multiplayer

[chrome quest]

But it works

[pallid mesa]

hahaha, yes, but it's our bread and butter, gotta deal with it

Dave Ratti wanted to rewrite it for a long time

but that got on hold unfortunately

[limber gyro]

whos dave ratti?

[chrome quest]

Then he left🥲

[limber gyro]

and why did he leave?

[chrome quest]

The Epic games dev behind network prediction plugin.

[pallid mesa]

Dave Ratti was one of the main networking guys in Epic 😄

quite beloved around here, and he liked to approach the community from time to time

[chrome quest]

A new networking solution for the engine

He was quite helpful. Even had a few videos on his channel.

[limber gyro]

that wouldve been awesome tbh, i asked for some info on that in some UE4 stream and only got the silent treatment

imo its very very needed

[chrome quest]

Ah.. don't take it personally.

[limber gyro]

u cant have the best renderingengine in the industry and have a class that needs rewriting badly

[chrome quest]

It was the holy grail. With the new networked physics too.

[chrome quest]

Hmm.. the class doesn't really "need" rewriting.
The engine just needs a new networking solution

[limber gyro]

well it works fine, why do u think it needs a new networkign solution all together?

[chrome quest]

It's designed for small maps with low player count. And takes a lot of hackery to support a larger player count

[chrome quest]

Because the scope of the engine has evolved.

See above

[limber gyro]

oh ye, i heard they had to work quite a bit on it because of fortnite

[pallid mesa]

Fortnite says otherwise 😄

but yeah you can see the amount of engineering on top

[chrome quest]

True. But Fortnite has a lot of custom stuff

[limber gyro]

tbh i wish they had proper suport for MMO's or at least make the code base more manageable to the point where u dont need to write third party solutions

[pallid mesa]

rep graph, adaptative net update freq, push based networking, skipping things for replication, batched RPC's etc etc

[chrome quest]

Kill all dreams you have of making a mmo

Trust me

[limber gyro]

if i did it would be a hobby thing

i did manage to make a overwatch style shooter with matchmaker using playfab

[chrome quest]

You would spend a hundred years for that hobby to produce anything useful.

Although.....

Things may eventually change

With the way the engine is evolving

[pallid mesa]

whispers mass

[limber gyro]

well, if i did something liek a 100 to 200 player server

[chrome quest]

Mass

[limber gyro]

maybe it wouldnt be so hard haha

it would be a fun chalenge at least

[chrome quest]

You would need to modify the CMC extensively for this

[pallid mesa]

but yeah... mass is supposed to be used for specific problems

actors are there to stay

[chrome quest]

At the moment. 50 is the playable cap

[limber gyro]

without code changes?

[chrome quest]

Yeah

[chrome quest]

Actors are not so bad.

[pallid mesa]

you can make it run better clicking a pair of buttons

[limber gyro]

well, there was a guy in the forums a few years ago making a mmo dev kit for unreal

[pallid mesa]

ie: linear interpolation... etc

[limber gyro]

and he tested with like 150 players and he said it ran fine

[chrome quest]

Custom server I think

[limber gyro]

not sure what he did tbh

but the movement was quite simple

it was just ur regular walk around thing

[eternal canyon]

not rly sure about that

[limber gyro]

no flashy moves

[chrome quest]

Has anything changed?
I would love to know

[pallid mesa]

well im profiling recently and scalability is still not so great

no optimizations what so ever

just 50 cmc's in a blank level

[chrome quest]

Even that is still tasking. The CMC does a lot of calculations even for simple movement

You'd have to do some custom stuff. Like slowing tick rate for distant characters. Removing some redundant checks.

[pallid mesa]

it's, what you could call, playable... but the game time goes up quite a bit... considering you are supposed to have more things than just characters in a game

[limber gyro]

they could expose something like a distance culling var to the CMC, would probably help indies a lot

[chrome quest]

No function like that exists in the CMC. You have to use a manager object.
And iirc this is mainly for AI characters.

[eternal canyon]

umm

actors have that already

if ur talking about relevance

[chrome quest]

Do don't want to slow player movement. Since the server runs it's own calculations

[chrome quest]

Nah, not relevance.

[eternal canyon]

oh wait

ur saying ai

[chrome quest]

The server also simulates character movement and servers generally aren't the highest end computers so it's taxing on them.

[chrome quest]

Right

You'd need a manager actor for ai characters to slow their tick rate and other stuff when they're far from the player characters.

This way you can have 3x maybe 5x more characters in the world

If most of them are ai though

[pallid mesa]

It's not hard to steal this code from the LOD processor from Mass entities

[chrome quest]

Actually. I would love to explore this.

[pallid mesa]

take a look at #mass

pinned comments

[chrome quest]

Yeah. I've gone through the project. Awesome work you did. I hope to contribute also.

[pallid mesa]

open to it, now we are collecting community feedback for Mass for Mieszko

[magic yoke]

btw, verifying didn't fix it

I'm stumped why I can't use that struct as a variable type

[chrome quest]

And it's all bp?

[chrome quest]

Nice. I'll see what I can add.
Much of my suggestions would be from my time with bevy ecs though😅

[pallid mesa]

We are now taking a mini break, quite exhausted from life as of rn x'D

[chrome quest]

It's nice to get a good rest once in a while

[stone niche]

Hi, I wonder if anyone in this thread can help with a replicated move problem.
I am working on a fast paced FPS with a fairly robust movement system, heavily customised from the base UE code.
The reason, under high ping / high loss conditions, server corrections become excessive, and the limiting factor in resolving this, is the megre three moves that can be (re)sent per packet (New, Pending, Old).
I have done a lot of work on coding custom CharacterNetworkMoveData structures, FillNetworkMoveData and Serialization functions.
I can serialize and send an array of SavedMoves to cover +500ms ping and +10% packet loss. (next step will be to send only deltas to save space).
The issue, to de-serialize the data container at the server, I need to cast my custom structure to be able to replace the three moves with my array, but ServerMovePacked_ServerReceive is not virtual, so cannot be overridden, and the function that calls it, ACharacter::ServerMovePacked_Implementation, is also not virtual. Any ideas welcome?

[limber gyro]

This might be a silly question, but cant u just change the source to make them virtual?

sounds like ur working on a farily complicated project that would warrant engine source changes

would love to help further but im just getting started with the CMC myself

[stone niche]

It is a big project, a small team of us are updating a 20 year old game from the IDTech engine to UE, but so far we have managed everything without touching the engine directly, which makes keeping up with the latest engine releases easier, so for the sake of this one function, it is frustrating.

[limber gyro]

i know how u feel

I implemented my CMC custom movement thing but im still getting a bunch of net corrections?

any ideas what could be going wrong?

[stone niche]

Do you have a very long piece of paper, I have spent the last six months chasing down and fixing many causes of corrections, half of them issues with the UE code.
I used lots of "PrintDebugString" messages to track down issues and patch them one at a time.
The first thing you need to do is start identifying under what conditions they are better or worse, so when you run in editor with low ping and low loss simulation, do you still get lots of corrections.

[limber gyro]

im just using the editors default settings i assume

[stone niche]

If you have implemented any custom code that affects position or velocity, then that must be replicated to the server too, and past back in corrections, otherwise the Prediction system goes out of sync.

[limber gyro]

https://pastebin.pl/view/bdb081da

this is my code

i override calcVelocity

and just pass a bool to the CMC

some one told me that was my best bet on how to implement a dash

do i need to send back my velocity or something like that?

[stone niche]

There are a few ways, best thing is to follow a tutorial on youtube, it would be too much to type here. The problem is, once you get all that implemented, you still have to go in an fix the correction problems caused by the base engine code too 🤦‍♂️

[limber gyro]

well i followed a tut, but the tuts dont do things exactly how i did so i am a bit lost

how do i go about finding where the bug is?

what would be a good place to start?

[stone niche]

Disable your new function, do you still get corrections?

[limber gyro]

will test

gimme a sec

can confirm that corrections only occur when calling the dash

[stone niche]

under the Play dropdown, Advanced..

Turn OFF the Enable Emulation

Or, just set the latency and packet loss to zero.

The existing move replication only sends three moves at at time, so anything over a ping of 40 you will start to see corrections whenever anything gows a bit out of sync.

[limber gyro]

mine is turned off by default

i added the following line to the function "updateFromCompressedFlags" and now the dash doesnt work

bRequestDash = (Flags & FSavedMove_Character::FLAG_Custom_1) != 0;

[stone niche]

If you get corrections with that off, then the server is not executing the same code as the client, or is running the same code but in a different order.

[fathom aspen]

Prolly that event is running on client, that's why the value isn't being updated\replicated

[limber gyro]

i am assuming the same code is being executed because all the code is in the CMC and that exists in both the player machine and the server, so its probably the order then

im gonna print velocity to see if its the same in the server and in the client

LogNetPlayerMovement: Warning: *** Server: Error for Shadow_C_0 at Time=4.594 is 27.308 LocDiff(X=17.001 Y=21.370 Z=-0.001) ClientLoc(X=2925.690 Y=-960.900 Z=207.860) ServerLoc(X=2942.691 Y=-939.530 Z=207.859) Base: None Bone: None Accel(X=0.000 Y=0.000 Z=0.000) Velocity(X=-815.878 Y=-1025.886 Z=-555.644)

is this locDiff a variable that can be changed somehow?

[stone niche]

I had one issue when we implemented Limping, it was using something like GetWorldTime, to vary the walking speed, the problem was that the limp was executed part way through the code execution, so by the time it was executed on the server, it was the next tick time, I resolved that by using CurrentServerMoveTime instead, as that is syncronised, so if you use time for thinks like how long to dash, it needs to be suncronised time.

[limber gyro]

so i cant use deltaTime then

i cant find that variable inside "calcVelocity"

[stone niche]

Delta time is ok, that is the "Change in time" so should be ok.

This is the type of thing I use to debug, and sometimes use a screen recorder to then go back and read the output frame by frame if there is something complex or intermittent I want to capture.

if (GEngine)
{
    if (CharacterOwner->GetLocalRole() == ROLE_Authority)
    {
        GEngine->AddOnScreenDebugMessage(-1, 1.0f, FColor::Silver, FString::Printf(TEXT("Server: %f  %s"), GetWorld()->TimeSeconds, *Velocity.ToString()));
    }
    else
    {
        GEngine->AddOnScreenDebugMessage(-1, 1.0f, FColor::Cyan, FString::Printf(TEXT("Client: %f  %s"), GetWorld()->TimeSeconds, *Velocity.ToString()));    
    }
}

You can make messages specifically for values that you want to observe.

[limber gyro]

this line here, i am under the impression that i need to add it

[stone niche]

You can use Location rather than Velocity, or both, then see if the location changes when you press dash at different world times.

[limber gyro]

because the local CMC needs to update itself

correct?

[magic yoke]

is there a way to mark an exec chain to wait for server code to finish running?

Request tiles event > (Server) Request tiles > (Client) Update Tiles

[stone niche]

You should not have to ask something to wait if the code is running correctly, the same on both server and client.

[magic yoke]

I'm looking at options

I can definitely move my update tiles into a repnotify function

but I'm wondering if there's an option like that

tbh, putting it into repnotify is probably what I'm looking for thinking about it

I want something to happen client side when the server code is done running

[stone niche]

If it was very frequent, maybe set a bool and check on tick, but notify sounds best (im no expert though)

[magic yoke]

not exactly frequent no

making a 2d tile system

visuals client side

structs representing data side

but since it's tiles specifically, they're probably not changing a ton

it can probably be a bit inefficient in updating it because of the type of game I'm working on

thanks for being a sounding board :)\

[stone niche]

Although I see the code daily, it is a hobby project, and one of the other coders did the movement abilities so I dont have a working knowledge of the exact implementation.

[limber gyro]

thanks for the help anyways

i will keep looking at this to see if i have any ideas

[stone niche]

For info, I had to create a custom RPC to pass the bit packing call through my custom character class.

[halcyon totem]

I have imported an old map and it has about 4000 meshes, these meshes are mostly small. and make up the map. I imported them from cd4 with datasmith and it let me add simple collision to my meshes, since these are one sided meshes would it be a problem? it came from an old 20 year old game and I was thinking it shouldnt be a problem, but will it lag my game because there is so many?

[abstract aspen]

https://gyazo.com/3edc088a967b00fae1dbebec1c312a93 Mount seems to despawn after certain amount of distance in ue5 has anyone seen this before?

[fathom aspen]

This shouldn't be a ue5 issue, maybe because you are out of relevancy range for that mountain

Though mountains aren't usually actors, and then they are always relevant?

[limber gyro]

depends on ur gpu ofc, but it should lag on anything below a 3000 series because you will have way too many draw calls

also this is probably not the best place to post that question

[sleek flicker]

Just spent 2 days suffering cus I forgot auto posess was on from testing

[abstract aspen]

@fathom aspen the problem does not persist on same map with out world partician

[fathom aspen]

Oh yeah world partition. That has been introduced in ue5 and it could be it really, so idk :(

[halcyon totem]

@limber gyro sorry I thought this was mobile!

[twin juniper]

how can i replicate a function that generate a procedural level?

if i run that function on server then only the server can see the generated map

[chrome bay]

generated from a seed deterministically, replicate the seed. That's only half the problem though

You also need to generate the objects in the level with deterministic names from that seed

And mark them as net addressable

This can ofc only be done from C++

[timid breach]

Guys, did I understand correctly?

Even I spawned AI Controller on server, save it to the variable and replicate, this AI controller will be never replicated to the client?

[twin juniper]

really? no blueprint?

[chrome bay]

no chance

[twin juniper]

so i can't make a maze game multiplayer with blueprints

[chrome bay]

You can't do 90% of multiplayer in Blueprints

The problem you have is you need to spawn the procedural parts client-side, but they need to be net addressable and stably named which AFAIK you can't do in BP

[bitter oriole]

I mean, you don't have to make everything net addressable with deterministic names

You only need that if you want to be able to RPC references to those components

[chrome bay]

Or if you want to walk on them

Otherwise character movement will break

[bitter oriole]

Ah, shit

Didn't think of that

[chrome bay]

But ye just means none of that stuff will be usable for network at all, which could be a problem in other ways too

[twin juniper]

why the seed doesn't get replicated by the client?Am I doing it the wrong way?

[thin stratus]

Because the BeginPlay calls aren't timed with Replication

The Int just hasn't replicated yet

Use an OnRep for the Int Variable

[twin juniper]

okay

[limber gyro]

hey guys, i have been trying to implement a dash in the CMC and im still getting corrections, ive overriden the velocity first on the "calcVelocity" function and then on "OnMovementUpdated", they both generate corrections and im completly out of ideas on why the corrections are happening

maybe some one can take a look at my class and check what i am missing

https://pastebin.pl/view/e5a34340

because tbh i have absolutely no idea

[twin juniper]

what should i put inside OnRep_Seed function?

i tried like this but it is not working

[dark edge]

I mean can't you just spawn the stuff on server and let it replicate out? Depends on how much stuff you're doing but it's totally doable.

10x10 maze might be easy, but a 100x100 might be a bit much

[wary wyvern]

Has anyone used VOIPTalker component to make a voice chat?

I'm not able to make it work.. I've added to a player controller, registered a player state and sets voice attach component to a capsule, but it does not work in a package game..

[mild urchin]

hey eveeryone, i'm trying to multicast a niagara but it doesnt work for some reason wheareas it works for particules any idea why ?

[limber gyro]

what exactly do u mean by multicast a niagara?

are u trying to spawn an effect on all clients?

[mild urchin]

yes exactly

[limber gyro]

well it should work in theory

[mild urchin]

yeah ! it works for particles

just doesnt work on a dedicated server

[limber gyro]

what else are u doing with niagara?

[mild urchin]

just this

code is pretty basic

spawn emitter at location works perfectly

[limber gyro]

did u check which line is not being triggered?

are u properly passing that hit result from the client to the multicast?

[mild urchin]

not yet i gotta send a build to steam

i guess that yes because it works for the particle

at the right location and everything

[limber gyro]

im a bit confused here, ur saying its working with particles

niagara is used for particles

is not working with all particles?

[limber gyro]

what are u trying to spawn that is not spawning?

[mild urchin]

this works

this doesnt

[limber gyro]

ok so, is that line of code being hit at all?

[mild urchin]

i have to check this

on dedicated server

[limber gyro]

u can simulate on the editor

[mild urchin]

in editor everything works

the niagara is spawned

[limber gyro]

ur probably running the editor with the wrong option

u gotta run as client

[mild urchin]

yeah

thats what i do

it could be smthn eelse

i have added a pack from the markeeetplace

and marked for add eeveery file

[limber gyro]

is ur game gonna have a dedicated server or is one of your players going to be the server?

[mild urchin]

but sometimes it misses some

no we already have dedicated seervers

[limber gyro]

so why would u want to spawn particles on the server? why would that be a problem?

the server doesnt need to see particles

[mild urchin]

yeah

i dont want them to spawn on server

all clients

so multicast should work

so yeah i agreee

[limber gyro]

yes, so whats the issue?

[mild urchin]

shouldn't beee any different than eeditor

well the niagara doesnt show

when i play on dedicated seeerver

[limber gyro]

ok so when u connect to a server it doesnt show

[mild urchin]

i was not very clear sorry

yes

[limber gyro]

lets go back to the line trigger thing

check if its triggering that line

if its not u gotta check that PSC variable that u have

[mild urchin]

the problem is with bloodfx

but yeah i'm gonna check

gotta finish the build

[mild urchin]

okay so

everything works locally

my friend told me that the build to steam doesnt include niagara for some reason but doeesnt know much more

can't find anything on internet about it

[outer trail]

Hello. New to UE networking here. I've got a question about loading objects at runtime and then replicating them. Here's the scenario:

1. server loads an object (it's an asset, but has no hard references to it)
2. server assigns said object to a replicated hard reference property (i.e. UPROPERTY(Replicated) UObject* SomeProp)
3. client gets the reference replicated
4. ????

I've tried looking but found no answer - what happens on client? does it cause a blocking load of the asset? does it set the reference to null (thus causing a mismatch between server and client)?

[compact talon]

If I cast to the player controller on the gamemode and branch if the player controller is local, then true means its the servers controller as the gamemode only runs on the server right?

[deep geode]

Its stored in reference as a uobject. Its a very shallow class. If the encapsulating class is replicating them its replicated as well

Qhat do you want to achie from this?

[outer trail]

sorry, I don't understand what you meant

the "problem" in my case is that when replication happens, the asset is loaded on server but not on client

[twin juniper]

i don't understand how to spawn on server and replicate on clients, i watched tons of videos but i can't understand

[elder spindle]

does anyone know if there's a difference between playing your game in net mode client vs. as a client in net mode listen server?

i'm seeing some discrepancies

[pallid mesa]

yes

These are two different networking models:

• Play as Server: The server is a player, and recurring clients join to the server session.
• Play as Client: The server is headless, meaning that it has no controller, subsequent clients join to the server.

In the listen server model if the server pleyer quits playing, the session will be destroyed

the dedicated server is not a player so it is not supposed to play vfx or sfx or even animations

so there are lots of implications surrounding this concept @elder spindle

[deep geode]

What i meant was that the encapsulating class is set to replicate as well. If your uobject is stored inside an actor, the actor must be replicating as well. When an actor is replicating, uproperties that are replicated, are held as hard references depending on their class/type. Ie, asset is loaded the moment the encapsulating actor is relevant

[deep geode]

You spawn a replicated actor server side. What specific usecase are you trying to achieve

[elder spindle]

yeah this makes sense, but my question is: if you play in net mode listen server, if you specify more than 1 player. and if you do, then every other player will be connected to the listen server as a client. in that case is there (or is there supposed to be) any different between playing as one of those connected clients, vs simply playing in net mode client connect to a headless server?

[pallid mesa]

in listen server if you want 2 clients u need 3 viewports

got it?

cause one will be the server

[elder spindle]

yup i understand, but it doesnt really help sorry

[twin juniper]

i have a blueprint that generate a procedural maze and i'm trying to replicate it

[elder spindle]

im trying to understand why i see a difference when i play on net mode client vs. when i play as a client connected to a listen server (not as the listen server) on net mode listen server

[deep geode]

Yes, lyra devs made comments about how annoying listen server can be. Dedicated server is easily separated by has authority but listen server isnt quite so. Use case would be for UI/sound situations. If you were listen server and called play ui sound, speending on the impl, theres a chance that could get fowarded to clients as well

[limber gyro]

this should be just a variable

that u set to true

so u spawn it on the server and it will spawn on the clients aswell

[twin juniper]

like this?

[elder spindle]

yeah in my case the client on the listen server is working correctly, but the client on net mode client (dedicated server) is executing a server rpc for apparently no goddamn reason

[deep geode]

Yes. Before you spawn, do an autbority check, also the spawned actor ahould be set to replicate in cdo

[deep geode]

Better if you walk us through it

[limber gyro]

i have no idea whats inside that function

so i cant tell

[pallid mesa]

because the server instance has authority as its the server

[limber gyro]

is ur BP room Generator replicated?

[twin juniper]

yeah sure

[pallid mesa]

so there will be differences based on where you execution your code @elder spindle

[limber gyro]

is it not showing in the client?

[twin juniper]

i just followed this tutorial https://www.youtube.com/watch?v=Q4aAGLBqnsc

[limber gyro]

u have to check the variables of that blueprint

[twin juniper]

it show only on the server

[limber gyro]

go inside the bp, on the right side check your variables

and search for "replicated"

see what u find

[twin juniper]

should i have to replicate all of them?

[limber gyro]

im not exatly sure about that

is ur BP spawning objects?

if so ur probably gonna need to replicate them all

[elder spindle]

yes but in both cases i'm playing as a client. does it matter what type of server im connected to? i dont have any checks for IsDedicated

[twin juniper]

i have two functions, generate maze just generate an array with the paths and spawn maze meshes spawn static mesh to fill out the paths

[pallid mesa]

Are you testing with 3 clients in listen server and 2 clients in dc server?

[limber gyro]

i dont remember if a "mesh" can be set to be replicated at all

[pallid mesa]

you can get an equivalent view of a dc server using 3 clients in a listen server setup and see actions between both clients

[limber gyro]

but if it can, when its set to replicated it should show up in the client

[deep geode]

Interesting ly enough if the seed generates the same exact mesh you dont even have to replicate it. Just multicast it

Exact maze*

[twin juniper]

its not the same :c

oh wait

on the clients if i use multicast then its the same maze

on the server its completely different

[deep geode]

Then the tut you used is broken. Seed is supposed to make the same exact randomness, if it uses the same seed with the same exact parameters the maze should always be the same

[elder spindle]

lol i discovered an unrelated bug, but i get the same issue

[twin juniper]

actually its different because seed variable is not replicate properly

is it wrong?

[deep geode]

You dont replicate the seed. You pass it inside the multicast parameters

[pallid mesa]

correct so you get me... if you want 2 clients, you gotta test with 3 clients in listen server

[pallid mesa]

NO

YOU REPLICATE THE SEED.

[twin juniper]

...

[pallid mesa]

You absolutely replicate the seed. Otherwise late joiners will never get the state change

[twin juniper]

and how do i replicate it

[deep geode]

Mb mb, yeah keep the repnotify

[twin juniper]

so its not wrong?

[pallid mesa]

like that Michele like what you did.

[twin juniper]

then why its different

[deep geode]

Whats inside the rep notify?

[twin juniper]

nothing

[pallid mesa]

how are you calling that function?

[deep geode]

What replication conditions are on seed?

[elder spindle]

sorry if im being confusing, but again this isn't my issue

[twin juniper]

none

[deep geode]

Ao you have a race condition

[elder spindle]

it seems like clients in net mode client are executing a server rpc, while clients in net mode listen server are working correctly (not executing the server rpc)

[deep geode]

You spawn the maze inside the repnotify

[pallid mesa]

that code is wrong, I encourage you to go to the basics

begin play executes in both server and client

so you are server rpc-ing in server, which doesn't make sense

and which class is this?

[pallid mesa]

which is your issue

[twin juniper]

wow now its the same maze even if the seed variable is different from client/server

[pallid mesa]

you say there are inconsistencies, ofc there are I'm telling you the why

now, what is your issue

[pallid mesa]

read above, this code is wrong

[twin juniper]

it is the blueprint where i generate the maze

[pallid mesa]

so a random actor not owner by anyone

[twin juniper]

exactly

[pallid mesa]

you are not supposed to server rpc there

[twin juniper]

where should i put it?

[pallid mesa]

because it's not owned by a controller

[deep geode]

The print string still has the race condition issue. But the maze is fixed when tou spanw inside the repnotify. Try printing the seed inside rep notify

[pallid mesa]

you don't need a server RPC

because the begin play will execute only in server here

I'm going to setup a simple experiment for you to see the equivalences @twin juniper

[pallid mesa]

you'll have to be more specific, show code and such

[twin juniper]

thank you so much!!

[pallid mesa]

also Michele, I strooooongly encourage you to re-read the cedrix exi compendium if you didn't yet

and if you did, re-read it, there are some core concepts here that still need to be clarified

[twin juniper]

im going to do that, ty

[pallid mesa]

@twin juniper mind jump vc?

[glossy kettle]

rep graph is too slow for prod right

[pallid mesa]

depending your use case

if you have co-op game with a low quantity of replicated actors, not for you

now... if you surpass the barrier of a little game probably looking at it as a good idea

it distresses the server charge by linearizing the culling in one single place

also useful to define "replication gates"

[twin juniper]

i can try but my english is not that good >//<

[pallid mesa]

I'm spanish, don't worry @twin juniper x'D

ole ole paella flamenco

[twin juniper]

nice im from italy xd

[pallid mesa]

right I'm waiting you now in the vc feedback and support

[elder spindle]

im under nda so i cant get too specific. basically, we have a server rpc function and implementation for looking at interactable objects in the player character cpp (CheckInteractObject, CheckInteractObject_Implementation). CheckInteractObject is called on a timer at 10 times/sec. CheckInteractObejct_Implementation draws the line trace and sets a replicated variable based on the results. thats about it

[deep geode]

Are you calling rpcs on a timer? Thats expensive. Do the check when you actually interact

[elder spindle]

its not my implementation, but how else would you know what to interact with?

[limber gyro]

does any 1 know how to check if i am sending all the necessary information to the CMC for a custom movement?

[elder spindle]

its basically a "what am i looking at right now" function

[deep geode]

Do the line trace locally. When you need to interact, only do the rpc then

[compact talon]

When players join my lobby gamemode they give their default player information (username, cosmetics) to the host. The host then stores this. When the player changes cosmetics in game it tells the host it has changed and the host updates the array storing it and replicates the changes to all players on the server.

My issue is my game changes levels and the only thing to persist through levels is the game instance.

So I can store all server information on the hosts game instance, and when the level starts pull the information from the game instance. The issue is, when the players all connect and are given their controller and characters I need to tell them their information from the host (like their cosmetics etc).

I don't know how to tell the right players what their name and cosmetics should be. I was thinking of checking if their steam (using steam subsystem with advanced sessions) names match up but that allows them to change name and break my system.

Any advice?

[deep geode]

Seamless travel can persist certain actors, you can store it in one then persist when traveling. Youcan the. Store it as a map with keys as their user id and values as cosmetic

[compact talon]

ah, very nice. tyvm

[elder spindle]

yeah this makes sense, though i know very little about network programming, i just started getting into it yesterday.

[pallid mesa]

welcome to it 😄

and yes what uPnP suggested is basically a client side action that derives in a server side action

and it's dangerous!

Because clients could be teleporting objects so they are at their reach so they can grab them

that's why when you rpc the request for grabbing the object you need to issue a validation phase

ie: checking how far your server character is from the server object

@elder spindle

[elder spindle]

yeah ive seen that is an option as well

i appreciate the advice, but do you guys have an idea about my original issue?

also, any idea why Only Owner See isnt working?

[deep geode]

What issue? listen server vs dedicated server thing?

[elder spindle]

yeah

[deep geode]

You could always try it out first on packaged debug game. Pie editor has its own can of worms so lets rule that one out first

For rpc. Listen server will trigger on all Server,Client, Multicast

Its basically a player thats a server

It sounds so simple but you have to approach it differently on a case to case basis.

[elder spindle]

ok how would i do this

do i have to do a debug game build in vs?

[deep geode]

You can package it then play as if you released them to testers. That is if you have a interface or ui setup to join matches already

[elder spindle]

we dont lol

there is some logic being run on begin play though

[deep geode]

We really cant help you if your nda is in the way. Its bullish if you cant even do your job because of it. Kinda paradoxical

Do tou you have any other analogy?

[elder spindle]

i mean i dont think some throwaway screenshot will be a big deal

[deep geode]

If im deving a game thats is open to listen servers, i 100% always test on 3 players with 1 as listen servers. With bad network emulation on top, if the game doesnt break then you did a very good job. Only thing left is to make sure the game is secure

[elder spindle]

top is client 1 on listen server, bottom client 2 on headless server (client 1 is the main viewport window but its the same)

im trying to figure out why i have a debug line in one and not the other

[deep geode]

Wdym headless server?

[elder spindle]

this

[deep geode]

So youre saying the line trace isnt being fired when playing from listen server? Can i see the rpc call all the way to the line trace?

[elder spindle]

when i play on a client connected to a listen server yes

this is in the player bp

oh hold on

thats all of it

i just noticed the check for GetNetMode() < NM_Client but again shouldn't that make them the same?

[deep geode]

Have you tried with a usual has authority check? I feel like netmode is stratified between dedicated and listen server

[compact talon]

using get game instance within the gamemode gets the game instance of the host exclusively right? As the gamemode only exists on the server?

[chrome quest]

Yep

[elder spindle]

ill try it

[elder spindle]

same result like this

installing editor symbols for debugging atm

[deep geode]

im actually at a loss. what i expect is that you shouldnt see any debug line at all. since if youre saying that those pictures are on clients, then they shouldnt see it since the trace is being done by the server. if you say one is on the main viewport. i suggest you select New Editor Window (Pie) inside the play options. I believe you have it mixed up since the main viewport inside the editor has always been the server if it was either dedicated or listen

[elder spindle]

i believe playing in net mode client the viewport is a client. there is no way to "play" a dedicated server (hence "headless")

in net mode client every viewport/window/client gives the same result. it has a line trace

[deep geode]

oh yeah sry mb, sleepy head isnt thinking straight. there still shouldnt be any debug trace, that much should be clear

[elder spindle]

in listen server mode only the viewport(listen server) has a line trace, and all client windows dont have it (desired)

[elder spindle]

no worries, you've been very helpful so far

[deep geode]

have you tried toggling 'Run Under One process' inside project settings?

Should be inside editor settings, not project settings; should rule out some editor side effects as well

[elder spindle]

that fixed it lol

so i imagine running under one process causes clients in dedicated mode to evaluate as servers for some goddamn reason

[deep geode]

sometimes it works, sometimes it makes a whole load of problems. I personally keep it on to keep it light, then if I have bugs I cant seem to figure, I just build and run outside editor. Good to know its fixed

[elder spindle]

i mean it feels like a bug for that to happen, and it doesn't really explain whats going on. cant build the game in debug config so cant check how the HasAuthority() check resolves but im guessing thats where the problem is. listen server works correctly so ill probably just stick with that

looks like running as standalone game works as well

probably does the same thing

[elder spindle]

thank you for the help

[elder spindle]

holy shit i found it

right under run under one process theres a "Show Server Debug Drawing by Default" flag

what a fucking adventure

[glossy kettle]

[elder spindle]

next question: "Only Owner See" doesnt seem to work on my widget component

[deep geode]

read that as well. went over my head that it was part of your problem hahaha. I believe that's new?

[elder spindle]

yeah idk its such a niche flag but ofc theres a flag for it

[fathom aspen]

It does return true right, but the reason isn't fully correct. For example, the GameState runs on both, and you can still get true there too, but that's right for server side game state. So the correct answer is: it returns true because the local authority is in control. Also controllers on GameMode are always server side, as GameMode is server only, so there's no point in checking that, if that is what you're doing!

[dark edge]

What do you think casting is?

[compact talon]

Basically getting it, so if I want to run events on my custom player BP I need to cast to it so I can get its events

[chrome bay]

A GameMode is not a PlayerController, so that cast will always fail

Cast basically means "give me this object, if it's what I think it is"

[dark edge]

No, a cast is a type check / conversion.
It's "I have an Animal, please cast it to Dog because I wanna do dog stuff with it"

You get the thing, then you cast it to the type you want IF NECESSARY, then you can get its variables.
Casting is not the getting

[compact talon]

I see, tyvm

[limber pebble]

Hi all, how would you go about telling the server and client a door is unlocked once a player with a key has unlocked it.

[dark edge]

The server does the telling but just have a replicated variable bIsLocked

[limber pebble]

That hasn't been working for us, any ideas why it may not replicate prooperly?

[dark edge]

Is the variable marked as replicated and are you setting it on the server?

[elder spindle]

anyone have an idea why "Only Owner See" isn't working

[limber gyro]

probably something silly that ur missing

like spawning stuff twice

[chrome bay]

Is a Player Controller the owner of the actor it's attached to?

[limber gyro]

at least thats my issue 90% of the time lol

[chrome bay]

It's not the owned of the widget, it's the owner of the actor which contains the component

The root of that ownership chain needs to be the player controller

[elder spindle]

yup it looks the like player bp doesn't return anything for its owner

[magic yoke]

I have an object that I create client side currently, and I want the server to "know about it" so I can reference 1 replicated variable inside. As far as I can tell, I can't replicate objects easily?

How do I do this? Multicast the original object creation from the server so everything gets a copy of it?

[limber pebble]

Are you or anyone currently in this chat able to help my programmer on the Feedback and Support voice chat? My programmer can better show our issue for anyone who knows multiplayer programming?

[dark edge]

I'm at work but first confirm that the variable is replicated and being set on the server, NOT set on the client

[limber pebble]

Confirmed server. Triple checked, double checked, server side for certain! lol

[dark edge]

And how do you know it's not replicating? Print string on tick of teh bool shows server and clients disagreeing?

[limber pebble]

Getting my programmer to fill you in on this thread

[south otter]

So I have did it a million ways, the print string shows bool only happening on server

I also had it showing client and server, with the same results

[dark edge]

So to confirm, server says Unlocked, clients say Locked

[south otter]

Basically, I can either let client and server open door with key individually, then if they shut the door, its locked for the other player, or I can set it to where server can open, and its open for everyone, but not vice versa

Client and server both say locked, sometimes only server says locked depending what im trying

[dark edge]

Server says if door is locked or not. Server is the truth.

Client unlocking door should involve a run on server event. Client never sets the bool itself

[south otter]

the server sets the bool

So i have a basic key channel system, player, key and door all have key channels, if key and door match, door is unlocked.

[dark edge]

Just show your setup. How you're setting the bool and how you're printing it or otherwise testing it.

[south otter]

I dont know how to tell the server the door is unlocked for all when any player opens it

ok, i have photos before any changes, just the original single player set up with the interacted replicated, and teh doors replicated

ill show those first

and obbiosuly, the door, key, and player and variables, replicated

i also, ahve a set up inside the player, but this was my first try in the door bp

[dark edge]

Is Target the interacting pawn?

[south otter]

third person character

so yea

[dark edge]

Nah bruh, don't do the flip flop stuff. Just set a bool

1. Clientside input
2. Run on Server Event
3. If(condition), set bool (replicated, repnotify probably)

OnRep_MyBool
Do stuff

IDK if your doors have 1 state variable or two (are unlocked and open seperate?)

[south otter]

so after key set bool, right?

this particular door is alwasy locked unless a key is used

[dark edge]

but does unlocking open it? Or just make it capable of being opened.

[south otter]

yes

the player with the key has to open it

so its not actaully unlocked

[deep geode]

how big is your world with the door? ideally 2 players?

[south otter]

2-4

and there are tons of doors

but its just a master door, or will be

[deep geode]

and am i right to suspect that there are many doors that wont be relevant to certain players?

[south otter]

they will be relevant to everyone at some point

and most relevant to the key finder

[deep geode]

but not always?

[limber pebble]

its a constant state

[deep geode]

because here's the thing. what if you opened the door. then another player joins the game. or has been in a very far area then recently went to the door

the door doesnt have a state that its opened.

[south otter]

wont happen, they join together

[winged badger]

you can't multicast stateful changes and expect it to work

[south otter]

and relevance distance if the whole map

[winged badger]

that is what replicated variables are for

[deep geode]

whole map would be analogous to a map of what game?

[limber pebble]

can any one of you join a voice chat so we can share screen and you can see?

tell us how you'd do it?

[magic yoke]

on your opening player controller > call event that is cast to server that updates the door's open/shut/locked value

and you repnotify the variable to cast that information back to the clients

notify letting you make a function out of it if you need to do any other changes

[deep geode]

repnotify could just set the transform to the finished rotation (closed or open)

[magic yoke]

overall, for anything visual repnotify is kinda mandatory far as I've seen

just because you can't set actor base variables (like location/mesh/material) to replicate

[deep geode]

for anything with 'state' that needs to be triggered upon relevance

[magic yoke]

repnotify > replicate

I think you could do everything repnotify and be fine

but everything replicate won't work a lot

[winged badger]

you multicast stuff like explosion sounds, for example, if player wasn't close enough to hear it, they don't need to hear it later either

fire and forget

[magic yoke]

fair, but you could have code that deals with that somehow

just replication though you can't fix everything

because it doesn't cause any function calls

[winged badger]

there are nuances to even opening doors via RepNotify

as the solution where non relevant player suddenly appears near bunch of open, previously non relevant doors and those doors start opening with creaking noises

is hardly production level code

equivalent to dead enemies getting up on their feet to play their death montage

[solar stirrup]

I keep a timestamp for doors

sec

[winged badger]

and synced network clock

[solar stirrup]

^

allows me to keep door movement in sync just via time

[pallid mesa]

synced network clock as an ntp clock or using the built in stuff? @solar stirrup

[magic yoke]

any thoughts on my earlier question about object replication? I mean specifically objects

[solar stirrup]

built in, honestly close enough that you don't care, add half rtt if you feel like it, helps get it a tad bit closer on bad connections

[south otter]

I just need to know how to tell the server to tell all clients to unlock the door for everyone once it has been opened by a player with a key

[magic yoke]

I have an object that I create client side currently, and I want the server to "know about it" so I can reference 1 replicated variable inside. As far as I can tell, I can't replicate objects easily?

How do I do this? Multicast the original object creation from the server so everything gets a copy of it?

[south otter]

door animations are working on both sides already

[pallid mesa]

i disagree but I agree at the same time? you know the feeling

[solar stirrup]

simple replicated bool

[winged badger]

void ARTS_PlayerController::RequestWorldTime_Internal()
{
    ServerRequestWorldTime(GetWorld()->GetTimeSeconds());
}

void ARTS_PlayerController::ServerRequestWorldTime_Implementation(float ClientTimestamp)
{
    const float Timestamp = GetWorld()->GetTimeSeconds();
    ClientUpdateWorldTime(ClientTimestamp, Timestamp);
}

void ARTS_PlayerController::ClientUpdateWorldTime_Implementation(float ClientTimestamp, float ServerTimestamp)
{
    const float RoundTripTime = GetWorld()->GetTimeSeconds() - ClientTimestamp;
    if (RoundTripTime < ShortestRoundTripTime)
    {
        ShortestRoundTripTime = RoundTripTime;
        ServerWorldTimeDelta = ServerTimestamp - ClientTimestamp - ShortestRoundTripTime / 2.f;
    }
}

float ARTS_PlayerController::GetServerWorldTimeDelta() const
{
    return ServerWorldTimeDelta;
}

float ARTS_PlayerController::GetServerWorldTime() const
{
    return GetWorld()->GetTimeSeconds() + ServerWorldTimeDelta;
}``` @pallid mesa

[south otter]

Thats what i did, still not working

well, the bool works, just not for everyone

[solar stirrup]

How good is that solution compared to built in

[south otter]

and its replicated,, and tried rep notify

[winged badger]

very

[pallid mesa]

much better

[magic yoke]

sounds to me like you're calling the replication from the wrong context

[solar stirrup]

Because I use built in + RTT / 2 for my elevators (timestamp based movement) and I get no issue whatsoever lel

[magic yoke]

what class changes the bool?

what is the context of the event

[solar stirrup]

I think the CMC handles discrepancies in movement fine when you're on an actor

Never had any rubberbanding on a moving platform

Doors? maybe

[winged badger]

as it re-runs every 10 sec, so calculates delta from lowest ping time

[pallid mesa]

cmc has an ntp clock algo built in lol

[solar stirrup]

huh, probs why then

[south otter]

Tried it on character, and from in door blue print

[magic yoke]

character is owned by the server

[pallid mesa]

zlo, mind if I steal your code???? 😏

[magic yoke]

you can't do client>server calls from character I thought

hold on, pawn is*

hm

[winged badger]

go ahead

[magic yoke]

if you do client>server in player controller

I can guarantee that will work

I forget who owns character off the top of my head

[pallid mesa]

I have engine changes for ntp around the net driver, but its annoying

[winged badger]

i also have static functions that wrap around those

[winged badger]

so i can just do USolsticeUtilitylibrary::GetServerWorldTime(this)

[south otter]

Can u get on voice so i can share my screen

[magic yoke]

@south otter looks to me like character should be a server owned object

if it's kinda quick ye

unreal hangout

[pallid mesa]

ah hehe that's nice and blueprintable

[elder spindle]

so im getting some weird results when i check the owner of the player character

not sure how to interpret this

this is for 2 clients. it looks like it prints for both characters on each client

but on both clients only one of the bps returns an owns, and its not even the same both times

[tiny jungle]

does anyone know of any resources that talk in detail about implementing rollback based peer to peer multiplayer in UE4/5?

[dark edge]

Do you mean listen server or true peer to peer?

[tiny jungle]

true peer to peer, I'd ideally like 2-6 players to connect without one being the sole authority on the game state, but if that's more trouble than it's worth and I could make it invisible to the players anyway I might not bother

[dark edge]

Yeah good luck, that's far beyond a tutorial. That's completely contrary to the Unreal(tm) networking model.

[solar stirrup]

That'd require an unholy amount of engine modifications

[tiny jungle]

I mean I don't expect anyone do have done the work for me

[dark edge]

Yeah that's gonna be one of those "if you have to ask" type problems, I sure wouldn't want to have to do it.

Now if you had some black box library that your game talked to and every machine thought it was running in standalone it might be doable, but you'd have to do all networking yourself and toss all the replication stuff really.

Although peer to peer and "listen server that trusts clients sorta" are effectively the same thing

[tiny jungle]

where does the difficulty come in specifically? like I think I must be misunderstanding the problem. because I only need a handful of deterministic entities predicted on the client side and I'm doing their physics by hand anyway

in my mind it's just, share everyone's inputs, keep the illusion of real time gameplay if they match, resimulate the timeline if they don't

[dark edge]

Unreal is client/server at its core. If you have to ask what the problem is, it's too big. But you could probably do it as listen server, lots of fighting games have done it I'd guess.

[tiny jungle]

yes, mk11 has excellent fighting game netcode

[dark edge]

The problem is there's no such thing as "send this to everyone else" for anyone besides the canonical server. There's no sense of a connection other than that of a client-host. True peer to peer would be a nightmare in Unreal.

It's like web vs Bittorrent.

[tiny jungle]

right, well a listen server that trusts the clients then

[dark edge]

I'm guessing for MK11 they have a dedicated server that acts as referee but yeah, that'd be much more doable.

[elder spindle]

anyone have an idea why my "Only Owner See" flag isn't working properly?

[tiny jungle]

it's the predictive simulation that's the important part anyway and 2 players is the most common use case

[dark edge]

So have you made the simulation up yet? Does it run in its own scene that can rewind and replay or are you doing the gameplay in the Unreal context with actors and such moving around?

[low helm]

If you just want simple client authoritative movement there are some set ups you can use with the smooth sync plug-in

[deep geode]

Is there a gdc talk or breakdown? It would be very interesting to see how they handle discrepancies in latency

[tiny jungle]

this is a project that's just design docs right now, I just wanted to make sure I wasn't missing something obvious, I'm more of a vfx person right now and was hoping to avoid beginner mistakes by asking. it's going to be a fighting game framework where every action an entity can take is in discrete time slices and where all the physics are stylized and deterministic. was planning to have rewind and replay functionality regardless of the networking but I haven't built the implementation yet

[tiny jungle]

https://www.youtube.com/watch?v=7jb0FOcImdg there is in fact! haven't watched it since it was new and I should again

[tiny jungle]

wasn't aware of that and will look at it, thank you!

[low helm]

Any attempts to establish peer to peer connections within unreal would require massive rewriting of the engines networking. If you have to ask how to do that, I think it’s safe to say there is no hope, unless you start down that long road with the intent to learn how to do all of it by yourself which could take years

Unless you are a wizard, you are stuck with server Client Connections, which means that you will never have real control over the ping of the players

[thin stratus]

Maybe your aren't the owner? Or the View target is something else?

I found out the hard way how this all works when I had a camera actor that was the view target instead of the controlled pawn

[solar stirrup]

Quick question - an actor with an update frequency of 0 will still process RPCs and spawn on clients right?

[low helm]

I believe so yes, it should be easy to test that yourself

[elder spindle]

yeah it's got to be one of those, cause it's basically checking if owner = view target

do you know how to check what the view target is?

[elder spindle]

when i check the owner for my player bps i get this

[fathom aspen]

CheckViewTarget

Or GetViewTarget(there are bunch of them)

[fresh chasm]

Hello, i'm about to create an inventory for a multiplayer game. I would like to have your thoughts before I start it!
So I was wondering, for chests, should I :
1- Simply replicate the content (array of id+quantity)
2- Send the content of the chest to the player that opens it?
There can be up to 20 players near a chest, and there can be a lot of chests (lets say up to 100)

I can already see cheat with 1- because a player can read the content of a chest without opening it

What would you choose in this scenario ? Or do you have another suggestion ?

[fathom aspen]

#multiplayer message

[fresh chasm]

Thanks i'll take a look

[plain spade]

Is there any way I can make a hosting system where you would create a server with a name, and other players would join you by entering the name of the server?

[kindred widget]

You just add a Name as data in your sessions, and have your UI filter out sessions based on the searched name.

[ionic arch]

Hey can anyone help with the UE5 Server. I've build a Server but after running it gives this error after some time

[young kestrel]

Hi everyone. I'm doing a networked project with lots of custom movements. I added a sprint, dash and WallRunning, however, I still need 5 (double jump, wall jump, climbing, sliding and swinging). more and my limit are the compressed flags. My C++ knowledge is okay, but I didn't find resources on expanding the flags.

I read here about that 4.26 changed how that works and allows to get around the limitations, but I didn't find example codes to look at.

Currently I'm using UE5, so you know.

Can somebody link me to some example code or explain it more in details? I already looked at Unreal Engines documentation, but I didn't see where to expand on those flags at all.

I'm confident in Blueprint and made those custom movements all in blueprints a year ago, but that project wasn't networked.

Thanks for your help.

[pallid mesa]

Hi friends

does the Net Insights provide data per second?

So far I could only obtain data per net event instance

and compute average per net event instance

but this doesn't give an insight on how data behaves over time

[chrome bay]

If not the network profiler does

[pallid mesa]

The old one, right

ayy I will have to record more traces

thank you james :)

[brazen briar]

Hey! I am using the default character movement. This is replicating very well, but I have noticed that in high speeds, the client starts to become choppy.

When I jump, I can clearly see choppiness in the movement. The server runs well without chopping.

Do you know of any parameters I could look at to fix this?

[regal solar]

hello, Does ***clientTravel *** keep previuos player transform after traveling into new game session?

[frosty remnant]

Is there an easy way to find whether an error in my error log triggered server-side or client-side?

It would save me a lot of effort debugging in general

[winged badger]

there is a max tolerance you can configure before the server corrections are applied

you can also see them with i think p.ShowNetCorrections or something similar in console

default tolerance is 3 UU iirc, which is okay for speeds of 500ish

(human at running pace)

[brazen briar]

Alright, Ill give that a look

[pallid mesa]

the net profiler provides Outgoing bandwidth

but i can't see ingoing bandwidth

anyone here tried to extend the net profiler to provide such info?

I can see it in insights but it isn't very insightful

[solar stirrup]

Is there an easy way to check if an actor can send Server RPCs locally?

[bitter oriole]

"Is it owned by a locally controlled player controller"

Pawn has IsLocallyControlled and PC has IsLocalPlayerController

Normally any RPC user will be owned by either

[pallid mesa]

non owned actors can send multicasts

and that's also a rpc 🙈

[bitter oriole]

Question is about "Server RPC"

"can I multicast" is just HasAuthority, anyway

[pallid mesa]

AH hahaha okay reading comprehension sorry

😂

and yes, + sending a server rpc will give out a warning when the thing is not owned

[fathom aspen]

I don't believe so. You would need to do that yourself, see APlayerState::CopyProperties for reference

[solar stirrup]

Yeah I'll just do that

was wondering if there was a more specific field set on stuff like a net connection

[elder spindle]

Hi guys so im trying to figure out why Only Owner See isn't working

can anyone point me to the implementation in the engine source?

[split zealot]

Hey all. I've been stuck on a networking issue for a while. I have a game that has set puzzles that use RepNotify functions to set how the puzzle is generated. It seemed to work in UE4 pretty well, but after moving to UE5 it only seems to work about 2/3 of the time. The other 1/3, the RepNotify literally just won't get called for clients, like it gets dropped. So this is obviously a major issue for the players, or late joiners.

I've seemingly tried all the different kinds of combinations in the replication settings menu, but the update just gets dropped for clients sometimes and won't get called. Even if the net priority is high

[magic yoke]

If I create an object with the same set of code both server/client side (in controller beginplay lets say)

do references to that object work between the client/server?

[latent heart]

If the object is replicated from the server to the client, yes.

[magic yoke]

objects can't be replicated

[latent heart]

If the object is created by you on the client then no.

[magic yoke]

I mean the object class specifically

[latent heart]

Yes the can.

[magic yoke]

how...

I've looked everywhere :D

[latent heart]

Good question.

😄

[magic yoke]

if you try to replicate references to them, you get dummy pointers to objects that don't exist

[latent heart]

If it's an object on an actor, just make it an actor component?

[magic yoke]

nope

this is an object class

[latent heart]

You want to replicate the object class?

[magic yoke]

I'm not attaching it to actors

[latent heart]

Everything has to be attached to an actor to replicate, somewhere...

[magic yoke]

well, you can make things replicate through the player controller or player state

and those replicate

[latent heart]

Those are both actors.

[magic yoke]

hm

there was a reason I didn't want actor component

I forget why

[latent heart]

So, yes, you can add actor components to them.

https://forums.unrealengine.com/t/c-uobject-replication/18296 also this

[magic yoke]

(fun fact once you refactor an object > something else in blueprints you can't turn it back into a generic object)

[latent heart]

Source control / backup!

[magic yoke]

mhm, I have backups but they're too old for that little change lol

source control is a massive pain for UE though...

I tried and failed to set it up so said screw it at least I can do something

[latent heart]

It's really not.

[magic yoke]

do enlighten me

the internet failed utterly

[latent heart]

I admit, perforce is shit. But you can use something else.

[magic yoke]

I couldn't get perforce set up

that was the issue

[latent heart]

That is, perforce is shit for a single person, it's an enterprise solution.

[magic yoke]

yeah for sure

the power of server for source control kinda nutty

for single person

[latent heart]

Use SVN or plastic SCM (I don't know much about plastic)

SVN is super simple really.

[magic yoke]

thing is though

I'm only using blueprints

no C++ at all

does SVN work for that?

the alternatives all seemed pretty bad for blueprints

[solar stirrup]

SVN is fine

[magic yoke]

alright thanks for advice I'll have to set that up this week

want to finish my first task, and it's too late to save that mistake lol

I really wish I could remember why I had trouble with actor component

[latent heart]

If you want to convert it back to an object instead of an actor component and it isn't too complex.

[magic yoke]

atm it's fairly simple

[latent heart]

You can make a new bp, re-create the variables and then just copy+paste the entire graph.

[magic yoke]

couple functions

mhm

[latent heart]

Have to recreate the functions too ofc

[magic yoke]

honestly though what I really need to do is test what you said about objects

for knowledge's sake

make sure I can get it working

[latent heart]

Don't bother trying to replicate objects from BP.

Just use actor components.

[magic yoke]

hm?

ok well

I wanna try first :D

cat, curiosity, y'know

[latent heart]

You literally can't without c++ I think.

[magic yoke]

mmm, that would make sense tbh

it's kinda what I thought

but then I realized I created my objects client side not server side

and replication dun like that

[glossy kettle]

its not tbh

[magic yoke]

lemme rephrase

perforce*

is a massive pain

[glossy kettle]

it is tbh

[magic yoke]

I spent a solid 3-4 hours and couldn't get it installed

let alone working lol

[glossy kettle]

roll ur own git repo

on a NAS or some shit

no need to fck bout with LFS then

[magic yoke]

honestly might as well

[latent heart]

Or use SVN

[magic yoke]

it's a solo project so I don't really need checkout/etc

I just need the ability to roll back

[glossy kettle]

if its solo i think git is more comfy

p4ssforce

[magic yoke]

I might try SVN to see

I know git absolutely hates blueprints

and due to reasons I gotta use em these days

:/

better for my carpal tunnel

[glossy kettle]

🫂

[magic yoke]

<3

[magic yoke]

indeed you can't

alright guess I'm going component

t minus 37 minutes until I found out why I couldn't use components

[latent heart]

Reasons.

The hardest thing of all to overcome.

[magic yoke]

https://tenor.com/view/aliens-history-history-channel-meme-gif-10744300

[elder spindle]

has anyone had any luck getting Only Owner See to work? seems not to do anything for me

[ember dagger]

Works fine for me

What do you mean by not work? As in everyone's can still see it? No one can see it?

[latent heart]

Or only the server can see it?

[elder spindle]

all the clients can see it

server cant but thats expected

[latent heart]

Are you spawning it on the client?

Or spawning it on the server (just the once) and letting it replicate.

It sounds like you're spawning unique instances on every client... actually on the client.

[elder spindle]

its a default component in the c++ class, it gets created in the class constructor

[glossy kettle]

how horrifying

[latent heart]

That doesn't matter if you're spawning the actor incorrectly.

[elder spindle]

im not sure what you mean by "spawning" in this case

[latent heart]

How do you spawn the actor that contains the component?

[elder spindle]

actually i seem to have found the problem

apparently screen space widget components dont respect the Only Owner See flag

[latent heart]

This might be one of the few places where spawning it locally is the correct option then. 😛

[elder spindle]

so now the question is how to work around this

yeah sounds like it

how could i do that?

[latent heart]

BeginPlay -> check for authority -> add widget component

Something like that

[young kestrel]

Is there a way to use more than the 4 custom movement flags? I'm trying to get multiple movement modes replicated, but I reached the limit already and still need a few more flags.

I heard something about using enums but not sure how to set that up.

[elder spindle]

do i need to change the constructor at all?

can i move that logic into begin play?

[latent heart]

Go for it.

Just remmeber to remove the default component, you don't need it and it'll probably actually just get in the way.

[elder spindle]

yeah in this case i might just do it in blueprint cause i dont have the component by default anymore and i need to reference a widget on the file system

[latent heart]

You can add a widget component variable and assign somethign to it on begin play.

[elder spindle]

yup thats how ill do it

how do you create a component variable in c++?

[latent heart]

UWidgetComponent* WidgetComponent```

If you want to assign it with blueprints, Add BlueprintReadWrite to the UPROPERTY

[elder spindle]

oh i see what you mean by the default component thing

[elder spindle]

same issue lol

[latent heart]

Then you're not checking for authority.

[elder spindle]

nope it works correctly when the widget is rendered in world space. i found a 7 year old thread on it apparently its an engine issue

https://forums.unrealengine.com/t/4-7-3-3d-widgets-not-respecting-only-owner-see-in-ui-space-screen-mode/311768/13

[winged badger]

that would probably be because their owner is by default GameInstance

[latent heart]

If you create them on a client... actually on the client, not the server, then other clients can't possibly see them.

You also need to make sure that the created component isn't replicated.

[winged badger]

if you were to instantiate the widget manually, then set it as a UserWidgetObject on the WidgetComponent, it should work just fine

but yeah, if IsLocallyControlled() CreateWidget works better

[elder spindle]

in the header

authority check off begin play

only owner see is checked

each client can see the other's widget

component is not replicated

[winged badger]

if those ar echaracter blueprints

just put a branch with IsLocallyControlled check

and create the widget component only if true

and it will work just fine

from BeginPlay is also fine

[elder spindle]

this implementation crashes my editor any time i look at an interactable object.

im using an OnRep function to hide/unhide the widget

[winged badger]

if only the player needs to see his own

there is no need for any replication there

should be all handled locally

you just send a server RPC when you Start Interaction, server does some sanity checks that its possible, and runs the interaction code

[elder spindle]

again the widget itself is not replicating. its OnRep of a different variable

[winged badger]

no widget is ever replicating

and server doesn't need to know or validate if client should see an interaction prompt

interactable object should replicate its own state, from which client can figure our if it can be interacted with and just show the widget locally

[elder spindle]

ok ill try doing the hide/unhide locally

[winged badger]

you generally don't want to put yourself in a position where you need to constantly network sync several different objects together

and everything that can run locally, should run locally

our minimap and fog or war systems, for example, don't replicate anything at all

but they work just fine

[elder spindle]

im not the one who implemented the replication lol. i was actually recommended to use the OnRep function to hide/unhide by our lead programmer

but it looks like this works

[elder spindle]

thank you btw. i found a simpler work around atm but i've heard this from a couple people about this part of our replication set up and it definitely makes more sense to me than what we have right now. will require a more substantial rewrite

[magic yoke]

So I've been hit with a bit of a mind bender that I can't quite figure out

I'm trying to create an actor component that will spawn actors client side, but in dedicated servers doesn't spawn any actors to reduce load on the server

namely using it to contain code about handling how those batches of actors change when the server changes an array of structs inside it

so here's the weird thing

nothing at all is set to replicate

server side I spawn the actor component and attach it to the controller (I forgot an execution pin, I thought I'd have to create it both server/client side originally)

the component doesn't replicate, none of the variables replicate, none of the actors are set to replicate

only server side is this code running

but the actors spawned by the component on the server side version of the controller still appear client side

almost like "add component" is set to autoreplicate somehow on replicated actors like the controller?

I managed to blindly unit test my way into something that works moving my context detection into the begin play event of the component, meaning that it is actually replicating despite everything being set to not replicate

but why does it work that way

[short arrow]

Hey I'm asking this here because it is more the multiplayer part that I need know. I imagine that the reason Root motion isn't recommended on all animations is because it's moving your characters absolute location and rotation thus increasing the amount of network traffic, and clients would probably be misplacing the final location. However this shouldn't be the case if AI are running and playing root motion animations from the server right? Or am I totally wrong?

[solar stirrup]

If you spawn an actor on the server, it'll replicate

Assuming bReplicates on that actor is set to true

So it replicates it down to clients as well

[magic yoke]

well it's blueprints here

can I even see that property?

[solar stirrup]

Yep

Check your actor's defaults

[magic yoke]

"component replicates" = false

[solar stirrup]

I mean the actor you're spawning

[magic yoke]

I have an answer, but it's utterly uninformed so I'm not sure I should say it lol

[solar stirrup]

Doesn't matter if the component replicates or not

[short arrow]

shoot

[magic yoke]

the spawned actor also doesn't replicate

[solar stirrup]

Huh

[magic yoke]

hard setting movement makes lag super obvious since everything is teleporting, if a client falls behind there's lag smoothing that can be applied

[magic yoke]

I deleted something in an unrelated class and it stopped working, so I'm re-sorting my code. Possible it was using code from that other class that I thought wasn't used anymore

which is really strange that it would work at all given that

[solar stirrup]

Yeah if an actor isn't set to replicate it shouldn't spawn on clients

So either you're somehow manually spawning them on clients, or your actor actually does replicate

[magic yoke]

what I'm guessing happened

was the other class was spawning them client side

while the new class was only spawning them server side

so when I switched the server side code > client side

it got spawned x2 on the client side and the actors overlapped

so I didn't notice lol

I'm migrating code and I thought I'd finished migrating it all

guess I missed something

[magic yoke]

to kinda finish that thought: unreal has some inbuilt latency correction, but hard setting locations doesn't let it do anything

[short arrow]

yeah that's what I meant by clients would be misplacing the final location

which would cause teleporting and jitters to resync the location

[magic yoke]

what happens when you get that is "vibrations"

the client/server disagreeing on a location really looks bad

I was doing some super basic UI stuff in a test and just coded it that way because it wasn't the primary importance

and man oh man does it look bad lol

[young kestrel]

Is there any sample code for "FCharacterNetworkMoveData"? I have no clue how to use it. I read the documentation but didn't understand how I use that in combination with FSavedMove

I'm using UE5, btw.

[graceful flame]

They use it in shooter game.

Also this seems like it might be useful: https://nerivec.github.io/old-ue4-wiki/pages/authoritative-networked-character-movement.html

[plain spade]

How would I go about adding that data to a created session?

[pseudo merlin]

Is it possible for actors to spawn independenlly on client and server, but have a shared network guid and be replicated. Kind of like how I assume replicated actors that are placed in a level work? I ask because I'm working on an in game level editor, so some multiplayer levels wont be .umaps but will instead be actors I read from a .sav and spawn in game

I could just spawn on server and replicate them that way

but it might save bandwidth if players and servers can spawn their own actors and somehow sync the network uids after

[latent heart]

You're going to have to send them to every client anyway, so you're not really saving anything.

In the end, the data sent over the network is equivalent

Other than, I suppose, the data sent from the server back to the person who submitted the .sav

In the end it's probably less of a headache to just get the server to do it.

[low helm]

even for a somewhat large group of actors, we can presume that this logic will only run once at teh beginning of a game

so some added cost isn't important

in other words, you're overthinking it

and trying to make some weird backwards wraparound replication just sounds like a mess

[pseudo merlin]

ill be streaming levels in and out w/ this method

[low helm]

you could, however, have them be totally not replicated

[pseudo merlin]

but yeah I see the point that stuff will get sent anyways

[low helm]

it doesn't sound like you're streaming in and out

[pseudo merlin]

its zones in an open world kind of setting

but I think you are right to let UE4's default networking handle it

no need to overcomplicate

if it lags Ill solve it then

but not worry for now

[pseudo merlin]

Forgot to say thanks!

[sly kernel]

can someone please tell me how is this https://www.unrealengine.com/marketplace/en-US/product/fps-multiplayer-template different from Lyra for UE5 ?

[nova wasp]

Lyra is designed to be more modular

And uses the latest fancy epic backend stuff

It's also heavily GAS based and doesn't have any first person stuff out of the box

[kindred widget]

I don't remember how to do it specifically. If you're using advanced sessions, I know there was an array or something on them you could add new data to and pull it from. Depends on what you have access to.

[plain spade]

Oh sick, I was wondering if people still used that plugin

I'm on the right track then, thank you.

[young kestrel]

That doesn't seem to fix my issue. My issue is that I don't have any remaining slots for compressed flags anymore and "FCharacterNetworkMoveData" appears to make it possible. I have like 8 different custom movement types and with just 4 flags... I don't know.

[marble fox]

Why doesnt it go through the if (PC->IsLocalController())

[latent heart]

The immediate response would be - it's not a local controller?

[sly kernel]

So, that Marketplace asset is a better base project to build upon (for solo dev) ?

[lime ledge]

At the bottom of this page there is information about using and extending move data
https://docs.unrealengine.com/4.26/en-US/InteractiveExperiences/Networking/CharacterMovementComponent/

You can add your own flags to the custom move data you create, so you are not limited by the 4 flags that are spare in the compressed engine flags bitfield

[thorny saddle]

hey folks
what is No owning connection for actor issue for?

[chrome bay]

Means something doesn't own it, you're probably trying to call an RPC on something where it doesn't make sense

[young kestrel]

Thanks. It's pretty complicated, but I think I kind of understand how it works now 🙂

[graceful flame]

Also this one might be worth watching: https://www.youtube.com/watch?v=DoZyH86n_gs along with the code examples here: https://github.com/Pantong51/AdvancedMovementComponent and here https://github.com/HarryPearce/JetpackTutorial

[young kestrel]

Thanks! That's really helpful!

[gritty flume]

asking here instead, would somebody be able to point me to what is failing here? Im trying to spawn a vehicle for a selected building BP via a UI button:

its running fine on the first picture but it doesnt fire on the building BP (second picture)

[hoary spear]

I believe this is an rpc failing due to being called from a widget, which is client only ..

Also not sure the spawn would need to be multicasted if its spawned on the server (and replicates)

[glossy kettle]

spawn on authority not erry1

@ server

[gritty flume]

@hoary spear how do i make the widget call that event on the server then?

(i removed the multicast, thanks for that)

[hoary spear]

I believe you should go via the playercontroller , someone correct me if there's a better class

So widget -> pc -> rpc to server pc -> spawn units?

Havnt done this in ages so i might be wrong

[sinful tree]

Is BP_WarFactory a replicated actor that is owned by the player? Only then can you call a Client->Server RPC on it. Seeing as you're doing a Get all actors of Class, I'm guessing it may not be something the client owns if multiple players could theoretically be selecting it.
Otherwise, Squize is right, you probably would want to go through the local PlayerController to perform the RPC as you know for certain the player owns it.

[gritty flume]

so if its in the widget i can just get the playercontroller like this?

[solar stirrup]

Yep

[gritty flume]

this is my first try at replicated events from UI, so im quite unsure about certain stuff

thanks Erlite 🙂

[solar stirrup]

👌

[fathom aspen]

Would this return the PC even if the widget isn't owned by it?

I would think so

[dark edge]

It'll return the local playercontroller

[fathom aspen]

I see, regardless of whether it's owning or not

This could lead to potential bugs if he's not owning that widget then, and he's intending to do something player related with it. That's why I would just do GetOwningPlayer in that case

[dark edge]

Set up your networking through something (PC, Pawn, whatever) and just have your UI be a frontend to those calls.
Like say you were making a trade window. You'd make a RunOnServerEvent InitiateTrade in your pawn, and the UI would just call it. UI knows nothing of the network, just that it's talking to your pawn or PC

[solar stirrup]

It gets the local player controller

Which is always your own if you have a widget

[hollow python]

For each individual player, they are player index 0 on their client?

[dark edge]

ye.

[gritty flume]

ok, so i was able to pass it to the PC, but now it stops there

[fathom aspen]

Well what you want to do is call a server RPC instead

Like really why not just call a server RPC?

My answer was right. You are trying to call a client RPC from client

And that's a no no

[latent heart]

It'll work... just not as you expect 😄

[fathom aspen]

It's like calling a normal function I guess

[latent heart]

Yeah.

[latent heart]

Change this from replicated to owning client to replicated to server

And it should just work.

[fathom aspen]

I wonder if there would still be a slight overhead because it was intended to be an RPC

[gritty flume]

https://i.gyazo.com/88f8ca3429d575b3a2682755a16229ed.mp4 It works 😄 😄

https://i.gyazo.com/f1bcc4a8d9204620dd1800aae9acbbc3.mp4