multiplayer

[latent heart]

If you need to reference any other objects, you'd have a 3-way check.

Or 4-way. Etc.

[lucid badger]

So they like check on tick until all are available?

[latent heart]

No. Not tick. Literally begin play.

[lucid badger]

Where/how am I checking repeatedly until they both exist

[latent heart]

BeginPlay of pawn
{
  Does my player state exist?
    Do thing
}

Beginplay of player state
{
  Does my pawn exist?
    Do thing
}```

[lucid badger]

But they have to Do thing eventually, it's not optional

[latent heart]

Then no matter the order they actually replicate, the "do thing" only happens once.

[lucid badger]

Oh

I get you now

[latent heart]

Pawn replicates
- Does player state exist? No. Nothing happens.
Player state replicates
- Does pawn exist? Yes. Do thing```

Regardless of the order, the last object to replicate always triggers the action.

[lucid badger]

got it

[latent heart]

You could probably generalise it into a system.

A world subsystem probably

I believe there's a maketplace plugin that does exactly that.

[lucid badger]

Seems simple enough to make

[latent heart]

I'd do something like a map of maps which linked to an array of callbacks. Objects could then either call an event by name or register a callback that required a certain number of events to have happened. An event could be anything.

Maybe some custom handling for certain event types, like "has my player controller been replicated?"

"have all player states been replicated"

And so on.

[lucid badger]

for this I'm just gonna move everything on beginplay on both pawn and state to a "PawnAndStateReady" event on each, and call both from whichever beginplay is second

[proven grove]

Hey guys, I have some questions regarding the PlayerState's class and how to keep data between server travels.

• I know that the PlayerState is replicated to all clients, but does that mean that EVERY data stored in the PlayerState can be accessed and viewed by others clients? I need a way for my backend to identify clients with a unique identifier, something like an ID (not the game ID but a custom ID from my backend), can this probably be a security issue if the ID can be seen by others? (I don't think so since only the Unreal servers will be able to do API calls)

• Can a client modify the variables inside his PlayerState or the gamemode is the only one able to do so? If I store an unique identifier about a client I don't want them to be able to fake the identifier and pretend to be someone else to my backend

[lucid badger]

Doh, was having a weird issue, forgot that on server they are both available when you beginplay--so I was firing both twice 😵‍💫

[lucid badger]

Print Text/String from blueprint seems to just not fire when on the client? At least in one-process mode. But on a separate process, AFAIK those nodes don't work ("Development Only")

How does one print from client's perspective for debugging purposes?

[meager stratus]

Hello, i am dipping into learning cpp replication. A quick q'n - is "push replication" kind of the state-of-art at the moment and what I should focus on?

[fossil spoke]

Push Model is just an optimization mechanism.

There is nothing "state of the art" about it.

Just focus on getting generally aquainted with Replication.

Learn the basics.

Get good at the basics.

[lucid badger]

I set up an RPC that lets the client send a message for the server to print works for now

Interesting. It seems that for the client, both Pawn and State call BeginPlay before they are even connected to each other (using GetPawn vs. GetPlayerState to get each other returns nullptr)

[0028.21][760]LogTemp: Error: DEBUG FROM CLIENT: Pawn was not ready!! Skipping state...
[0028.21][760]LogTemp: Error: DEBUG FROM CLIENT: State was not ready!! Skipping pawn...

[icy jetty]

Begin Play events can fire at various times

[lucid badger]

If 'various times' includes 'before OR after possession' then this strategy ^ won't work, right?

So I do need to do it from OnPossession I suppose

[sweet sage]

Maximum number of UObjects (0) exceeded when trying to add 1 object(s), make sure you update MaxObjectsInGame/MaxObjectsInEditor/MaxObjectsInProgram in project settings.

How do i fix that?

How do i fix that on backend

[mystic marsh]

You can control which clients can see what properties using DOREPLIFETIME_CONDITION, read here https://docs.unrealengine.com/5.3/en-US/property-replication-in-unreal-engine/ and then follow it to conditional replication. An additional answer for owner-only properties is that you can replicate them on the player controller instead - only the owning client and the server see the controller at all.

Clients should not modify replicated properties, only the server should. No change the client makes to a replicated property will make it back to the server. The only way for clients to accomplish anything on the server is to send an RPC.

[lucid badger]

I have a multicast RPC in PossessedBy but it never makes it to the client

I'm thinking it's because... the moment when the client's pawn is possessed by the client's controller on the server is not necessarily the same as when it is possessed on the client's system

[quasi tide]

Correct

[lucid badger]

Okay so like

If I can't use begin play

And I cna't use possessed by

How do I set up stuff that requires both PlayerState and Pawn to be ready and linked

When I tried to use the begin play double latch thing

It doesn't work because apparently, on client, BeginPlay fires on both Pawn and State before possession occurs

So what fires on the client and after pawn and state are linked?

[quasi tide]

AcknowledgePossession more than likely

[lucid badger]

[quasi tide]

This is what I use to do most of my client setup stuff with controllers

There is also a ServerAcknowledgePossession

[fossil spoke]

You are doing something very wrong if you are getting a weird message like that

[lucid badger]

Oh yeah that sounds like exactly what I need

[mystic marsh]

I've got OnPossess and AcknowledgePossession overridden such that they both call a common function after they do their other work. It's an annoyance that there isn't a built-in common function for that.

[lucid badger]

Can you elaborate on this?

[sweet sage]

I have modified unreal source
From this:

FORCEINLINE static bool PhysSingleThreadedMode()
{
if (IsRunningDedicatedServer() || FPlatformMisc::NumberOfCores() < 3 || !FPlatformProcess::SupportsMultithreading())
    {
        return true;
    }
    return false;
}

To this:

FORCEINLINE static bool PhysSingleThreadedMode()
{
   return false
}

Is it wrong?

[mystic marsh]

On which part? How to override a function?

[lucid badger]

No on what you're doing in the common function or

[mystic marsh]

Doing whatever both client and server need to do after possession

[fossil spoke]

Jesus why.

Also how does this have anything to do with #multiplayer

[sweet sage]

It is a backend for multiplayer mmo server

[fossil spoke]

You are way out of your depth here

[lucid badger]

https://github.com/tranek/GASDocumentation#concepts-asc-setup just noticed in here that it suggests using OnRep_PlayerState

Oh cuz mine is ASC on PlayerState

Wish I had seen that 1 hour ago

[mystic marsh]

There's a whole other channel for GAS stuff FWIW.

[fossil spoke]

Yeah please use the appropriate channel for #gameplay-ability-system discussion.

[sweet sage]

It is strange that limit is 0 Ubjects(0)

[fossil spoke]

No, its not. Because you are forcing something into a state thats its been specifically coded not to be in.

if (IsRunningDedicatedServer() || FPlatformMisc::NumberOfCores() < 3 || !FPlatformProcess::SupportsMultithreading())

This is extremely important, especially given its context.

Multithreaded Physics

DO

NOT

MESS

WITH

lol

[sweet sage]

I have changed back this part of code and recompiled unreal

[lucid badger]

?? what? I was talking about multiplayer for 99% of this subject

[sweet sage]

It has same error

[lucid badger]

I only mentioned GAS offhand

Super aggressive and weird to come at me for that o_O

[fossil spoke]

I cant help that you interpretted that as agressive. My intention was only to make you aware of the channel.

[lucid badger]

"Please use the appropriate channel" means "This is not the appropriate channel"

I'll leave it at that

[fossil spoke]

If this wasnt the appropriate channel, i would have said that.

[lucid badger]

Aight then I misunderstood you

[fossil spoke]

This is not the channel you should be asking for help with this issue.

#cpp is where you should be asking.

[lucid badger]

How do I permanently set net.UseAdaptiveNetUpdateFrequency to 1

Seems to revert to 0 on editor restart

Presumably that means it's always 0 in standalone

[quasi tide]

Need to find where that'd be in one of those .ini files

[lucid badger]

I see will peek around

[icy jetty]

But wait I wanted to see you continue fighting with the mods! 🍿 😀

[lucid badger]

For future searchers, it was:

[SystemSettings]
net.UseAdaptiveNetUpdateFrequency=1
in config/DefaultEngine.ini

[bright tiger]

Which is the way to go when doing an object pooling in network?

[fossil spoke]

That question is a little broad. Can you go into specifics of what you are trying to achieve.

[bright tiger]

I want to create a bullet projectile pool of 1000 projectiles, and a way to do this in a multiplayer game.

But I get confused fast

The problem is that I could replicate the object pool of projectiles itself but that may create a massive overhead.

Or separate each object pool by its own version on each client and then a way to “sync” those projectiles in the server.

But I’m quite lost that’s why I ask how it’s actually achieved usually.

[dark wing]

How would you replicate the object pool?

Object pooling shouldn't be replicated

There is no need for confusion, you just use object pooling methods to show and hide the projectile instead of spawning the actor and destroying it

Simple and easy

Start with 10 projectiles that are spawned when joined to the server,

Server To Client (bullet is shot, spawn a projectile)

Client will check if there is an actor in the pool that can be used, if yes then proceed (reset the values and show the actor), if no then spawn a new one and add it to the pool

there is no need for replication

The only thing you may want to replicate is objects count in the pool, server can replicate this value when a new client joined to server, then the client will spawn the projectiles and add them to the pool

[bright tiger]

This is a multicast approach but what happens if you want to replicate the projectile movements (the projectile actor itself)?

Multicasting implies that bounces and path may differ between clients. Plus what about physics caused by such projectiles, they 100% different from clients and server would correct every single physic reacted actor.

[sinful tree]

All that should be required is:

1. Spawning an actor on the server that isn't marked as replicated, but has replicated properties and calling the SetNetAddressable() function on it.
2. Spawning an actor on a client of the same class, named the same thing, and then calling SetNetAddressable().

Your actor should now be addressable across the network.

If you wanted 1000 of these actors, you could do something like...

1. Create an actor set to not replicated, that has an integer exposed on spawn (not replicated)
2. GameState Begin Play > For Loop (last index = 999) > Spawn Actor feeding in the index of the loop to that exposed integer.
3. Add the projectile to an array (not replicated) on some actor (like gamestate, or create something like a "pool manager" actor)
4. Begin Play of the projectile actor > Rename itself to "Projectile_" + "Your integer value" > Call SetNetAddressable()

When the server starts the gamestate, it'll call begin play, do the loop spawning all the actors and naming them, and making them netaddressable, however, they are still not considered replicated actors.
When a client joins the game, they'll do the same, spawning local copies of those actors, renaming them to the same thing, and marking them as netaddressable. An actor channel should then be opened for each of those projectiles and any replicated values will begin to propegate. As you use your projectiles you can keep track of which one was last used, and grab the next actor from the array, and increment your tracking index until it gets to the length of the array, then start at 0 again.

I may be wrong about this, but I think in the end it's technically not going to save you very much by not replicating the actor pool to begin with, as the spawning of actors and replication of values still has to take place regardless when the client joins.

[latent heart]

From whichever event makes sense. Ogre has good suggestions.

[lucid badger]

Ended up doing OnRep_PlayerState by reccomendation of the GAS Bible everyone passes around 😛 Thanks though

[summer tide]

Anybody knows how to replicate BreakConstraint function?

[latent heart]

Create a wrapper rpc function which takes the same parameters? Or, better yet, have a replicated 'state' value which you respond to onrep to break the constraint.

[summer tide]

I was able to replicate SetConstraint using Server->Multicast->SetConstraint. So as you know now, i'm using Blueprint

[latent heart]

Everything I said is possible in BP.

[dark parcel]

Trying to replicate struct for the first time

[latent heart]

The reason for a state for this is that any players joining after your RPC will not have the broken constraint, because they missed the rpc.

[dark parcel]

i changed it but my on_rep not triggered 🤔

[solar stirrup]

In C++?

[dark parcel]

Yes but it's not triggered for both server and client

[solar stirrup]

If so, rep notifies in C++ don't run on the server

You gotta call them manually

Client that's weird

Did you mark the actor/component as replicated?

[dark parcel]

bReplicates = true I suppose?

[solar stirrup]

Yes

Component needs to replicate too if you're doing it in a component

[dark parcel]

not doing component

never got the msg printed in either the server or client

I thought since the Variable is set on the server, it will replicate the value back to client and the msg should be printed on client side

[solar stirrup]

Did you add the replicated property to your GetLifetimeReplicatedProps()

[dark parcel]

Is that required for Repnotify ? That might be the issue then

thought that's required only for the ones marked as replicated

[solar stirrup]

It is required for any replicated property

[dark parcel]

Got it , tysm. Gonna try that

[solar stirrup]

The engine warns you about it when you start the editor ^^ check output log

[dark parcel]

LogClass: Warning: Property AGCharacterPreview::CosmeticDataLip (SourceClass: AGCharacterPreview) was not registered in GetLifetimeReplicatedProps. This property will not be replicated. Use DISABLE_REPLICATED_PROPERTY if not replicating was intentional.
🦦

[summer tide]

So I assume I have use server->Multicast on BreakCOnstraint

[latent heart]

No

You don't need the RPC at all now

Well, unless you're telling the server to break the constraint. If you're doing that, you need an RPC, yes.

Once the server knows to change that bool value, no extra rpcs are needed.

What is that top-right node meant to be doing?

And where is this chain of events initiated? What's causing the constraint to break?

[dark parcel]

@solar stirrup All is well now! Thanks for your time

[summer tide]

So are you saying I don't need to use Server and Multicast to call the set and break constraint functions

[latent heart]

So, with this, do you expect your set w/ notify nodes to update the value on the server when the client presses 'M' ?

[summer tide]

I guess not

So what is right thing to do

[latent heart]

When you hit M call a server function "Toggle Mount" (or whatever)

That's all you do there.

In that server function, you do all the other stuff from your last screenshot.

[latent heart]

In this function, don't call another RPC. Your "true" output should re-add the physics constraint.

[bright summit]

any idea how to replicate this? Via Server RPC? I think not because calling rpcs while timeline updates will be much data consuming, or am I wrong?

[latent heart]

Tell the server when you start to crouch (and when you stop) and let it do its own timeline.

[bright summit]

ah, yeah

[thin stratus]

Seems backwards what I see in the image

You could just call crouch and then react to the OnCrouch callbacks

The code above would fail if the server rejects the crouch call for whatever reason

[lucid badger]

Anyone hit me with a sanity check? I'm thinking to expand my item system to MP I'll have an item manager actor that owns all items and inventories (both are UObjects) in the session.

Actor exists for all players, when server makes new items (or a player joins with items) it syncs new items to all player's ItemManagers. Items have a GUID and are passed around by GUID (so if client wants to pick up or drop or equip item, RPC to server with its GUID for verification/execution).

Whenever item state changes (changeable item state is very limited -- grid position, isrotated, etc.), RPC to clients with new state which is updated in the manager.

Aiming for 4 players max in a session, players can really only move items like 1 per second (click/drag grid inventory). That's a pretty reasonable amount of RPC calls, right? Just the occaisional "Oh I want to move this to another inventory spot" "Oh I want to drop this item" "Oh I want to pick this up?"

[bright summit]

yeah sure, but the problem is when I call crouch firstly then lerp the capsule height it starts jittering because crouch function changes capsule height instantly

[thin stratus]

Override the behavior in your own CMC?

Or character

Pretty sure it's changed in the OnRep for the crouch Boolean

@bright summit

[bright summit]

can I override it in blueprint? Sorry I am just switching from Unity and I am learning Unreal now

[thin stratus]

Honestly, RPCs for that sounds a bit mäh. Inventories are better done via FastArraySerializer

[lucid badger]

what is that

[thin stratus]

Most likely not. But if you just switched let me tell you that Multiplayer will require c++ eventually

[quasi tide]

It makes replicating an array go brrr

[lucid badger]

An array of what

[thin stratus]

@lucid badger C++ custom array serialization

[quasi tide]

w/e your little heart desires

[thin stratus]

You would replicate the item of course

[lucid badger]

UObjects have to be manually replicated though right

[thin stratus]

They just have to be handled by the actor you have the inventory in

But yes

[lucid badger]

What exactly do you mean by handled? My understanding is I have to straight up serialize them (i.e. a struct with relevant state to reconstruct it on the other side)

[thin stratus]

UE has subobject replication via the actor channel

[summer tide]

If I don't use Server SetContraint it doesn't work for client

[thin stratus]

That's somewhat how Components work anyway

[bright summit]

I know, but trying to do everything in BPs if I do not must use C++. If I would want to override crouch behaviour I must do everything in cmc with c++

[lucid badger]

Can you link me something on this? What I was reading is that UObjects can't sync. They can if they're attached to an actor? Like in a TArray?

That would be very useful

[thin stratus]

Most likely. All I can say is that BP Multiplayer will hit limits very quickly. You reached one, which is Movement

[latent heart]

Then something else is wrong.

[thin stratus]

Just Google Subobject replication tbh

I haven't set that up in a while

And it changed slightly in 5.x

[bright summit]

yeah that's the reason I asked about general movement component is it worth to buy it for simple movement like in goldsrc

[lucid badger]

That might be why I thought you couldn't do it, a lot of the resources I find are 4.x

[thin stratus]

You def don't need to parse a struct back and forth @lucid badger

[thin stratus]

Maybe. I never used it or had the need for it :/

[lucid badger]

I found this, gonna read now https://docs.unrealengine.com/5.3/en-US/replicated-subobjects-in-unreal-engine/

[bright summit]

I think for simple things I need it is not worth of buying it, and that's why I am trying to do some more complicated things in blueprint. If it will be needed I will just do it in c++ but for know trying to avoid that

[thin stratus]

The problem is that UE has a lot of default assumptions that you can't override in Blueprints

Crouch capsule height being one

You could see if you can change the crouch height in the defaults to the same height as standing

And then do it manually afterwards

[quasi tide]

Hopefully mover 2.0 addresses this kind of stuff as well to be honest.

[thin stratus]

Not sure if the OnRep is perfectly synced between owning client and server

So it might be that they fight over movement if you walk below a low ceiling at that moment

[bright summit]

the biggest problem here is that UE has server-auth movement which I don't need

[thin stratus]

Then disable it

[bright summit]

lol

[thin stratus]

CMC has a Boolean for it

[bright summit]

wtf

[thin stratus]

Which trusts the client with location

[lucid badger]

Yeah see I had a feeling there was something for this, glad I asked

If I can replicate Objects directly that'll be sooo much easier

[thin stratus]

Your usual approach should be an OnRep array. The better approach is the FastArraySerializer

[quasi tide]

UE5 made it sooo much easier than how to do it in UE4

[thin stratus]

For 4 players you could get away with the OnRep if the array is smallish

[lucid badger]

array of what?

I'm still not clear on where the array comes into play. You mean just when a new player joins (i.e. multiple items need to sync at once?)

It will generally be very rare for more than one item to update state within a given second or so

Or I suppose just at the start too, after map generates items

[quasi tide]

The array of w/e you have an array of

He's just speaking generalities

[lucid badger]

I don't have anything in an array

[quasi tide]

How does your inventory work?

[lucid badger]

Inventories do have an array of pointers to objects they contain, but that's just for lookups, items themselves define where they are so it's like a nested structure.

I was suggesting having an actor that owns all session's items and handles the syncing but those items would only sync one at a time as small changes occur?

[quasi tide]

I don't have anything in an array

Inventories do have an array of pointers
🤔

[lucid badger]

It wouldn't make sense to sync from that direction is what I Mean

A list of all items is enough without worrying about how they are nested, since they are linked directly to each other rather than 'in a collection'

But I guess what yer saying is, when players are joining (i.e. need to sync a bunch of items at once) this would come into play?

But it sounds like this subobject sync stuff is entirely automatic

I didn't mention that items can themselves contain an inventory, which is why it gets all wibbly wobbly

[thin stratus]

@lucid badger I don't know how your Inventory exactly works, but usually Inventories are an Array of Something.
Array of Struct, Array of Object.

There is no need to sync anything for new Players that join, that's why it's an OnRep Array, or FastArraySerialized Array.

Server adds to it, new Clients will automatically get the latest version.

OnRep or FastArray callbacks to update UI.

[bright summit]

I did something like this, everything works except when seeing other cliens crouching - they are still jittering 🤔

[lucid badger]

Yes, okay, that's what I meant by the manager. The manager will have the array

Where items actually are is irrelevant, the manager will have the 'master array' of all items

[bright summit]

when client sees other clients*

[thin stratus]

If your items don't have any state, so you just reference some unique ID, then it's an Array of Ids fwiw

Not sure what the Object would be for then

The part with the Object is in case your Items are objects you wish to replicate

Which most people usually do

[lucid badger]

They do have state

The unique id won't be necessary if we can just replicate the objects, I think

Which it seems like we can, wiring it up now

Having trouble finding any resources regarding the FFastArraySerializer. This page is not very enlightening https://docs.unrealengine.com/4.27/en-US/API/Runtime/Engine/Engine/FFastArraySerializer/

[quasi tide]

Read the .h file

[lucid badger]

Ooh

[plucky prawn]

can subsystems have replicated properties?

[latent heart]

No

Subsystems like game instances, are owning-instance-only.

[plucky prawn]

gamestate it is then

[quasi tide]

Workaround is to have a proxy actor

[latent heart]

GameStates can have components

[lucid badger]

It sounds like this one is for Arrays of UStructs, not UObjects

[latent heart]

Those components can be replicated.

[plucky prawn]

ye a component is actually a good af idea

[latent heart]

I have all the good ideas, don't you know?!

I had a fantastic idea about gamemode/states with components to separate out different states of play.

Basically a sort of "game mode component" which has a very similar interface to the game mode itself with enter/leave methods and the game mode just forwards everything to the currently active component.

[plucky prawn]

sounds sandboxy with modding potential

like gmod gamemodes

[latent heart]

uscript had a similar idea where you could specify states and then you'd move between states and different sets of functions became active.

[plucky prawn]

thats actually interesting af

is there resources i can learn more about how this works?

[bright summit]

ook can't understand UE replication system, any good tutorial to explain it? XD

[plucky prawn]

check the pins

[latent heart]

The pins in this channel.

[latent heart]

uscript from udk?! Try 2010!

[bright summit]

ok thanks, don't know really where is the difference between Unity's NGO and UE replication, both systems are server-auth

[lucid badger]

What is an "OnRep Array"? Fast Array Serializer appears to be for UStruct not UObject

[plucky prawn]

unreal's isnt deprecated

[bright summit]

NGO =/= MLAPI

[thin stratus]

That struct can contain everything else though

[lucid badger]

Oh, it can contain a uobject?

Interesting

[thin stratus]

OnRep Array is an Array property that uses ReplicatedUsing to specify an OnRep function that calls when the property changes via repkication on the client

If that concept is new to you then you should read the Compendium that is pinned to this channel

Cause that's basics

[lucid badger]

I read the compendium at the outset of this journey about 10 hours ago. I should definitely read it again now that I understand any of it now

I was completely clueless 10 hours ago so not a lot of it stuck, looking at it again now

[zenith kestrel]

I need help or maybe tutorial on how can I give team tags to player before match start and how can I switch them in between match let's say after half time in pvp game

[prisma snow]

Hey! Forwarding my message in case it got lost and somebody has input

[chrome bay]

The best thing to do is use OnRep callbacks

BeginPlay for initialization unfortunately doesn't really carry over so well in MP for these reasons.

But you can skirt around those issues using OnReps to drive initialization when those actor refs change

[prisma snow]

Interesting, that would indeed ensure that replication is complete before calling those functions. Does OnRep get called on server too even if the value didn´t change? Else I´d have to call it manually

[chrome bay]

Nah only on receiving Clients (unless in BP)

[prisma snow]

ye thought so, well, for server I could use Begin play since this issue only affects clients

[chrome bay]

You should just be able to have some common initialization code you follow, you can still call TryInitialize() from BeginPlay or something, it just silently/gracefully drops out unless all the references are set, and you keep calling it from each OnRep

[prisma snow]

yeah excatly. Some initialization works fine, it´s just the parts that depend on other actors that fail

thanks a lot for the advice 🙂 Has been a long running problem that I wanted to solve properly

[bright tiger]

And its "correct"/"acceptable" to have 1000 actors replicated with replicated movement at the same time?

Will that kill the network?

[prisma snow]

in my testing 100-200 characters with replicated movement already killed the network

it´s not only the volume odf the data, but also the fact that there are 1000 actor channels open

like

sending 1000 movement updates per actor is more expensive than sending 1000 updates on an array with a single actor

I have tested 1k units in real network scenario with custom setup based on arrays sent on rpcs

but updates were happening once per second

[bright tiger]

Is there any diference on calling a Multicast in the server that spawns a bullet in server and all clients against spawning the bullet in the server and then multicasting? Going straight to Multicast will have any downsides?

[bright tiger]

So the way to go is always multicasting and spawning local instances that are not synced?

[fiery wadi]

General MP question, Would you guys have a different Game Mode for each "section" of a MP Game ? So like the MainIntro (Ie...Welcome Screen etc) then a new Game Mode for a Lobby Area, then another Game Mode for "InGame Game Mode" I,m just asking as I see a lot of tutorials and such that go creating a Game Mode specifically for the Lobby area but they dont really explain "Why this is the case", So wondering if its the "Norm" or if it,s just to make the tutorial easier to understand. Obviously each of these would be encased in their own levels (MainIntro Map, Lobby Map, Game Map)

[prisma snow]

Idk if it's the way to go always, each scenario requires different considerations

I would think of the cheapest and simplest way to implement it and go from there

Like for example, if you make a projectile simulation and the projectile whole trajectory can be precalculated, then you don't even need to sync anything besides initial launch

[lucid badger]

@prisma snow I was just dealing with these race conditions last night with Pawn vs. PlayerState--my Pawn needs PlayerState to init, but engine was firing BeginPlay on both Pawn AND PlayerState before even possessing the pawn! Solution was to use OnRep_PlayerState for client init and OnPossessed for server init

[prisma snow]

great to know, thank you a lot 😄

[bright summit]

Replicates bool in variable settings it means that when set on server it automatically is synced in other clients, right?

[lucid badger]

My understanding as a guy who learned this all yesterday: Yes but not necessarily instantly, depends on replicate frequency and priority and stuff

[bright summit]

🤔 I think that's the point

why my bp is not workign

thanks

[lucid badger]

If you have something on the client that is waiting for that bool update to arrive

I believe you can just override OnRep_<boolname>

Which will get fired as soon as the client gets/applies the update

[bright summit]

oh I forgot about that

yea that will be better

[lucid badger]

Might be good if someone with >24h of expertise on this confirms 😅

[bright summit]

[unkempt tiger]

Im not sure if this is the right place to ask, but does anyone know why Epic decided to use SearchObject->QuerySettings.Set(SEARCH_PRESENCE, true, EOnlineComparisonOp::Equals); inside the default find sessions node UFindSessionsCallbackProxy::Activate()? Does this not immediately make dedicated servers unsupported, since they can't have presence?

[lucid badger]

I'm pretty sure dedicated servers are supported

[unkempt tiger]

its listed in the steam documentation https://docs.unrealengine.com/4.27/en-US/ProgrammingAndScripting/Online/Steam/

if I make sure bUsesPresence is false, it means I can't find my session :/

[thorn turtle]

I currently have 2 issues, one being when I play certain player animations it play for everyone on their screen but on anybody else's. The second is that I can get actors other than the player to work on both the client and the server but it only syncs if done from the server. I know its something to do with replication but even after reading the documents I don't understand what I'm doing wrong

[fossil spoke]

Likely because it was an oversight. 🤷

[fossil spoke]

Show your code.

[thorn turtle]

This is for the interaction with other actors, I've done it in a bunch of ways including using events to send it to the client and the server but it only goes across when I use the server player. I did try to use Switch has Authority too but that didn't work either

this is the code that sets the variable, this tells the blendspace to do a certain animation when running, walking and idle. I'm relatively sure other players can't see the animation because of the variable but I'm not sure how else to do it and I'm not sure on how to have it set so other players can see it. It also plays for ALL players on the side that it done from

[latent sapphire]

I made a system for making a character sit and it works fine on the host but doesnt on the client

[fossil spoke]

Can you repost the image bigger.

[latent sapphire]

yes

[fossil spoke]

Also, it really helps to keep your nodes organized.

[latent sapphire]

is that not organized?

[fossil spoke]

If you were working for me, I would reject it until it was better. Ill put it that way.

[latent sapphire]

alright my fault

as big as i can get it

[fossil spoke]

What class is this in?

[latent sapphire]

character

[fossil spoke]

This is bad practice

In 99% of cases you should never use Colored lines across White lines.

White lines represent seperate executions

Using results from other executions is likely to cause you issues.

If you need the result from a separate execution, in another execution.

Save the result in a variable

[latent sapphire]

ok

[fossil spoke]

Your LineTrace code should probably be its own function

So you can call it where you need it.

WidgetTick is also a terrible name

Its not Ticking any Widget at all.

All its doing is adding/removing a Widget from the viewport.

[latent sapphire]

im sorry

[fossil spoke]

You dont have to apologies lol

[latent sapphire]

it was a quick name

[fossil spoke]

Im just pointing out issues.

These things matter.

[latent sapphire]

i thank you for pointing those out though

[fossil spoke]

As it makes your code less understandable if you have bad naming conventions.

[latent sapphire]

ok my fault

[fossil spoke]

And its likely to be yourself who has to read it again.

So if you name something badly, are you going to be able to understand its purpose at a glance?

[latent sapphire]

im still pretty new to blueprints

[fossil spoke]

Thats fine.

[latent sapphire]

fair point

[fossil spoke]

We all start somewhere

Programming is a lot about attention to detail.

There are rules and structure for a reason.

It all matters.

[latent sapphire]

alright

thanks for the pointers

[fossil spoke]

Why are you doing this

[latent sapphire]

so it moves the player to the seat while the player is sitting

[fossil spoke]

This is calling an RPC every frame, that sets the location of the Actor on the Server, every frame.

Why are you not just calling it once?

[latent sapphire]

the chair is moving most of the time

[fossil spoke]

Ok so you probably should instead Attach the Player to the chair.

[latent sapphire]

ok

how would i do this?

[fossil spoke]

AttachToActor

[latent sapphire]

ok

[fossil spoke]

Or something along those lines, I forget the BP names

There are functions for it

And then you would do the reverse Unattach when not sitting

[latent sapphire]

attach component to component

[fossil spoke]

Sure

You want to use the RootComponent of the Player

Which is also a function GetRootComponent

To the Chair (im guessing it has a static mesh component)

[latent sapphire]

yes

[fossil spoke]

Once you setup the attachment code, you should remove the Delay and make sure you arent calling it over and over

That is also bad practice.

[latent sapphire]

yes

[fossil spoke]

You should never call Reliable RPCs every frame

Unreliable RPCs are fine

Reliable are not

[latent sapphire]

ok

[gritty valley]

If I replicate a Text to client in BP and reference a Stringtable entry, will it replicate the whole text, or just the reference?

[thorn turtle]

how do I get a reference to the actor in charge of the server, I want to use it for a branch so it doesn't activate nodes twice if it is the server player doing it

[fiery wadi]

No one able to answer my question please? (General MP question, Would you guys have a different Game Mode for each "section" of a MP Game ? So like the MainIntro (Ie...Welcome Screen etc) then a new Game Mode for a Lobby Area, then another Game Mode for "InGame Game Mode" I,m just asking as I see a lot of tutorials and such that go creating a Game Mode specifically for the Lobby area but they dont really explain "Why this is the case", So wondering if its the "Norm" or if it,s just to make the tutorial easier to understand. Obviously each of these would be encased in their own levels (MainIntro Map, Lobby Map, Game Map)
Copied from original post.

[fossil spoke]

Yes, typically you will have a GM for just the MainMenu and then any other Gameplay Levels will have a mode to embody what they are doing.

[fiery wadi]

Thank you for that answer! 🙂

[fossil spoke]

Different levels might support the same types of GMs

So like, if you have a Capture The Flag mode.

You dont need a CTF_GameMode_Level1, CTF_GameMode_Level2, CTF_GameMode_Level3 etc etc

You only would need CTF_GameMode

[fiery wadi]

Ok I mainly asked because i got a Menu System from the Marketplace and it uses a Game Mode called MainMenuMode and when I load someone into a Lobby Map So i should be using another Game Mode on the Lobby Map then 🙂

[fossil spoke]

Sure, i guess...

[latent sapphire]

is this better

but im running into a error

accessed none

for the cast

[fossil spoke]

You are still using colored lines across white lines

You need to stop thinking you can do that

[latent sapphire]

oh i see

[fossil spoke]

Especially with RPCs

You may need to pass that through the RPC as a parameter

I would pass the Chair as a Parameter

[latent sapphire]

ok

[upbeat basin]

I just realized setting the Instigator and checking if that pawn is locally controlled is the perfect way for this

[umbral patio]

is it possible to replicate subobjects inside subobjects?

[fathom aspen]

Sure, as long as you're able to get to the outer actor that replicates them

[noble sentinel]

how can I replicate spawn decal node?

Classic Run on server - multicast isnt doing anything(I think its because spawn decal command is client only anyways)

[sinful tree]

Is this an actor that is owned by a player? Are you getting any warnings or errors in the log? If this is not a player owned actor, you wouldn't be able to call a Run On Server event on this actor which could be the cause of the problem.

Just to note, each client would effectively generate their own random values for the size. If you want it to be consistent, you'd need to generate the size based on a seed on the client, or have the server generate the value and send it through the RPC.

You'll also run into an odd behavior here where connecting the same pure node to an executing node will result in the same single random value being used for all values. So if you generate a "40", it'll set 40 for X, Y and Z - if you want each to be different, you'd have to use separate random nodes.

[noble sentinel]

Its player, when it hit another player it spawns a decal behind him(blood splatter on wall). But only player can see the decal from his hit, even server.

Like this video

[torpid lantern]

Are they spawning at 0,0, 0 by chance?

[sinful tree]

Might have to do with how you're calculating the traces start and end.

[noble sentinel]

I guess problem is this, its only working on client. But I dont know how to make it run on server?

It is saying "Does Not Replicate"

[sinful tree]

That isn't the problem.

"Multicast" == You're running on all clients (and server!)

[noble sentinel]

oh

Glad its like that

[noble sentinel]

I didnt get this

[noble sentinel]

Im checking it

[sinful tree]

We don't know what you're using for these values.

[torpid lantern]

I would slap a print on the start/end vector and see if you're getting 0s. You might need to replicate those vectors or recalculate them clinet-side.

[sinful tree]

If you're multicasting, you could potentially be grabbing values that don't exist on other clients.

[noble sentinel]

these are coming from this

which is my gun line trace thing

[torpid lantern]

or pass them through in the MC

[noble sentinel]

I checked and I think they arent, I will try printing

[sinful tree]

Ok and that's part of the problem - that first trace you did probably only happened on the client, so the hit result you're pulling the data from didn't happen on other clients, so it could result in invalid values.

As Pumpkin is saying, you'll need to send the values through the multicast.

[noble sentinel]

Ok Im trying to do that now, thanks

[torpid lantern]

Amazing! Let me know how it works out.

[noble sentinel]

This part right?

Should I do run on server -> multicast or only multicast?

[dark edge]

@noble sentinelWhat are you trying to tell the server?

In plain English

[noble sentinel]

When a decal spawned for a player, it should spawn for everybody

[dark edge]

Spawned how and why

WHat is the action

[noble sentinel]

this event happens when my line trace for gun contacts with body, creates another line trace to wall then creating a decal

[dark edge]

So the thing you're trying to tell the server is "I just shot this thing at this location with this direction" right?

This is clientside hit detection but it's fine for now, make an event that passes over an actor ref, a vector position, and a vector direction.

You tell the server "I shot Actor at Location and the bullet was going in Direction"

[noble sentinel]

Got it work!

Thank you very much for help

Replicating the line trace for guns was the needed thing

[torpid lantern]

Huzzah! Good job.

[dark edge]

Just remember, replicate the bare minimum amount of state and drive other things with it. You don't have enough bandwidth for the entire games data to fly across the network, you need to replicate stuff like "This character shot in this direction" or "This thing got hit with a bullet and took x damage" etc. The cosmetics can be calculated based on that.

[noble sentinel]

Now I guess I need to solve why its always spwaning at same single height

[noble sentinel]

Yeah but Im very new at this

[torpid lantern]

You might want to click on SplatterMC and add two pins for the vectors, instead of replciating all the traces ever.

[noble sentinel]

so I dont really know what really needed

[dark edge]

Start with JUST sending the fact that a hit happened

let everything else be calculated from that

Hit happened, this guy got hit at this location and in that direction

that's enough to calculate the splatter stuff independently on all machines

[noble sentinel]

Is it making server load heavier when I send all data? Im making a game for like 20 players so I guess I should do more optimization right?

[dark edge]

That and it's unnecessary and will introduce all sorts of problems

Like, you don't replicate the pose of a skeleton while it's running

you replicated it's position and speed, and let the pose be calculated by the animBP

You don't replicate the pixels in a texture, you replicate a reference to a texture or just a boolean

You don't replicate PlaySound and PlayParticles and DoRecoil, you just replicate FireGun

[noble sentinel]

I got it, Im actually isnt replicating thing as long as they work lol

[noble sentinel]

But I didnt get why this height isnt replicating even tho I replicated all vectors?

Its look like working correctly but somehow height position is wrong

[dark edge]

Show what you're replicating and hwo you calculate the height

First, show the message that's sent to the server

[noble sentinel]

First Im sending this

[dark edge]

Follow Camera isn't synced up

It's not pitching

[noble sentinel]

Oh so this is same thing as flashlight replication right?

Its also working horizontally but not syncing vertically

[dark edge]

yup

ControlRotation is local

So what you're replicating is the fact that the gun was fired

That can be fine, but remember, everyone will slightly disagree on what direction things are pointed etc at that moment in time

[torpid lantern]

As an aside and not to distract from Akane's issue.

I would really appreciate an architecture consult. For context, I am very new to object oriented programming.

Background:

• Game is run on dedicated server
• Players control 3-5 units per session
• Unit state is persistent and managed by server while player is offline (other players may log into server and interface with these units)

I’m wanting to figure out the most performant way to manage unit states & tasks; specifically which game object makes the most sense. Should this be its own object?

For example: player tells units A, B, & C to mine rocks, chop wood, then fish – in that priority. The timing of each collection is variable. Server needs to maintain a list of task requests, manage when unit is available, and assign task based on unit’s attributes.

Object Considerations:

• Custom Master Object – I don’t know if I need a master “master object” to house this logic and I don’t know the questions I should be asking myself to answer that question. I’m also a little concerned about jamming too much data into one object; but I’m not sure if that’s even a thing in OO.
• Actor Component - Maybe an actor component that I can plug on the units, but this feels like Custom Master Object with more steps.
• Game State / Game Mode – I don’t quite understand the difference between these two TBH, but Game State sounds like it would work.
• Player State – Feels like an option, do these persist after user logout?
• Use the existing Unit's object - Feels heavy, there is already a lot of logic on the unit object and for reasons I can't understand, having a centralized place feels better.

[dark edge]

Why sould heavy matter with like 5 units around?

[torpid lantern]

5 units * players on server

[dark edge]

If you said 5,000 then maybe, they could just be characters tho or whatever fits the bill the best

How many players?

[torpid lantern]

However many my server can support. Ideally 50+ but I'd be happy with 20.

Game is a "mega server" linked by dedicated servers. The more players I can get per server, the cheaper it will be.

[dark edge]

It all depends on the game design and what sort of behavior you need but I'd focus on the simulation, and getting the results of the simulation (what people see) synced up well for all players

This is completely server-authoritative right, no clientside prediction or any shenanigans?

like a strategy game

[torpid lantern]

Yeah server owns everything except cosmetics

[dark edge]

That's at least a sane idea for an indie multiplayer project, prediction makes everything 100x harder

I'd just start with some actor for your entities and maybe pivot into a more abstract version later if needed.

Like, if it was Chess, The MMO, you'd just have some tiny structs

but if you need collision, pathfinding, hit tests, etc, then it makes more sense for the game state to be more in the world.

[torpid lantern]

I'm taking a ton of inspiration from Rimworld; but "MMO". Feels like a meme wanting to make an MMO as my first game, but I'm sure as hell gonna try.

[dark edge]

Yeah i was thinking of rimworld

I'd go with some simple actor for now, maybe a Pawn.

Even Character can be ok for the first draft, depending

[torpid lantern]

I'm wanting to use GAS, I've tested using character but not pawn. Not sure if it matters.

[dark edge]

Character is just a bit heavier, you don't need all the prediction stuff if it's all happening on the server anyway

[torpid lantern]

Oh, that's super good to know.

[dark edge]

Is it effectively 2D or is there some verticality?

[torpid lantern]

3d. Is movement pathing predictive? I'll need that, if so.

[dark edge]

What do you mean by predictive?

[torpid lantern]

Good question. I don't think I understand what that word means.

[dark edge]

For my first draft I'd try getting 2 players to be able to order something based on Pawn to move around to clicked locations

Just a sphere sliding around on the navmesh

[torpid lantern]

Oh, yeah - I've got basic movement all replicated so far - but I am managing task logic out of the unit's object.

[noble sentinel]

So I made this as same logic as flashlight sync, and it worked!

thank you

Sometimes It surprises me how easy things can be if you learn what is the problem

[dark edge]

Did you try with a non-server client?

or just owning client and listen server?

I thought control rotation pitch didn't make it to other clients

[noble sentinel]

I mean one listen client and one normal client?

[dark edge]

2 normal

listen is the server

so listen + 2 clients or 2 clients on dedicated

[noble sentinel]

oh well its not working whne there is 2 clients

...

[dark edge]

make sure a non-owning non-server client sees the correct thing

yeah because control rotation is failing

[noble sentinel]

What did I wrong there?

[dark edge]

Control Rotation isn't replicated

try get base aim rotation

I think that'll give you a good pitch

but I'm not sure, the whole control rotation thing in Unreal is a cluster

[noble sentinel]

I guess base aim rotation is also not replicating

still same result

It working well on flaslights tho, whats the problem when it comes to my camera?

[dark edge]

get base aim rotation should work assuming you're driving this all with control rotation as normal

[noble sentinel]

Isnt this correct?

[dark edge]

authority?

the remote client is not authority

What are you actually trying to do?

[noble sentinel]

I watched this video before for flaslight logic so I was copying it

https://www.youtube.com/watch?v=nS8d103CTJM

It worked now when I delete authority node

[dark edge]

If you want the thing that goes across the network to be "Hey Everyone, I just Fired!"
Then:
Input -> run on server
run on server -> multicast
Multicast -> do the trace EVERYWHERE

That's a bad setup but it'll "work"

[noble sentinel]

This is what I always do

Why is it bad?

[dark edge]

Because the character will be in a different place and aiming in a different direction on all machines

and also you'll have ping lag before you see your guy shoot

making a shooter is tough as hell

That's why something like the other person's more RTS-like game can be easier, you dont' care about lag or prediction. You just see what the server sees, a bit later, thats it.

[noble sentinel]

This multiplayer part is really making making games 10x harder...

[dark edge]

more like 100x for real lol

[noble sentinel]

Like I would do thousands of thing in a day but cant solve a network problem for 3 straight days

[dark edge]

I'd say if:
Game = 1x
Multiplayer Game with no prediction or lag compensation = 10x
Multiplayer Game with prediction and lag compensation = 100x

varying by the game design

Chess wouldn't be too hard to make multiplayer

Counter Strike is mega hard to make multiplayer

[noble sentinel]

And I guess UE5 is the easiest engine for multiplayer right?

I dont want to imagine others

[noble sentinel]

More precise calculation more torture for syncing

[dark edge]

Yeah pretty much, barring something weird like trying to do multiplayer Factorio

[torpid lantern]

Keep at it Akane! I'm 3 months in and feel like things have only just now started to click.

[dark edge]

I'm 8 years in and still a noob

[noble sentinel]

I made a co op game before in like 4 months
I swear %80 of the work I did was for working on multiplayer...

[torpid lantern]

Somebody posted this visual and that helped trigger my epiphany moment: https://cedric-neukirchen.net/docs/multiplayer-compendium/framework-and-network/

[dark edge]

Yeah that's the Bible around these parts

that Venn diagram used to be my desktop background

[torpid lantern]

lol

[noble sentinel]

I really didnt have a single idea

about how this gamestate/playercontroller things

work

[dark edge]

They should have called GameMode GameController then it'd line up but old code is old code

[noble sentinel]

Im running it on server than multicast.
Is it working? Good
No? Cut content

No more replication logic from me lol

[dark edge]

But if it's state, then replicate with repnotify

[noble sentinel]

I cut %50 of my game because of replication problems

[dark edge]

You shouldn't need many multicasts

[torpid lantern]

It's on my to-do list to learn wtf repnotify is

[noble sentinel]

I remember making a door with rep notify, my only business with that. Is it really that important

[dark edge]

It fires when a replicated variable changes

So responding to state changes

[torpid lantern]

Why does it need to fire? Wouldn't people know that variable changed already?

[dark edge]

How would you know it changed unless you checked?

[torpid lantern]

🤯

[dark edge]

This lets you respond to a change instead of checking all the time

You could just Tick -> did my equipped weapon change? -> play the animation and swap stuff out

but it's better to:
Onrep_EquippedWeapon -> do the stuff for changing your weapon

[torpid lantern]

Unit takes damage >> notify everybody nearby ??

Holy shit that is cool

[dark edge]

So that can be a bit more complicated

Onrep_HP -> update health bar

[noble sentinel]

So can I use it to fire a serverside + multicast even on an actor which isnt owned by player?

Im still trying to fix that bird ragdoll replication problem for 3 days lol

[dark edge]

No, you still need a run on server event to send stuff to the server

but in your case, that event would be the shot

The bird would have a replicated bIsRagdoll

and in the onrep, you'd set it to ragdoll or not

[torpid lantern]

I suppose I haven't needed much repnotify, my GAS hooks cover most floats. But the gears are spinning now on the cool stuff I can do with it. Ty Adriel!

[dark edge]

I've tried to give GAS a shake but it hasn't been great for the designs I've cooked up

[noble sentinel]

Actually bird is dying only on server but not happening on client, and its code is too basic.

What you recommend doing here?

[torpid lantern]

Problem is in your design, don't kill birds.

[dark edge]

After the branch just set a replicated bool

in the onrep, set animation and physics mode

done

no multicasts, no run on server events

[noble sentinel]

Its a mind controlling bird so we doin an exception

[noble sentinel]

Im trying this now

RepNotify?

[dark edge]

now you have a function that's called every time it changes

so just branch on the bool and do your thing

[noble sentinel]

like this?

How I will get on rep notify node?

[dark edge]

it's a function

on the left in your functions list

[noble sentinel]

So this?

[dark edge]

you need to use the bool in here

that runs any time it changes

branch on the bool

BTW in BP it'll work server and client, in C++ you need to manually call the server version

[noble sentinel]

Sorry I didnt get that, how should I use bool here?

[dark edge]

branch

Dead? just changed, what do you want to do?

[noble sentinel]

?

[dark edge]

I'd fill out the false path too

it became not dead, what do you want to do

[noble sentinel]

Nothing

[dark edge]

I'd set the opposite of the true path but it's up to you

I'm not 100% sure if that'll run on begin play or not, idk the technicalities

[noble sentinel]

Well I guess I messed something because it still isnt working :/

[dark edge]

show your code

[dark edge]

lose the Die SV

just end at setting the bool

[noble sentinel]

It was deprecated tho

I deleted it and still same.

[dark edge]

Also use NearlyEqual not equal for floats

print the bool in the onrep

if it prints consistently then it's in whatever you're doing, maybe disconnect the animation thing

[dark edge]

Wouldn't you simulate physics when dead, and use animation BP when not dead?

Why are you simulating physics AND using anim bp

[noble sentinel]

animation bp is empty so its just stop moving

Its using an asset as default

to fly

[dark edge]

try just sim physics

what does it do

[noble sentinel]

it fly randomly with its animation asset(isnt synced btw)

[torpid lantern]

I'd also print the contents of skeletal mesh, is it the same object (the bird) for all clients or is it blank?

[dark edge]

that shouldn't matter

they should all at least drop out of the sky when shot

maybe in different places but get them all to drop first

[noble sentinel]

Well I just disabled every animation and made only ragdoll

still only works for server

interesting...

[dark edge]

did you print the onrep to make sure it's working?

[noble sentinel]

I did something like this but Im not sure thats what you mean

[dark edge]

sure, does it print true on all screens when bird is shot?

[noble sentinel]

yes I guess

only after bird dies

it wrote true

[dark edge]

so that part is working, time to figure out why it's not ragdolling

[noble sentinel]

its working for server

server player can clearly see its dead

[torpid lantern]

Wouldn't client need a "True" also?

[noble sentinel]

this photo is from client

[dark edge]

yeah the logging can be weird, hard to tell what's from what instance

is the bird replicated?

[torpid lantern]

I suppose, I would expect to see a Client: True. This to me says the client is not running this logic. But am noob.

[dark edge]

Yeah but the 2 Server: true are throwing me

something is giga fucked here

[noble sentinel]

skeletal mesh? Yes

[dark edge]

put that back to default

[noble sentinel]

It happens when I do it with 2 clients too

[dark edge]

is the bird actor itself replicated?

[torpid lantern]

Do you have a has authority up the chain somewhere?

That node gets me everytime

[dark edge]

Damage should be authority only but idk if it's enforced

[noble sentinel]

yeah

[noble sentinel]

no, I dont use that node

[dark edge]

do just BeginPlay -> has authority -> delay 1s, -> set bool to true

also print the bool on tick

[torpid lantern]

what about an (is server) somewhere it shouln't be?

[noble sentinel]

I forgot putting has authority but It worked?

Both client + client and listen + client

it worked but, why after 1 seconds and not when I hit it?

[dark edge]

and when you put authority I'm guessing it doesn't work

[noble sentinel]

trying

[dark edge]

It worked because you were setting bool independently on all machines

I don't think this bird is replicated

[noble sentinel]

yeah only works for server when I do that

[dark edge]

bird ain't replicated

show your ActorReplicates checkbox and delete the bird in the level and readd it

[noble sentinel]

Well I think I missed wrong thing

Its looks like working rn, testing a second

yeah, Its working now!
Thank you very much

[dark edge]

What was it?

Actor Replicates not checked?

[noble sentinel]

I accidentaly replicated sceneroot

:/

this little mistake tought me how to use repnotify tho, and probably will help me very much later lol

Thank you very much to both of you for your help

[torpid lantern]

You and me both! Deffs going to play with RepNotify tonight.

[dark edge]

Show this panel for the bird actor

[noble sentinel]

Yeah its working now

I accidentaly replicated scene root before...

[dark edge]

idk why that'd matter, or did you replicate the scene root and not the actor itself?

The actor needs to replicate for ANYTHING replicated to happen within it

[noble sentinel]

Yeah, I waited to see a "component replicates" tick so I missed the "Replicates" one from actor

And now I know how to use rep notify so this will probably solve lots of issues for me, thanks again

[torpid lantern]

Replace that mesh with a Seagull please.

[noble sentinel]

Its supposed to be a blue parrot sorry

And I love seagulls

[torpid lantern]

Spoken like somebody who hasn't had their sandwich stolen.

[dark edge]

When in doubt, RepNotify

[noble sentinel]

Will do!

[dark edge]

you could probably make an entire game without any multicasts, although I'd still use them for stuff like GrenadeExploded

[noble sentinel]

Nah we are throwing bagels to them here, especially while we are in Ferry.

They are cathing them mid air

[noble sentinel]

You cant understand how big enlightenment it is to learn repnotify for me lol

Literally opened a new door of possibilities

[torpid lantern]

Love it when those doors open. Everything gets a little brighter.

[noble sentinel]

I still have bad memories with door replication(3 days of search)

[torpid lantern]

I've been trying to beak down my GameLift door, but she's reinforced.

[noble sentinel]

Its 4 am here, Im going to sleep. Have a nice night/day. Thanks again for help.

[torpid lantern]

Godspeed!

[lucid badger]

Is there a way to respond to an Actor itself being replicated? i.e. when it is first spawned on the client. Or is it just beginplay for that?

It doesn't look like yo ucan do ReplicatedUsing on the actor itself

[thorn turtle]

How do you replicate an action from the client to the server, like RepNotify doesn't work, run from server doesn't work, multicast just competely stops the command from playing on clients end.

[quasi tide]

The only way clients can communciate to the server is through a server RPC

If it's not being executed, it's because you're trying to call it from somewhere that isn't its owner

[thorn turtle]

So there is no way for me to sync up actions from the client to everyone else?

like toggling visibility of a component like a light

[quasi tide]

Client asks the server to do it. Server does it through an onrep

Server RPC from the client, from something they have ownership on, and then the server changes the state through an onrep variable

[thorn turtle]

So, one last question. is an RPC and onrep possible from blueprints, like even remotely or was learning unreal bp actually a waste of time

[quasi tide]

Yes, it is absolutely possible.

[thorn turtle]

If its this it just doesn't work for me at all

[quasi tide]

Please read the network compendium in the pinned resources

[thorn turtle]

Genuinely I have, I've read through it like 5 times at this point, I even followed a tutorial exactly, down to every setting and even names of actors, functions and events and it still hasn't worked

[dark parcel]

That's totally possible in bp. I've probably read and watch about 12 times back and forth and a lot of experiment.
Once you know, it's kinda straight forward. So keep going till you get it

To toggle visibility of a component light, that should be a state behavior. You can control the behavior with a bool (on or off). Make it a repnotify
Server can just toggle the light because they are the server. For clients, they will need to send a Server RPC that change the bool and light (This only happend on server).
for the client, toggle the light on Repnotify. Once the client send server RPC and change the bool the client will get updated eventually through repnotify function.

[thorn turtle]

I'm going to screenshot this and reread it along with the documentations about RPC and RepNotify in a few days. As well as remake the Actors involved for the light toggle. I'm thinking its more than likely I've made a mistake along the way and I'm too burnt out to see it atm. Thank you for the help tho

[dark parcel]

You asked if it's a waste of time to learn bp for multiplayer, it's not a waste of time but it also depend on what you want to make.
Blueprint is very limited, for example if I were to make FPS shooter I will not do multiplayer if my tool is bp only.
You will hit a wall very quickly. something like sprinting will require to dive into cpp
Turn based game should be do-able with bp only but outside of that with multiplayer, I will suggest to use cpp/learn some cpp

[thorn turtle]

Ironically I did run into some issues at the start with things like sprinting but I managed to fix it fairly fast, its somehow the stuff the should be really simple that I'm hitting the wall on

[lucid badger]

    UFUNCTION(Server, Reliable, BlueprintCallable)
    void ServerReceiveClientDebugString(ENetRole SenderRole, const FString& ClientString);

I have this function to test RPC. It just prints to UE_LOG. It is on GameState. I made sure GameState class is correct.

When I call this function from (listen) server it works fine. However, when called from client, it does not seem to actually run on server It seems to be following the rules though. GameState replicates, no?

Oh there it is

If the RPC is being called by a client to be executed on the server, the client must own the Actor that the RPC is being called on

Client probably doesn't own gamestate?

[quasi tide]

It doesn't

[dark parcel]

It's probably not a true test that you did. You need to emulate Multiplayer with lag, there is a command you can insert to emulate lag in Pie.
When lag is introduced if there isn't any form of prediction you will get rubber banded. In real world there is no 0ms, so you might want to test your sprint in Pie with lag.
Afaik sprint will require us to change a flag in the CMC

[thorn turtle]

I get it, I honestly do. However I spent quite a bit of time learning BP, taking on learning c++ now before I even have anything playable would just demotivate me enough to drop the project. Once I've got something playable I don't mind going back and recoding it from scratch in c++

[finite goblet]

Should you trust local overlaps as trigger in multiplayer scenarios?

E,g if I ran into a trigger overlap box , should I trust that both server and client version of my character would enter the overlap in fairly short time between each other? Or position error can cause inconsistency between server or client overlap missing?

[quasi tide]

I generally only let overlaps happen on the server

In regards to triggers at least

In fact, I don't even load the triggers on the client.

[grand kestrel]

It is possible that a correction will occur on the location after it triggers resulting in false trigger
You'd need to handle it if the trigger is pertinent to gameplay

If its a volume that affects movement (eg. change in friction) then you don't need to because CMC will take care of it
And if it applies damage or unlocks an achievement then of course that would be server only

[finite goblet]

Its more about how different can server and client resting position be . IIRC the default tolerance is 3 cm?

So if I stop at location such that client is overlapping a zone overlap but server is not coz its off by just 1 cm then the client would think its inside the zone , but the on the server it wont be .

So its about how close the cmc keeps client version as opposed to server

[grand kestrel]

Well, you have UCharacterMovementComponent::NetworkNoSmoothUpdateDistance which defaults to 384.0f. That's the teleport threshold. But more delays could occur such as sending the RPC that triggers the correction or even some delta between frames, I don't think there is a number where its simply guaranteed

[lucid badger]

Can I pass pointers (to replicated Actors/their components) as parameters into RPCs? does the engine translate the pointer somehow

[late flax]

Any one know why the PlayerState would become invalid after connecting to a map via OnlineSubsystemSteam seamless server travel (Shipping Build)? I have two games setup the same exact way and one connect to the map and the other gets error "DestroySession - Invalid player state"

[cosmic crag]

Hey just out of curisoity. I have this code here in the first image that handle the pickup single item. It work on server side but without linking the final node to the break. It allows the client side to do it all at once?

[chrome bay]

Makes sense. It's just going to spam all those RPCs to the Server at once

RPC's aren't instant remember, they take time to reach the server

Be better off just "Getting" the first element and sending that instead

[vagrant grail]

@pearl fog Coming back to this (yeah 2 years later 🤣 ) I think it's not totally true what you said as I watched a video showing that if you update a replicated variable and some players that aren't in the range or left the game and / or join later it will create a desync in terms of data between the client variable and the server variable as the client didn't receive the updated value. (https://youtu.be/DsjF87NSdvo)

[pallid mesa]

Context: Editor only tool

So.. I'm in editor PIE, and I got the server world from the client and I want now to find the matching controller from mine in the server from my autonomous proxy.. I've used safe name comparison to gather it, and it works in PIE due to initialization order, however I dont like it at all!

Is there any other way to find the matching controller in the server world without breaking my neck? Been playing with netguids aswell but I need to iterate through connections... isnt there really a more straight forward way?

[fathom wadi]

Quick question, what happens with the ownership of an actor if the owner leaves the server?

[chrome bay]

Could you match them up using players' UniqueID instead? Editor net subsystem should generate unique ones AFAIK

[chrome bay]

Owner gets left as-is

[fathom wadi]

Aight ty

[pallid mesa]

That might be more convenient, you know how can i access the editor net subsystem net id?

ye its a gift from a fren of mine :) she made me in her videogame https://store.steampowered.com/app/2428800/Nom_Nom_Cozy_Forest_Caf/

buu

[chrome bay]

I think just via the Player State

through the usual online subsystem stuff

[ashen plume]

testing my game as a listen server with 2 players, and if I detach from the player controller in editor, move an actor, and then reattach, the actors revert back to where they were, but not on the client

the actor positions are different between being attached and dettached, why?

even in standalone with 2 players, being attached vs detached in from player controller in editor isn't the same

[glacial zealot]

Since GameState is already by himself replicated from server to all clients, does his variables also get replicated? Like if I have a shared inventory (array of structs) should I set it to replicates or its not needed and it's already replicated automatically (even for new comers or that needs repnotify specifically)?

[ancient adder]

I have a replicable object that registers itself in a component SubObjectsList by calling GetOwningComponent()->AddReplicatedSubObject(this, LifetimeCondition);

GetOwningComponent() is just GetTypedOuter<UActorComponent>()

The object is created inside mycomponent(as an outer) on server, But when replicated to the client its created with PlayerController as the outer

Is this how UE replication works or something wrong?

[fallow kettle]

hi!! sorry if this is the wrong thread to post this on... actually I am trying to install the ue source build but I am having trouble with building the solution and I get this error as in the image... does anyone know the fix for this

[uncut panther]

Hello there ! i have a little issue, i'm trying to display Steam Name inside a PlayerList, on unreal engine but it's only displaying my own name for each of players :
do you have an idea how can i fix that ?

[rotund badger]

this is better for #cpp
This doesn't have anything to do with multiplayer.
(Close the error list forever)

[fallow kettle]

thanks mate... I will post it there than

[fathom aspen]

You need to mark the individual vars to replicate as well if you want them to

[fathom aspen]

It's probably because the component didn't exist client-side by the time the object replicated, so it fell back to the PC

You can never know without debugging it if you're interested about it

[loud pike]

Hello, anyone would know why a locomotion that is triggered is not replicating ? and so is the character orientation ?

The BSMMWalkrun runs fine but not the combatlocomotion 😦

[quasi tide]

Because however you're updating is in combat?, isn't replicated.

Show how you update that value. In the ABP and in your character BP

[quasi tide]

ABP's don't replicate btw

[loud pike]

oh

so Am I doomed ?

[quasi tide]

No

You replicate the data from the character and the ABP reads from it locally

So you'd mark Lock on Engaged as replicated. Then, you'd do a server RPC to change the value. When the server changes it, it'll then be replicated to all connected clients.

[ashen plume]

follow up from my post earlier, why doesnt my listen server update itself when i make play in editor changes?

[loud pike]

Ok thanks I'll look into RPC 👌

[glacial zealot]

If I use RepNotify so that if they join after it has been already modified, they get the sharedInventory replicated from GameState to Client, I can just set it to repnotify and the onRep function leave it blank?

[fathom aspen]

Sure, but then you don't really need the property to be a repnotify

It could have been a repnotify-less and it will still replicate just fine

[loud pike]

Actually not getting anywhere here :x

[glacial zealot]

ahhhh, I thoight replicates didnt send information on login, only repNotify

im dumb, repNotify is used to run something based on that replication, like door open, usual examples

I even knew that but somehow got confused

[fathom aspen]

No no, repnotify just adds this extra notification callback just in case you need to do something in response

[glacial zealot]

thanks

[loud pike]

Lol I think it did something wrong

[dark parcel]

you prob need to set replicate condition to skip owner

[noble sentinel]

Can anybody tell me is there any way to fix this issue without detaching spotlight from camera? Im trying to replicate flaslight pitch, it works ok when spotlight isnt attached to camera, but when its attached to camera, spotlight isnt following the camera and going too slow or too fast.

[loud pike]

If anyone has the problem I just ended up using gameplay tags ... And works great since they are auto replicated

[glad robin]

So my golf game has optional online coop. Currently I have everything set up using AGameMode and AGameState because of the networking but is there really any reason/benefit from making a second one with just AGameModeBase and AGameStateBase or should I just use the one set up for networking for both single and multiplayer as it works so far. I am probably just over worrying about optimization but was pretty unsure.

[spiral crystal]

Its fine, you could use base instead as long as you don't need the additional functionalities of the non Base classes

Optimization wise it's basically nothing, maybe some bytes memory allocation.

[sinful tree]

Nothing is "Auto Replicated".

[glacial zealot]

I used the Steam Advanced Sessions, when I create the session on Standalone from main menu, when the level gets created seems that even though the character is created I cant control it, if I open the level standalone in the game level itself I can use it...

In order PlayerController Image, MainMenu Image

Fixed somehow doing this:

but why is that even needed to restart the player, shouldn't the Agamemode manage the spawn by himself like it does on normal standalone? its the matchmaking based one

[proven grove]

Good morning everyone. I am looking for a way to assign an unique ID to my players with the purpose for my backend to be able to identify them individually. I created a replicated "ServerID" variable inside my PlayerController blueprint so the clients are not able to modify the replicated variable and fake their identity, but every time I change the value of the variable from the client, it seems to replicate to the server too, which in my understanding shouldn't happen, or I am missing something. Any help would be appreciated, thanks!

[graceful flame]

How do you plan on distributing your game once it’s ready? Steam? Epic games store? Both of those have uuid already.

[sonic cedar]

Hello !
I wanted to know if you know someone or yourself to teach me multiplayer on UE5 because I can't find anything good on ytb or google the only things I find are on UE4 😦
So if you know anything about it you can mp me or mention me 🙂
Thanks a lot

[graceful flame]

Check out the pinned messages in this channel for some great resources and if you still need some support you can always #hire-a-freelancer or even #hire-a-studio if you’d like. Also feel free to ask any multiplayer question in this channel and someone who knows might be hanging around to read it and reply.

[proven grove]

None of them, I am doing everything from scratch with no intention to ship the game but for fun/learning purposes mostly.

[sonic cedar]

The pinned messages is on UE4 :/

[graceful flame]

Which one? There’s lots

Also ue 4 multiplayer is basically the same as ue5 because iris isn’t even out of experimental yet

[sonic cedar]

So a tutorial on ue4 would work on ue5?

[dark edge]

It's all the same, just start with getting a door to open for everyone and with zero bugs

[sonic cedar]

Because I found this playlist on ytb and it's on ue4 (I'm Belgian so it's normal if it's in French).
https://www.youtube.com/watch?v=bGvaa1hpNnE&list=PLKs9b0VUdRdwNPPoPMBBMYs2TwWn-OPfe

[dark edge]

UE5 is just like a new patch of a game. It's still the same game, just a tiny bit different. The fundamentals are the same.

Dota 2 is still Dota, even though the number went up

[sonic cedar]

ok tank you a lot of !

[proven grove]

It finally works as intended when I check the "Play as Client" box, changes made on the client doesn't replicate to the server, guess I was testing as Listen-Server 😅

[dark parcel]

Only way for client to communicate with server is Server RPC.
Replication only works from server to client

[spice gorge]

What's the standard way of destroying a session?
I have a set up where the host player calls DestroySession() and they get pushed back to a default level, however the connected players just sit in the dead session thinking they're still connected. Do I have to write code to message all connected clients and get them to call DestroySession() themselves?

[spice gorge]

Actually I see that the client player's level does change. It's the same level but they seem to reload and spawn again. I guess I'll try and find an event to hook into and see if I can resolve their state with it.

[solar stirrup]

Destroy session when you return to the main menu

[spice gorge]

We don't have a main menu. Players host others in their personal level, and when kicked, return to their own version of that level. I guess that means I need to implement a destroy call when loading into that. Doesn't seem right though.
I'm tracking the SessionStatus and I expected that after the host destroys the session the SessionStatus would broadcast "Destroying", "Ended", or "NoSession". Instead it reads "Pending", which by the docs means /** Session has been asked to start (may take time due to communication with backend) */ makes me think that clients, though connected, are not getting the right updates or I'm missunderstanding how the SessionStatus works and it's not for clients to track.

[thin stratus]

@spice gorge a session can additionally be started

You might have never done that so the client would remain on pending

However the part of destroying the session would be up to the client

Sessions are just entries into the local NameSessions array

[glacial zealot]

I read all docs but I still have some issues understanding, GameMode defines the rules, GameState keeps informations about the game, and its all understood, but for example generating a game ending mission like required items to finish the game must be a funcition/event in gamemode and then sets requirements in gamestate so that the players can see that? Also when required items are added somehow you send through gamestate a request to gamemode to check if the mission is finished or its done directly on gamestate?

[thin stratus]

@glacial zealot You don't have to follow that kind of setup. The only rule there is, is that the GameMode is not available on Clients.

You can totally ignore the GameMode and perform stuff in the GameState on Server Side

The whole Rules stuff is so beginners have somewhat of an idea what it could be used for

You have to remember that the engine is heavily inspired and used for UT/Shooter Games

Where a GameMode makes total sense

[glacial zealot]

Yeah I was "scared" of maybe learning a way to do things that wasn't the right in all contexts

[twin juniper]

So replication is the progress server send down information to clients to copy, but the progress clients send up information to server is not replication?

[glacial zealot]

thanks tho

[thin stratus]

No

Client to Server goes through RPCs

Replication is usually referring to properties

And those only go from server to client

@glacial zealot no worries. A mission system could very well live in some actor component on the GameState for overall progress and with some additional component on the PlayerState for per player tracking

Depends on what you need

But you really don't have to use the Game mode for rules and stuff

It's just a general advice and example

It does make sense to put server only code into the game mode

But it's not the biggest deal if you just do it in the gamestate or similar if needed

[twin juniper]

Oh so when you mark something as replicated, it only change 1 side from server to client, but still need RPCs to pass up information from clients?

[thin stratus]

If we say rules we usually mean how many kills to win the round

Typical shooter stuff

Lots of games can make 0 sense out of that

[glacial zealot]

I dont actually store items on playerstate, I thought about that but then since players die and drop stuff I realized I just can keep track on character, that was also the thing I was scared of that maybe was better to keep on playerstate the player items and if player dies get playerstate and drop them but that seemt overcomplicated

[thin stratus]

@glacial zealot Character vs PlayerState is exactly that trade off

Character if you destroy it loses all info

[glacial zealot]

Yeah I keep persistent data

[thin stratus]

PlayerState keeps it but you'd need to clean it up if you need to

[glacial zealot]

thanks a lot 🙂

[thin stratus]

No worries

[thin stratus]

Did you read the compendium?

Cause I would mainly be repeating what I already wrote there

[twin juniper]

yeah but i still dont get it somehow

imma just try to code some example

[glacial zealot]

As I understood it @twin juniper players need to tell server what they do, and they can do that with RPCs so if players wants to say I interacted calls an event on Server to say "hey I want to interact with that", the server then manages what happens:

• Multicasts maybe to all players a sound of the interaction
• Runs on Owning Client, so calls that event on the client that owns the actor where the event is called
• Etc...

Replicating variables means that if the player attacks a enemy that has 100 health and tells server "hey attack him and deal 10" if the variable of the health on enemy is not replicated the enemy on server has 90 but on all clients have 100 health still

it's keeping in sync we can say.
Watchout tho, replicating a variable like doorOpen boolean for a door logic doesnt mean that any player can see it open, there's relevancy so far players can't replicate everything (too much memory) and so when they come close the variable is set if replicated but the door is still close, so you can use RepNotify to decide "when I get the replicated variable I want to run some logic about it?" in this case you could on the repnotify check if doorOpen is true, open the door visually etc...
Remember server if is a client always have all relevant so all is refreshed, otherwise players sending information on server to open a door that isnt loaded on server wouldn't work

You can also set an actor to Replicate on Class Defaults or also be Always Relevant so you can see players always even in the other part of the map

never used sequences to be honest, im a bit behind in animations, but as I know anim blueprint should be replicated already if Im not wrong

[twin juniper]

yeah there is no document about replicating ABP

[sinful tree]

Player Controller is only available on the server and the owning client. This means other clients can't access the data stored on them, so if your ABP is reading from the player controller to get that value, other clients won't be able to get the values as the player controller its reading from doesn't exist on their end. Use the Pawn to replicate that value and have the ABP read from there,

[twin juniper]

I also printed the direction in the screen, and it's the same in both client and server

[twin juniper]

yeah but i was playing on Listen server, so that suppose to work, no?

[sinful tree]

No.

[twin juniper]

but how did it print in the screen then

[sinful tree]

Data is only replicated from server > clients. So if you want other clients to receive the value, it has to be on something that exists on all clients.

The server has to be the one that replicates the data to clients as well.

So if you're only changing it on the client, then the server doesn't know about it, and that means the other clients don't know about it.

[twin juniper]

yeah but the animations should play in the server, even if its not playing in other clients. My case didnt even play in the server

[sinful tree]

But it's not because you're probably only setting that value on the client making the moves.

[twin juniper]

But if it print the number then it know about it?

[sinful tree]

It's not telling the server the movement or the server isn't determining the movement itself to replicate to others.

This value here... If you're reading this in the ABP from the PlayerController, again, that means only the owning client (and possibly the server) will have the correct value.
If whatever is determining this value is only being calculated on the client and not the server, then only the instance that is calculating that value would be the one seeing the animation.

[dark parcel]

ABP just reads value from it's owner. Much like widget

[sinful tree]

Truth be told, you probably just need something that determines velocity vs. actor forward vector and it should be getting calculated on clients locally, nothing need be replicated as it already is being replicated if you're using the CMC.

[twin juniper]

Or print is just not a good method to check?

[sinful tree]

When you are seeing "Client 0" that is in literal reference to the same game instance even though it is printing that on separate windows.

[twin juniper]

oh shi

[sinful tree]

So it's printing the same value on both windows and the source of that print is from one instance of the game, namely client 0.

[twin juniper]

then how do i check if the server knows?

if not print

[sinful tree]

You can print while running on the server

The places where you see "Server:" is where the server is executing the print

[twin juniper]

Oh, that make sense, let me try that

i am bamboozled by unreal print bruh

[heady copper]

Any voice chat guide? On best practices for implementing voice chat in a multiplayer game?

[buoyant jacinth]

Any idea on how to replicate a ragdolls location?

Right now on one client it is on one place, and in another client, on another location.

[glacial zealot]

Setting a Event Dispatcher to Replicates or RepNotify is used for something?

[lost inlet]

You generally don't (can't) replicate delegates/event dispatchers

Makes little sense to do so

[twin juniper]

I have this setup on my character BP, it gonna print twice, because i am using Listen Server with 2 players. How do i make it print only once, on the iterate through the "host" s BP, not the guest?

You know, like instead of a check "Has Authority", do we have "Is Host" or something like that?

[latent nest]

I think maybe if you use like getting the player controller or soemthing along the lines of that and gettting index 0 possibly

If I’m understanding it correctly

Idk

[twin juniper]

Yeah get controller and check if the index is 0. But how to check though?

Some text format stuff?

That's be quite weird i guess.

[latent nest]

Idk I’m not home right now otherwise I could check. I think if you just get player controller though and cast through that you could because the server is normally index 0. I could be wrong but it’s just something to try out

[unkempt tiger]

I'm seeing that Epic decided to end the online session inside AGameSession::HandleMatchHasEnded, does this mean that sessions are not supposed to persist across different matches?

[twin juniper]

Better if there is some information about how print work

They work quite randomly to me

[mellow thorn]

Does one need to replicate variables set via OnConstruction in C++ or the Construction Script in BP? It doesn't seem like it to me, but wanted to make sure...

[fathom aspen]

Not necessarily since those events run server and client side

[mellow thorn]

Does that mean if you set a variable with a random int or float that variable will be different on client vs server?

[fathom aspen]

yup can potentially be

[mellow thorn]

Thanks for the info

[south skiff]

Is there a way to make animation blueprints deterministic? For example have a current time variable which I can scrub through manually (potentially backwards)?

I'm trying to implement snapshot interpolation and animation is the only thing that doesn't make sense yet.

I know in Valorant they did it by rewriting parts of the animation graph to be able to evaluate it on demand, but I'm looking for an easier approach by using limited anim blueprints.

[coral locust]

Got a question, wondering if its possible to hand the server over to another client if the server disconnects. Hope this makes sense? Would love feedback on what people may have. Or ideas around this.

Like is there a way to switch host while ingame?

So before server disconnects then switching hosts.

Okay so I am seeing its called Host Migration . Anyone know of a solution for this in ue5?

[glacial zealot]

it prints on each window, it says Server if that print is from server, client if its from client

[sinful tree]

There is no built in solution for this in UE.

There's a paid plugin on the marketplace that apparently offers this kind of functionality, but it's likely to be extremely inefficient networking wise, as every client would need to have a copy of the state of the game, so that means all values of all objects has to exit on all clients all the time for this to work correctly.

[coral locust]

Yeah, I am seeing this. Any thoughts on another solution or idea on what else could be done. Other then dedicated server

Maybe a partial system. Like if the player disconnects unexpectingly then it would not migrate. But if the player leaves via a in game menu, then it would store everything it needs to run the game and choose another host? Would this be possible? If so what all would need to be done to make this work?

[sinful tree]

Not a suggestion, but one way to work it would be to completely ditch Unreal's networking system entirely and create a P2P networking system to use in Unreal. I have no idea what that would entail, but you would lose out on all multiplayer features built in to the engine.

One could potentially do as you describe, but it wouldn't be something that would be instantaneous and it would be a lot of work to set up. Again, not sure on what would actually be required myself but it woudl be something like the server would need to choose new host, send all the data about everything to the client to become the host, store that data in Game Instance, create a new session, open the map, reinstate everything where it should be and somehow communicate that back to the server that has the clients so that they can then migrate to the new host, while keeping the game "paused" in some way until all clients rejoin the new host.

[dark edge]

Assuming all clients have enough state to recreate the game then that's doable, idk how they'd find each other though, that's OSS / beacon territory

but it wouldnt be that hard to save some cores state every x seconds and have some protocol for choosing a new client to host in the event of the current host leaving

would not be seamless though, not at all

[latent basin]

I have seen people multi cast the ragdoll each frame but its seems silly, if you find a solution pls let me know also

[coral locust]

That’s okay. Would you be familiar with how to build something like that?

[dark edge]

Think about what you actually care about

That might be as simple as just syncing the pelvis location

[whole iron]

Anyone know why me walking into another player while crouched launches them? Using Zippy Character/Character Controller
Walking into them normally when uncrouched does nothing/doesn't launch them

[umbral patio]

Does unreal have any plugin for lag compensation in shooter games?

[hollow eagle]

ACharacter movement is already lag-compensated. If you're asking about rollback for firing then no, that's up to you to implement.

[umbral patio]

aha, ok

[wanton bear]

if im trying to sync a projectile to look correct while hitting an AI i.e. client 1 and client 2 see the bullet hit at the same location on the AI.

So client 1 shoots and i'd want to sync up the bullet forward in time to where it should be on the server and then send that to client 2 because the AI would be behind as much as the bullet because they're also controlled by the server?

[spiral crystal]

Does someone know if the order of entries in an replicated TArray is reliable? or can the order vary from server to client? (i guess not, but i ask anyway 😄 )

[fossil spoke]

Never rely on order of a replicated TArray.

[spiral crystal]

ah god damned

ok thanks

[fossil spoke]

It is not retained

Across the network

If you need "order", just pack your data in a struct with some identifier you can use to sort it.

[spiral crystal]

It's a struct already, okay cool, thanks!

[south skiff]

Anyone?

[dark edge]

#animation

Probably not though, not easily anyway

MAYBE if you get a synced clock and use that to feed all looping anims

What's the non-deterministic part you're encountering?

Anything with a loop has to be fed its time, not just played

[south skiff]

Well as far as I understand all animations tick locally, so if I simply interpolate movement and let anim do its thing it will desync. I'm thinking about attaching hitboxes to bones, so I need it as close as possible

[dark edge]

Yeah you'll have to have them use a synced clock, not just the local clock