multiplayer

[split swift]

no

the problem is that it properly deletes the weapons from the client when the server first picks it up but after that if he tries to pick up a weapon that was placed by a player, it only deletes from the server and not the clients

[thin stratus]

That can have many reasons though. In theory, calling Destroy on a Replicated Actor on the Server is enough.

Who is "dropping" the weapon? How is that done? Cause you need to spawn the Weapon on the Server if you drop it.

And only on the Server for that matter.

[split swift]

the drop logic is done through a multicast that is done through the server

[thin stratus]

A Multicast?

[split swift]

yes

[thin stratus]

Are you doing "Multicast" -> "SpawnActor"?

[split swift]

yes

[thin stratus]

That's wrong

[split swift]

whats right?

[thin stratus]

Only call Spawn on the Server

[split swift]

k

[thin stratus]

Spawning of Replicated Actors is also replicated to Clients

I really hope you aren't following some tutorial that teaches you that crap

Cause if so, drop that and the maker of it :<

[split swift]

should i do all the equip and pickup logic in the server or make the multicast call a server RPC specifically for the spawn actor?

[thin stratus]

Multicast into Server RPC doesn't make sense, cause the Multicast already comes from the Server

All of this should happen on the Server

There is no need for any Multicast here

Multicasts in general are not for State changes

Cause those can be missed if out of relevancy or late joining

The Drop should mainly be a ServerRPC when the Player presses the key

Same as the Interact

And after that you stay on the Server

you perform the Spawning, change the variables that you use for your equipment and that's it

Any state that must be communicate with the owner or other clients would run through replicatd variables

That also goes for your equipment code btw. Not only for Spawn and Destroy aka pickup and drop.

[split swift]

if the server enters the BPI and out of that is calls an event back to the player class, is that still on server or would that be on client

[thin stratus]

You stay on the Server

After the Server RPC, given you called it in a Client-owned Actor (such as the Character) you are on the Server

You only get back to Clients via ClientRPC, Multicast, or OnRep Variable

So for your example, the E Key is called on the local Client (let's ignore ListenServers for a second). The ServerRPC after that goes to the Server version of the Client's Character.
All the Code run there, runs on the Server instance now. That includes the getting of the overlapping items, and the BPI call.
And the target of the BPI call also still remains on the Server.

Which is what you want, cause now you can modify the Players Equipmnent with the Weapon and call destroy on the Actor.

And all of it (let's assume your Equipment code is not a mess) would "just work"

[split swift]

if a variable is set to replicated and it changes on the server, will it automatically change for the client

[thin stratus]

--
In theory, a ServerRPC is mostly only needed if the Client needs to tell the Server about something that the Server doesn't know about.
The best example for that is the Key Press. You want the event of the key press to be known by the Server.
However, the Server knows all about the Inventory and the Weapons on the floor etc. so after the E key ServerRPC, there is no need for any other RPC.

[thin stratus]

Yes, that's the idea of Replicating a Variable. That only works in one direction though.

A Client changing the variable locally has no "global" effect

It will only change locally for them

Btw, have you actually read the Compendium for Multiplayer yet?

Just making sure it didn't pass by

[split swift]

yes

[thin stratus]

Alright, the Variable question would theoretically be answered by that already

I may also add it becomes a lot easier to handle the whole replication stuff if you ensure most of your authoritive code stays on the Server

There is also the topic of prediction, but with you current struggles, I would ignore that for now

What I mean with that is that it might be easier to, after the initial RPC; ignore any Client problems for a second and simply code whatever you have to do (changing the Inventory, Spawning/Destroying Actors). And then afterwards you can have a quick thought about what of this stuff still has to replicate to the Clients, which is usually State Change.
And State is done via Variables (e.g. currently equipped weapon).

If you need a function to call when something replicated, you'd use the OnRep/RepNotify stuff.

[split swift]

thank you for taking the time to explain to me in detail how networking works. its all working now.

[lucid badger]

With latency emulation on Average/ServerOnly using a regular CMC with default settings and nothing special, just a fixed movespeed. When the server watches the client move, movement is smooth as butter. When the client watches the server pawn move, there seems to be prediction/correction where when the pawn stops moving, it jumps back slightly.

actually this has nothing to do with latency

I turn it off, same issue

Client sees a hitch in server pawn movement but not the other way around

Guess I just didn't notice it before

This is true for client->client as well, when there's extra clients they see the same correction

Even with 0 latency

[thin stratus]

Latency shouldn't matter. Package Loss would though

[lucid badger]

Nah it's all 0

Server emulation entirely off

Visible correction on client when another pawn stops moving

[thin stratus]

That's normal

Sim Proxies are extrapolated iirc

[lucid badger]

Oh. Um. How to mitigate it then? It's extremely noticeable even with 0 latency The bright side is that increasing latency doesn't seem to make it worse, somehow

[thin stratus]

Check if you can find anything in the settings of the CMC

[lucid badger]

I poked around with smoothing settings to no avail

Switching to linear or even disabled changed not at all

[thin stratus]

The SimProxy basically continues based on its last info. Which would get corrected backwards when suddenly stopping

[lucid badger]

Maybe it's less noticeable with a properly animated character, and is only so obvious rn because the characters are just capsules 😛

[thin stratus]

Might be. It shouldn't be so bad that you get annoyed by it. Every game usually has that to some degree

[lucid badger]

I guess since it took me this long to notice it all I'm just fixating

Curious that it doesn't seem to get worse with more latency

[viscid tapir]

UActorComponent::OnRegister is also called client-side ?

[languid bridge]

Is there a way to get what map a server is running before connecting to it? BlueprintSessionResult only appears to return Ping, Server Name, Current Number of Players and Max Players.

[queen escarp]

https://gyazo.com/7457531027cf1ed7a87b6826f0c4d4dc

do anyone know why the server / clients treets the replication of the fracture diffrerently ?

[lucid badger]

Physics is not deterministic

[queen escarp]

left server rigtht client

[lucid badger]

This is how it's always been in like every game I've ever played

[queen escarp]

yeah but thers 0 debree at all on server

[lucid badger]

Oh is that every time? I thought that time it just sort of fell into one spot

[queen escarp]

no every time

[lucid badger]

Looks like they are getting stuck somehow

On each other

see how the back is sorta spazzing out

[queen escarp]

has enything with these ?

[lucid badger]

I don't think this has anything to do with replication once it breaks into separate parts it doesn't seem like it's replicating anymore

[queen escarp]

yeah...

[lucid badger]

I don't think you would want the pieces to replicate anyways

If the server destroys the chair, is the situation reversed?

[queen escarp]

no

or yes

[lucid badger]

weird that it's right for the client and wrong for the server

[queen escarp]

its reversed

[lucid badger]

Oh ok

So whoever breaks the chair sees it right, but the other side does not

[queen escarp]

yeah

[lucid badger]

Ok so it's something with how you are communicating to the other players that you broke it

[queen escarp]

or acctually no

my mistake

always broken on server only

even if server kills it

[lucid badger]

That's weird as hell

[queen escarp]

yeah and if i play as standalone then it works for the server/client

uhm.,..

https://blueprintue.com/blueprint/9cbs789u/

maybe its because im RPC´´ing replicated components

?

[loud pike]

Hello, how can I troubleshoot, steam fatal error ? Basically when I start a specific ability only in multiplayer and on steam the game has a fatal error crash ? And I would like to have the logs to find out what it's about since I have no error number with it

[pliant haven]

Is doing player input in playercontroller best practice for multiplayer?

[lucid badger]

Is my understanding correct that the only reason to not use Client Auth on CharacterMovementComponent is that it enables the client to cheat? Such that if cheating isn't relevant to your game, there's no reason to bother with (for CMC) Server Auth and Prediction and custom saved moves and all that? Or are there other elements I'm missing

[stoic lake]

Hi, is there a way for me to implement passwords into sessions without using advanced sessions or another plugin?

[lucid badger]

There's always a way 😛

[stoic lake]

working on an asset pack so need to keep everything stock

[lucid badger]

If the plugin can do it surely you can too, right?

[stoic lake]

https://tenor.com/39fu.gif

[stoic lake]

the plugin did it with C++, which i am definitely not familiar with haha

[lucid badger]

Sadly no that's way above my paygrade

[stoic lake]

was wondering if its doable in bp

[lucid badger]

Hmm

[stoic lake]

the only way i can think of doing passwords is by storing extra information in the session, but the only way to do that is by using one of those plugins

[lucid badger]

My completely asspull guess is that you're probably going to want C++ for something like that seems like we always do

[stoic lake]

seems like it right

[fossil spoke]

It highly depends on your game as well.

If there is, for whatever reason, a desync in geometry on the Server vs the Client. Your Client CMC may end up in an inappropriate state.

This can affect how other Clients see that Character.

[rocky kestrel]

Have anyone used Easy Anti-Cheat in own game? People say it is free but can I use it on my Steam game?

[fossil spoke]

So there are still advantages to Server Auth of the CMC.

Even if you dont care about cheating

[fossil spoke]

Ask Easy Anti Cheat?

What restrictions there are to using their product.

[stoic lake]

I just found out about beacons. Is there someone who could help me understand how to use these in blueprint?

[fossil spoke]

Beacons, from memory, are not usable in Blueprint without setup from C++.

Beacons are an advanced feature.

Beacons are a good way to deal with Passwords though. So you are on the right track.

[stoic lake]

I was actually able to make a beacon actor if that's what you mean

[fossil spoke]

They may have better exposed them in 5.x

But just because you can make a Blueprint from them, doesnt mean they will operate out of the box in Blueprint

[stoic lake]

right that makes sense

do you reckon it is possible at all to create a password system without the use of C++?

[fossil spoke]

There are alternative methods.

They are inelegant however

And you have to accept some inconveniences

[stoic lake]

id be happy to learn them

[fossil spoke]

Actually, thinking about it now, there might not be.

I dont think you can refuse connections in Blueprint alone.

[stoic lake]

In my case, reading data from the session on the client is good enough

So the client receives the password and does a local check

[fossil spoke]

Well you can just hash the password and put that into the Session information.

The Client would then input a plain text password, which you also hash.

Then compare the hashes

[stoic lake]

That was my initial idea, however I'm not sure how to add additional session info using the base OSS

since this is really all you get

[fossil spoke]

Via BP, im unsure about that as well

BP is not really designed to handle advanced uses of the Online system

Out of the box.

Thats why plugins exist

To expose that stuff.

@stoic lake Have you looked at the Redpoint EOS Plugins?

They are very well written.

[stoic lake]

I definitely have, and do have some passwords systems setup for other games, however this is for my own marketplace asset. So I'd rather not use other plugins

Would keep people from looking into it i think

if there are any resources I can look into that would help me get extra session info set up in C++ that you know of, that would work as well

Would be very handy to know regardless

[languid bridge]

Tangential to my previous question: How the hell do I find a Dedicated Server session? 'Start Session' only works with Listen Servers and 'Find Sessions' only finds started sessions.

[lucid badger]

Sure that makes sense and had occurred to me. So is that the only other consideration really?

[fossil spoke]

Well, anything that causes the Server to disagree with the Client will be an issue in general.

If you are happy to accept that, then not really anything else to it.

[stoic lake]

Would it be possible to save a blueprint session result in a savegame and reference it later when someone restarts the game to rejoin that session?

[fossil spoke]

Only if that Sessions information remains identical.

Sessions are transient. In that, a Session created by the same user multiple times, will have different Session information.

You cant really "save" Sessions to reconnect to later.

Unless they are still available with that same info.

So it really depends on the time factor here.

If you are talking about reconnecting immedately after say, a crash. Then sure, the Session is likely still around.

[stoic lake]

That's exactly my intention

great to know that that's a possibility

[fossil spoke]

But if I log off for the night and come back tomorrow, whatever/whoever was hosting the Session might have closed it.

So it wouldnt be available anymore at that same Session information.

[stoic lake]

Perfect, thank you!

[fossil spoke]

You may also be interested to know that the Server keeps a list of "old" PlayerStates

So that, if you reconnect, you can regain your state of play prior to leaving.

However I dont think these are available in Blueprint.

The Server will hold onto "old" PlayerStates until the next level transition I believe.

[lucid badger]

Yeah makes sense. The issue that occurred to me was something like a sealing door getting desynced. if it's closed on server but not client, then with server auth, player would get corrections and be unable to pass thru the door. But client auth he can walk right through.

At least for my case all the examples I can think of are contingent on something else bugging out first

[fossil spoke]

Yeah precisely.

[lucid badger]

Ummm

These... won't stay checked ...

Other settings work fine

But these are off every time editor starts again

[lucid badger]

This didn't work in either DefaultEngine or DefaultEditor

But this did soooo

[hazy stone]

When an actor was replicated to the client, does Unreal guarantee the actor's owner and other replicated variables are replicated before BeginPlay? For example,

// server
AMyActor* MyActor = GetWorld()->SpawnActorDeferred<AMyActor>(..., TheOwner);
MyActor->SomeReplicatedVariable = NewValue;
UGameplayStatics::FinishSpawningActor(MyActor, ...);

Let's say TheOwner is also a replicated actor like a pawn, when the client's BeginPlay happens, can I use it's owner and the replicated variables?

[fossil spoke]

@hazy stone Correct.

Assuming that the Owner is a valid Actor on the Client.

[lucid badger]

That hinges on spawn actor deferred right? Because I've not tried that but when I was regular spawning and then setting replicating values, the replicating values weren't there yet on BeginPlay

[fossil spoke]

@lucid badger Yes

[hazy stone]

So if the owner and the actor were spawned on the server in the same frame, the owner might be lost in the client side?

[fossil spoke]

It is all dependant on when the Actor Channel is opened for that Client, as it will snapshot its values at that point and they become part of the initial bunch.

[fossil spoke]

There is no guarantee of replication order, so in that case it is not.

The Client is likely to not have the Owner resolved by the time the other Actor is also replicated.

There is also no guaruntee those 2 Actors channels will be opened in the same bunch at the same time on the Client.

Network replication is by its nature, asynchronous and you should always assume that and plan accordingly.

[hazy stone]

got it, really appreciate it!

[wraith venture]

ok I'm very new to multiplayer

I'm trying to create a widget and display it

I just grabbed event beguin play, created the widget, and then added to viewport and I attached 'get player controller' as the owner

but it looks like it creates the widget on the server automatically and then gives me an error

I thought i had to send it to the server manually for that to happen

am I lost? how would I create the widget only for the local player?

Blueprint Runtime Error: "Accessed None trying to read property CallFunc_Create_ReturnValue". Node: Add to Viewport Graph: EventGraph Function: Execute Ubergraph BP Plaguehead Blueprint: BP_Plaguehead

this is what I keep getting

ok I refactored it according to a basic tutorial, the way I assumed i'd have to go

on even beguin play I just call add HUD to server but it always gives back that accessed non error

wait i think i found it

just added an isserver node check with a branch and the error is gone

is there more to it than that?

[fossil spoke]

You should probably make use of the HUD class to create and manage Widgets. This will save you from having to use RPCs, which is entirely unnecessary.

[wraith venture]

can you expand on that or send some links?

like are you telling me I should use cpp?

oh wow ok I've never actually seen the HUD class used before

guess I'll look into this

so the HUD class is a blueprint, am I supposed to build my widgets and call it fromt he HUD class and then call that from the player?

[fossil spoke]

Generally speaking the HUD class is used as a central point to generate and manage overarching Widgets.

It is an ideal place to create a "HUD".

So basically it would just be what spawns/instanciates your HUD Wigdet.

[wraith venture]

ok

[fossil spoke]

Instead of whatever current setup you have with those RPCs

The HUD Class is created when the PlayerController is.

[wraith venture]

does every player controller have a HUD class automatically?

[fossil spoke]

Yes

[wraith venture]

it's not the same thing as this blueprint class I'm seeing under blueprints?

[fossil spoke]

The naming convention is confusing.

It is a Blueprintable class.

AHUD

It is not a Widget

[wraith venture]

ok so it calls the widget that I made my hud in?

[fossil spoke]

You can change the default HUD class on the GameMode.

[wraith venture]

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

this thing?

[fossil spoke]

It doesnt do that for you, you manage that within the HUD Blueprint you override.

[wraith venture]

looks like I need to do a deep dive in this

[fossil spoke]

Im going to guess so, as I havent watched that video.

[wraith venture]

ok thanks for setting me in the right dirrection

[fossil spoke]

That is a direction, might not be the right one. That all depends on your needs 😛

But sure thing.

Good luck.

[wraith venture]

it sounds like it's a good dirrection

[fossil spoke]

👍

[wraith venture]

i mean mathew Wadstein says it's legacy

so i gotta see if it has benefits

he says it's not not interactable is that true?

[fossil spoke]

It is a legacy class, it used to be what you made UI in prior to UMG.

It is still useful as a manager for Widgets though.

[rain condor]

Io, i have an inventory system with array. When i drop an item i remove it from array but still takes up space

[fossil spoke]

You are best to ask these questions in #umg as we are drifting far offtopic here

[fossil spoke]

You are just emptying the element, you arent removing it.

Call the Remove function on the element index instead.

[rain condor]

But I have a spatial inventory where each tile is part of the array

I leave it empty so I can use it again

[fossil spoke]

THis is probably better discussed in #blueprint as I am unsure how this relates to #multiplayer

[rain condor]

Because i'm trying to replicate this

in standalone works fine

[fossil spoke]

Ok well you never specified that, probably should have led with that context.

[rain condor]

But on mp when i remove an item, only dissapears vissualy

[fossil spoke]

Is RemoveItems only called by the Server?

And you are relying on Replication to see that change on the Client?

[rain condor]

I used a custom event to call on sv

And then i used an event dispatcher for client

[queen escarp]

morning guys, im trying my luck here again

https://gyazo.com/3ee621c813896c5890d3017a196040b6

why is there no debre spawning on the left side (server) but on clients it works ?

[velvet kettle]

best guess with little info, you are spawning it on the client, not the server

[queen escarp]

this is how its being played, its run with a rpc so should affect all

o wait that wrong

https://blueprintue.com/blueprint/387pu-r3/

use doodas is a server event*

[velvet kettle]

when in doubt, throw in print strings and HasAuthority nodes

[queen escarp]

aye but since its the server replicating it to clients then it cast go past the server since rpc can only be done from server O.o ??

[velvet kettle]

RPC is From Client to Server

[queen escarp]

oh right thats true,

well its prinitng both from server / client

the weird part is that its "working" but only halfly *

[velvet kettle]

also if you are going to want the explode range to be the same on client and server then you need to pass that Random float result through, not just store it on the variable. even if it is a replicated variable, there is no guarantee it will rep fast enough for the client to have the same value

[queen escarp]

true

i only did that to se if it was related to the debree but it wasent so

[velvet kettle]

if the event is being called by the actor on the server side try just using a mutlicast event

then you can avoid an RPC

[queen escarp]

i was just about to try that

nah no help..

ohh i think i got it

[velvet kettle]

if it was my thing, i would try... Multicast Event -> HasAuthority (Server) - > Remaining Logic

one last advice, since it is just cosmetic in nature, don't make your Event reliable. it is a waste of network

[twin juniper]

u mean unreliable

[queen escarp]

it is unrelieble

its not relieble

i had the same thought

[velvet kettle]

no, i said dont lol

[queen escarp]

but if i make it reliable then it cost more networking ??

[velvet kettle]

this should help with the confusion

[queen escarp]

🫡

[velvet kettle]

🤣

[queen escarp]

hm doing it your way with rpc < has authority < logic

dosent work since it only happens on the server (with same bugg) its not replicating, physics aint replicated i think someone said ?

yeah when i said it it got me thinking, removing replicate make it work on the server

since this is an instance thats needs to be run "localy in a sense"

yepp now everything works

noice

[normal valley]

i was wondering what kind of solutions people have come up with too replicate chaos vehicles nicely. out of the box i am getting lots of jitter (i guess this is down to lack of client side prediction?)

this looks like an interesting pack, does anyone have experience with it?
https://www.unrealengine.com/marketplace/en-US/product/advanced-vehicle-system

[lost inlet]

Fully Network Replicated (Client Authority Model)

well, anything is possible if you let the client cheat!

[normal valley]

great point

[lost inlet]

Epic is working on physics prediction but I'm not sure how well it integrates with the Chaos vehicles

[chrome bay]

chaos vehicles are client auth by default so long as you own/possess the vehicle you're driving. I wonder if this is where people are going wrong with it

[swift turret]

looking for a good idea how to replicate "movement" while playing montage with root motion.

Problem: i have an attack ability (not GAS unfortunately, cant change that), ability plays montage on client and server (local prediction). But then during ability player can press WSAD and change direction of attack. And here is the problem. With LAG = 200ms player just teleports in different directions if i press WSAD really fast. Client calculates rotation, set it locally and sends it to server. Server changes it, but becuase its late 200ms and because montage is playing, server during that time sends to local player his corrected rotation and it destroys input im pressing. Any ideas?

[twin juniper]

I have a cube placed in the level and this code, but it didn't run (as nothing printed)
Any idea?

Should be something like this, right?

[swift turret]

the cube placed on level is owned by server, so calling Server RPC from client will do nothing

you would need to move Server func to something client owned, like Player Controller

you are calling SetOwner, but you are calling it everywhere

even on server, so server sets itselfe as owner, and client tries to set itselfe (not sure if client even can change owner)

[twin juniper]

if i do this it didn't run either

[swift turret]

well yes, as i said, you need to setup owner on server but to client xd

getr player controller always returns local player

so you need to use smth else but on server side

[twin juniper]

ok, thanks

[rain condor]

I have an inventory where each tile is part of an array. To remove an item from the inventory, I leave the index empty so I can reuse it. The problem is that when you remove it you only do it visually and the tiles it occupied still cannot be used. This works fine on standalone but i'm trying to replicate it

[split siren]

UReplicationGraph::IsConnectionReady function is called during UReplicationGraph::ReplicateActorsForConnection where if it fails, it says it exceeded the budget for this category.

Where are the budgets for each connection defined?
Do I understand it correctly that if the budget for a given connection is exceeded, the "remainder" that has exceeded the budget is stored in Connection->QueuedBits or Connection->SendBuffer?

// UReplicationGraph::ReplicateActorsForConnection
if (IsConnectionReady(NetConnection) == false)
{
    // We've exceeded the budget for this category of replication list.
    RG_QUICK_SCOPE_CYCLE_COUNTER(NET_ReplicateActors_PartialStarvedActorList);
    HandleStarvedActorList(*ConnectionManager, PrioritizedReplicationList, ActorIdx + 1, ConnectionActorInfoMap, FrameNum);
    NotifyConnectionSaturated(*ConnectionManager);
    break;
}

[twin juniper]

What you are saying is SetOwner won't work on client side, but why does this code still run

what was the problem with my previous code? i don't really catch what you mean

[thin stratus]

What PlayerController do you think is GetPlayerController getting here?

[twin juniper]

the local one as it print on the screen?

[thin stratus]

Sure, but SetOwner has to be called on the Server

Client calling it has 0 effect

[twin juniper]

i never read any document about that though. I am not saying i dont trust you, i just need to verify information, do you have any

[thin stratus]

The Engine's Source Code?

RPCs require Ownership of the Actor by the Client

If you set the Owner locally, the Server will know nothing about it.

Otherwise the whole idea about Authority would be down the drain

The "Actor in Scene" problem will always require you to RPC in a Client-owned Actor first

Such as your Character

Unless you handle it via an Overlap fwiw

[twin juniper]

the source code didn't have any authority check though

[thin stratus]

The RPC is the problem, not the SetOwner itself

The RPC is dropped by the Server if the Client doesn't own the Actor

If you set the value locally, the Server doesn't know you own it

[twin juniper]

so SetOwner is like a multicast?

[thin stratus]

No

The Owner variable is replicated fwiw

[twin juniper]

oh, now it all make sense

thanks

[thin stratus]

It's tricky to give a better example for your Cube problem, because I don't know what the player is supposed to do with the cube

But in most cases, the issue you face is the same that everyone with an Interfaction System faces

Which is that interacting with something in the World would need to replicate

And for that it needs to be done on the Server

And since you can't call ServerRPC on the Actor in the World, you gotta do it in the Character

[twin juniper]

i dont really care about the cube, i am just trying to understand ownership through experiment

[thin stratus]

And then access the Actor (Cube)

But you read the Ownership stuff in the Docs and the Network Compendium?

[twin juniper]

but yeah i was trying to print something

yes i did read, multiple time, but mp is tricky still

[thin stratus]

Fair enough

[twin juniper]

i dont think you mentioned the ownership can only be set in the server

[thin stratus]

Ownership is luckily really simple. One Player at a time can own an Actor and the Server is the one who has to set a player as the owner.
Ownership then controls replication stuff such as:

• Being allowed to ServerRPC
• Receiving the ClientRPC from the Server
• Using Replication Condition on Variables that have to do with ownership

Freaking autocorrect

[thin stratus]

Could be, it's easy to forget that some stuff isn't always clear

I will see if I add that in the future

I think Epic could do a better job on the SetOwner function comment too

[scarlet nova]

hi! Is it possible to replicate map values?

I had a struct that has map value inside, but the map does not transfer with the struct on Run on Server calls, it's just null on the other side.

[twin juniper]

wtf

i was going to ask the same question rn

[scarlet nova]

hahaha

[twin juniper]

was going to run my code but apparently TMap is not supported

[scarlet nova]

nooo, why it's not supported

😔

I have to make a converter now, I guess

[twin juniper]

it really is a weird design when TArray is ok but TMap is not

[scarlet nova]

yeah, people say that it was working like a couple versions ago

and suddenly it doesn't work again

weird

https://forums.unrealengine.com/t/how-replication-map-values/418347

[woven bramble]

Guys, I have a big problem.
When someone enters (or exits) the room (or in the game already, doesn't matter), they get kicked out (or disconnected) of the game, and after being kicked out, they cannot enter the game again, and the find room/lobby doesn't work.
So after the disconnecting, although the internet is connected, it behaves as if there is no internet.
Either when someone sends an invite to this person in the game (and the person accepts), the problem is completely resolved, or when you close and reopen the game.
What could be the reason for this?

This problem occurs very rarely and I have been having the same problem for 1 year. I really couldn't find a solution. My game is about to be released.

[twin juniper]

idk anything about ur problem but nah, having a bug for 1 year is wild 💀

[pastel reef]

[scarlet nova]

you have to leave session to join/create/find sessions

maybe your problem is something about that

[woven bramble]

Of course, there are already end sessions, find sessions, etc. in the game.

[solar stirrup]

@scarlet nova @twin juniper you can replicate maps if you override struct net serialization and implement it yourself

[twin juniper]

no thanks

too hard for me

https://tenor.com/view/fuck-this-shit-im-out-out-of-here-leaving-annoyed-gif-16132712

[woven bramble]

Would you recommend me to add these to the config?
Engine.ini
[/Script/OnlineSubsystemUtils.IpNetDriver]
MaxClientRate=120000
MaxInternetClientRate=120000
InitialConnectTimeout=300.0
ConnectionTimeout=300.0

Game.ini
[/Script/Engine.GameNetworkManager]
TotalNetBandwidth=104857600
MaxDynamicBandwidth=104857600
MinDynamicBandwidth=10485760

Scalability.ini
[NetworkQuality@3]
TotalNetBandwidth=104857600
MaxDynamicBandwidth=104857600
MinDynamicBandwidth=10485760

[woven bramble]

For this problem.

[thin stratus]

"the room"?

What room?

[woven bramble]

lobby

so, I mean "session

[thin stratus]

Right

Just the Session, not the Server?

@twin juniper @scarlet nova just fyi, TSet is also not supported. Iirc it's due to being not performant to replicate those.

[twin juniper]

https://tenor.com/view/unreal-engine-5-in-le-head-unreal-gif-7200992705667229569

[thin stratus]

@woven bramble Overall I'm not too sure what kind of setup you have where a player Leaves or Joins Sessions while not also joining the Server and leaving it.

The issue itself sounds a lot like you aren't cleaning up the Session when disconnecting.
It should still find Sessions however, but would fail Creating and Joining them.

If you need to debug this you should properly breakpoint the C++ part and see where it fails.

I don't think the ini file will do anything about this.

[woven bramble]

In a Listen server, after establishing a session, I connect to the game. Most of the time, the game proceeds smoothly. However, in some cases, the user suddenly disconnects from the game. It cannot establish or find a session. When I send them an invite again via Steam, they can rejoin the game. In fact, they can also create/find rooms as they wish after the accepting the Invite. I'm using Advanced Session.

Are you referring to resetting the Join Session/FindSession values ​​(variables) created by the Game Instance, for example?

[thin stratus]

No I meant DestroySession call

You will need to debug it

I don't think anyone would really know a solution

This is a matter of hooking up your VS to it and breakpointing the Find Session logic to see why it fails

Randomly disconnecting is also strange

You'd need to look at the Logs for that

[woven bramble]

I can't do trial and error method because it's very rare. Also, there are no logs because it's a package already available on Steam. or I don't know how can I look the debugs

[woven bramble]

My last question is, do you recommend me, creating a Destroy Session when it get to the main menu? Does this make sense?

[lilac lance]

if I Call SetActorLocation in the server, will it automatically replicate to the clients? or do I need to call Multicast RPCs for that to work?

[vestal shale]

How to replicate sounds and particles ?

[mystic estuary]

A way of doing that is fire an RPC that does that

[vestal shale]

Server, Client or Multicast ?

And Example would be perfect

[mystic estuary]

It depends where you want to play these effects. If you want everyone to see them, you can do a multicast. If you want a particular client to see that, use the client RPC. It all depends on your needs

[vestal shale]

I want all clients to see that

[mystic estuary]

Then use a multicast RPC. Since the cosmetics are not important, and missing a sound wouldn't affect the logic in any way, the RPC should be unreliable

[vestal shale]

I tried that

The FX is only visible to the owning client

No others

Why is that

[mystic estuary]

Most likely you're firing the multicast from a client, not from the server. Clients can only call server RPCs, while server can call anything. Calling an RPC a client cannot call will fail.

[vestal shale]

Then how do I call that RPC from the server to all ?

One server RPC and from there call Multicast RPC ?

[mystic estuary]

If you're starting the logic from a client, then you need to do a server RPC, which in turn will do a multicast RPC

[mystic estuary]

Correct

[vestal shale]

Let me try

Works

Thanks for your time

[mystic estuary]

🥳

You're welcome

[vestal shale]

But I got issue

I tried in Blueprint. It works

But from C++ it doesnt

What could be the issue

@mystic estuary

[mystic estuary]

Most likely in your C++ code. Can you show it?

[mystic estuary]

Is the class that you do that from the same as in BPs? What is it?

[vestal shale]

No, in BP its the character class

[mystic estuary]

Character is owned by the client, while your weapon most likely is not, hence you fail to call a server RPC, as the client does not own that particular actor

[vestal shale]

How do I make work then ?

[mystic estuary]

You should make the weapon be owned by the client, so that you'll be able to call your server RPC. I cannot recall how you do that exactly though 🤔 Trying to read through the networking compendium to find out the answer

[vestal shale]

By changing actor ownership or any other means

[mystic estuary]

Each Connection has a PlayerController, created specifically for that Connection. A PlayerController, that is created for that
reason, is owned by that Connection. So when we determine if an Actor is owned by someone, we actually query up to the
most outer Owner and if this is a PlayerController, then the Connection that owns the PlayerController also owns that Actor.
The Pawn/Character. They are possessed by the PlayerController and at this time, the PlayerController is the Owner of the
possessed Pawn. This means, the Connection that owns this PlayerController also owns the Pawn.

I'm not sure, but you might need to specify the PC as the owner (or maybe even instigator, but I don't think so) when you create the weapon

Like that

[vestal shale]

So, lets say when I equip the weapon, I set its owner to the player controller of the player who owned it. Will that work ?

[mystic estuary]

I have never changed the owner of the actor on runtime, however, you should be able to since character and pawns do that. You might need to look up for the way it's done. It should be something down the chain when the OnPossessed is called

[vestal shale]

I will look into that then.

Thanks

[thin stratus]

Yeah I usually have that in the GameMode for the MainMenu

Cause I know the Player (in my case) should not be in a session

Others simply plug DestroSession infront of their Find/Join/Create node

[vestal shale]

Hey Cedric, can you help ?

[thin stratus]

What exactly is the issue?

It looks like you already got help

[vestal shale]

So I have a weapon, its has VFX as usual

Which I want to be played on all clients

I cannot send RPC from the weapon actor, since its not client owned

I wanted to know if changing weapon actor's ownership will be good way or send the RPC via the PlayerCharacter ?

[thin stratus]

That's multiple problems

1. Having the Weapon owned by the Player(Character) is a good choice

That way you can call your ServerRPC to Fire the Weapon, Reload the Weapon, etc. inside the Weapon.

2. To execute something "on everyone", you need a Multicast, and Multicast doesn't require Ownership, it simply has to be called by the Server.

So if you, when spawning the Weapon (on the Server!) supply the Character as the Owner, then you should be able to call Server_FireWeapon on it just fine.

And if the result of that Server_FireWeapon is to play VFX on everyone, you can call Multicast from it

This is of course without any prediction in mind, but gotta start somewhere.

[vestal shale]

Alright. I will try what you said

[solar stirrup]

I can't wait to try out doing shooting through the movement component

feels like it'll make prediction so much simpler

[thin stratus]

@solar stirrup Mover 2.0 creeping up slowly.

[quasi tide]

Very slowly

[solar stirrup]

Moved to the GMC

Latest update allows custom sync types so I can now bind FInstancedStructs to my move data

https://tenor.com/view/unlimited-power-star-wars-gif-10270127

[thin stratus]

Just be careful you don't overfill it

[solar stirrup]

Yeah ofc

I plan to have the client send whether or not it's shooting and hits up to the server

Server response can probs be done outside

I'll see after stress testing

but paired with the GMC's rewind stuff, oooooh mama

it's gonna be spicy

[pallid mesa]

jahahaha this is mean

[solar stirrup]

[pallid mesa]

blep

projectile interpolation in the pmc works v sweet btw

[solar stirrup]

gmc or cmc

[pallid mesa]

has there been any tutorial out there explaining how to set it up?

i could make one

pmc*

[solar stirrup]

pmc?

[pallid mesa]

projectile movement

[solar stirrup]

is that vanilla unreal

[pallid mesa]

yes

[solar stirrup]

awesome, gonna put it on my list of stuff to look into

[pallid mesa]

it does verlet

[solar stirrup]

i plan to use hitscans for most close range shots anyway

[pallid mesa]

ye but erlite don use pmc

do ur own projectile system

[solar stirrup]

why

[pallid mesa]

cuz using actors for projectiles kinda suck

i do it cuz projectile count is v v low

but if ur game gonna do projectiles real good

do something nice, like s world subsystem implementing arc trajectories

and trace between throttled updates

u can also predict them v easily

[solar stirrup]

how replicate

[pallid mesa]

the server only needs loc/rot

[solar stirrup]

client cosmetics?

[pallid mesa]

and from the server u can multicast some cues

using this loc/rot data

[solar stirrup]

what about tracers

[pallid mesa]

yea if ur projectiles dont have gameplay interactions other than impacts

u can use ur static projectile data to know in the client how traces look

[thin stratus]

The only beef I have with the PMC is the amount of stuff you gotta do around it to make it work

Partially not even exposed to BPs

[pallid mesa]

think that given a rot/loc + static data u can do whatever

[pallid mesa]

ye

[solar stirrup]

relevancy becomes an issue

I don't want cheaters using projectiles to guess where players are

[thin stratus]

Like

[pallid mesa]

wym xD

[thin stratus]

/**
 * Assigns the component that will be used for network interpolation/smoothing. It is expected that this is a component attached somewhere below the UpdatedComponent.
 * When network updates use MoveInterpolationTarget() to move the UpdatedComponent, the interpolated component's relative offset will be maintained and smoothed over
 * the course of future component ticks. The current relative location and rotation of the component is saved as the target offset for future interpolation.
 * @see MoveInterpolationTarget(), bInterpMovement, bInterpRotation
 */
UFUNCTION(BlueprintCallable, Category="Game|Components|ProjectileMovement|Interpolation")
ENGINE_API virtual void SetInterpolatedComponent(USceneComponent* Component);

[solar stirrup]

How do you determine which players get what projectiles

[pallid mesa]

ah ye i was sayin that i didnt see any tutorial settin that up

[thin stratus]

Yeah because no one knows haha

There is a lot more to it

[pallid mesa]

many ways to do this

[thin stratus]

You should theoretically also forward the Velocity of the Actor to the PMC

Which you can't in BPs , at least not properly

[pallid mesa]

the postnetreceivelocandrot also exi

[thin stratus]

Yeah

[solar stirrup]

I mean I could send copies of the projectile data to different players but that sounds like a lot of work

[thin stratus]

I wonder why they didn't just make a Projectile actor tbh

And tie the PMC to it

It's somewhat shite idea

But better than this

[pallid mesa]

u can send s pointer to this net mappable data

or an index and then client-map it

there are more ways like.. have an actor associated with the gun and trigger its visuals from there ..

its gameplay code

u can be creative

[solar stirrup]

i mean yeah

gonna have to in the end :^)

just that with the rep graph actors are always simpler for relevancy

so this is gonna be fun

[pallid mesa]

yee right i will likely write a mini blog about how to set it up

[thin stratus]

Didn't Riot also write about the Projectiles?

On top of the characters

[pallid mesa]

cuz i was sockef it wasnt anywhere

[thin stratus]

I think there was something in their post about it

[solar stirrup]

still a bit pissed that rep graph isn't suitable for LWC

[pallid mesa]

erlite enable iriiis screw the repgraph haha

[thin stratus]

I mean, RepGraphis being somewhat phased out anyway

[solar stirrup]

if I have to modify the cell stuff im gonna be sad

[solar stirrup]

I wish

what's the state in 5.3

[pallid mesa]

ima be honest

it kinda works

kinda

[thin stratus]

I heard it somewhat works just fine

[pallid mesa]

ye

[thin stratus]

But one will have to wait for proper release to be sure I would say

[pallid mesa]

minus some bogus here there

[solar stirrup]

ehhhhh

[pallid mesa]

im usin it in side project

[solar stirrup]

I can take a peak but I doubt i'll be allowed to

[pallid mesa]

if its for ur job, dont

:v

[solar stirrup]

if it was my side project I'd be on ue5-main latest with it enabled

:^)

[pallid mesa]

HAHA

btw physics prediction works like a charm in 5.4

:^)

but its absolutely broken in 5.3

[solar stirrup]

good to know

although GMC doesn't support it anyway

[pallid mesa]

😩

[solar stirrup]

but it might be cool for vehicles if I ever wanna make some

tbh I doubt CMC supports physics too heh

[pallid mesa]

it does interact with

so it works as a "pusher"

[solar stirrup]

I think GMC works as a pusher too

i'll take a look later

[pallid mesa]

and well, ye Ragdolls

replicated ragdolls is v sweet

[solar stirrup]

ay

[pallid mesa]

but only root bone

i havent tried reping all bonez

[solar stirrup]

sounds painful bandwidth wise

[pallid mesa]

X'D ye

all bones ye

but chaos sleep calls work now™️

so u wont recieve physics state reps when the body goes to sleep in the server

so u can just "freeze"

[solar stirrup]

that's neat

[pallid mesa]

yee epic is working hard in chaos

🙏

[quasi tide]

Every time someone mentions iris, my question is always the same. What kind of benefits are we supposed to actually be getting? No benchmarks or target goals or anything like that has ever been provided.

[pallid mesa]

cpu performance improvements

thats the main benefit

[queen escarp]

Hey Question, im having the same problem as all mp rookies are having with the CMC for clients on listen server is jittering forward i dont know how to solve it, but i just cam across someone poininting out that i could try to set " bOnlyAllowAutonomousTickPose to false"

how would i do that with BP ? is that possible +

[pallid mesa]

not possible in BPs, no

:<

[queen escarp]

hm okey, but is this a common change to solve my issue that you are aware of ?

[hollow eagle]

The CPU perf improvement as it stands today is massive, and there's still a lot of potential stuff that they haven't even implemented yet (like threaded serialization).

they haven't provided any actual benchmarks because they haven't switched yet though I think someone said fortnite is moving soon?

[solar stirrup]

if Fortnite starts using Iris then we know for sure that it's solid

I noticed that they have been very aggressive with network optimisation in the latest Fornite season

Probs because weapons aren't as long range but like, I can see players cull out pretty close

[quasi tide]

Dang - was the old system really that slow 😅

[queen escarp]

@pallid mesa

where do i change bOnlyAllowAutonomousTickPose to false"

is it inisde the character c++ or Cmc++ ?

[pallid mesa]

yeah iris is like - pessimistically speaking x20

[pallid mesa]

not sure about the details, you might want to ask the in the post where u found that 😬

[queen escarp]

I believe I encountered the same issue in my game - unfortunately the only fix I could come up with involves c++.

In the CharacterMovementComponent source you'll see the following comment:

// If not playing root motion, tick animations after physics. We do this here to keep events, notifies, states and transitions in sync with client updates.

before a manual call of the animation tick, so the animation of remotely controlled pawns on servers only ticks at the rate of updates from those clients.

So it is possible to override that MoveAutonomous function to not manually tick the pose, and set it back to normal by changing your Character class mesh's bOnlyAllowAutonomousTickPose to false.

However they clearly had legitimate reasons for doing this, and there will surely be repercussions I haven't figured out yet.

As to whether or not this is normal I think listen servers are a bit of an afterthought in most of these project setups for Epic, on headless dedicated servers animation ticking generally doesn't matter (this bug only manifests on the server machine).

maybe this is not what im after even

[half drum]

working on a lobby system, my idea is to override the gamemode postlogin and logout functions so they broadcast a multicast delegate telling players to update their current player count in the lobby widget, does that sound like a decent way of doing it?

[solar stirrup]

That much???

[pallid mesa]

ye it goes brrr

[quasi tide]

Now imagine what could be achieved if they fixed the component transform system. Then @signal lance will finally find peace.

(Now BM is probably wondering why he has a red notification in #multiplayer 😈)

[solar stirrup]

What issue are you talking about

[quasi tide]

It's BM's holy war against UE

One that he will spend a lifetime waging on our behalf 🙏

[clear island]

is iris meant to be compatible with the current replication system? as in, its something to be used alongside the normal replication system?

[thin stratus]

It replaces it by more or less not breaking your game :D

[quasi tide]

It's supposed to be an as-drop-in-replacement-as-possible solution

But it's not marked production ready

[signal lance]

[quasi tide]

Mover 2.0
AnimNext
Iris

👆 Things I want 🙏

[signal lance]

this is the tldr #cpp message

[clear island]

thats awesome

I've held off on the repgraph and just been using push model, lets see if it pays off 😄

[hollow eagle]

it's also not-quite-drop-in, custom struct serializers need to be rewritten (though a lot of the situations where you'd need a custom netserializer are now entirely unnecessary)

and certain specific features are outright unsupported, like subobject net group conditions and the old ReplicateSubobjects method (which is old and icky anyway, the replicated subobject list is way better)

[solar stirrup]

Ah yeah

noticed transform updates are pretty expensive

subobject net group conditions
that's annoying, but do they provide an alternative?

[clear island]

nice, I'm not using any of that so far, I'll try to keep it that way

[hollow eagle]

nope

not sure if they're planning to implement it later or what

it might be doable with custom object filters though

haven't really looked into it

there's nothing quite as simple as COND_NetGroup though

which is kind of dumb because netgroups are a fairly recent thing, introducing them and then immediately making them useless is silly

[solar stirrup]

yea

[hollow eagle]

actually there's some sort of per-connection filtering API but it's not well documented. net object filters will work but again, not quite as simple.

[chrome bay]

Isn't NetGroup new to Iris though?

[hollow eagle]

no, it only works in the old system

[chrome bay]

ah kk

[hollow eagle]

hmm, actually my info might be out of date

it looks like at least in 5.3 there's some functions updating object filters that mention COND_Group (which I assume is a typo for COND_NetGroup)

not sure if it works though, will have to test it

[solar stirrup]

https://github.com/EpicGames/UnrealEngine/commit/810b845974310e95adf543c45f4620d52bcce748

 Iris

Increase max registered groups from 4 to 8

kinda looks similar

[hollow eagle]

that's what this seems to be leveraging

but it's not clear whether it actually hooks into netgroups yet

yeah, APlayerController::IncludeInNetConditionGroup calls into UpdateSubObjectGroupMemberships in iris

except... for some reason nothing actually tries to update subobject membership. So it's either intended that you call into FReplicationSystemUtil::UpdateSubObjectGroupMemberships manually after modifying an object's groups or it's just unfinished

[rose pollen]

is there a built in "teleport but try and adjust location" function similar to the spawn actor option to "try and adjust location but always spawn"? I have a blink ability in my game and am running into issues where occassionally the spot the player wants to blink to ends up intersecting with another actor and I want the server to adjust the TP location if the basic teleport fails. I'm wondering if I need to roll that code myself or if there is something built in

[solar stirrup]

UWorld::FindTeleportSpot() or use the Environment Query System

[pallid mesa]

is there a list of mappings? ie: old relates to new?

[quaint knot]

first day doing multiplayer in UE............ I'm considering doing UEFN 😂

[hollow eagle]

not really, aside from filtering, prioritization, and serialization everything else either works or is unsupported

and when I say serialization I mean custom, basic uproperty stuff works as always

[solar stirrup]

Iris' getting almost daily updates at least

well

at least for the last two weeks or so

progress seems to have been consistent so hopefully we get more news soon

[hollow eagle]

lol i tried to add an object to all of 2 netgroups and it asserted saying it was in too many iris groups

guess that explains why they bumped the limit in that commit

I guess iris already uses something like 3 groups ugh

[solar stirrup]

why even limit it

[hollow eagle]

perf

[solar stirrup]

i mean yeah i guess but that bad?

[hollow eagle]

wait this check is bizzare, this object isn't a member of any groups and it's complaining, wat

oh wait

it's a bug in iris, it asserts if the object is already in a group and you try to add it lol

but the message complains that you have too many groups

lol, they removed the assert entirely in main

just an extra log complaining that an object has high group membership. They might have removed the hard cap too.

Guess I'll just leave this off until 5.4 :/

[solar stirrup]

yep

    struct FNetObjectGroupMembership
    {
        enum { MaxAssignedGroupCount = 8 };
        FNetObjectGroupHandle Groups[MaxAssignedGroupCount];        
    };

before

    struct FNetObjectGroupMembership
    {
        enum { NumInlinedGroupHandles = 2 };
        TArray<FNetObjectGroupHandle, TInlineAllocator<NumInlinedGroupHandles>> Groups;
    };

now

seems like they just don't care about group count anymore heh

[hollow eagle]

they do, they have a warning in logs now

[solar stirrup]

oh

what does the warning say

[hollow eagle]

"you have lots of groups lol"

previously they just asserted

[pallid mesa]

"QUANTIFY THAT!!"

lots

haha

[solar stirrup]

static int32 CVarEnsureIfNumGroupMembershipsExceedsNum = 128;

is it a net object with 128 groups or just 128 groups in total

[hollow eagle]

it's an object in 128 groups

there's no limit to the total group count afaik

[solar stirrup]

i guess it makes sense

dunno why you'd shove an object in so many groups

[flat halo]

Hi, is there a way to make the Find Sessions node work with VPN LAN?
I am trying to integrate OnlineSubsystemNull and Sessions.
Before I was connecting by typing the IP and it was working for LAN and VPN LAN.
But with Sessions I am not being able to see the sessions.
I tried with OpenVPN and also Hamachi.
I tried with the bIsLan flag checked and unchecked, both for hosting and finding sessions.

Thanks.

[livid jetty]

I run this from menu level, it fails with error:
CreateSession - Invalid player state
How do i change player pawn before creating session ?

But i want to change pawn only OnSuccess

[mystic estuary]

You didn't specify the player controller?

[livid jetty]

I just use default "Character" for camera UI in MainMenu level

[inner cove]

Hey guys. What's the best way to determine if a code is running on an owning client? The server does a multicast but the owning client must not run the code as it has already run it locally

[mystic estuary]

I'm saying that you get the "CreateSession - Invalid player state" because you're missing a PC. If you want to dynamically tell the game what pawn it should spawn by default, take a loot at the GetDefaultPawnClassForController inside the game mode

[livid jetty]

I have player character prepared with custom CMC, i just want to switch it when session is up and ready

maybe i need to create networked "lobby" character only with camera and then switch it ?

[mystic estuary]

If at the moment that you hit the CreateSession you already have a spawned character, then you need to destroy it, spawn a new one, and possess it using the associated PC

[vestal shale]

What will be the result of this IF STATEMENT

[solemn dirge]

hey guys, anyone have any idea why my server browser isnt displaying advanced sessions ?

The find sessions function isnt failing, I'm not getting the print string. But I am getting the refreshed message

[fossil spoke]

What do you mean?

The result if True will be that it exits the function due to the return statement

If its condition evaluates to False, then the Fire function will be called

[vestal shale]

I actually wanted to exclude the client who performed Multicast RPC from server

So I found that piece from somewhere. Wanted to know the meaning

Anyway, I understood

[fossil spoke]

Its useful to not use single line conditions followed by statements

if(Condition)
{
    Statement
}

Instead of

if(Condition) Statement

Much easier to read the first

And reason about it as well.

Try and follow Epics coding standard.

https://docs.unrealengine.com/4.27/en-US/ProductionPipelines/DevelopmentSetup/CodingStandard/

[vestal shale]

I know. But coming from out of Unreal Ecosystem. Got used to not using braces for one liners

[fossil spoke]

Personally, I think its lazy and poor form. But generally you should follow the standards that have been set before you.

If I moved to a code base where single line was a precedent, then I would conform.

[languid bridge]

I've been trying to use Advanced Sessions plugin all day and as far as I can tell it just doesn't work. I can't even get it to return listen servers on LAN, and it doesn't ever seem to actually call Start Session. (Though it also looks like you don't have the Results array plugged in to your ForEach loop)

[solemn dirge]

Thank you for this, I did research and apparently steam sessions only work if another computer has access to the client. I'm packaging right now and sending to another pc to test, If i remember ill keep you posted

[languid bridge]

If you can figure out LAN sessions with it or point me in the right direction, that'd be cool too. I can get Listen servers to work on LAN with the regular session control nodes, but I can't get dedicated servers to work the way I want on LAN, and I can't get either of them to work on LAN with Advanced Sessions.

Ah, hell, I'm a dummy. Turns out 'should advertise' is real important to have ticked. Now I can get both server types to work.

[solemn dirge]

and you didnt package the product?

are you using advanced sessions or default nodes

[languid bridge]

Yeah, without packaging, using advanced sessions. But I'm using null OnlineSubsystem and just testing LAN.

[twin juniper]

Can i create widget at the start of the game by doing this at BeginPlay of PlayerController?

i have 2 players but only the Server player's RPC is going through

i guess it could be because client side's PlayerController didn't exist yet, so the RPC wouldn't be run

shouldn't it be waiting or something, or this is intended behaviour?

i guess ill just call a normal function but onrep_owner

[twin juniper]

2 - I have another question too, say i have a cube on a machine, can a pointer on another machine which is pointing to that cube, get variable out, or even exist (!nullptr)

i mean like pointer to the exact cube, is it possible

[nova wasp]

an RPC/replication packet sending over an object pointer will turn it into the other client's local object pointer if it is replicated etc

[twin juniper]

i mean the cube on the original machine

not the replicated one

how do i phrase this

[twin juniper]

Hmm my RepNotify didn't run on the server, i used it to update the widget each time an item changed

Client RPC worked though

is this intended behaviour that RepNotify didn't run on server player?

that's weird

actually not weird because the server's variables is not replicated at all

hmm

[weary saffron]

Hi! Please tell me exactly how variable replication works.
Does the server constantly send the current value of the variable?
Or does the client send an affirmative response back to the server about receiving the value of the variable to stop sending?

[chrome bay]

The client acks the change eventually yeah

[twin juniper]

should i turn on network emulation all the time, to know what is the right thing to do?

turned it on but it make my client movement very glichy, not sure if that is how it should be

[chrome bay]

Shouldn't be that bad. If you're running the editor at very high frame rate however it will cause problems. Look at the logs to see if any warnings are present.

[nova wasp]

in-editor network emulation is reaaaally way worse than reality's common case (bad definitely is imo)

1% packet loss is quite a lot and you might even have ~300 ping here lol

this is like "does my game come apart at the seams when mom turns on netflix" testing

[twin juniper]

you are right, i turned on Capsule replicates for some reason

turned it off, now it's smooth

[chrome bay]

Internet: Challenge Accepted

[twin juniper]

my level is reload when RPC validate return false lol
This is my first time using RPC validate, is this what it suppose to do?

i thought it gonna just cancel and do nothing

[chrome bay]

Returning false will kick the player immediately.

_Validate is meant for things like cheat detection / validating input params etc. Generally speaking it's usage is actually quite limited due to the lossy/latent nature of MP

[twin juniper]

🤔

[chrome bay]

If you want to handle it gracefully/softly you just early out in the _Implementation as normal

[twin juniper]

yet we have a validate for every single server rpc

[chrome bay]

You don't have to

[twin juniper]

really

[chrome bay]

Just remove the WithValidation part of the declaration

Or you can just return true, which is what most do.

[twin juniper]

i dont think that's possible

[chrome bay]

Try it

Then remove the function declaration if you've declared it yourself

[nova wasp]

yeah... it's just constantly bad though bs randomly bad

[chrome bay]

main thing is you just want to make sure the game can recover eventually, i.e. it's still playable even if the experience is terrible

bonus points if you can make the experience not terrible though

[twin juniper]

it actually worked

bro i swear the document is a lie

[chrome bay]

Where is that from?

[twin juniper]

https://docs.unrealengine.com/5.3/en-US/rpcs-in-unreal-engine/

**r e q u i r e **

[chrome bay]

Validate funcs have been optional since like 4.15

Unreal Documentation being almost always out of date or just complete nonsense is common knowledge unfortunately

Although that page in particular seems to have some blatant formatting issues

Anyway all that aside... validate functions are really just to make sure the client isn't sending utterly nonsense data, but it's important not to be too over-zealous otherwise clients can be kicked purely because they don't have the latest state etc.

[thin stratus]

Really?

I could swear it wants you to have a Validate function even if not using it

[chrome bay]

yeah it was a loooooong time ago they removed the requirement

[thin stratus]

That confuses me, I could swear that requirement was still a thing when I worked on The Ascent, which was 4.26+

UFUNCTION(Server, Reliable) is enough then?

[chrome bay]

Yeah, then just don't declare or implement the _validate part

[thin stratus]

Hm, looking through a 5.0 project, all Server RPC have WithValidation. Maybe muscle memory

[chrome bay]

Yeah, tbh most of mine still have it 😄

[nova wasp]

it's not a bad idea to just make an empty one ahead of time I guess?

[thin stratus]

I never used them tbh

Like, never

I see their benefit

But never found a usecase

[chrome bay]

yeah very rarely for me, have used them a handful of times but definitely not for everything

[thin stratus]

99% of a the time, the Client doesn't send anything to the Server, and when it does, it's nothing to disconnect for if it#s wrong

Would probably be good to have a proper usecase

Could add that to my docs

Cause I don't think I have an example there

[chrome bay]

I've used it for weapon firing but that's all i can remember off the top of my head

[thin stratus]

Hmpf m,y docs also stil lsay WithValidation is required

I'm out of date

How dare I

[chrome bay]

tbh now everyone just uses GAS for everything I imagine it gets used less and less

[thin stratus]

That reads like you are annoyed at that?

Should I write a quick GAS presentation to cheer you up?

Pretty sure you ranted about this on Twitter already haha

[chrome bay]

I like GAS but it's a square peg being jammed into every shaped hole atm

Cues are the same, blunt solutions for specific problems

[nova wasp]

I wonder if they knew how widespread it would get back when making Paragon

[thin stratus]

That's true, but one of the reasons for that is that sometimes it's the easiest alternative to not using GAS

[nova wasp]

if they would have at least made some things less insanely hard coded lol

[chrome bay]

I guess I'm just not a fan of 'lets solve everything' things 😄

[thin stratus]

If the rest of the Engine would feature more lightweight solutions, it would probably be more ignored.

[nova wasp]

it really is a good idea for many things but MAN it's just so awkward sometimes lol

[thin stratus]

The only problem about GAS for me is the Prediction Code

[nova wasp]

I looove having duplicated negative predicted effects

[thin stratus]

The prediction code is really not great. It feels so half baked

[nova wasp]

hey, worked for the Moba they made

[chrome bay]

I'm just bitter since I had to write my own attribute system recently and it would have been nice to leverage at least some of the lower-level types in GAS but bleh

[thin stratus]

Yeah and the MOBA I work on struggles due to it

So not sure what they all hacked together

[thin stratus]

Some stuff is being moved out of GAS iirc

[nova wasp]

iirc the plan is to rip out the nicer more generic parts (tags etc?) based on engine commits to let others use it without the rest but I don't know

[thin stratus]

Such as GameplayCues?

Tags are already not part of GAS iirc

[chrome bay]

But the as-of-yet unannounced project I worked on last used GAS everywhere and it was actually beneficial for that project. But current project not so much.

[nova wasp]

no, but gameplay effect rules and the state machine they create kind of is

tags are generic of course

[thin stratus]

@chrome bay You know what's really bad? That Lyra uses it and people use Lyra for everything as a base.

[nova wasp]

I misspoke

Lyra has some awesome ideas and some very "oh god" ideas for anything that isn't a mega sized project

[chrome bay]

Cues, the extra gameplay tag stuff and the prediction stuff can be used generically. Very annoying that it's locked into GAS atm, but yeah they are meant to be changing that.

[thin stratus]

We have a customer with a party like game, bit more couch coop, N64 times fun with jumping around, collecting some power ups, and stuff.
And they use Lyra and thuse all the GAS stuff

[chrome bay]

I do like GAS generally speaking, just some areas could really do with being updated and/or less locked down. But I also think folks generally tend to do literally everything inside it rather than supplement it where needed, and it gets quite cumbersome

[thin stratus]

Just give me proper prediction

And I would be super happy

Let me pass data to the Server ActivateAbility call

Ensure GE actions are all predicted

Ensure the Movement stuff ties into it well

Movement Buffs shouldn't be such a pain

[chrome bay]

Yeah interlocking it with movement is probably never going to fully happen I suspect

[thin stratus]

Well, Movement is going to use the NPP

afaik

[chrome bay]

Problem is movement needs to operate on it's own frequency, and anything affecting it needs to be in lockstep with that or it all goes out the window

[thin stratus]

With Mover 2.0 I suspect

But GAS is not gonna be updated to use it I bet

[chrome bay]

yeah doubt it

[thin stratus]

I would say it's better to have ONE system in the back of all of them

[chrome bay]

I don't know if it can be solved generally, unless you have complete game state prediction and rollback

[thin stratus]

Overwatch shows that it's easy enough

One just can't start making multiple systems

With different features

The SavedMoves and all the logic around them would need to be extracted

NPP basically

So GAS and CMC can push to it and be controlled by its corrections

[nova wasp]

I'm trying my hand at a "sort of" rollback style setup with fixed ticking from scratch in order to that "just write the damn ability" setup

[thin stratus]

The beauty of that working hand in hand

[chrome bay]

yeah, but I cant even begin to imagine how badly that scales too

[thin stratus]

I'm sure this can be coded to scale well

Epic has the brains for that

But not the priorities

;_; Some nights I dream of the Debug Tools the NPP has

[chrome bay]

The troubling part is prediction and rollback of the entire game state, and not everything can be trivially resimulated

[nova wasp]

of course not, so I'm replacing it all lol

[chrome bay]

I can see that being incredibly hard to solve at a generic level

[nova wasp]

I'm expecting to have to throw up my hands and go back to regular old snapshot style eventually

[chrome bay]

Were you can just code things however you want and the engine goes "yeah k then I can cope iwht that"

[thin stratus]

I mean it would be mostly opt-in, right?

You only use it where needed. In most cases CMC and GAS would be the only things using it

[nova wasp]

ideally yeah

the CMC is already a tiny fixed ticking sim

[thin stratus]

GAS fully replaces any kind of Weapon Logic anyway

And if GAS isn't there, then the small ssystems like shooting a weapon aren't gonna impact it

[chrome bay]

I think also it's partly that all those systems then have to work in lockstep, CMC and GAS activations etc. would all have to be fully syncronised

IDK, it's a tough one. Maybe they'll find a solution one day but IDK.

[thin stratus]

That is correct, they need to use the same Timestamp on client and server

I don't think they will, but NPP and Mover 2.0 goes in the right direction

[chrome bay]

now add physics on top

[thin stratus]

No

[nova wasp]

everything to do with creating the "container" to send over is so bananas, it's frustrating to not have one holy blob of stuff as the input and have to pray rpcs come in on the same packets

[chrome bay]

At least the physics side of networking has gotten way better out of the box 😄

Definitely not bitter I spent years doing that myself

[thin stratus]

The sad thing is that I thought about driving Ability Activation via CMC a bunch of times

[scarlet nova]

hi there! Is there a node like "Is Owner" similar to "Is Server"?

[thin stratus]

Depends on the Actor and reason

Possessed Pawns and Characters have IsLocallyControlled

[scarlet nova]

that's what I needed, thanks a lot

[thin stratus]

Other actors would need to get the Owner and simply check

[nova wasp]

each actor CAN have a defined Owner but this is generally relegated to PlayerControllers/Pawns etc

you might be more concerned with local roles and netmodes etc

[thin stratus]

If you are strict with what you pass as the owner, you can also expect certain Owners to be Characters and cast them to use IsLocallyontrolled again

[twin juniper]

why pawn have that but playerstate dont though

strange design

[thin stratus]

PlayerState has an Owner

Ah you mean IsLocallyControlled

[scarlet nova]

do AI controllers have the server as owner btw?

probably no, but still asking :p

[twin juniper]

yeah

[thin stratus]

PlayerState's Owner is the Controller @twin juniper
If it's invalid you are on the SimProxy. If it's valid you can check the Owner (by casting it to Controller or PlayerController) if it's locallyControlled.

So in theory it has it, just with some extra steps

[chrome bay]

tbf this is basically what unreal tournament did to get such good prediction/rollback with their weapons etc. It was bloody awful to look at but it's a very specialised solution to a specialised problem

[thin stratus]

Thery are owned by the Server, yes. I don't actually know what GetOwner would return here

[thin stratus]

Yeah but now what is the difference to extracting this system into a centralized place ,and then using it?

[chrome bay]

People spend so much time what-iffing about future features they might want they're too afraid to write non-generic code.

[thin stratus]

Basically making it more accessible

[chrome bay]

Yeah but in part I think that's part of our problematic game dev culture where we want to solve all potential problems with one system 😄

I say this as someone who partakes btw 😄

[thin stratus]

True, buuuut this is also a bad example because here you'd really want one system that ticks in sync

[nova wasp]

I dislike how rollback is explained

it makes it seem like it's doing some crazy heuristic to guess what buttons you would push

when it's literally just "the same input repeated" most of the time

[thin stratus]

In theory, Prediction and Rollback is super simple

There is just a bunch of boilerplate sh*te needed to support it

E.g. stuff to ensure the Timestamps work properly

And then the layer of cheat protection on top

E.g. that stuff that Epic has disabled by default on the CMC 🙄

[nova wasp]

of course life is easier when the game state is a bunch of ints in street fighter 2 or whatever (insane emulation fun aside)

[scarlet nova]

meanwhile suffering inside the pile of structs, maps and arrays

[real ridge]

EOS servers are again down?

last week EOS was not functioning and I am having problems again since yesterday

[twin juniper]

I kinda finished my inventory system and now i am having an annoying delay, because everything is run on the server then replicated down
Should i make a custom prediction system or something? How do you guys normally do this?

like when drag and drop item in inventory, it go to server to check if there is enough space, then it go back to client to display

Maybe f*ck this, im not AAA studio so i let this as a feature

Slow paced game anyway

[thin stratus]

@twin juniper This is indeed the point at which you'd need to add prediction

There are multiple stages to this, the first would be to simply perform the action locally already

The next stage would be only replicating it back to the client if the Client did something that the Server deemed wrong.
So you'd tell the Server in the RPC what the Client did and if the Server can't do the same, send a correction, otherwise do nothing (or ack the whole thing)

But honestly, doing it locally first should already be fine

[twin juniper]

..unless someone cheated, right

so prediction, got it, i'll figure it out someday

thanks

[thin stratus]

since your game does everything on the Server, there is no "cheating" in the regard

The Server would only perform the Action, not accept the results

You tell the Server "I moved Item from Slot X to Slot Y and my result is that it worked."
And then the server does the same.

If the result says "doesn't work" cause there is an item in the way, it sends the latest state back to the Client and corrects the UI

[twin juniper]

but what if before the server send the correction, the player chain another action in based on the result of the previous one

and they chain a bunch of locally executed actions

then the server correct all of them?

maybe im just overthinking

[thin stratus]

Yes, it would correct them all. This is where Reconciliation comes in.

The Character Movement component basically does this too

The Client saves locally in an Array what stuff they did, with a Timestamp to it

The Server gets told what Timestamp this was executed on

And then sending a correction for just that timestamp

The Client then discards everything that is older from the array, + the entry that got corrected, applies the correction and replays the newer entries in the same frame

But in all honesty, that is most or less too much for UI

At least imo

[twin juniper]

i have to implement all that timestamp stuff myself?

[thin stratus]

Yeah this is what I meant when I talked about "boilerplate code" in an earlier conversation with Jambax

You can maybe "take" the Timestamp from the CMC ha

It's also generally a good idea to implement a better net clock (there are pins for that in this channel) to have an easier time with this

If you want the UI to be smoother, I would start with predicting and having everything corrected

If you really want to go the full way, it gets a bit of work

I don't see the need for reconciliation on UI Item Movements tbh

[twin juniper]

wow. Multiplayer is hard

[thin stratus]

Yes

[twin juniper]

i read some of their conversation, and Vaei github page, some part said that GAS is not always work
i should be ready for some heavy lifting myself i guess

[real ridge]

What are possibiliets of multiplayer game in unreal engine and what are the most common used in games I mean when game is going to be multiplayer you can make it via EOS or any other approaches?

[glad cloak]

Hey everyone, I'm new here so I'm not sure if this is the correct channel to be asking questions about replication, please let me know if I should go somewhere else.

I have a question regarding inventory replication, I'm making a spatial inventory system based of off Reid's 4 part series, but I need it to replicate and work in multiplayer. I have an issue currently where the server is correctly aware of the client's inventory, but the client constantly thinks it is empty. Is there something obvious I'm missing about replication here or is this not a replication issue? Let me know if you need more info.

[solar stirrup]

show code

what do you replicate for your inventory

[vagrant grail]

Is there a premade method for the nameplate on top of players to always face the camera of the local player ?

[solar stirrup]

screenspace widget component

should make it always face you

[vagrant grail]

Thx, but I have an issue, it scales depending on the distance, how to make it not do that ?

[rich crag]

I need help debouncing a constant overlap for server authorization checks... I have a ship with a helm that has a collision that checks for overlaps (proximity) before it adds a player to an array for authorization checks. The problem is, when the ship is moving fast enough, it registers many rapid overlap/ end overlap, and because of this, it never meets the qualifications for authorization (because server checks proximity again and does not get a positive overlap). I have attempted some debounce code, but it doesn't seem to work as expected.
can anyone tell me why, or a better way to debounce the overlap for the checks?

depending on timer length, i can get it to work about half the time but thats the best i get

[solar stirrup]

No idea, there seems to be a DesiredDrawSize property so maybe look into that

[vagrant grail]

does nothing in my case

[solar stirrup]

Did you enable bDrawAtDesiredSize