Connection failed; returning to Entry

The Join session: ip here is different than the original ip the client uses to get into the host

[lost dune]

Is there a way to get the local player character (possessed locally on the client) using blueprint?

[rich locust]

you can use gamestate playerarray

and filter out with is local controller

[modern cipher]

did you try GetPlayerController()->GetControlledPawn() ?

[lost dune]

No , i'll try

It's the same , it equips the armor piece to the wrong character

...

[modern cipher]

lol getcontrolledpawn returns another pawn reference

wtf?

[lost dune]

because before getcontrolledpawn there is "getPlayercontroller(0)"

the (0) target the first

character

the first controller in this c ase

I can't believe i have issues for getting the simpliest thing in multiplayer

[lost dune]

Or maybe this is because I use separate server with run under one process

Run under one process cam melt the player controller ids?

[plucky prawn]

Is there a "proper" way to make an actor visible to specific players? I tried googling and didn't really find much, but I thought maybe messing around with some of the replication functions might work?

[obsidian rivet]

hey do anybody know that how can i add a system like mini militia i have a multiplayer game but i can not buy the server that is y

[fading birch]

I"m not sure what your question is.

[obsidian rivet]

it is like local multiplayer game in which we can play over bluetooth or wifi hotspot

[rich sinew]

Do you mean not visible to specific players, or not replicate to specific players? they're quite different

[fading birch]

I'm still not clear on what your actual question is. It looks like you hit enter too early or something.

[obsidian rivet]

so it is like local multiplayer

or in this one person is a host whos mobile hotspot is on adn other player are join that match by connecting to that specific wifi and they play the game it is the most demanding game before pubg on playstore i think u might know it

[hollow eagle]

you're asking how to have someone host a server themselves

it's called a listen server and it's supported out of the box

[obsidian rivet]

okay i was asking this as i made a multiplayer game but now the server are too expensive and people say they do not have good quality

[plucky prawn]

Both if possible but mainly visibility. I'm changing my game to spawn spectators server side and I'd like spectators to see each other and also see living players, but have the living players not see the spectators.

[chrome bay]

You can just override IsNetRelevantFor on the spectator class

[plucky prawn]

Thanks. That's what I was looking at doing.

[azure hollow]

hey guys is 85kb too much for a ghost replay? I need to send this to playfab

[woeful pebble]

is using a peer-to-peer server otherwise known as a listen server unsafe if i give my game to my friend?

[azure hollow]

I made JSON serialization because I haven't been able to serialize a struct of array in binary

[woeful pebble]

Like could i get hacked?

[thin stratus]

Eh, what

[woeful pebble]

isn't p2p insecure

[thin stratus]

In what regard

[woeful pebble]

Like i am using a Online subsystem

but

i am still doubting

it

[thin stratus]

It depends on what you mean with insecure

[woeful pebble]

I mean, since i am hosting the server off of my machine won't it mean somebody could get access to my machine?

[thin stratus]

That doesn't really have anything to do with ListenServer or not. Hosting a Dedicated Server on your PC would mean the same

And idk, maybe they can get access, but not more or less than usual.

[woeful pebble]

Okay

[thin stratus]

Also ListenServer is not p2p

p2p means everyone is connected to each other and everyone has authority over their data

Clients are only connected to the ListenServer

So this is not p2p

ListenServer has the Authority and is the Server here

[fair lantern]

Hey guys, im new to unreal

I have this problem where if I play as listen server my traces work fine but if I play in viewport with only clients then I get two traces instead of one

and the second one is in the wrong spot

[blazing spruce]

Hi, does anyone know of a good resource before i start doing some digging into the different types and use cases for different classes, im working on a multiplayer game so i think i need to know about use cases for things like Game Instance, Game Mode, Game State classes even more basic things like what should go in a Character Class compared to a PlayerController class?

[thin stratus]

Pinned Compendium

Second pin or so

Or the video in the first pin too

[blazing spruce]

was that to me?

[empty axle]

yes

[blazing spruce]

sorry, where am i looking?

[empty axle]

on channel pinned messages in top right corner

[blazing spruce]

Legend, cheers!

[upbeat basin]

Is it possible to connect shipped dedicated servers from editor?

[thin stratus]

Visual Studio (or generally the code ide) but not UE4 Editor

[upbeat basin]

Do you mean running the editor from visual studio on development editor mode?

[thin stratus]

No

[upbeat basin]

Attaching the process for debugging?

[thin stratus]

You can Attach Visual Studio to a process

Yeah

[upbeat basin]

Oh okay but that's not what I'm looking for

So it's not possible to connect from PIE, right?

[thin stratus]

Ohhh

You mean Network Connection to play

[upbeat basin]

Yep

[thin stratus]

No you should never connect from the Editor to an outside process

Doesn't matter if shipped or not

[upbeat basin]

I see

I wanted to create a debug environment (dedicated server) to connect from editors so that I can test/debug from editor on different networks and devices

Is it possible to connect the server created by editor on PIE if we're on same local network though?

[hexed pewter]

If I wanted to create a clone of Unreal Tournament, or something like Dota2 (both in very small scale), how much of networking architecture is already there in the engine ready to be used and how much would I need to write from scratch?

[fading birch]

Plenty to make either of those.

[hexed pewter]

I recently looked into CharacterMovementComponent. It has quite a lot of code inside it. Hopefully that does not translate to coding every feature to fit multiplayer.

[bitter oriole]

You should assume that multiplayer support means x5 the code size on average, in my experience

For features like movement, it's more than 10 times

CMC is kinda bloated, but a flying vehicle that behaves perfectly in real world settings is hard to get down to less than 500 - 1000 lines

[hexed pewter]

x5, considering it runs decent with no weird stuttering and sort of that?

[bitter oriole]

Yeah, again, on average. Movement is the worst.

[hexed pewter]

that is really helpfull, I needed to consider this because I'm planning on making a portfolio project, so even a broad assessment is a good thing, again many thanks

[bitter oriole]

If you're not doing a multiplayer development portfolio, MP is likely a bad idea

[hexed pewter]

Indeed I'm not, I'm planning on applying for a junior ue4/c++ programmer job. I just thought having a multiplayer demo would make me stand out more, improving my chances, what was the final straw for making that decision was reading many opinions about "transitioning" already implemented feature from singleplayer to multiplayer and how it can snowball in even not so big games.

[dark edge]

What makes multiplayer movement such a PITA is prediction. If you don't need prediction (the response to input is pretty slow anyway) then movement isn't that hard. Flying is pretty smooth and not too twitchy, you could get away with non-predicted movement.

[grand stratus]

guys if i made a uworld subsystem does it instantiated when i join the level right , cause i want to get the game state to be valid?

[chrome bay]

It won't be valid at the time the subsystem is created, very unlikely anyway

Could arrive at any point, you'll need to code around the race conditions

[grizzled flicker]

Slightly confused by ppl who say root motion is bad for multiplayer. I think I get the logic that if there’s any lag or discrepancy about where the root is of client vs server it can cause big issues but isn’t that the only way to do it? If there’s no root motion then the root of the character won’t move at all so I’d imagine that causes far more issues, no? What don’t I understand ?

[bitter oriole]

You usually have characters moved by their root component, which is a collision capsule

The character skeletal mesh is just for show

Root motion means the mesh goes outside of that root capsule, which is terrible for all the reasons you can think of

[blissful totem]

Where does one store data that can be shared with the server after joining, e.g. player name?

game instance?

[bitter oriole]

Player state

That's where the player name is

Game instance is not replicated

[blissful totem]

thx

[sage isle]

I am looking at server options but I have heard some good and bad things about some, I want to have dedicated servers so I was looking into amazon AWS but what would yall recommend?

[bitter oriole]

Not needing dedicated servers 😬

[modern cipher]

is that timer when using potions in Fortnite
replicated or just a local timer? after x seconds applies a gameplay effect

[summer tide]

How do you replicate a variable in a struct?

[dark edge]

You replicate the whole struct

A struct is basically just a data format, like how a vector is basically just three floats

[summer tide]

The whole thing? What about DOREPSTRUCT?

[bitter oriole]

Only UPROPERTY vars that aren't marked with that "no rep" flag will replicate within the struct

Still needs to be USTRUCT of course and yes, replicated

[summer tide]

So the only way to replicate a single variable in a struct is to replicate the whole struct

[bitter oriole]

No, I just explained what will replicate or not within the struct

[dark edge]

@summer tide are you trying to replicate only certain fields in the struct?

[summer tide]

Right now I only need one of them to be replicated. I don't mind doing the whole struct but trying to understand.

[dark edge]

Ya just replicate the struct.

[bitter oriole]

Replicate the struct, and only replicate relevant fields within it

[summer tide]

thanks

[sacred spire]

Basically, you replicate the Struct + then replicate again the field within it? Extra replication. Am i understand it correctly?

[bitter oriole]

No

Just like UObjects you can only replicate UPROPERTY variables

So a replicated USTRUCT that has no UPROPERTY variable replicates nothing

It's not extra, it's opt-in, per variable

[sacred spire]

Example, once i complete replicated the struct. Then within it has integer variable, bool variable etc, i still have to replicate those 2 variables within it too?

Sorry my brain is horrible

[bitter oriole]

Only UPROPERTYs replicate

That simple

Non UPROPERTY variables don't

[sacred spire]

I see

Thanks

[wheat magnet]

server travel isn't working in editor, but working in standalone, how to fix this issue?

[sage isle]

What would you recommend instead?
I am trying to setup a game where dozens of people can join at any time with a persistent world, wouldnt dedicated servers be the right way to do that or am I going down the wrong road here?

[summer tide]

Do you know if you can use line breaks in multiplayer mode in VS?

[wheat magnet]

it return cast not success

in client side, the cast not working, but cast success in server side, how to fix this

?

[grand stratus]

@chrome bay what do u mean with race condition

[wheat magnet]

can anyone tell how to fix this issue?

[red salmon]

Is there any good tutorial or documentation that can help me with my player rejoin issue so when a player leaves his data is being remembered by the server and when the player rejoins he keeps all the data from before?

[rose raft]

I'm using the NetworkPredictionPlugin. What is the best way to get the duration of time being interpolated (in other words the delta time between the From and To state)?

Here's an example:

// State we are evolving frame to frame and keeping in sync.
struct FExampleSyncState
{
    // ...

      void Interpolate(const FExampleSyncState* From, const FExampleSyncState* To, float Alpha)
    {
        // We have Alpha, which is a value from zero to one.
        // How do we know the amount of time we are interpolating?
    }
}

For more context as to what I'm talking about see this:
https://github.com/EpicGames/UnrealEngine/blob/99b6e203a15d04fc7bbbf554c421a985c1ccb8f1/Engine/Plugins/Runtime/NetworkPredictionExtras/Source/NetworkPredictionExtras/Public/FlyingMovementSimulation.h
An example in that file would be FFlyingMovementSyncState::Interpolate

[vague spruce]

i've got a attribute set on an actor that's replicated. is there any reason i should look into putting this into a player state instead? i don't know what the benefits are of using player state

[steel fractal]

hi everyone, i have a quick question, i made a function to shoot my projectile to the center of the screen, and it runs fine in single player and client to server, but i want to run it on the server to prevent client side cheats. Im wondering why my replication wont work?

[minor sable]

this function gets called by the server would that have something to do with the actor itself possibly and not the function

[steel fractal]

ill try it out

[steel fractal]

wont work unfortunatley

[sinful tree]

Do not do this. If your tick is set to 0.0, you'd effectively be sending an RPC every frame (so every 0.016s at 60FPS) which can flood the network. Marking it reliable means it could further jam the network as each RPC needs verification that it went through.

If you want this function to run on the server, then make it so the client replicates only the state - ie. If they press the fire button, then do the RPC. If you have a gun that you want to repeatedly fire, still do it the same way, but set a timer on the server, and on release of the button, do a second RPC to stop that timer.

[steel fractal]

I see, so your saying the current way I have it is flooding the network and could causing it to not replicate correctly, or at least that it would be terrible for network performance

[coral latch]

Does anyone know where I can learn how to make a dialogue system for couch co-op game?

[fading birch]

Is there a reason you want to build a debug server? a development server generally works fine.

[lost inlet]

And is content being cooked for it?

[fading birch]

Are you sure the functions getting called? I've never seen a server rpc fail to breakpoint.

[lost inlet]

well the standalone configs like game, server, and client usually require cooked content

basically anything that isn't editor

also be interested in the RPC setup

[fading birch]

you could always just launch your server with a custom path and debug it that was with -log -server via your solution config

[lost inlet]

and the _Implementation?

also you don't need to do WithValidation anymore if it's just going to return true

Server_LaunchCharacterRPC_Implementation is probably going to get inlined

by the compiler

it's not been required for ages, the compendium is outdated

no? it getting inlined isn't

but if you have a breakpoint on LaunchCharacterRPC() when compiling DevelopmentEditor, it probably won't hit it

well that should hit, do you see anything in the log about calling an RPC when you're not the owner?

I would assume you're the net owner if it's a character though

you would see it in a play as client PIE session

I forget what the output looks like but it'll include the RPC name

[fading birch]

you could wrap the function with:

#pragma optimize("", off)
void ASideScrollerRPGCharacter::Server_LaunchCharacterRPC_Implementation()
{
    LaunchCharacterRPC();
}
#pragma optimize("", on)``` right @lost inlet ?

[lost inlet]

might as well compile DebugGame Editor if you're going to do that

it doesn't really make as much difference as you probably think it does

well it is because that's how the majority of the in-editor MP verification happens and it's not really failed us yet

and if you do out of process server in the editor then you have to attach the debugger to the other process

ok, fuck it, do UE_LOG

pretty much

probably because you attached to the wrong process

and not really

[vagrant lance]

I have an issue where the host loses input completely after a third client joins the game. Only happens rarely. Any thoughts on what this could be?

I've checked for any 'set input mode ui only' nodes and there are none

[red salmon]

Is there any good tutorial or documentation that can help me with my player rejoin issue so when a player leaves his data is being remembered by the server and when the player rejoins he keeps all the data from before?

[thin stratus]

Not that I know of, but the PlayerState is for that. The GameMode has a setting for how long a PlayerState should be kept alive. And then it's something with the "OverrideWith" function in the PlayerState class, but I'm still confused by the direction of that function and haven't had the chance to look at it since then.

But that only works for a limited time and/or as long the Server isn't shutting down (although I'm not sure you can make an inactive PlayerState live that long)

If it has to remain longer/over a shutdown, you need to save the data on the harddrive of the server

[glad quest]

Hello there. I'm currently trying to read up on Networking in Unreal through eXi's Network Compendium, reached a point where I think I am misunderstanding something though.

I've split my PlayerPawn into Character & Controller and set the Replicating flag on the affected components (Movement etc.). I've moved all input to the player controller and save a reference to the possessed pawn in there.

Then in the Pawn I have the corresponding event run on the server so the client can't cheat

I am unable to move a pawn as client though. Why is that? I expected the server to add the input to the camera / character and send the updated rotation / position back to the client.

[thin stratus]

Because you aren't taking into account that UE4 wants you to set ControlYaw and Input locally :P

You simply can't do what you are doing

Cause the Movement is replicated through the MovementComponent

The Client already sends its data to the Server

And since you aren't setting anything on the Client, it's sending "nothing"

Or rather it's sending that the character is standing still

[glad quest]

Fair enough.

Thank you!

Are there other things UE expects the local client to do? Like Jump?

[thin stratus]

All Input

That causes build-in movement

Jump, Crouch

ControlRotation, MovementInput

And if you do your own, like Sprint, theoretically also that, but that needs your own C++ CMC

[red salmon]

I cant belief that there isnt a solution built in or something out there that doesnt address this problem I kinda looked everywhere and found nothing only this "overridewith" which it kinda sucks. I just want a simple way for the server to identify that player owns that account (steam) and load in his progress that can be saved on a pawn in the world or something close to that

[thin stratus]

Why would it be build in though?

You can identify the Player via their UniqueNetId

Given they have one that is unique

If you use Steam, that ID is the SteamID

GameMode in PreLogin and Login gives the ID.
Or PlayerState has it. All of that is C++ (which is more or less requirement for proper multiplayer projects).

You can, if a player joins, use that ID to figure out where their data is

But if your Server restarts, the data will be lost

And DedicatedServers have to be restarted, best every 24h

So if you don't care about that limitation, put a character somewhere that you can identify by the ID and repossess it when the player rejoins

If you do care about the restart server stuff, save it to the disk, and load it based on the ID.

@red salmon

[red salmon]

many ppl said to not use the unique net it cause it prints out garbage or nothing

tbh I might give that a try I just wanted to do my research before using steam

[thin stratus]

The unique net id is your only chance, unless yo uwant to build your own database

You don't have to print it

But you can

It's just that it's not meant to be printed

But for steam it should give you some string with a number

But if you don't need it in string format, you can just compare the FUniqueNetId type directly

I think the default type of the steam ID is uint64 or so

https://partner.steamgames.com/doc/features/auth

Every Steam user can be uniquely identified by a 64-bit numeric ID, known as the user's Steam ID.

    /** 
     * Platform specific conversion to string representation of data
     *
     * @return data in string form 
     */
    virtual FString ToString() const override
    {
        return FString::Printf(TEXT("%llu"), UniqueNetId);
    }

    /** Holds the net id for a player */
    uint64 UniqueNetId;

That's from FUniqueNetIdSteam

Which you won't touch directly

[glad quest]

Do I assume correctly that Event Dispatchers called by the client won't be replicated to the server since it doesn't own the Dispatchers in the Pawn?

[thin stratus]

EventDispatchers aren't networked to begin with afaik

They call where you call them

That's all

[glad quest]

sigh alright, that's gonna be fun then lmao

[thin stratus]

You have RPCs and OnRep functions in which you can call the Delegate

[glad quest]

I was hoping to be able to re-use part of the infrastructure of the (now SP version. In hindsight, should have thought of MP earlier) which uses Event Dispatchers on Input Level and Actor Components just listen to those

Then the component looks like this

Guess I'll switch to RPCs then

[dark edge]

@glad quest What sort of system are you building where components need to listen for input events like that?

[glad quest]

Crouching etc. are in their own actor components

It was just easier that way

Though the Pawn knows all their components anyway, so I can just call them directly. Not too bad.

Just a bit more untidy if there is more than one component reacting to an event, e.g. Velocity Stop

[glad quest]

Seems to work as intended, nice.

[thin stratus]

That looks like a terrible thing to do with any form of lag :D

[brazen sluice]

Component replication is kind of garbage no? It's kind of random whether something is going to work or not based on the hierarchy of replication and the difference between replication and component replication on the same actor

[modern cipher]

+-------------------+------------+-----------------------+
|                   | Mesh Merge | Master Pose Component |
+-------------------+------------+-----------------------+
| GameThread Cost   | Medium     | Min                   |
+-------------------+------------+-----------------------+
| RenderThread Cost | Low        | High                  |
+-------------------+------------+-----------------------+

which one should be use lol?

[vague fractal]

I'm kinda confused here.
I have a replicated enum variable DodgeDirection.
This variable will decide if the player can go into the dodge animation (Inside of the AnimationBlueprint)

I thought if i just change it on the server it will get replicated so that other players also see the animation, but it doesn't. It will only run on the server 😕

[blissful totem]

Don't try to replicate variables in the animation blueprint

replicate the on the pawn, and have the anim bp grab it from the pawn.

[vague fractal]

That's what i do.
I change the variable via InputBindings

[blissful totem]

So DodgeDirection is replicated on the pawn?

[vague fractal]

More specifically in my custom CMC

[blissful totem]

and on tick you're grabbing dodgedirection and setting it in the anim bp?

[vague fractal]

No, i'm getting the value from a getter which is used in the Transition Rule

Like this here basically

[blissful totem]

ok. can you check to see if the enum is correctly replicating?

If it's not, then the anim bp is not relevant here.

[modern cipher]

IDK about enum replication but if you replicate the state as an int

enum class EMyEnum
{
StateOne = 1,
StateTwo = 2,
}

int32 StateOrWhatever;

then get that int value from the enum

[vague fractal]

Well, i think it isn't correctly replicated, otherwise it should work, i think 😅

[modern cipher]

idk never tried to replicate an enum

[vague fractal]

I think an enum shouldn't change anything.
It's basically just an replicated uint8

[modern cipher]

debug or share code XD i cant say anything more

[vague fractal]

This here are my bindings

    PlayerInputComponent->BindKey(EKeys::W, IE_DoubleClick,  GetPlayerMovementComponent(), &UPlayerMovementComponent::SetDodgeDirection<EDodgeDirection::Forwards>);
    PlayerInputComponent->BindKey(EKeys::S, IE_DoubleClick,  GetPlayerMovementComponent(), &UPlayerMovementComponent::SetDodgeDirection<EDodgeDirection::Backwards>);
    PlayerInputComponent->BindKey(EKeys::D, IE_DoubleClick,  GetPlayerMovementComponent(), &UPlayerMovementComponent::SetDodgeDirection<EDodgeDirection::Right>);
    PlayerInputComponent->BindKey(EKeys::A, IE_DoubleClick,  GetPlayerMovementComponent(), &UPlayerMovementComponent::SetDodgeDirection<EDodgeDirection::Left>);

Where UPlayerMovementComponent::SetDodgeDirection<> is only doing this logic

template<EDodgeDirection DodgeDirection>
void UPlayerMovementComponent::SetDodgeDirection()
{
    if(GetOwner()->HasAuthority())
    {
        return SetDodgeDirection(DodgeDirection);
    }
    Server_SetDodgeDirection(DodgeDirection);
}

The Server_SetDodgeDirection will also just call SetDodgeDirection and it looks like this

void UPlayerMovementComponent::SetDodgeDirection(EDodgeDirection DodgeDirection)
{
    eM_DodgeDirection = CanDodge() ? DodgeDirection : EDodgeDirection::None;
}

eM_DodgeDirection is the replicated enum variable which is also used in my AnimBP

[lusty sky]

hmm what is the purpose of the template? is that function called with different enums?

[vague fractal]

Exactly.
Basically just a way to make it more generic rather than having a method called SetDodgeDirection_Forward, SetDodgeDirection_Right and so on

[lusty sky]

you can have actions bounds to input for left/right.. then call SetDodgeDirection( EnumDirection )

I dont think you can replicate enum class
try to change that to the old type TEnumAsByte or use an int instead to replicate the enum value

[obsidian rivet]

hey i want to ask something did any one ever played mini militia

[vague fractal]

Welp, i gonna give it a try without enum class, but i would be shocked if you really can't do that

I've tried it now with a plain int32, but it's the same result

[glad quest]

How come?

[lusty sky]

@vague fractal i tried it with TEnumAsByte and it worked

[lost inlet]

mesh merge having a "medium" gamethread cost is a little bit disingenuous because while there is a medium impact to perform the merge, you do save on not having to update child transforms

[modern cipher]

i wonder what fortnite uses to handle clothing on modular meshes

high render cost for multiplayer is kinda bad i guess

[lusty sky]

UENUM(BlueprintType)
enum MyEnum 
{
Default  =   0,
Yes      = 100,
No       = 250,
};

UPROPERTY(Replicated, BlueprintReadOnly, Category = Test)
TEnumAsByte<MyEnum> MyValue;

you should have a default entry value = 0

@vague fractal

[thin stratus]

Because movement will only be smooth for the local client if you use C++ and your own child class of the CMC

You are only setting Sprinting on the Server, and then replicate it down to the client again

Not only is that a small delay before the client actually notices teh sprint

but it will also cause corrections since the CMC will now move the character differently on client and server for a few frames

[glad quest]

Yeah, you're right, I just tested with simulated worse network conditions. Ouch.

[glad quest]

It is probably even worse than just that, since we used an additive approach for components where each component would be responsible for calculating it's own influence (speed, rotation) and they get combined in the core.

[thin stratus]

RIP

Movement Replication is heavily bound to the CharacterMovementComponent

[glad quest]

Guess we won't get around making a custom solution for this then.

time to rewrite the entire thing in C++

[fluid summit]

Is "Executes on owning client" safe or is it the same as running it on the remote without replication? i read about what it's but i'm not sure if there's a diference

Player --> Hey server, run this on me with the current state you have of my self
Or
Player --> Hey server, run this on me with the current state that I have of my self

[blissful totem]

The server would be telling the client to do something with its current state

[fluid summit]

Oh that makes sense, i'm gonna check it to run on server and change the replication relevancy of the object to "only relevant to owner" then

[fluid summit]

I'm spawning a placeholder actor on the remote, so when you click, it checks against the server if there's collisions with other actors (dedi server)
that way i can move the placeholder actor freely on the remote without having to update it's position on the server.
Does anyone can think of a better way to implement this?

[vagrant lance]

Is there a 'proper' way for players spawning their own characters? I've been doing it through the player controller on a 'On Server RPC' but that's throwing up some rare issues where Possession doesn't work

[red salmon]

Thank you for the information about the unique player ID it works, although I wonder can the unique net ID be tampered with locally?

[vague fractal]

@lusty sky The problem was actually just me here.
I've forgot to replicate the custom CMC 🤦‍♀️

[twin juniper]

affordable fixed pricing cloud suggestions? I'm planning out a third person MVP and wonder what suggestions you have to host the dedicated server. I been looking at DigitalOcean droplet's and they seem to be ideal for the MVP stage. Any insight, has anyone used droplets for their projects? o:

[fading birch]

I've used AWS Gamelift before. Which is basically some preconfigured EC2 instances. It can get pretty pricey. I've used DO for hosting servers for private testing events and it seems alright for stuff like that.

[limber gyro]

im using playfab, they give you 1 server for free and is by far the easiest one i found to implement

[twin juniper]

that's great to hear, exactly what I want, testing MVP. AWS Gamelift seems rad to try out if the MVP is successful

[twin juniper]

never heard of playfab before, will check it out. thanks 🙏

[quasi tide]

Is there a way to see which client ran the server event?

[vivid seal]

@limber gyro i tried to figure out how to get playfab working but am apparently too dumb, any specific resources you used to get it set up?

[harsh lintel]

I have a targeting system, it rotates the player that is targeting something, to get the new rotation of the character that is targeting something it does this ```FRotator UTargetSystemComponent::GetControlRotationOnTarget(AActor* OtherActor) const
{
const FRotator ControlRotation = PlayerController->GetControlRotation();

const FVector CharacterLocation = CharacterReference->GetActorLocation();
const FVector OtherActorLocation = OtherActor->GetActorLocation();

// Find look at rotation
const FRotator LookRotation = FRotationMatrix::MakeFromX(OtherActorLocation - CharacterLocation).Rotator();
float Pitch = LookRotation.Pitch;
FRotator TargetRotation;
if (bAdjustPitchBasedOnDistanceToTarget)
{
    const float DistanceToTarget = GetDistanceFromCharacter(OtherActor);
    const float PitchInRange = (DistanceToTarget * PitchDistanceCoefficient + PitchDistanceOffset) * -1.0f;
    const float PitchOffset = FMath::Clamp(PitchInRange, PitchMin, PitchMax);

    Pitch = Pitch + PitchOffset;
    TargetRotation = FRotator(Pitch, LookRotation.Yaw, ControlRotation.Roll);
}
else
{
    if (bIgnoreLookInput) {
        TargetRotation = FRotator(Pitch, LookRotation.Yaw, ControlRotation.Roll);
    } else {
        TargetRotation = FRotator(ControlRotation.Pitch, LookRotation.Yaw, ControlRotation.Roll);
    }
}

return FMath::RInterpTo( ControlRotation, TargetRotation, GetWorld()->GetDeltaSeconds(), 9.0f );

}

and then with the return of that I just call ```        PlayerController->SetControlRotation(ControlRotation);

But the rotation doesn't look smooth, any ideas how to improve it?

[fading birch]

They have a getting started guide for ue4. I would check that.

Or just do some googling. Plenty of tuts

[tame adder]

can anyone here help me? im trying to do command servertravel to a new map with the clients already in a created session when the map loads the host loads in but the others disconnect from the map?

[fading birch]

I would look into beacons. It's a lightweight object you can send to the server ahead of time.

[tame adder]

beacons i have never heard of that befreo

[cedar tangle]

I am so happy to discover the "Blueprint Type: Interface".

[fading birch]

There's a pin in #online-subsystems about them.

[vivid seal]

looking at ShooterGame's implementation of confirming hitscan shots, am I correct that unreal doesn't do any kind of rewinding or compensating for latency for shooting? It just checks whether the shot was possible given the server's current location/rotation of the shooter and the hit actor? is this because CMC is already doing extrapolation, so clients are not shooting at "past" versions of other players, but predicted versions of them? Or is this just assuming that latency will be covered by the leeway given to the bounding box?

also on top of that it seems like the server accepts the client's spread value instead of calculating its own, but this would definitely be open to exploits i think since the spread value is just used to give the server a "possible" radius the shot could have been in

[vivid seal]

i really dont want to implement server rewinding and have animations playing on the server so i'd like to use this "trust the client but with some sanity checks" approach but am just wondering if the sanity checks in ShooterGame are about what is normal or if it's a simplified example and I'd need something more complicated.

[thin stratus]

Hm, good questions. Not sure what Shooter Game does exactly, cause I haven't looked at that part of its code yet. Have you had a look at the UT source code, just in case it does things differently or more advanced? @vivid seal

[azure hollow]

best way to compress a structure?

[limber gyro]

i just followed the docs on their site, if you do exactly what they tell you to do, you will be fine

i did strugle a bit in the beggining because i tried to do things in the game mode instead of the game module

[quasi tide]

2 questions that kind of surround the same thing:

1. How do you actually set the owner to the correct client? I have the weapon set to replicate, and in the begin play, have the spawning behind a HasAuthority check. If they have authority, then they can spawn the weapon. So, initially, the server should be the only thing spawning the weapon, then replicating it to the clients. In this scenario, I was setting the owner to self, and that worked initially, but it no longer does, and I'm not sure why.

2. A client is trying to pick up an item and place it in their inventory. When the client goes to interact with the item, it calls a RunOnServer event to pick the item up. Server then calls a RunOnOwningClient event to have the client add it to their inventory. But this never happens. I have confirmed that my inventory works in a non-networked setup. So, I thought it might be an ownership issue, but I'm not sure how I can find which client is requesting the pickup in order to set the owner to be that client.

[floral crow]

Are you setting the owner on the SpawnActor node?

[quasi tide]

Yes.

It is what is behind the authority check

[thin stratus]

In a Character?

I heard mixed things about doing that. Try moving the code to OnPossessed

And then if it still doesn't work, combine that with using the Controller of the Character as Owner

[quasi tide]

Yeah, the weapon spawning is in the character, as is the pickup logic

[thin stratus]

2. A client is trying to pick up an item and place it in their inventory. When the client goes to interact with the item, it calls a RunOnServer event to pick the item up. Server then calls a RunOnOwningClient event to have the client add it to their inventory. But this never happens. I have confirmed that my inventory works in a non-networked setup. So, I thought it might be an ownership issue, but I'm not sure how I can find which client is requesting the pickup in order to set the owner to be that client.
   Also this sounds like a broken setup

The Server should not need to RPC back the "Put into Inventory"

The Server is the authority over the Inventory

If at all they should send some reduced amount of data (everything needed to display it) back

[vague fractal]

How should someone properly replicate a LaunchCharacter ?
Currently i'm only doing that on the server and the result is also how it should if the client is also the server, but a normal client will have strong corrections.
Is the solution here to also call the LaunchCharacter on the client here ?

[quasi tide]

The inventory is a component on the character, if the client owns the character through the PC - don't they also own the inventory component?

[thin stratus]

And yeah, if you call the ClientRPC on the Item itself or similar, it's gonna be dropped. The Item is probably not owned by the Client

Yeah

Is the Inventory Component marked as replicated?

[quasi tide]

ClientRPC is not on the item, it is on the character.

[thin stratus]

Can't really sync that

The Server corrects you cause the timestamp that they move you with has a different location result

You can only get that into sync by implementing whatever movement you are doing into the CMC

And only if the Client is the one instigating it

[quasi tide]

Not that I recall. I didn't do that because I was trying to have the client add the item to the inventory on their own. (Yeah, I know, don't trust the client)

[thin stratus]

You shouldn't do that either way

The Server would never know about the inventory

At that point you could just not tell the server at all

[quasi tide]

That's fair

[vague fractal]

The LaunchCharacter is actually be called in my custom CMC, but i guess i have to do this with the rather complicated way where you use those bit flags ?

[thin stratus]

If it's triggered via input of the player,. yeah

[azure hollow]

is 90kb heavy file to send to the server for a ghost replay?

[vague fractal]

Really wish it would be less complicated >_<
But guess it's time to try it again

[quasi tide]

Alright - so, in summary:

For issue 1 - try spawning and attaching the weapon through the player controller OnPossess
Issue 2 - Replicate the inventory component, but only add the item on the server side, then it'll be replicated down to the client

[thin stratus]

PlayerCharacter OnPossessed is also fine

[thin stratus]

Maybe, maybe not. Do you have bandwidth issues?

[azure hollow]

no I am working with API calls and since it's my first time I wanted to set some limits...if possible

[peak sentinel]

I think sending that 90kb in one time is bad

[azure hollow]

But I need to send and store data not replicating

I just have to park my data in playfab 😄 it's for a racing game

[thin stratus]

Playfab, rip your wallet

[azure hollow]

thanks hahaha

[thin stratus]

Are you doing anything else in the meantime in terms of networking?

Don't think 90kb is that bad if it's just in between everything

[peak sentinel]

Can we actually download the data like we download files from internet? Like multithreading but for bandwith 😄 That would be a cool system for sending datas like replays or anything exceeds 50-100kb

[azure hollow]

I just want to send a struct (with location and rotation) and store the data on playfab

on playfab they say the limit is 300kb per single player data, but of course I want to minimize as much as possible

[quasi tide]

@thin stratus Alright - I just did a quick test, seems like those solutions didn't work for me (both trying to spawn the weapon in the Possessed event and replicating the inventory). May have done something a little wrong though, because I was rushing. I just had to try it out because it felt like it could be a quick thing. Had to get back to work though, lol

[vague fractal]

Is there a runtime way to set a value to PktLag or is the only way the DefaultEngine.ini file + restarting the editor ?

[frosty mist]

console command NetEmulation.PktLag maybe? For whatever reason I believe it was called differently

[vague fractal]

Yeah, that seems to work, thanks 😄

[frosty mist]

Great! I think they've changed the names at some point. In this post it was just net pktlag https://www.unrealengine.com/en-US/blog/finding-network-based-exploits

[vague fractal]

I'm using 4.27 where it works

[peak sentinel]

net pktlag=value
net pktlagvariance=value
net pktloss=value
3 useful console commands

[silent valley]

You can also change it in the Play drop down button.. Advanced Settings

[quasi tide]

They were asking for runtime changing.

[frosty mist]

do those still work in later versions of the engine?

[peak sentinel]

Works for me on 4.26

Also was working on UE5EA too

[frosty mist]

Good to know. I remember that I only used those but could only find the NetEmulation commands in engine that appear to just be the same

[twin juniper]

hay, i made a very basic multiplayer game, but o can't join the game. when i try to join it just shows a black screen. can anyone tell me whats wrong?

#include "PuzzlePlatformGameInstance.h"

#include "Engine/Engine.h" //for GenEngine()
#include "Engine/World.h"

UPuzzlePlatformGameInstance::UPuzzlePlatformGameInstance(const FObjectInitializer& ObjectInitializer) {

    UE_LOG(LogTemp, Warning, TEXT("Game Instance Constrocter"));
}

void UPuzzlePlatformGameInstance::Init()
{
    UE_LOG(LogTemp, Warning, TEXT("GameInstance Init"));

}

void UPuzzlePlatformGameInstance::Host() {

    UEngine* Engine = GetEngine();
    if (!ensure(Engine != nullptr)) return;

    Engine->AddOnScreenDebugMessage(0, 2, FColor::Green, TEXT("Hosting..."));

    UWorld* World = GetWorld();
    if (!ensure(World != nullptr)) return;

    World->ServerTravel("/Game/ThirdPersonCPP/Maps/ThirdPersonExampleMap?listen");
}

void UPuzzlePlatformGameInstance::Join(const FString& Address) {

    UEngine* Engine = GetEngine();
    if (!ensure(Engine != nullptr)) return;

    Engine->AddOnScreenDebugMessage(0, 2, FColor::Green, FString::Printf(TEXT("Joining %s"), *Address));

    APlayerController* PlayerController = GetFirstLocalPlayerController();
    if (!ensure(PlayerController != nullptr)) return;

    PlayerController->ClientTravel(Address, ETravelType::TRAVEL_Absolute);
}

// Fill out your copyright notice in the Description page of Project Settings.

#pragma once

#include "CoreMinimal.h"
#include "Engine/GameInstance.h"
#include "PuzzlePlatformGameInstance.generated.h"

UCLASS()
class PUZZLEPLATFORM_API UPuzzlePlatformGameInstance : public UGameInstance
{
    GENERATED_BODY()

public:
    UPuzzlePlatformGameInstance(const FObjectInitializer& ObjectInitializer);

    virtual void Init();
    
    UFUNCTION(Exec) //Exec for allowing game-play-terminal to access this function
    void Host();
    
    UFUNCTION(Exec)
    void Join(const FString& Address);
};

[azure hollow]

can someone tell me how to serialize a struct of array into binary data??? I wanna call this function from bp later

[fading birch]

something like this:

    /* This is an example of just a placeholder struct. You can use any USTRUCT here to do this. Even pass it into the function */
    FYourStruct YourStuct = FYourStruct();
    YourStuct.Num = 5;
    YourStuct.SomeString = FString("ExampleString");

    FBufferArchive Buffer(true);
    FYourStruct ::StaticStruct()->SerializeBin(Buffer, &YourStuct );    
    TArray<uint8> Bytes = Buffer;```

[tall grove]

Hi, can someone point me to a a succesfull strategy about how to manage 4 players in differents levels?(load level instance/level streaming/ world composition)

[vague fractal]

I've followed now this tutorial to avoid network corrections and it works how it should (Holy shit is it painful to do, is it just me or is that really normal ?)
https://www.youtube.com/watch?v=Of8SGBa3WvU

Now i've read this comment here

 I know this video is pretty old at this point. Are there any plans to update this to reflect the new 4.26 changes to FCharacterNetworkMoveData and FCharacterNetworkMoveDataContainer? It seems like you no longer need to RPC parameters like requested walk speed, and can instead just attach this data to an inherited struct, but the process is still a bit confusing and I'd love to see a tutorial on it. 

And now i wonder, is there maybe an more up to date video which uses the 4.26 way ?
Also, is the 4.26 way less... painful ? 😄

[azure hollow]

I wanna make it a function so I can plug in TArray<FMyStruct> MyStruct in bp...will work for array too?

[fading birch]

It should. You would need to need to loop through it.

[azure hollow]

what should I put in the .h? I'm sorry I'm pretty noob with c++

but It's the only way I can get serialization done 😄

[fading birch]

Just make a BP callable function that would take an array of your struct. You can't really make it agnostic via BP

You should also ask in #cpp

[azure hollow]

I don't understand the code...I did it JSON but it's way too heavy

[eternal canyon]

more stuff to do

the only difference in 4.26

is u can do the exact same thiong as in 4.25

but u can also send custom data now

butttt

sending custom data would take a little bit longer to set up

[vague fractal]

That sounds like it's even more work 😅
Kinda had the hope that it's less complicated cuz this way was already like the worst thing i ever had to do in UE since i started with it ~3,5 years ago 🥲

[lusty fractal]

I'm sorry, I forgot about this channel

I have this over in #blueprint if anyone could help me https://discordapp.com/channels/187217643009212416/221798862938046464/885982287559262248

[vague fractal]

Are there some common "lag values" you should use for stress tests ?
Currently i'm testing if something breaks due to an high ping, but i also feel like testing 500 ping on the server and also on the client is a bit too hard

[sinful tree]

Is your Tile BP set to replicate?

[lusty fractal]

It is not, I will try that and get back to you

[vivid seal]

Lol i read this whole comment and was like "hey I was wondering the exact same thing!" so I clicked the video and saw that I was also the one who commented that 5 months ago...

[blazing socket]

How do I check from a PlayerState if a client is its controller?

GetRemoteRole() == ENetRole::ROLE_AutonomousProxy this doesn't seem to work

[fluid summit]

you can't replicate maps?

[peak sentinel]

You cant

[peak sentinel]

Try checking NetMode

[eternal canyon]

u can make a makeshift map using two arrays in a struct

probably would be a lot of data tho

[fluid summit]

yeah, i saw that workaround but it's too messy for what i want

yap

[tall grove]

Hi, can someone tell me whats the best strategy to manage 4 online players in a big map?
Should i load level instance each time a player goes near? should i load the entire map loaded all time?
How grounded does?

[tawdry marsh]

hi guys. i ruined my game because i dragged a couple of files around to sort out the workspace. and now the host button isnt casting the player to a server. can someone please help me figure out what i have to redirect to fix this?

[obsidian spruce]

Hi everyone. I have created a slide boost system for my charcter using apply force but it does not replicate, is it possible to make the apply force and apply impulse replicate and if so, how? thanks a lot

[vague fractal]

Oh lmao 😄
I guess you didn't found any source for it, or ? xD

[tawdry marsh]

hey guys, is there anyone who can tell me if there is something wrong in this code? i moved some files and now when host button is pressed it is no longer casting the player to a session

[tall grove]

Hi, can someone tell me whats the best strategy to manage 4 online players in a big map?
Should i load level instance each time a player goes near? should i load the entire map all time?level streaming? world composition?
How grounded does that?

[lusty fractal]

This fixed it, thank you. Idk why I didn't think of it XD

[vague fractal]

What kind of timer intervals are reasonable for the server ?
I'm not sure if an interval of 0.01 is already a no-go here
(Used to increase or decrease e.g. the stamina of a player)

[kindred widget]

@twin juniper Dude. Not the place. #lounge

[violet sentinel]

i think most of people should understand that 😄

[peak sentinel]

I care about %0.0001 😄

[blazing socket]

Ugh I'm having so much trouble.. I'm trying to set a replicated name variable in the PlayerState from GameInstance. Problem is I can't figure out how to set the variable ONLY from the proper GameInstance (i.e. the GameInstance from the client that owns the player)

Does anyone have any advice?

[mossy venture]

Don't you want to set it on the server, then have it replicated to the client?

[blazing socket]

Yes

But how does the server get info from a specific client's GameInstance?

If I use the server's GameInstance that will obviously be wrong

[dark edge]

You go thru the PlayerController. When does this happen, what's the actual mechanic you're trying to build?

[blazing socket]

Well I want players to be able to set their name in game. So in the main menu, I'm saving the name they set to a variable in their GameInstance. Once they join the multiplayer game, I want that variable to be set in the playerstate (so that all players can see their name)

Yeah I guess I could try PlayerController

So I'd need to have the PlayerController get the variable from GameInstance on the Client, then send an RPC to the server with this Name variable - which would then call SetPlayerName on the PlayerState?

It's a bit complicated so I'm trying to get it straight in my head

[vague spruce]

sup. i have a function on my AController that's tagged with UFUNCTION(Client). however, GetNetMode is always DedicatedServer and i'm unsure if the function is being called on the client or not. i'm guessing because GetNetMode is DedicatedServer then it isn't being called on the client controller.

is it possible to call a function on a client controller? right now, everything that i'm calling from the server is getting executed on the server and and never on the client, even for Client functions

[dark edge]

Yeah the player controller would send over the data, triggered by some sort of post joining method. Depending on how you're doing server joining, you can just have the name be some of the data that gets passed over on a join request

[blazing socket]

Okay thanks. Right now my joining methodology is very basic (I'm just joining via console command) but I guess I'll look into way to do that

[dark edge]

Ya that'd come with Sessions.

To reiterate, on join, PlayerController -> IsLocalController -> Get Data -> RPC to Server -> set stuff on PlayerState

[vague spruce]

i was only able to make it work by calling a Client function on the actual ACharacter, and not on the controller. i'll live with this kludgy fix for now. just wish it would have worked on the Controller . i think it's because the NetOwner of the controller lives on the server, so Client functions won't work

[vague fractal]

Is it too extreme to test gameplay features where the server has a 250 ping while the client itself has also an 250 ping ?

[upbeat heron]

I have a weird problem.
When trying multiplayer in the editor as "Player as listen server", my client ALSO has a gamemode that is firing multicast events causing things to behave wrong.

[dark edge]

Can you confirm that the client is connected to the listen server and both of them have a local GameMode?

Client window will have a game mode unless it's connected.

[upbeat heron]

I was under the impression it automatically connects in editor?

Let me look

[dark edge]

By default it does but there's a setting to make it not. That's the only way I can think of that you would have two game modes existing

I'm certain you don't have 2 gamemodes if they're connected.

[upbeat heron]

I can confirm that network messages do get sent, and post login is being called(only on the server, as you would expect)

[dark edge]

Yes but do you know that the client is connected? If both instances are effectively in single ayer they'll both have a GameMode.

[upbeat heron]

I'm not sure how to confirm that concretely

[dark edge]

So what makes you think there's two game modes then. And you don't just have a bug causing something to fire twice?

[upbeat heron]

I put a print statement inside a gamemode function, which gets called by the client

bp debug filter also seems to have two instances

I suspect the issue might have to do with the fact that im using steam subsystem but i don't know for sure

The other thing I just did, it made the logic match up was set certain fields in my game-mode to replicated

so now both game-modes did the same thing and it "looks" correct

but that is still a problem waiting to happen again

[severe widget]

this is quite weird. how are you transitioning into the level?

[meager wing]

I'm having an issue with Steam Overlay not opening, subsystem is running correctly, everything else about steam is working

but shift+tab won't open the overlay

Googling is unhelpful, most people are just having issues setting steam up in general lol

Not sure when it stopped working, but everything else works, hosting, inviting people, ect

[sinful tree]

Are you trying to open it within the editor?

[meager wing]

Nope, running by right clicking on the project and selecting launch

a built version of the game has the same issue

[bitter oriole]

Did you put an appid.txt file next to the binary

[meager wing]

is that still necessary? I have the AppID set in DefaultEngine.ini

[bitter oriole]

Yes, it is, if you're not starting the game from Steam

[tawdry marsh]

but why does it effect it ? i ment the files like in the content folder not from the source path.

[hasty sluice]

hi guys, i'm actually working on a project with a friend and we start to learn how work the online system on unreal. I was wondering if someone can give me some tips / explain me how we could play to our game online (actually working in LAN). Do we have to buy a little server? Can we make without it? Thanks for your time and sorry for the possible english mistakes

[meager wing]

I created the appid.txt with the correct app ID both in the project binaries and a built version of the project just for good measure, still no luck. It's worth mentioning that the overlay was working previously, I don't recall changing anything that should have influenced it

[meager wing]

You're wanting to do just LAN or actual online?

[hasty sluice]

@meager wing game is actually working LAN, we want to know what are the differents step to access to the online mode

[meager wing]

If you already have everything working in LAN, you should just need port-forward the device running the server

and let clients choose a server via entering an IP

if you're trying to use a serverlist, it gets a little more complicated

other than that, your options are using "Subsystems". Such as the steam subsystem

which can handle invites and such for you

[hasty sluice]

mm i see

do you have a youtube tutorial to advise me?

[meager wing]

Which option are you thinking of? The design of your project has to be pretty different depending if you're using a subsystem or not

well, just the lobby system

replication and stuff stays the same

[hasty sluice]

we have a lobby system, we gonna try the port forwarf the device, thanks for your help

[meager wing]

No problem, ill see if i can find something about not using subsystem

Are you using a serverlist feature?

[hasty sluice]

the only thing i m afraid off is the fact that the client in LAN is lagging (because we use our own machine to host the game) do we need to buy a little server to prevent this kind of problem?

[meager wing]

Shouldn't have too unless your machine is a bit under powered. Are you making a dedicated server?

[hasty sluice]

y that what i was thinking, out game is online a card game, and my pc have pretty good component so i think we can handle it right?

our game is only **

mm i not sure for the dedicated server, gonna ask my m8

[small tiger]

Yes we are using a dedicated server

[meager wing]

It's hard to say why it would be lagging, it may be because the dedicated server and client are running on the same machine. Are you sure it's network based lag and not something else?

[small tiger]

happens only when we launch it as standalone

[hasty sluice]

if u say that we can handle the game on our pc we gonna focus on the optimisation i think

[small tiger]

in the editor it's fluid

[thin stratus]

Do you intend to host the servers for your players?

Because then you'll have to rent a server. Your home PC won't cut it. Specially if you intend this project to scale.

Ignoring your lag issue

[hasty sluice]

no haha just personnal project for fun

[thin stratus]

Why even bothering with dedicated servers then

[small tiger]

would be enough to host games on our home pc i guess

[thin stratus]

Just host as a ListenServer?

[rich ridge]

Is it good to derive the animation logic with the Montages, asking with respect to network bandwidth.

[meager wing]

A listen server may be more appropriate

[small tiger]

it could works online ?

[thin stratus]

Why wouldn't it

[hasty sluice]

oh ok

[thin stratus]

The only diff is that the client itself is also the server

[small tiger]

i don't know we are newbies

on online features

[meager wing]

that's alright

[thin stratus]

Yeah then don't bother with dedicated servers if you don't need them

[small tiger]

oh okay so i guess we are already using a listen server

we are creating session

with listen param

[rich ridge]

OnRepPlayerstate is not called on listen servers too. That's also one difference

[meager wing]

Okay that makes way more sense lol

[thin stratus]

That's a server thing. Nothing to do with listen vs dedicated

Yeah then you are using listen servers already

Get the terms right . Confusing as f otherwise

[small tiger]

yeah sorry for the mistake

[rich ridge]

The listen server is also a player, if you put any logic inside rep player states then it won't execute for Lister server player

[thin stratus]

Still not a listen server specific issue

[meager wing]

They're new, and we figured out the situation eventually

[thin stratus]

OnReps in cpp don't call for servers

Doesn't matter which one

[thin stratus]

Right then what's the issue?

[hasty sluice]

sry for the miscomprehension

[small tiger]

So, we have a listen server which working good in LAN and we are trying to make it works online

but we have no really ideas how we can do it

[thin stratus]

Online you only have two options

[meager wing]

referring to the criticism of their vocabulary, still hoping to help them out

[thin stratus]

Either you use the null subsystem and connect via ip

Which requires ports to be opened

Or you utilize an #online-subsystems that offers sessions

E.g. steam or eos

Sessions are bundles of information that are stored on the master server of the subsystem and you can register sessions and query them

[rich ridge]

That's exactly what I m saying..
Your listen server is also a player, so any logic written in on rep won't execute for that player

Eg, GAS asc is initialised in on rep player state mostly , and thus for listen server player GAS asc doesn't init ..

[thin stratus]

I'm not gonna argue further. It's a stupid argument to have

[small tiger]

So, if we port forward it will use our home pc to host that's right ?

[meager wing]

Yes, it'll be hosted by the player that started the lobby

[small tiger]

Okay thanks

[hasty sluice]

thank m8 for ur tiime

[small tiger]

gonna watch that i guess

[meager wing]

If you navigate to your project directory and right-click on the .uproject file then select "Launch Game" it'll run a standalone version that I personally find more consistent when testing multiplayer features btw.

[small tiger]

yeah that's what im doing

[meager wing]

nice

[thin stratus]

One should make sure to test via standalone and if possible packaged every now and then

Specially when the project is quite far

[fluid summit]

Hi! i'm having troubles replicating one of my actors like the others.
This one Replicates as expect (Shows on client Owner Yes, Shows on Server Yes, Show on Other clients No)

This other one doesn't show on owning the client, but yes on the server (if i want it to show also on the owner, i need to check Always relevant, but i don't want the other clients to know about it)

i want to replicate from server to owner only, does anyone know what may be wrong? The inside components are set to replicate

[dark edge]

So does anyone here know WHY they made the onrep behavior different between BP and c++?

[fluid summit]

Because they didn't wanted to replicate the previous errors.

[fluid summit]

I think i solved this, but i'm not sure.

Spawn actor only spawns on the client side if it's a rpc (with actor replication set to only relevant to owner)
Building spawns okey on client with execute on server (also with actor replication set to nly relevant to owner)

not sure why, but it fixes the problem.

[dark edge]

Why are you replicating the spawning of the actor instead of just replicating the actor itself?

[fluid summit]

I want the actor to show only on the owning client and the server.
I can't make it to replicate on the owner without a rpc, not sure why

[fluid summit]

This are the settings i'm using for the actor

with my other actor and the same setting, works okey.

[dark edge]

Wait why is the server running input? Is this a listen server or dedicated server setup?

[fluid summit]

dedicated server, sorry i forgot to mention.

[dark edge]

So the 2 -> multicast SpawnActor will never run. Honestly this looks spaghetti and real bad. Start over, you want to spawn an actor that only server and owning client see right?

[fluid summit]

yes, only owner and server should see it

2 doesn't spawn anything there
3 does spawn the building actor

both actors, same settings

[dark edge]

That all looks screwed, should just be
Client Input -> Run on Server -> Server spawns actor, sets owner to player/PlayerController, sets replication condition to OwnerOnly

[fluid summit]

oh, those 2 pictures are from the player controller

the actor giving troubles has as a parent the "top down character", maybe that's relevant.

[fluid summit]

so the rpc wasn't actually solving the problem

[fluid summit]

Okey the problem was on the parent of the class, not sure what, but i removed it and it works ok now.

[buoyant sierra]

Hi all! New here, and to the engine.
Left Unity when I wanted to start dabble with multiplayer... aaaand I guess y’all know the state of that in Unity.
So I was pleasantly surprised by how great the built in systems in Unreal are!

Or well, I was, until I tried to make a top down-template multiplayer (man what a rabbit hole).

So I’ve done the (what seems like, as no updated solutions are found via google since ‘14) “pc with proxypawn that on server spawns the player with an aicontroller and proxypawn copies the transform”-yata yata.
Not really great if one introduces lag.. as there is no prediction.

Soo. Have anyone tried/successfully implemented a system where you like grab the points from UPathfollowingComponent::GetPath and like do AddMovementInput to have the built in prediction love?

[upbeat heron]

Sorry for late response but I directly launching the game map with multiplayer as listen server active

[tall grove]

Hi, can someone tell me whats the best strategy to manage 4 online players in a big map?
Should i load level instance each time a player goes near? should i load the entire map all time?level streaming? world composition?
How grounded does that?

[keen condor]

Hello , may i ask someone in private few questions about multiplayer c++ games ?

[hoary lark]

Probably not but you can ask everybody in public

[keen condor]

If you say so : This is my understandings of unreal mp so far. (I'm using only c++)

i have clients and a server , if i wan't to replicate my movements on other clients i just need to replicate my movementDirection vector on others clients and then the other clients will localy actualise the movementDirection vector of my client Character's copy.
So let's imagine that i just wan't to send inputs to a server and it will actualize my position and positions of my character's copies, this how i would make it : i'm using player controller, i create a class that manages input (let's call it InputManager) , and define a replicable myInputManager variable from InputManager class inside the PlayerController class. So when myInputManager is replicated , copies of my PlayerController on other clients will have their ("myInputManager") updated. Finaly i just have to localy set whatever i implemented depending on the final input data coming from the server.

so if i'm not totaly wrong , i'll ask few questions : is it a good idea to replicate a player controller for all character's copies , is it better to implent this stuff directly on the character class ?
If i wan't to create a class that manage all network stuff, should i make it as a component of my character's class ?

[hoary lark]

would you like to make all this to learn? are you aware all of this type of functionality already exists in character movement component (for "humanoid" style movement) ?

[keen condor]

yes i'm learning right now , i'm trying to understand all basic concepts so i can go into more serious projects

this is my 2nd day on unreal

I just wan't to be sure that i understood multiplayer concept correctly

[vivid seal]

for what its worth, if you're just starting unreal I would try to implement your game in single player first, then remake in multiplayer. mp concepts will add like 4x as many issues you have to solve, and there will be a lot of things that you won't be sure whether the issue is the actual game code or replication

but if you're set on multiplayer, yeah check out the Character Movement Component

[keen condor]

thanks for your answer , single player is not scaring me at all as it's pretty much the same on every engines , all i have to do is checking the doc and generally i find what i wan't on it, but i never went deeply into multiplayers concepts so i read lot of things and i just wanted to be sure that i understood decently basic concepts

[fluid summit]

Hi, one question.
If you spawn an actor on owning client, how secure is it to use that actor's information for later (database save on dedicated server)

Because im forcing my self to réplicate actors on the server that I only want on the client, but that i need secure information from them

[hoary lark]

TBH, at 2 days in, it doesn't matter how awesome you might be in other engines, you should be doing nothing but following tutorials and gaining general familiarity with the new engine. your solution might work in a general sense, but it also wouldn't work at all in unreal because of how replication works in UE

regardless, I will say the pinned "network compendium" provides a lot of good general knowledge on networking stuff in UE, if you haven't seen it yet

but you need to learn the game framework first, from UE docs

[keen condor]

I mean , i didin't skip the learning part of unreal , when i managed to do something with the engine i'm just trying to adapt it for a multiplayer usage

i'm pretty sure it's not the most efficient way to learn , but this is the way i choosed . And thank you again for your advices and your help !

[finite goblet]

does COND_InitialOnly repeats when your actor becomes relevant again ?

[winged badger]

its spawned again when it becomes relevant, unless its static

so yes

[vague spruce]

sup. i've got some AIs on the server. i need to run an RPC that disables collision on these AIs on the client when they die. how do i let the game client know? Client is not working. i'm guessing it's because the AIs aren't actually real clients.

do i need to do some multicast shenanigans

[peak sentinel]

You need to use OnRep on pawn class

Multicast is fire and forget

[vague spruce]

yea that's what i ended up doing

thanks @peak sentinel

just figured it out

[peak sentinel]

Np (:

[vague spruce]

    UPROPERTY(Replicated, ReplicatedUsing=OnRep_IsDead)
    bool bIsDead;

    virtual void OnRep_IsDead();

this did the trick

[peak sentinel]

If you have a health variable replicated I'd do that on there

if(Health < 0)
{
disablecollision();
}

[vague spruce]

true true

i'm using GAS

i'm half asleep, just wanted to solve this problem

will properly fix it tmrw

[peak sentinel]

Alright, good luck

[wise zephyr]

Hey guys i am trying to replicate an instance static mesh...both client and server have different index's for each body of the instanced mesh how do you guys go about this? i am trying to destroy a body of an instance static mesh for both client and server

[fluid summit]

I can only think of an index of parts and replicate the values on it to both server and client, than use it as references

but probably there's a better way to do it, i'm new to multiplayer

[wise zephyr]

how do i get the indexes of each body?

[fluid summit]

If you can't get the indexes, how do you know that server and client have different indexes?

[wise zephyr]

ahhh i got an idea thanks!

[fluid summit]

I'm doing some testing and i'm still confused on how replication of a new actor/Uobject works if done on server

if i run this

and press one, the ProxyClass is only valid on Server

the setup is a dedi server with a custom PlayerController and a Default Uobject (ProxyClass) set to replicate on the custom controller.

shouldn't the ProxyClass be valid on both server and client after pressing 1?

[sinful tree]

You need to do more than just mark the "Proxy Class" reference as replicated. You need to mark the actual "Proxy Class" blueprint as replicated.

Also, I don't think UObjects will replicate by default?

There's C++ you have to do in order to do so if I'm recalling correctly.

[fluid summit]

Oh that may be the reason than

[sinful tree]

https://jambax.co.uk/replicating-uobjects/ --- there's a certificate expired warning when going to this page, so up to you if you want to proceed to it or not.

[fluid summit]

I need some way to validate/write data on the server diferently depending of a class, this affects that client and server only.
will a replicated Uobject be the way to do it or maybe there's a better way?

[sinful tree]

Why do you even need a uobject for that?

Eg. Player's can RPC data to the server.

[fluid summit]

not sure, i tried with Actors without results.

I'm trying to figurate how to get a piece of string from a database be interpretated diferently depending of the unit class (but with the units being client owner/server only)

[sinful tree]

Ok, but then that's probably something you don't want to do on the client at all.

You let the server tell the client what to do based on the database data.

The server should know the unit class.

If you want the client to change something, that's fine - you can just RPC the selection the client is making without having to use a UObject as an intermediary.

[fluid summit]

maybe i'm approaching the problem in the wrong way.
This is 2 clients running standalone on a dedi server (default third person template)

how can i get the actors to only show on the owner client, but yet, be able to trust the information they have?. (without them bumping into each others)

[sinful tree]

So you basically want on each client to only be able to see the actor they control kinda thing?

[fluid summit]

my process right now is

1. get character info data from database as string
   2)spawn a class specified on the string (unit class)
   3)feed the string to the class and let it do whatever it has to do with it.
   4)do some stuff with the unit on player owner side
   5)when server detects Log Out, use the information on that controller (the spawned class from point 2) to save the character info into the database

[fluid summit]

that plus them not being in the same space, but yet running on the server for security reasons.

i'm trying to do this basically

[sinful tree]

These characters would never interact with one another?

[fluid summit]

https://www.youtube.com/watch?v=v4klOqxePHA&t=71s 10:00

[fluid summit]

no, never.
If at some point i need to make them interact, i'll spawn a replicated puppet that is always relevant.

but i'm trying to build the "city side" first.

[sinful tree]

So even the world that the characters exist in, would theoretically be completely separate?

Ie. I have my game map, you have yours?

I can build a town in one spot, you can build a mine in the same spot?

[fluid summit]

yeah

with the information of all yours buildings / characters being saved to a database through a dedi server (best way i could find)

i'm trying to fake a mmorpg

[sinful tree]

Then yeah, you need to rethink how you're doing this. If the characters are not interacting at all, then there's no point in having them connect to a dedicated server.

Especially if they're meant to have different game worlds.

[fluid summit]

how can i trust the info they have if not?

[sinful tree]

What does it matter if it is effectively a single player game?

[fluid summit]

you can play on your separate city (things relevant only to your player)
or go and explore a persistant map where some things are shared among players

https://www.youtube.com/watch?v=v4klOqxePHA&t=71s (16:00)

like a monster or a city that's replicated for everyone (with the info of this actor being saved on the server and than to the database)

my approach so far is to have your city on the same map with owner only replicated actors and than when exploring the map, spawn a pupper that's replicated to everyone and go with it

i think a better example would be diablo 3.
If you can play on your own session, how can i trust your info when pulling it into the database?

[sinful tree]

If you look at it like that, then each player would have their own dedicated server running.

[fluid summit]

how do you think they are going on that game about getting your city for yourself and still impact the server database?

i still can't figurate out how to get that part

(not sure if this makes more sense)

1)player exclusive content that is saved into database
2)shared world content driven by database
3)data from player exclusive content needs to be trusted since it can interact with the shared world content.

I apology if it's a mess

[sinful tree]

It's not so much a mess as something that's a bit complex and I don't have 100% of the answer for you either.... Just trying to think about what I've learned along the way..

[sinful tree]

Your point #3 is what is driving this home - you do need some kind of server (not necessarily a UE4 server) that validates what the player is doing if their world can interact with the shared world as a malicious player could negatively impact the experience of other players when in the shared world. Using a UE4 server would be fine, but you either have to:

1. Run a separate dedicated server instance for each player.
2. Learn about "World" objects within UE4, and figure out how to have multiple players hosted on one dedicated server, each with their own World instance for the player-specific worlds. Unfortunately, I'm not very familiar about these objects myself, but I do know they exist and I believe they can be used in such a way.

For option 1 (Dedicated servers for each player):
As the player builds or do whatever it is they do on their world, you can validate what they are doing on the dedicated server and save the data to the database - when they join the game again, you load the world data and replicate to the client all the things they've done.

When they move into the "Shared World" you would have them travel to another dedicated server where they would be able to interact and see each other. The dedicated server again would load the values for the specific players and replicate to all clients.

For option 2 (World objects):
You again can validate whatever the player is doing on the dedicated server and save the data to the database and load it back to them, but when loading, you create their World object and populate it, and spawn this player into that World.

When moving into a shared world, you'd probably want to have separate dedicated servers specifically for this purpose that don't muck about with the whole concept of World objects - so just standard Dedicated Servers.

[fluid summit]

No problem, any advice is appreciated, i just reached into the forum to see if someone can help.

oh the previous message just popped

[elfin sail]

how can i check client joined the server ?

like when server level loaded

on client

[fluid summit]

on GameMode you can use "Event OnPostLogin" that gets triggered each time a new player controller logs in, not sure if that is what you are looking for

GameMode only runs on the server.

[sinful tree]

If you only care about the client, then use the player controller's begin play.

With a switch has authority set to remote.

[elfin sail]

gamemode is only on server

[elfin sail]

beginplay of what ?

there is code related to server

i think gameState is bes option to check

client or server

[sinful tree]

If your concern is on the server, then Game Mode OnPostLogin is probably the better place.

[fluid summit]

I think the setup can work if i use the "your world" like an inventory.
Storing all the data on replicated actors with no transform and spawning some non replicated actors to represent those first actors.

So you can have one part of the map where all the players are playing on, but only seeing their content.
And in other parts of the map, spawn replicated actors with transforms.
Would this be a murdering of the server? having a lot of replicated actors with no transform on the same part of the map.

[sinful tree]

How would the server know where to allow one player to move vs. where to not allow another?

Eg. Let's say I build a house somewhere. My character should collide with it, other characters shouldn't, but enemy units that exist within "my world" should.

[elfin sail]

any idea why this variable is out of scope

i cant access in next level

[fluid summit]

On your World, there is no interaction with other players at all, only on the shared World.

[sinful tree]

But how you want to program it, you will have other players in the server world.

Eg. You and I both connect to the same server, we just don't see the same things.

[fluid summit]

Right, we dont see the same things, only if we look/mové to the área of the map where some actors are réplicated to all

[sinful tree]

So again, the problem is, how does the server know where I can walk freely, but you cannot.

[fluid summit]

Well, those instances would be only to show and drive the behavior of the real actors.
Kind of like having a HUD of actors

Movement on your own World is irrelevante, the gameplay there is data drive mainly

Like resources management, trigger building upgrades, etc

[sinful tree]

SO no custom placement of buildings?

[fluid summit]

Oh I see the problem

My real buildings would collider with your building, so I cant have custom placement driven by colision check

🤔

That may be solved with a placement matrix

2d array to check which spots are taken, so when trying to place a building on a custom location, I check on the matrix if any of the points requiered are taken, meaning, another building is on that spot already

That may actually work, im still worried about having all the actors with no transform replicating on owner.

[sinful tree]

Still, what about where your player is allowed to move around or any AI that you may want interacting with the world?

[fluid summit]

Maybe there I can spawn a proxy puppet that is always réplicated to everyone (the combat system is not real time, forgot to mention that)

Its a turn based automátic simultion, so that there's no live replication requiered

The job of the dedi server on those cases would be to spawn the monsters which everyone can see.
Than on battle request, take the character data and the monster data and run the simulation (on server) and apply the results to the involved data

There is still the problem of how spawn monsters that only the player can see and be trusted

Example of how the battle simulation goes.
https://youtu.be/87oKgBq7DaM

[buoyant sierra]

Does anyone have a good click-to-move solution with client prediction for multiplayer?

[slow wing]

Does anyone else have problems where simulated proxies using CMC do not smoothly come to rest? When another player stops running, my client always overpredicts their location and then has to snap them back a bit to where they actually stopped. I think you normally resolved this by buffering some movement rather than playing it all in real time, but does UE4 have some way to smooth this out easily by default, or is this even something else others have experienced (maybe I am doing something wrong)?

[lucid pewter]

How can I make a system where you enter with IPv4?

[fluid summit]

with a dedicated server for sure you can connect using IPv4, you need to be sure that you have the ports open on your modem on the server side and check that your internet provider does not have another IPv4 direcctions on top of yours.

[lucid pewter]

So all those YouTube tutorials where they come in with the IP address are fake? Do you still need a dedicated server?

[lucid pewter]

I wanted to do something Chill so that maybe they can merge with Hamachi

[fluid summit]

i think you can also join using listen server, but i haven't tried myself. i'm only learning dedi at the moment

with hamachi you can for sure

[lucid pewter]

and which node should i use? I followed some tutorials but they didn't work

[fluid summit]

you can open the console and type "open yourlocalipaddress:port" to join a game on your network that is open to connections (listen or dedi)

[lucid pewter]

Only through the console?

[fluid summit]

same on bp, check "open level" node (instead of map name, you can use local ip)

[fluid summit]

yeah, that should work if your ports are open

[lucid pewter]

Now I tried to myself ... but he didn't let me in

[fluid summit]

Check this tutorial on net modes

https://www.youtube.com/watch?v=JOJP0CvpB8w

[fluid summit]

that should give you 1 client playing as a server and one client connected to that server by default

[lucid pewter]

Yes, I try so if it works .. am I wrong? There is no GameMode in the main menu, is that a problem?

[finite goblet]

What happens when a pointer to a replicated actor is replicated which itself hasn't replicated to the client yet?

does it call OnRep again or just silently fills out the pointer as soon as the actor spawns on the client?

[tawdry marsh]

can someone helping me on my host session multiplayer nodes? i moved something and now it needs something updated for it to read the host session

[tawdry marsh]

anyone please?

[fading birch]

your reference to your game instance isn't valid. Check you're setting it properly

[tawdry marsh]

it was fine before i moved the files

so now how can i reatarget it to understand it was fine

what do i hav eto remove and relink

[tawdry marsh]

.

[fading birch]

this is a question for #blueprint tbh

[tawdry marsh]

kk thanks.

[uncut atlas]

Hi, are behavior tree tasks automatically replicated? Ex. If I call a task to play an animation, will it play for everyone (host and clients)?

[meager wing]

Anyone have an opinion on the SmoothSync plugin from the marketplace? I'm wanting to use physics mechanics in my game

some people say it works for physics, some say it doesn't work that well at all

[vagrant lance]

Hi, I’m trying to get public matchmaking working with advanced sessions. It works fine in editor but fails to connect in a cooked build on steam. It works fine through normal invites though. Any thoughts what could cause this?

[vagrant lance]

In my experience yes

But I think animations are best done through an animation blueprint

[uncut atlas]

I'm referring to playing animation montages

[vagrant lance]

I have trees sending blueprint interface messages to the controlled character which trigger the montages from there, that works for me

[uncut atlas]

Ok thanks!

[peak sentinel]

They are not replicated, everything is server-side

[fluid summit]

Hi! i have a few questions about this documentation, maybe someone is more knowledgeable on the topic.
https://docs.unrealengine.com/4.26/en-US/InteractiveExperiences/Networking/Actors/ReplicationFlow/
what is the criteria for NetDormancy? on the document says only about initial state. How does it behave after that? can i one actor dormant again in order to save network bandwith? can i change the time it takes for one actor to become dormant?

AActor::IsRelevancyOwnerFor - Called to determine relevancy when bOnlyRelevantToOwner is true

AActor::IsNetRelevantFor - Called to determine relevancy when bOnlyRelevantToOwner is false

In what scenarios would this 2 be significant? i think that with "bOnlyRelevantToOwner " it would be enough and this 2 become useless.

[winged badger]

@fluid summit easiest way is to just read AActor::IsNetRelevanFor default implementation of the function

but it tends to go through cheaper checks first - is always relevant, you don't need to know anything else

is relevant to owner only - check if RealViewer (PC in this case) is the owner, and thats it

if its not relevant to owner only, then it goes into the default distance based relevancy, if its within 15000 UU from the last position client sent in ServerUpdateCamera

its relevant

[vague spruce]

is there an easy way to tell through debugging whether an actor is local or server-side?

[winged badger]

Role and RemoteRole

add them to watch

[vague spruce]

fantastic

thank you!

doing that now

[winged badger]

they are both in AActor scope

note that an actor spawned by the client

will have Role Authority

on the client