multiplayer

[thin stratus]

Which are like Party Sessions

[shrewd tinsel]

thank you @empty axle and @thin stratus

[gusty slate]

By the way @thin stratus, are Beacons a solution to implement a Party system for matchmaking/etc in main menu like PUBG/Fortnite/Rocket League?

[thin stratus]

Yes

[shut gyro]

Specifically, Paragon used PartyBeacons to implement reservation systems so that people could queue into party sessions without joining them if they get full all of a sudden.

[gusty slate]

Thank you 👍

[gusty slate]

Is there a way to use the SpectatorMode and states and still be able to allow the player to attach/follow other Pawns?

a simple AttachActorToActor isn't working

[gloomy sedge]

If I have my Dedicated server exe running, and I play Standalone from the editor after editing something in BP, Should I still be able to connect to the server? or would I need to RePackage the game?

[fervent spoke]

does anyone know for a fact if NetConnection's AvgLag is roundtrip time

i would assume so but it could be half that

and i don't have a convenient way to test right now

[bitter oriole]

It's lag time

So half ping

[fervent spoke]

ah

[unkempt tiger]

Is there any function like OnConstructionPostNetSerialize that I can use to load and cache some data of mine?

[winged badger]

there be PostNetInit and PostNetReceive

[unkempt tiger]

thats some good stuff, thanks @winged badger ! Is there a PostNetReceive for structs?

[round star]

Can not for the life of me get the dedicated server to show up in th steam server browser

[winged badger]

its for actors

[twin star]

Anyone here happen to be good with networking and knowing how to calculate IP addresses?

[eternal parrot]

I thought VOIP requires sessions.

[thin stratus]

It needs some sort of connection. Sessions are just info.

[eternal parrot]

Is the default VOIPTalker going to work without sessions? I just want the players to be able to talk to each other on a dedicated server. I use steam subsystem, but not steam networking.

[silent valley]

@eternal parrot you must be in the same session for the built in VOIP to work I'm afraid.

You might be able to hack it with engine modifications.

[limber gyro]

having a bit of an issue with a client function

so i have a client function that spawns a niagara function, very simple

i call it inside a server function that is triggered on damage taken

my logic is that since that server is being called in the server then it would be correct to call a client one from the server

client function:

{
    UNiagaraFunctionLibrary::SpawnSystemAtLocation(GetWorld(), bloodParticles,GetActorLocation());

}```

heres the server function

{

    if(isDead==false && isInvunerable==false)
    {
        OnDamageTaken();
        SpawnBloodEffect();
....```

this is being called in the character class and i have confirmed with a break point that the SpawnBloodEffect function is being called

[winged badger]

blood effects don't need to be super accurate, usually

and also, client is notified it took damage

so why the separate RPC?

[limber gyro]

well, if i call the effect in the server it wont spawn in the client right?

[winged badger]

point it

blood effect is atomic to getting shot

if you have the fact of getting shot networked

you don't need separate networking for blood effects

[limber gyro]

i could call it on a change of HP but i am not sure if i want every hp change to be represented with blood loss

but still

isnt this suposed to be working?

[winged badger]

no idea

can't even tell if its a server or client function from above

[limber gyro]

but what do u mean, "the fact of getting shot"

first one is client, second is server

[winged badger]

that would only work on owning client

[limber gyro]

the take damage is only running on the server so the player doesnt know

[winged badger]

when it takes damage

but not when it inflicts damage

[limber gyro]

????

i am not following

where do you think i should put the function?

[winged badger]

ideally you'd simulate the entire thing

you somehow replicate shots

or the fact that you are shooting at very least

[limber gyro]

but when other players shoot it needs to be seen too

[winged badger]

so there are hits being made on clients, you just choose to inflict damage on server only, which is fine

but clients can calculate their own shots and spawn blood effects themselves

without waiting for server to tell them to

[limber gyro]

i am doing all that on the server tho

i spawn all the bullets on the server

[winged badger]

that makes the whole thing feel a little bit unresponsive

but if bullets are replicated

[limber gyro]

so far that has not been the case

[winged badger]

they can resolve hits client side as well

and apply blood effects when they hit

[limber gyro]

yes but damage is not limited to bullets

[winged badger]

minor edge case where client would hit and server misses so client has extra spurt of blood

doesn't really matter in the grand scheme of things, health still stays in sync

[limber gyro]

theres stuff like poison which does dmg overtime

[winged badger]

which is also replicated

separately

and can trigger particle or w/e effects when it is, locally

no need to send an RPC for that either

smoke&mirrors

if i spawned bullet actors on server and replicate them

my game would die in less then 5 seconds

[limber gyro]

i am aware that i can check the HP for example to spawn the blood but it just feels sorta weird since it feels like i would lose control and it would be a bit "hackish"

[winged badger]

actually

[limber gyro]

well, my game has 6 players per server

[winged badger]

it would look better

[limber gyro]

so theres nothing to worry about

[winged badger]

server spawns the bullet

bullet is replicated, correct?

[limber gyro]

yes

[winged badger]

so

that bullet flies in generally the same direction at the same target on client and server, yes?

[limber gyro]

yes

[winged badger]

so if you were to let bullet collide with the target on client, what happens?

[limber gyro]

that is all fine and dandy but i dont deal damage only with bullets

that would work if the game was only based on bullets tho

[winged badger]

you also don't spawn blood effects from poison

[limber gyro]

why not

[winged badger]

and the bullet hit in production would look different

then any other blood effect

[limber gyro]

they serve as visual cues for whats happening to the enemy

i have a spinning chain around players to represent a root effect so i might just go with blood on everything

also theres AOE kind of spells that will do dmg and they will need the blood effect 100%

[winged badger]

but again, you have the explosion actor replicated for those

or something similar

that can do their own blood effects client side

[limber gyro]

true, but i would have to call it every time i code a new character

[winged badger]

thing is if you have a visual cue on client that it suffered damage, you probably replicated what caused it before that

[limber gyro]

i might just go with the HP change

[winged badger]

and you can absolutely overload the network with 6 palyers

[limber gyro]

feels kinda "meh" of a solution thp

tho''

i can?

please tell me more about that

i dont wanna get caught with my pants down

i am not replicating much stuff now

[winged badger]

we have 8 players, with 2000 interactable actors, 150 active AI and listen servers

[limber gyro]

well we have 6 players xD

period

[winged badger]

we had to do some heavy optimizations

for that to work

[limber gyro]

what are you working on if i may ask

[winged badger]

because of the sheer number of actors

The Red Solstice II

it has a steam page

[limber gyro]

how far from realease are you guys?

[winged badger]

less then 6 months

[limber gyro]

how big is the team?

[winged badger]

12ish + few people on the side when needed

[limber gyro]

i assume the first one sold well

for you to be making the second

[winged badger]

golden rule is, never replicate anything you can infer on client from the data you already replicated

especially via RPCs

[limber gyro]

i will keep that in mind

[winged badger]

bandwidth is the 3rd most likely chokepoint on the network

[limber gyro]

its my first dance with multiplayer so...

i take all the help i can get

[winged badger]

after overflowing the RPC buffer and having too many Actors considered for replication

[limber gyro]

RPC's have a buffer, i didnt know that

thats good ot know

[winged badger]

everyone obsesses about bandwidth

and that part of the networking is actually difficult to fuck up

[limber gyro]

i rly should read the docs, but i get bored easily haha

[kindred widget]

I assume that's why the GAS uses stuff like the RPC pooling. Saw Kaos talking about that the other day. I will look at that system someday. Maybe.

[steel vault]

@winged badger game looks amazing btw.. great work

[winged badger]

@heady beacon is responsible for most of the fancy kabooms you see there

[steel vault]

Team is clearly incredibly talented. The VFX scream AAA.

[distant talon]

how do you approach rpc buffer problems (diagnosing, knowing you even have one, etc)? I feel like this is information that should be documented somewhere

[twin juniper]

is there a difference items are placed on a map opposed to when an item is spawned on the server?

[fossil spoke]

@distant talon You can use Unreal Networking Insights to profile your network usage during Editor sessions.

[distant talon]

we've had problems in the past that were solved just by going through and optimizing rpc call counts using the network profiler. I dont think there was anything that (at least recognizably) jumped out as "rpc buffer problem" though, is there a tell?

[fossil spoke]

Well you should be seeing high send rates of lots of data if its being overflowed.

Make sure your not calling Reliable RPCs on Tick or something silly like that.

Avoid Multicasts as well.

Multicasts tend to end up flooding the buffer if not utilized correctly.

Since they have a maximum limit per connection i think.

Thats quite low.

[gloomy sedge]

Hi, I've been struggling with dedicated servers for a couple days now, I posted a question in here earlier about opening level with the ip and someone said, I forget their name mentioned that i do not need to use this as the Join session will open the level. This however is not working for me so was hoping for some insight on to how I would go about fixing this

Should this work in theory?

[sinful tree]

@gloomy sedge I believe you need to set the Result variable on the "On Success" path. As it stands, you're probably not getting anything set in the variable.

[gloomy sedge]

@sinful tree Like so?

[winged badger]

Datura is right

[sinful tree]

Yeah, the other thing is by setting it in a loop, you're getting the last result of the results array.

[winged badger]

the results pin becomes valid only OnSuccess

[gloomy sedge]

So I should just se the variable as a single result?

[winged badger]

when the top exec out pin fires

no sessions were found yet

its an async node, and top exec pin is synchonous

so the Results pin is as a result, empty

only when OnSuccess fires did it find the results you can use

i have no idea what you're hoping to accomplish with that foreach loop though

[sinful tree]

You may want to do some checking of data with those results... They contain more data, like how many players are present in the session etc....

Ignore that pic..

This one is right

This would only look at the first result back, but it's also checking if current players < max players.

[gloomy sedge]

Okay, Thank you very much you two. Great help!

So when calling JoinSession with the found result, Will is take the player from the MainMenu to the Server Level?

[winged badger]

that foreach loop

will keep setting result until you reach the last result

so it basically iterated the whole array to find the last element

[winged badger]

yeah, that looks saner

[gloomy sedge]

haha saner

So now this is looking better, should this transfer the player from the menu to the server map?

[sinful tree]

That looks better, but again, you may want some verification before trying to join the session... like...

This would iterate all the results, filter out all that are at max capacity or have a ping > 500, then loop through them until it successfully joins one

Probably getting ahead of what you're looking for... Which is just to at least connect using the join session thing, but yes, what you have should work now.

[gloomy sedge]

@sinful tree wow! Thank you very much, You are a very helpful

Is that 'GET' a ref or Copy version? or does it not matter at this point?

[sinful tree]

I usually use ref when possible myself.

Shouldn't matter specifically in this case.

[gloomy sedge]

@sinful tree You still available?

[sinful tree]

@gloomy sedge Yep

[gloomy sedge]

Are you able to answer a couple questions?

[sinful tree]

I can try. No master of all myself 😛

[gloomy sedge]

Okay, So i followed the Epic tutorial on how to create a dedicated server

I have the server up and running

On the correct level

I have packaged the game and run the .exe

I click Join and the get the print string Unable to Join any servers!

Meaning that the Join Session is Failing to join any of the servers found

However, when I use the console command 'Open 127.0.0.1' It connects

[sinful tree]

I'm not really familiar with the particular tutorial you're talking about and I haven't really messed with the default Online Subsystem...Going out on a limb, but my guess would be that attempting to join a session would be trying to connect to your own computer using your external IP address, which doesn't work too well from what I've seen. Do you have another computer you could try running the client on?

[halcyon totem]

how can I make my windows open up even when testing multiplayer?

right now they open one on top of the other and I have to manually set them

does anyone kknow

[gloomy sedge]

Unfortunate I do not have another computer to hand 😦

[sinful tree]

Even production games have this kind of problem - Conan Exiles as an example, trying to join a server that appears in the server listing that's provided in-game that's running on my own network would fail, but I could join it using a manual internal IP address without issue. Do you have a link to that tutorial?

[gloomy sedge]

Actually, might just nab my dads laptop

https://docs.unrealengine.com/en-US/InteractiveExperiences/Networking/HowTo/DedicatedServers/index.html

They use the simple Open Level to 127.0.0.1

[sinful tree]

Ok, I'm guessing your server is calling this node somewhere in its game mode or instance?

[gloomy sedge]

Nope, I didn't think I would need to as the server is being hosted through a sepereate Server.exe

Oh, I have just seen that I may need to Port forward

[round star]

Ugh

I can't get a dedicated to server to show up in steam server list >_<

[gloomy sedge]

@sinful tree I'm heading to bed now 3am.. 😦 Thanks for all your help. Very much appreciated

[sinful tree]

Sorry I couldn't be more help. Sleep well.

[somber glade]

My understanding of the "reliable" option on something like a multi-cast is that it would "try" to run it, but if the server is really busy or something, it could fail. Just working on some combat effects, one of which is the small explosion particle when a player dies. The apply damage is being run on the server, so when it applies damage to a unit, if the health is less than zero it should explode, which links to a multicast which spawns an explosion particle effect. Without reliable ticked, it never ran on the client, not even once. I tried it about 20 times in pie, and nothing. I ticked reliable and of course it shows up. I feel like a pie environment should be ideal for testing something like that. Shouldn't this be playing some, if not most, of the time?

[lime leaf]

@somber glade IMO if all in stat unit is showing green it should. IDK if it does though but that'd be what I'd expect

[somber glade]

Very strange. Everytime I think I'm starting to get a handle on this, it just acts even weirder.

[lime leaf]

I've used to tick reliable on everything, and grown fond of using "WasActorRecentlyRendered" node to cull everything not needed to be shown/triggered

[somber glade]

That's probably what I'll have to do.

Don't suppose you know any way to get both windows in PIE to produce sound at the same time do you?

I want to make sure the impact sounds are playing but sound only seems to play when a window is focused.

[lime leaf]

I've been playing around with that WARR thing for controlling ticks to make my colonists walk at 5fps when outside of view f.ex. but if you do multiplayer note that it runs on client server but if you set f.ex. tick interval, it sets it for the actor both on server and client :S So I tried timers instead, but it doesn't seem to work well enough.. I could have separate timer on client and server, and change the interval based on WARR but it seems timers are less reliable than ticks in my case anyway

https://answers.unrealengine.com/questions/86929/playing-audio-when-the-game-is-not-the-active-wind.html

[somber glade]

Nice thanks. that's helpful

Sadly it didn't seem to work even after a restart.

well..it sort of works.

it works if the focus isn't the other pop up window

if I select a window and then click on my browser for example it keeps playing a sound, but if i click on the other Editor window, the sound stops

[lime leaf]

"There's an editor setting for Allow Background Audio" all I found quick heere

only works in Editor

[somber glade]

Yeah I've got that checked already apparently. Ah well

I'll just test it in a built version I guess

I'm guess this probably works in built games and controls volume when you tab in and out of a game.

[ember needle]

all, i have an issue in multiplayer that i’ve been battling for many months now.

i really hope some kind soul can give me a push in the right direction:

https://answers.unrealengine.com/questions/958705/physic-issue-in-multiplayer.html

basically as soon as the client also sets physics disabled, the listening server moves the mesh to 0,0,0

if the client does not disable physics, no issue.

[thin stratus]

Could that be related to you not disabling the movement?

The CMC is not happy with Physics Simulations

[ember needle]

@thin stratus I have tried so many things since then... I actually do disable the movement, complete code when I enable is:

when I disable is:

the weird thing is that it really seems related to movement, since the server sends the mesh to 0,0,0 when the CLIENT calls "set all bodies..." to disable physics

if I do not disable physics ON CLIENT, then the server is ok

[meager fable]

Imagine this scenario, My client calls server spawn actor SomeActor Inside SomeActor I create an input binding, whose input will it trace for? Owner's? Everyone? No-one?

[thin stratus]

@ember needle Honestly, have thought about just spawning a dummy actor?

I don't know why that bug happens to you, but at this point it sounds like you could just spawn a Dummy Actor and give it that skeletal mesh and hide the character

[thin stratus]

What?

[kindred widget]

@meager fable Input is local. So per machine. If that actor has an input key bind, it would be able to be used by whatever PlayerController calls Enable Input on that actor.

[meager fable]

Thanks

[ember needle]

@thin stratus yes I can go this route, but then I have to replicate the pose. That said, I am able to reproduce the "bug" with the TPS UE4 project, if anyone would like to take a look.

[grizzled stirrup]

Any tips on lowering Steam sockets latency? I know it routes through Steam relay servers but one of the advertised features of the service is that it reduces ping yet it's going from an average of 10ms ping without steam sockets when testing with a friend in the same city to 100+ms ping. I wouldn't even mind if it's slightly higher ping but this is like it's routing from EU to US and back again to complete the connection. I'm not sure if I'm missing some kind of detect region functionality or something and it's automatically set to an overseas routing server

[royal sigil]

Hi guys! I'm creating a BP actor with RepNotify bool var. I change this var on server, actor itself has Replicating enabled, but OnRep_ function fires only on server world. Any ideas why?

[meager fable]

If I spawn an actor on the server, does its begin play only get called on the server?

[meager spade]

if its not replicated yes

if its replicated, then it will be called on server and all clients

[meager fable]

thanks

[meager spade]

@meager fable by all clients, i mean all clients it replicates too

like you may only have an actor that replicates to owning client

[royal sigil]

Always prints "Server" but never "Client".

[thin stratus]

is the Actor replicated?

[meager spade]

show me the property details

he did say actor is replicated

btw if client changed that property locally, then its likely that wont fire the onrep. going to need more details @royal sigil

[thin stratus]

Ah, I didn't see the first message

[royal sigil]

Yes, actor replicates

[meager spade]

and how are you setting it

the value

[ember osprey]

does UFloatingPawnMovement replicate out of the box like UCharacterMovementComponent ?

[meager spade]

no

[ember osprey]

f

[meager spade]

if you look at the new Network Prediction plugin

it has a replicated floating pawn

using the new Network Prediction

[ember osprey]

is it stable yet?

[meager spade]

stable yes, feature complete, probably not

but Dave Ratti mentioned on UDN that it is stable

[ember osprey]

because I'm using the flying template and none of its pawn movement is replicated. WTF?

[meager spade]

ofc not

it doesn't use CMC

look at network prediction extra, flying pawn

[ember osprey]

Whats the easiest way to get the movement in that template replicated?

[thin stratus]

The only other thing that is somewhat replicated is the ProjectileMovement one

[meager spade]

and try it out

[thin stratus]

Replicating the Movement is the easier part :D making it smooth is the other story

[ember osprey]

@thin stratus read your doc, good stuff.

[meager spade]

yeah, network prediction is going to replace a lot of the CMC

probably as a different class

to keep compatibility

[thin stratus]

Glad it helps

[ember osprey]

so should I try to convert my flying pawn to a character then?

[meager spade]

well, you can, but, CMC is kinda built more for characters

[thin stratus]

Characters can fly though, so that would help you :P

[meager spade]

that is true, though network prediction does have a replicated flying pawn, and i would rather use that 😄

probably a lot cheaper also

[ember osprey]

its a straight up aircraft, is there an aircraft character example somewhere?

[meager spade]

maybe somewhere on the interwebs

[bitter oriole]

There is, the flying pawn

It's just not multiplayer enabled

[meager spade]

honestly, go look at the network prediction extras flying pawn

it works, really well

[ember osprey]

@thin stratus don't know if you saw this before:

[bitter oriole]

He probably did

[ember osprey]

thats the problem

[meager spade]

that compendium needs a revision 😄

[bitter oriole]

@ember osprey Look into rollback/replay, prediction, and do your own multiplayer stack for that mvement

About a month of work

[meager spade]

or do what i said

[ember osprey]

c'mon

[bitter oriole]

One of the paid Udemy courses on UE4 goes through pretty much that

[meager spade]

look at network prediction plugin

it has all that already

[bitter oriole]

Or that

[thin stratus]

I actually have not, but I also don't follow this stuff a lot lately.

[thin stratus]

What was that from again?

Is that official Epic stuff?

[ember osprey]

udemy course

You're famous dude!

[thin stratus]

I know a few years ago that Jess had a presentation to introduce peeps to UE4 and the community and they mentioned me in it.
Was cool, cause I was randomly sitting in the audience. Not so cool that she pointed to me and everyone rotated.
I was just chilling ;_;

[thin stratus]

Sort of, I guess, still weird to me, even after all those years. Also don't have the time to actually interact that much with people.

[ember osprey]

Yeah you can't take two steps around the multiplayer world without someone mentioned the The UE4 Network Compendium 😂

[meager spade]

@ember osprey https://www.thegames.dev/snaps/4ep3nTUNAD.mp4

network prediction plugin flying pawn

[thin stratus]

Noice

[ember osprey]

did you just build this?

[meager spade]

its example

in the plugin

[ember osprey]

This: https://docs.unrealengine.com/en-US/API/Plugins/NetworkPrediction/index.html

[meager spade]

yh

but enable the plugins

then show engine content

[ember osprey]

where are you getting examples from?

[meager spade]

and you have this

[thin stratus]

Didn#t know it was that far already

Did they state anything on how long it takes to be more or less feature complete?

At least in terms of a "version 1.0.0"

[meager spade]

dave stated its a point where no more changes to the underlying code will happen

at a *

[ember osprey]

so boiling it down.....switch to character or use that plugin? Which is the best choice?

[thin stratus]

Which means, you can use the underlying code to do all sorts of things?

[meager spade]

yeah

[thin stratus]

And they will use the same code now to maybe fix that mess of a cmc?

[winged badger]

hah

[thin stratus]

@ember osprey If Character works for you, switch to that

[meager spade]

well that should have happened before the end of this year, but with the current world situation

[winged badger]

that will take some work to untangle

[meager spade]

probably next year mid or end 😄

[thin stratus]

Gotcha

[meager spade]

that's the info i saw on UDN anyway from Dave.

[ember osprey]

haven't tried either, but I'm trying to walk down the correct path.

[meager spade]

@ember osprey i would use the network prediction

for flying pawn

it seems a better choice than CMC for flying stuff

[ember osprey]

has anyone packaged/released with the network prediction plugin you know of?

[meager spade]

nope

[thin stratus]

Idk how easy it is to debug it and extend it. CMC is a mess, but atl east people fought with it in the past

[meager spade]

CMC is a royal PITA

[ember osprey]

[meager spade]

i still fight with it daily, that and the navigation system

[thin stratus]

But Flying should be a movement mode on the CMC

So it should be build in

[winged badger]

it also tightly coupled to both character and playercontroller

and has code tendrils in both those classes

which is awful

[meager spade]

yeah, not encapsulated in the slightest

you can't use CMC without using ACharacter

[winged badger]

and you need to override half of it if you want the autonomous proxy to be controlled by AIController

that was just... yuck

[ember osprey]

So with this plugin am I still gonna have to replicate everything in the pawn and then just have prediction with the plugin, or will that plugin basicallly make the replication handling as out of the box as using the CharacterMovementComponent?

[meager spade]

it will replicate the movement

no need for CMC

look at NetworkPredictionExtrasFlyingPawn.cpp

you will need to create your own version of that (as that has hardcoded input bindings, etc0

but its based on APawn

and is really easy, and its commented quite well

[ember osprey]

ok, thanks for the help!

[ember osprey]

enabled both plugins and nothing shows up in content browser:

yours:

[empty axle]

In the bottom right you need to check "Show plugin content"

[thin stratus]

#multiplayer message

[empty axle]

Yeah or engine content actually

[ember osprey]

thanks! got it

[pallid mesa]

oh nice, gotta use the heck out of it

[gloomy sedge]

If I have a dedicated server running on my PC following the guide on the UE docs site. Do I still need to 'Create Session'?

[pallid mesa]

kaos!! you should have told me before hahaha

[gloomy sedge]

I would presume no, But I keep getting 'Unable to join server'

[pallid mesa]

can I have the link to the guide you are following?

[gloomy sedge]

https://docs.unrealengine.com/en-US/InteractiveExperiences/Networking/HowTo/DedicatedServers/index.html

The guide only uses the Open Level node to localIP

And this is how I'm joining the Server

[pallid mesa]

Ah I see, the setup for the guide is a much simpler tutorial since it's joining the local server instance you created through open level

so it's a bit like cheating

if you do want this to work over the internet with an OSS you do need to take a look into sessions

[dark edge]

I can't find much on the upcoming Network Prediction plugin, anyone here got an elevator pitch for what it does?

[pallid mesa]

if you are a Blueprint consumer, I do recommend you using the AdvancedSessionsPlugin from mordentral, it's really narrow, and if you have any question, probably someone has already had it before in this forum thread https://forums.unrealengine.com/community/community-content-tools-and-tutorials/41043-advanced-sessions-plugin @gloomy sedge

[ember osprey]

@meager spade You called it:

[pallid mesa]

replicates movement w/ prediction

[ember osprey]

From the official Epic github

the plugin is supposed to replace UCharacterMovementComponent

Here is a break down of the plugin: https://www.youtube.com/watch?v=_rdt-v1nFlY

[dark edge]

Does it look like it's movement specific or a more general property prediction system?

[ember osprey]

dave ratti

[ember osprey]

The plan is to replace the current UCharacterMovementComponent

[meager fable]

are delays broken in multiplayer? My Replicated actors begin play gets called untill debug on the client and then stops, runs perfectly fine on the server

[pallid mesa]

delay/timers work fine in both server and client

[orchid pollen]

This doesn't seem to be replicated/working on remote clients, is there another way to determine otherwise if a character is on the floor or not?

[meager spade]

movement mode will be falling

otherwise will be walking

[orchid pollen]

yeah this seems to be the same result, the server and owning client only seem to know about this, remote clients dont appear to be aware of the current mode

[meager fable]

Server prints that magma burst is valid and client prints that it's invalid how come this happens?

[meager spade]

because your spawning a replicated actor

then running a multicast

RPC's can arrive before the replicated actor arrives

so welcome to networking and race conditions

[meager fable]

oh boy

[orchid pollen]

why don't you just spawn it on each client individually on the multicast?

[meager spade]

or let beginplay of the replicated actor handle it?

as that will be called on clients its replicated too

[meager fable]

yeah that's a good idea

thanks guys

[halcyon totem]

happy friday everyone, when working on a mutliplayer map with streaming levels are we suppose to keep the lights on their own level? when streaming out of levels lights bleed sometimes

[gusty slate]

Hello everyone, is there a way to use the SpectatorMode and states and still be able to allow the player to attach/follow other Pawns?
a simple AttachActorToActor isn't working

[tidal crown]

RE: https://answers.unrealengine.com/questions/659688/how-does-a-client-determine-when-playerstates-are.html Is there really no way to OnRep notify PlayerArray from AGameStateBase? What do people tend to do to fire events when a player joins/is observed on a client.

(think updating list of players in a lobby UI)

Seem odd that the engine doesn't provide OnRep_Notify for this

but I guess I can make a parallel synchronized array? Just seemed wasteful to me.

[dark edge]

@gusty slate what pawn do they have in spectator mode?

[gusty slate]

A pawn deriving from spectatorpawn

With an CMC

@tidal crown There is a function in GameMode called when a player connects and is assigned a controller, I think it's OnPostLogin

[dark edge]

@gusty slate the CMC is probably overriding movement, are they meant to ever move around on their own or just follow players?

[gusty slate]

I tried disabling the CMC before doing an attachment but it didn't work. Ideally I would offer both player follow and free roam, but Player follow is more important

[tidal crown]

Yes, but that doesn't tell the client when state is replicated to them for use in a widget for example, thats only server-side.

GameMode events aren't replicated to the client.

[gusty slate]

you can start your implementation from there

[short cliff]

Hi everyone;
Quick question; I have some cubes on my level. I want to set a cube selected on the dedicated server when I clicked on it. I tried to make an rpc call with the cube actor as a parameter but it came null on server. How can I achieve something like this? The cubes are replicated of course, and I'm calling a function marked as Server.
Thanks.

[kindred widget]

@short cliff What actor are you calling the ServerRPC in?

One major thing, make certain that you're ONLY spawning the actors on the server, or that they're loaded from the level and set to replicated. So that the client itself isn't spawning it without it being told to from the server. If that's the case, you should be able to pass it's pointer to the server. Should come up valid.

[round star]

Can someone help me out with getting a dedicated to server to show in the stem server list. I can't get it to work..server runs just fine..but wont show in list at all

[crystal umbra]

Wow delays are really bad to use Timelines/timers are always the way to go. Or so it seems

[fervent spoke]

does replication of actors (or movement components) extrapolate/predict positions or something? like say a client has 100ms lag and an actor begins to move. does the client see the actor 100ms behind where the server sees it or not? because i would expect it to yet i'm seeing results inconsistent with that expectation
sometimes the clientside actor is ahead of the serverside one
edit: haven't tested on a real network, just with net pktlag

[wise bridge]

Hello everyone, I have been stuck on a stupid thing for a long time, I try to set in place a leave game button, work perfectly well when the client leave, but when the host do I can't make client leave from a PClist done at their connection. Any ideas why?

[fervent spoke]

btw does net pktlag add a delay from server to client? or only client to server

i think that would explain the problem i just mentioned as well as another issue i ran into

[glad sedge]

dedicated multi builders - what source do you pull from to do a build for 4.26? release? master?

[sinful tree]

@wise bridge When doing "Get Game Instance" you're getting it only from the computer that is running the game. So when a client leaves, it'll work just fine, but when the host leaves, your loop goes through the list of PCs, but it's looking at the hosts' Game Instance.

What you need to do is have an event on the player controller that is called instead, and that event can then get the game instance and run your destroy session caller

[wise bridge]

Oh ok thanks, I had a feeling about that, I was starting to do the thing on the Game Instance on the PC before I realised it was stupid and asked my question here 😅

[winged badger]

@wise bridge unreal knows how to go to the default level when the host disconnects

so you can just wire destroy session on your main menu level beginplay

and do nothing else on clients

[dark edge]

Any prediction is beyond the basic replication. What you're seeing is a movement component with prediction built into it.

[wise bridge]

I gonna check that tomorrow, but I had some issues with this method

Ty

[vocal cargo]

hey, weird issue here. I can't set the visibility of a component even using a Multicast

it works on the local client but it's not replicated to other clients

[tidal crown]

why the fuck is the only way to do seamless travel in BP to use "execute command"?

that is...hacky as shit

[sly violet]

I need answers on this as well. My head is gutted

[winged badger]

if you think c++ does something drastically different

you'd be wrong

[tidal crown]

it feels very gross to do that

[sly violet]

@winged badger Oh no...

[tidal crown]

like fuck it we're gonna use a text-based API ??

[winged badger]

yeah you can call ServerTravel

but comes to the same thing

[tidal crown]

call ServerTravel from where

in BP?

[winged badger]

c++

[sly violet]

Ok, follow up question. Should that server command live in Game instance, for any good reason?

[tidal crown]

oh

[winged badger]

would take entire minute to make a BPCallable wrapper

[tidal crown]

Yeah, I guess tho like there's C++ modules behind "servertravel" right? Why is this the only public API

[supple mural]

How do you guys fix rubberbanding?

I'm desyncing on my own local server, it's embarrassing!

[tidal crown]

what are you doing exactly?

That seems pretty hard to do.

are you doing a lot of stuff w/ server ticks? BPs?

[supple mural]

I'm just trying to walk, jump around in my map

Yeah my game is built entirely in blueprints

[tidal crown]

do you have a lot of timers/tick-based things happening?

that can cost you performance, especially in BP

[supple mural]

I have event timer delegates and stuff

[tidal crown]

a lot? are they really high frequency?

[supple mural]

I don't think I have many though

[tidal crown]

have you done any network profiling w/ the tool provided?

[supple mural]

The ones that fire, don't fire often and fire only on input and when it's done

I didn't know that existed

[tidal crown]

oh yeah check out the builtin network profiler

you can get a file that records network events and see if theres something weird

[supple mural]

Alrighty I'll look into it! Thanks a lot

Just curious, you think it'll be the same if I'll redo everything (everything reasonable anyways) in C++?

[tidal crown]

could be

BP is I've been told 8x slower than C++ but I bet its not likely the case for u

i have a BP based game and its not desyncing

i bet its something simpler

network profiling will tell you more for sure

[signal lance]

that's an understatement, depends on the use case but it can be much much slower than that

[real sky]

I had a question about Multiplayer when it comes to blueprints, is it possible to create a fully functional multiplayer game with just purely blueprints?(Including plugins)

[meager spade]

sure though you will hit limitations

do i recommend it? no 🙂

[winged badger]

i would not count on it being smooth with more then 4-8 or so players and very limited world size

[real sky]

How limited do you think the world will have to be?

[winged badger]

you literally have only 10% network functionality in BP

[real sky]

Gotcha

[meager spade]

plugins on the marketplace can kinda get past that though

[winged badger]

100-150 replicated Actors tops

[real sky]

Damn

[winged badger]

with 8 players

[real sky]

Would AdvancedSessions and other plugins people usually recommend solve some of the problems?

[winged badger]

they have nothing to do with in game networking

[real sky]

I see

[winged badger]

i honestly believe its less painful to learn c++ then network a game in BP

[real sky]

Time to throw a year of my life away lmao

[winged badger]

how long it takes depends on your existing skills

if you're already familiar with unreal API

it will be easier, as you don't need to learn API and c++ at the same time

if you have unreal-unrelated programming experience

that helps tons

[real sky]

I’ve been using BP for about almost two years and gotten the hang of things, will that help??

[winged badger]

yes, even more so if you learned good practices along the way, and don't do spagetti

c++ function names are same or similar as BP function names, generally

[real sky]

hmmm so transferring over wouldn’t be that hard

[winged badger]

and you know at least a part of what engine offers

if you're serious about making games, i would definitely recommend it

[real sky]

I see

Thank you for the advice

and honesty

[winged badger]

c++ can do so so much more then BP, and unreal is designed to work with combination of c++ and BP really

[real sky]

I see many videos from epic using BP for their multiplayer examples and it seems like it runs perfect without any C++

[winged badger]

we can spawn a 30k Actor procedural level and have it networked and ready to play for 8 players in a few seconds

[real sky]

Oh damn

that’s fast

wait procedural!?

[winged badger]

most of techniques we use are not available in blueprints

[real sky]

Def gonna think about swapping over

[winged badger]

we have 1200 interactable actors replicating using only 16 actor channels

which allows our server to cope with the sheer number of them

a lot of stuff, even basic stuff is just not exposed to blueprints

for example, you want to know when your Pawn is possessed on client, in BP

in c++ you can use OnRep_Controller

in BP you have to gimmick a Client RPC for it

which just uses extra network resources

and OnRep_Controller is part of the engine, so it will happen anyways

[real sky]

What if you created a small LAN project?? Would BP be able to run it just fine??

or I’m guessing C++ is the way to go for that

[winged badger]

small sure, but when im talking about creating a game, i am talking commercial

[real sky]

Ahhh i see

cause that’s what I want to create first

just something me and my friends could play

Obviously if i’m doing a commercial product I would need to learn the industry standard

[twin juniper]

Hey I'm working on continuous fire abilities for my combat system and I am thinking of ways to deal with packet loss. Should I use reliable RPC for the cancel action or is it better to have unreliable RPCs sending on an interval in terms of network usage?

[winged badger]

you'll still probably benefit from c++ just because of sheer amount of extra tools you get

@twin juniper how to handle something like that depends on so many things

[twin juniper]

I was hoping you wouldn't say that 😛

[winged badger]

my simulated proxies, for example, just know the character is firing

[meager spade]

what is a continuous fire ability?

[winged badger]

and have a fairly accurate idea whats it firing at

[meager spade]

weapon shooting?

[winged badger]

nothing else

[twin juniper]

yes like automatic weapon or channeled spell

[winged badger]

then they just guess on their own

[meager spade]

they are both different things

[twin juniper]

In my system I handle them both in a similar way

[winged badger]

you should definitely simulate, rather then replicate, everything you can get away with

[twin juniper]

I'm planning to have them execute a routine on a timer until a cancel action is received

[meager spade]

i RPC every bullet 😄

in my pet project

[twin juniper]

you do?!

that is important for accuracy I presume

[meager spade]

except minigun

[winged badger]

that brings the question what is accurate enough

game Kaos and i are working on for a living

is an 8 player co-op shooter with isometric camera

it doesn't generally matter if one shot ends up missing on client while it hits on server

[modern swift]

hi anyone know what cause pawn not spawn on remote client?

[winged badger]

as there are so many bullets flying around, you really can't tell

[hidden frost]

how do i get the create chat thing miunte 1.08 https://www.youtube.com/watch?v=8NtpIcbCrkw&list=PLXBIyoKwiri1NxwGouMS5w7ziCoT7Yx7b&index=10&ab_channel=AlenLoeb

[twin juniper]

My concern is that players will find that they have lost resources because actions kept executing due to a lost packet

[winged badger]

what type of game is it?

[twin juniper]

but perhaps I can do something similar to @meager spade and rpc a batch, and then if the next RPC is not received for the batch, it cancels the timer and does not execute

third person action/shooter

[winged badger]

Kaos uses GAS there

[twin juniper]

somewhat of a premium on accuracy but not CS GO important

[meager spade]

ya

[winged badger]

so he has built in prediction

he has hooks to roll stuff back if something goes to shit

[twin juniper]

I've made my own predictive system so I can handle that myself

I don't have experience in running a multiplayer game though so I am unsure what is the best mechanism over the network regarding unreliable and reliable RPCs

I would prefer a single RPC to cancel a continuous ability as the alternative may tick one or two extra times after the client chose to cancel

[meager spade]

GAS handles that nicely

[winged badger]

single RPC is fine, and that one should be reliable

also, timestamped

you don't want the variance in network latency causing it to cycle an extra time on one end

[twin juniper]

it will probably be one of the few reliable RPCs I use tbh

probably not the end of the world for bandwidth

@meager spade I did think about using GAS but decided against it in the end. A few things about it bothered me so I just rolled my own. It isn't as efficient no doubt but it works pretty nicely.

[winged badger]

bandwidth

is usually the least of one's problems

both the RPC buffer if you overdo it

and server's time evaluating actors for replication

are much harder to manage then bandwidth

[twin juniper]

the RPC buffer on the server for receiving RPCs from clients?

[winged badger]

for sending, receiving is easy

[twin juniper]

ah

So number of actors living on the server is the most important concern?

Hmm, I've just realised I don't really RPC from the server

So I suppose that isn't an issue for me so much as the number of replicating actors on the server

[winged badger]

few hundred is ok

more then that and you'll need to start to optimize

[twin juniper]

That is a plentiful budget for my game, I think I'll be okay

[meager spade]

fortnite has 50K replicated actors

on dedicated server ofc

Listen Server is a whole other ballgame

(as server and client logic has to be running the same time)

[twin juniper]

I'll be using dedicated servers if I can

[meager spade]

i wouldn't go dedicated on first game

[twin juniper]

that 50K is optimised a lot though, isn't it?

[meager spade]

the cost is immense

unless you have deep pockets/backers

or only expect 10 people to play 😄

[twin juniper]

it's a concern, but does the design change a lot if you wanted to design for listen server after having expected to design for a dedicated set-up?

[meager spade]

yeah

[twin juniper]

in what ways?

[meager spade]

well you normally gate stuff of with HasAuthority etc

or !HasAuthority

but then you need to check for things like IsLocallyControlled whilst being authority

for listen server

[twin juniper]

Hmm, couldn't you just run a server and a client on the same machine?

[meager spade]

that is not listen server

but sure

seperate dedicated server instance + client instance is fine

[ancient moth]

Hello ! I would need someone used to compiling dedicated server and client. It compile again the engine every times, even without any change on it... Need some help to understand why and fix it.

[twin juniper]

I think that is how I would do it since it would mean I can be lazy

people have beasty PCs these days anyway

[winged badger]

@ancient moth build a project, not a solution

[meager spade]

https://www.thegames.dev/snaps/AtSv3myxf9.png make sure you build just your project

[ancient moth]

I did it, it build the engine anyway.

[meager spade]

mine never rebuilds entire engine

[ancient moth]

I know... 3 months I try to understand why it do on mine :/

I saw thousand of forums where people have this problem, but no solution...

[meager spade]

you deleting things?

like intermediates folder?

you accidently changing engine code without knowing?

just a single space could trigger a big rebuild

[rich ridge]

As per my experience it only rebuilds that particular module not entire Engine.

[meager spade]

depends what file

though 😄

a core file, could cause a lot to compile

[rich ridge]

Yes because most of the modules do use core module

So it's a big chain

[halcyon totem]

I think I need a multiplayer expert I need to know why is unreal giving me errors for a line by trace for this reference ? I have a mesh on a character I use to interact with an elevator button it works but when in client mode it gives errors

https://cdn.discordapp.com/attachments/221798862938046464/787307168645906452/unknown.png

how else am I suppose to get a reference??

[ancient moth]

@meager spade I didn't delete any file and if I modified an engine code, I don't remember it... There is a way to reset all engine code to be sure it don't ?

[halcyon totem]

how is it possible im getting an access none from my player controller for a button press? is there some other way I need to access my player controller to use the is input keydown?

[ancient moth]

Also, when I do modification on the editor (blueprint) and try to build the dedicated server, it tell me the target is up-to-date and don't build anything...

It's like if it can't check if a file is modified

Maybe for this it rebuild the engine each time ?

[gloomy sedge]

@halcyon totem I would suggest you cast to your playerController class as well

[kindred widget]

Should always cast to pointers before using them. I'll end up saving you both computing and debugging time.

Well, check if they're valid more than cast. But in blueprint most people use that as validity checks.

[gloomy sedge]

Hi there, I have a rubber banding issue that I have discovered when joining a dedicated server. https://gyazo.com/a6e019c0c1580b276cc422cc7c31e0bf

The character's Movement Comp is Replicated

Using a very simple movement

[kindred widget]

@gloomy sedge You don't have to replicate the CMC. It does all of it's replication through the ACharacter class. Rubberbanding is usually due to lag between the server/client and the client predicting it's movement too far and the server correcting it, or the client and server having different movement speeds.

Yeah, your client also needs to set Movement Speed.

Oh, does. Missed that. Hmm.

I admit, I do this by just replicating a single bool of something like "SpringButtonDown" and have that RepNotify and let it change the speed on both.

[gloomy sedge]

I also check the Stats Net CVar and ping was around 15

Okay, I shall try the RepNotify and see if any changes

Using your way of replicating the single Bool still creates the rubber banding

[kindred widget]

@gloomy sedge What are your movement speeds? Are they something crazy?

[gloomy sedge]

150 walking, 300 sprinting

[kindred widget]

Hmm. Not likely that then. It only happens with the sprinting stuff?

[gloomy sedge]

it does also happen with the standard walking

[kindred widget]

Someone experienced in the difference between ListenServer and Dedicated is going to need to help then. :/ Cause simply setting the speeds to about the same, and making sure that the client isn't passing the distance setting thing with too fast of speeds is all that's really needed on a Listenserver. I can't see why that should change on a Dedicated server. 🤷‍♂️

[gloomy sedge]

yeah very confusing, unsure whether it is just my internet speeds everything being hosted on it or what. but can't even find anything online about rubber banding on dedicated servers

[limber gyro]

guys i have an actor that spawn and then does a raycast and dies, i use this for hitscan bullets

i also have a regular projectile actor

the both replicate

and when they apply damage the player is suposed to simulate phisics so that i can do physical hits

the issue is, while both actors are replicated the hitscan one doesnt work

since it is replicated i was under the impression that it should spawn in the client and do the raycast there aswell

maybe i am wrong?

[kindred widget]

@limber gyro You're likely killing it too fast. If you spawn something on server, and then set it for destruction before it even replicates, it won't get replicated to clients.

You'd be better off just doing the trace in the weapon and letting that persistent actor replicate whatever it needs to it's client version.

[limber gyro]

i have a destroy timer os 0.2f

of''

i will try making it bigger

[kindred widget]

Not sure then. Should work in theory if there's less than .2 seconds of lag.

But it's still a pretty brutal way to do that. Spawning is semi costly for something as simple as a line trace.

[limber gyro]

maybe i shouldve gone with a regular bullet with 999999 speed with CCD

ye doesnt work even with the bigger timer

[kindred widget]

The spawned actor is replicated and only spawned on the Server?

[limber gyro]

yes

[kindred widget]

That's odd. While maybe not a good idea, it should still be working.

Are you doing a lot of networking? If so, have you upped the 10,000 bit per second limit?

[limber gyro]

i dont think so

i havent even heard of that before

also ive had people from india play in us server while having less than 50ping so i am assuming my network is pretty light

the default scene root does not replicate tho

let me check that

still the same

[echo snow]

Is ping even related to that

[kindred widget]

Not really no. It's an engine hardcoded limit that the engine itself will enforce.

@limber gyro Add this to your project's DefaultEngine.ini

ConfiguredInternetSpeed=1000000
ConfiguredLanSpeed=1000000

[/Script/OnlineSubsystemUtils.IpNetDriver]
MaxClientRate=1000000
MaxInternetClientRate=1000000```

[limber gyro]

what does that do

[kindred widget]

That setting is a Megabit, you can lower it if you like.

[limber gyro]

but how is that relevant to the issue?

[kindred widget]

The default is 10,000. Basically it will not allow any data to be sent via replication or RPC if you have reached 10,000 in that second. So if you send 30,000 bits instantly for immediate replication, you're waiting for three seconds before ANYTHING else gets through, like actor replication.

It might not be, but you're having trouble having an actor replicate. It's a step to try.

[limber gyro]

i am 100% sure that is not the issue my friend, if that were the issue the regular projectiles woulndt be working too

[kindred widget]

Likely not, no.

[limber gyro]

im going to check it if it is indeed replicating by giving it a cube or something to see if it shows up

yep the cube shows up

could it be that the raycast is being made in the server and not in the client

??

maybe the server thinks that since it was already done in the server it doesnt need to be done again

[kindred widget]

Really depends on how you've set up the spawned actor?

[limber gyro]

wait i think ive found the issue

not sure tho

[kindred widget]

What event is the cast done on? How does it know to do it on the Client?

[limber gyro]

i am using a hasauthority

its spawns a raycast on the tick

because the begin play was too fast for stuff to work

[twin juniper]

Hi, I would appreciate any help. I need help understanding multiplayer pawn possession. At the moment I calculate one transform for each player controller in my game mode on 'event onpostlogin', then I cast to the each player controller and inside each player controller I do the following

but doesnt seem to work.

[limber gyro]

@twin juniper i think u have to specify the controller

let me check my code

[twin juniper]

This script is inside my player controller so 'self' is a player controller.... or do these PCs not exist on server or something?

[kindred widget]

@limber gyro But if you're using HasAuthority, won't that only run it on one or the other?

[limber gyro]

doing it on the else part

@twin juniper i think in theory u are correct, in practice i have followed a tut from an apic guy and he passed the controller

so i dunno

[kindred widget]

@twin juniper Normally GameMode handles Pawn Spawning, but that should work in theory. Is it not possessing?

[limber gyro]

i am doing it in the game mode aswell

if the PC spawns a character he will the owner no? so when u try to posses that wont there be any issue with you possesing something that the server doesnt won?

tbh i dont know

[kindred widget]

I'm pretty sure that the possession call also sets owner though.

[twin juniper]

I now set the script all to run in my game mode

[kindred widget]

Regardless, what is the issue? Is it not possessing, or is there just no input?

[twin juniper]

Here is what I use, I set number of players to 6 and 'hello' prints 6 times on server

The pawn is only spawned on server, none of the clients have pawns the controller controls

oh wait - I can see the other client pawns on server so I guess they are not replicated to client

[limber gyro]

LOL

[twin juniper]

so I need to replicate spawn actor somehow

[limber gyro]

go into the BP and make sure they are replicated

tick the replicates box

[kindred widget]

Pawn class should be replicated by default.

[twin juniper]

it is

[limber gyro]

ummmmm

so you can see the pawn spawning in the server, but it doesnt show up in the clients

?

and its replicated

[twin juniper]

maybe I need to multicast the spawn, but execute the possession just on server

Yeah dont see any pawns on client.

[limber gyro]

if you spawn something on the server and its replicated every one should be able to see it

try the same function in the game mode

see what happens

[kindred widget]

Spawn is replicated by default if the actor class is replicated.

[twin juniper]

I am spawning inside my game mode

[kindred widget]

How much other networking stuff are you doing at the moment?

[limber gyro]

i have no idea then

[kindred widget]

Cause you might have the same thing I just described to Sonic even though that wasn't his issue.

[twin juniper]

I need to replicate the pawn movement, I had rotation working but movement was a problem, I thought a problem was the fact the pawns were not being possessed properly, so I removed default pawn class and started to spawn and possess the pawns manually (also will need that for later anyway, since I want variable pawn types depending on what the player picks)

Also my animations replicated fine

[kindred widget]

Animations don't replicate. You use replicated conditions to simulate similar states on clients.

[twin juniper]

Ah well maybe I misremembered, but I'll cross that bridge when I get to it

Game mode only exists on server right?

[kindred widget]

Correct.

That won't have any bearing on the spawning though. You can spawn replicated actors from any class anywhere on the server and they'll replicate to clients.

[twin juniper]

Here are the replication settings. The character I am spawning is a subclass of a more general character class (with the exact same replication settings)

and am I right that I have 'auto possess player' disabled in each character? since I am doing the possession manually.

[limber gyro]

@kindred widget i figured it out, turns out i was hitting myself in the client with the raycast

hehehe forgot to add an ignore actor

i have no idea how this didnt create any bigger issues before LOL

[kindred widget]

Oof. Done that one before.

@twin juniper It's extremely odd that you can see those on the server, but not on clients with them being replicated...

Like, you can consistently see them on the server, all the time, no issues there?

[twin juniper]

yes, whether or not I use dedicated server

[kindred widget]

Is it possible that you're doing a ton of other networking anywhere else? What else in the game is networked?

[twin juniper]

oh I think I could be spawning wrong

[winged badger]

take a breath, rapidly making guesses as to what went wrong is rarely the most effective approach

putting a breakpoint on event BeginPlay is a good start

[twin juniper]

I think Im using a foreachloop where I should be using foreachloop with break

[winged badger]

you should have 1 hit on server 1 hit on all clients for every replicated player pawn

[twin juniper]

yeah fixed

Now I have the problem I had yesterday, I am using 'addworldoffset' to move which I have managed to replicate but it is choppy. I would like to use 'addmovementinput' or 'addinputvector' but these do nothing

[winged badger]

those work out of the box unless you did something weird

[kindred widget]

@twin juniper AddMovementInput requires a MovementComponent. Such as FloatingPawnMovement.

[twin juniper]

Oh I know I have a movement component I have tried 100 ways, I also tried adding a vector to floating pawn movement

my pawn is of character class which has movement component by default no?

[ember needle]

I have a level which contains many stream levels, each one with their own PlayerStarts. I need to randomize their count & position, so that everytime it's a different map (though composed of instances of the stream levels).

What is my best option to do that? ATM I'm considering having the server randomize the stream level count & position and broadcasting a replicated variable from GameState. OnRep of this variable, an event is called that triggers a "create instance" loop for these stream levels on every client. However, I'm not clear on how then to spawn the players since the creation / location of PlayerStarts happen only after all of this has happened, and in general it happens in the GameMode.

So AFAIK I have the GameState run before the stream levels are loaded on the clients.

What would be a good way to achieve this?

[winged badger]

c++?

[ember needle]

@winged badger me?

[winged badger]

yes

[ember needle]

I'm in BP but can do C++ if needed. I'm trying to understand a proper course of actions

[kindred widget]

@twin juniper Characters do have the CharacterMovementComponent by default. And you just have to call AddMovementInput from the client.

[winged badger]

is seamless travel involved?

[ember needle]

yes

[winged badger]

so there are few key points here

[ember needle]

standard lobby etc as per @thin stratus lobby on the marketplace

[winged badger]

each PC when its player loads a level (note: this will be departing lobby PC, not game PC if its not the same class)

first calls NotifyWorldLoaded, then ServerNotifyWorldLoaded

when server finishes the seamless travel, it calls PostSeamlessTravel

[ember needle]

(not the same class PC lobby vs PC game FYI)

[twin juniper]

This is the BP I have in my character. (I recently added the switch has authority didn't make a difference). The disconnected node is what I had before which worked but replicates badly.

[winged badger]

in it, it iterates over all controllers that reported in, and calls HandleSeamlessTravelPlayer for each

this will be before any of your streaming levels are loaded

and that is very much not desirable for your setup

as that will start the players up with what player starts it has on persistent level

players that finish seamless travel after server have the HandleSeamlessTravelPlayer called on them as they call ServerNotifyWorldLoaded

what you need to do is prevent HandleSeamlessTravelPlayer to be called at all, for any player, before your streaming levels are setup

and run the iterating over all controllers thing that AGameMode::PostSeamlessTravel does after they are all ready

ontop of that you should not let GameMode start a match before all streaming levels are up and running and all players have finished travelling

[ember needle]

ouch

[kindred widget]

@twin juniper Don't use SwitchHasAuthority.

[winged badger]

you can hook up into AGameMode::StartPlay or AGameMode::InitGameState

preferably 2nd one

[kindred widget]

That'll only run if you're using a Listenserver and the Listenserver is using that Pawn

[winged badger]

to start your level loading

[twin juniper]

sure but makes no difference.

[kindred widget]

@twin juniper This is your character class?

[winged badger]

you have one convenient guarantee in all of this @ember needle - no Actor on the client will ever call BeginPlay before the GameState Actor has replicated

[twin juniper]

its in my more general character class of which the specific character I control is a subclass of

[ember needle]

I had no idea that GS MUST be loaded before any beginplay is called

[winged badger]

and yes you should definitely use your GameState to do any replication you need done before BeginPlay repated to level generation

its OnRep_MatchState

in GS

that tells client world to call BeginPlay on its Actors

[ember needle]

@winged badger i'm not sure I got all of that, but this is gold.

[winged badger]

you have very few guarantees with order of things in networking

so that one is awesome

ideally you'd get that running, then not start the match until all clients report via RPCs they finished loading streaming levels

[ember needle]

@winged badger i'm trying to understand all of this, bear with me

[winged badger]

thats an upgrade though

[kindred widget]

@twin juniper This is all you need for a character to move from input. Should work for walking or flying movements in the CMC.

[winged badger]

^

[ember needle]

@winged badger so:

• override PostSeamlessTravel so that it does not call HandleSeamlessTravelPlayer (hopefully there's a BP equivalent)
• Use GS from server to broadcast the list of stream levels and their position
• Clients create streaming levels based on this info, when they receive it (GS is replicated when BeginPlay of level BP is called)

what I'm not sure I got: "run the iterating over all controllers thing that AGameMode::PostSeamlessTravel does after they are all ready"

[winged badger]

look at the function in gamemode

you can just put a boolean in GM when all streaming levels load

and override HandleSeamlessTravelPlayer so it does if (!bFinishedLoadingStreamingLevels) { return; }

instead of overriding PostSeamlessTravel

[ember needle]

you mean https://github.com/EpicGames/UnrealEngine/blob/release/Engine/Source/Runtime/Engine/Private/GameMode.cpp#L770

[winged badger]

yes

but you have to execute that after your streaming levels are loaded

[ember needle]

so i can use PC to report back when levels are loaded in all players

[winged badger]

you get unintended bonus there

if you send an RPC each time client loads a streaming level instead of when it loads all of them

you get the data for the loading progress bars

[ember needle]

lol

IF i get this running then I'll get to that

...any idea if part of this can be achieved in BP?

[winged badger]

then you just transfer that data to their PlayerStates

and then it replicates, so each player can see everyones loading status

[ember needle]

gotcha

that part is easy

[winged badger]

gamemode stuff best do in c++

[ember needle]

the rest i'm still pretty much... digesting

[winged badger]

you can't really split PostSeamlessTravel in 2 functions in BP

[ember needle]

my C++ is extremely basic, i program in other languages (erlang mainly)

[winged badger]

what you need to do in c++ is fortunately pretty basic

[ember needle]

so let me rephrase

[winged badger]

void AGameMode::PostSeamlessTravel()
{
    if (GameSession)
    {
        GameSession->PostSeamlessTravel();
    }
}

and you need the rest of that code from it in a separate function you would call when all streaming levels load

and also return from HandleSeamlessTravelPlayer if the streaming levels haven't loaded yet

[limber gyro]

i have physical animation that happen when something overalps or hits the player but i only want the enemy players to see it, i dont want the player itself to run those animations, whats the correct "if" to use in this scenario?

[winged badger]

you can override ReadyToStartMatch in GameMode from BP

[ember needle]

instead of what

PostSeamlessTravel?

[winged badger]

?

[ember needle]

i meant this ^ what for

[winged badger]

so it doesn't start play (call BeginPlay on actors) before everything is ready

you want NumTravellingPlayers == 0 and bFinishedLoadingStreamingLevels == true

[ember needle]

well I need the beginplay called on the level BP

no?

[winged badger]

you don't

start everything from AGameMode::InitGameState

right after Super call

its always before BeginPlay

[ember needle]

i'm a little lost, let me see if I can write down everything and if you can confirm

[winged badger]

you can just shoot yourself a BlueprintImplementableEvent from InitGameState

and start the streaming level loads from BP

[ember needle]

@winged badger first of all THANK YOU. please give me a couple of minutes and I'll get back to you

to double check, before I loose 2 weeks on this 🙂

[winged badger]

people keep telling me i should write a blog about that stuff

[ember needle]

YES

😄

@winged badger

• override

void AMyGAMEGameMode::PostSeamlessTravel()
{
    if (GameSession)
    {
        GameSession->PostSeamlessTravel();
    }
}

• separate all the rest in another PostStreamLevelsLoaded or something function:

void AMyGAMEGameMode::PostStreamLevelsLoaded()
{
    // We have to make a copy of the controller list, since the code after this will destroy
    // and create new controllers in the world's list
    TArray<AController*> OldControllerList;
    
    [...]
}

• Have the server send a RepNotify variable with the stream level data, which calls an event on the Main Level BP to load streaming levels.
• Each client notifies the server that the stream levels have been loaded via PS.
• When server has all clients reported for duty, call the PostStreamLevelsLoaded

@winged badger this correct? Also, will this work for players that join in later on?

[winged badger]

might get a little choppy for late joiners

but it won't break them

don't forget starting the streaming level load from InitGameState override

(you can immediately set the variables on GS for clients to receive then)

[limber gyro]

does any 1 know the line of code to check if a pawn is localy owned or not?

[twin juniper]

ANy idea why this would return 'hello' (sorry for repeated repost kept noticing errors with presentation)

[ember needle]

can't I just use the OnRep of the stream levels data?

[winged badger]

and overriding ReadyToStart match to halt BeginPlay

thats the idea

but server has to use something else

ah, fucking BP OnReps fire on server as well

[ember needle]

yep

[winged badger]

yuck

you can, but you still need pre-beginplay post-intializing gamestate hook

to set that data

so override InitGameState, call Super, and fire a custom BlueprintImplementableEvent

to start the rest form GM blueprint

[ember needle]

so then I need to call ReadyToStart after all players have reported their levels to be loaded?

[winged badger]

no, GM calls that every tick

[ember needle]

but if I override it?

[winged badger]

you just need to make sure that it returns false

until its ready

[ember needle]

ah ok

[winged badger]

as for streaming levels themselves, not an expert there, haven't used them much

we brute force generate and spawn the entire level

using similar methods

[ember needle]

@winged badger ok so the end of that would be:

• Have the server send a RepNotify variable with the stream level data
• Override AGameMode::InitGameState, call Super, and fire a custom BlueprintImplementableEvent to start the rest form GM blueprint
• Each client notifies the server that the stream levels have been loaded via PS.
• When server has all clients reported for duty, call the PostStreamLevelsLoaded
• Override ReadyToStart match to halt BeginPlay if not all players have reported their PS.

[winged badger]

out PlayerStarts are not random though, so we don't have to delay HandleSeamlessTravelPlayer like you do

[ember needle]

ah so all of this is for the playerstarts?

yeah indeed

[winged badger]

they won't be in the pool unless the levels are loaded before the starts are selected

oh and also

[ember needle]

but why do I have to Override AGameMode::InitGameState instead of using the OnRep of the stream level data?

[winged badger]

{
    return (Player != nullptr && Player->StartSpot != nullptr);
}```

this abomination

just override it and return false

but you have to set the StreamLevelData from somewhere 🙂

in order for it to have OnRep called

that is what you do from InitGameState override

[ember needle]

AHHH ok so I set it in there

gotcha, lost that

@winged badger SO, the summary:

• override

void AMyGAMEGameMode::PostSeamlessTravel()
{
    if (GameSession)
    {
        GameSession->PostSeamlessTravel();
    }
}

• separate all the rest in another PostStreamLevelsLoaded or something function:

void AMyGAMEGameMode::PostStreamLevelsLoaded()
{
    // We have to make a copy of the controller list, since the code after this will destroy
    // and create new controllers in the world's list
    TArray<AController*> OldControllerList;
    
    [...]
}

• Override AGameMode::InitGameState, call Super, and fire a custom BlueprintImplementableEvent to populate the stream data that gets replicated to clients from the GameState
• Each client notifies the server that the stream levels have been loaded via PC.
• When server has loaded its own stream levels, call the PostStreamLevelsLoaded function extracted from the original PostSeamlessTravel.
• Override ReadyToStartMatch and return false if not all players have reported their PS.
• override:

 bool AGameModeBase::ShouldSpawnAtStartSpot(AController* Player)
{
    return false;
}

[winged badger]

few minor corrections

you don't have to wait for all players to report to call PostStreamLevelsLoaded

you can, but don't have to

server has to finish before you call it, clients are optional

[ember needle]

HA

[winged badger]

server has to have all playerstarts generated

[ember needle]

EDITED ^

[winged badger]

you also don't have to server RPC client progress through the playerstate

you can do it via PC as well

its safer, as PlayerState usually takes its sweet time to replicate

[ember needle]

one last question (at least for now...):

"Override AGameMode::InitGameState, call Super, and fire a custom BlueprintImplementableEvent to populate the stream data that gets replicated to clients from the GameState"

does GameState exist at this point?

[winged badger]

you use PlayerStates to replicate progress if you want to show loading bars

it exists as soon as Super is executed

you can also do a bit of a convenience there if you like

UPROPERTY(BlueprintReadOnly) AMyGameState* MyGameState;

UFUNCTION(BlueprintImplementableEvent) void GameStateInitialized();

virtual void InitGameState() override
{
  Super::InitGameState();
  
  MyGameState = Cast<AMyGameState>(GameState);
  GameStateInitialized();
}

[ember needle]

ok, yet another question: what if I create all of the StartPlayer and then teleport the players after the server has loaded the stream levels?...

[winged badger]

this is better

doesn't create problems if you don't have enough player starts on persistent level

[ember needle]

humour me, this is a learning exercise for me 🙂

let's say I have max 30 players in a game.

I create 30 player starts in the main level (empty)

every stream level has some references (actor arrows for all I care)

when server has finished loading the streams, teleport all players where needed, and also have ReadyToStartMatch return true

...bad?

[winged badger]

you could spawn all actors on persistent level without delaying HandleSeamlessTravelPlayer then

[ember needle]

not questioning you, quite the contrary

[winged badger]

and then teleport the players later

*all players

its just... less elegant

[ember needle]

indeed

[winged badger]

has an extra breaking point in it

more potential for bugs

[ember needle]

oh, which one?

ah ok

[winged badger]

the teleporting itself

[ember needle]

yes

definitely less elegant, however I've an added complexity that I didn't tell you about

the players equipment varies depending on where they spawn

closer to a center, less equipment

[winged badger]

then definitely no on teleport

HandleSeamlessTravelPlayer goes into HandleStartingNewPlayer

its default implementation spawns the player pawns

(you can override it from gamemode, have to call parent to have it spawn default pawns tho)

[ember needle]

ok gotcha

[winged badger]

or just spawn them manually

that is a good hook to handle equipment assignments

[ember needle]

so you're introducing a third option 😄

[winged badger]

and if you teleport after the fact

you don't have it

[ember needle]

so first option: all of the above
2nd option: teleport
3rd option: spawn manually (after server has loaded streams)

this is what you meant?

[winged badger]

spawn manually is only if needed

only if default implementation is not good enough

[ember needle]

i imagine that it kinda kills all of the normal flow