multiplayer

[quiet rapids]

Don't use this approach. Use OnReps and check the doc first

https://docs.unrealengine.com/4.26/en-US/InteractiveExperiences/Networking/Actors/ReplicatingVariables/

Check this not the previous one

[shrewd dawn]

oh so I should set it replicated on server then multicast collisions?

[quiet rapids]

#multiplayer message

[shrewd dawn]

Alright thanks but I still want to get it working using this method

first before I try learning the other one

[fathom aspen]

To get something working the incorrect way is a bad habit

[dark edge]

If it's a state, use repnotify. This sure sounds like state to me.

You would repnotify MyStaticMesh. You would multicast PlayExplosionFX

[fathom aspen]

Yes you should be able to. Travel with ?listen

If an OSS is implemented, such as Steam then yes

If not, then no. It's done by IP addresses which is bad, but good enough for fast testing

Yes. That's why you got IsNetRelevantFor. Override it and use that state in there

[summer hemlock]

Thanks, I will give it a try!

[fervent gorge]

u mean, as long as ip doesn't change - controllers netID will remain the same regardless even if i restart game?

and as i can suggest, the one who gives netID - online subsystem?

[fathom aspen]

Yes

[fathom aspen]

NetId is given by an OSS. Even if you restart the game it's still the same.

If multiple players are playing with the same remote IP address, the wrong player could take over another disconnected player on their network which is not the correct way to handle disconnects

But I don't see a shipping game without an OSS

[fervent gorge]

is it safer to use playerState's name?

[fathom aspen]

It's safer but still a bad habit. The only unique identifier you should be using is the NetId

Look at AGameMode::AddInactivePlayer for reference

You should be overriding that if you want a different behavior

[fervent gorge]

okay, thank you

[kindred widget]

NetID are safe because the OSS has access to identifiers that are truly unique for specific accounts. For example. NetID for a Steam user is their Steam ID number.

[fervent gorge]

🤔

so working with steam - netID is not depend on IP

[kindred widget]

Not sure what Null uses. I don't know what Epic's are, but I know Steam's are your Steam account ID number. Epic likely has a similar number per account, just less visible.

[fervent gorge]

got it, thanks

[clear island]

can someone clarify something for me about multicast RPCs

I assumed when you call a multicast rpc, the code inside that RPC function is executed on the server aswell as all client machines

but the behavior I'm getting, is that the code is only being called on the server

it executes for all clients on the server, but not on the actual client machine

[kindred widget]

A Multicast should only ever be ran on a server version of a replicated object. And then yes it should run on every machine that object is replicated to. If you run it on the server on a non replicated object, it will only run on server. Likewise if you run it on client on either a replicated or non replicated object, it will only run on that client.

[clear island]

thanks for clarifying, I think I found my issue

I was sending a multicast RPC on BeginPlay of a replicated actor

but none of the clients were getting it

I guess RPC's on BeginPlay event are a bad idea

probably too soon

[kindred widget]

Your RPC likely reached client before the server had a chance to replicate the object to client.

[clear island]

makes sense

when is the best time to send an rpc to the clients?

I mean I can add a timer to delay it

but

seems dirty

I want to send it as soon as clients are "ready" to receive it

[kindred widget]

There likely is no surefire way. If you need a sure RPC, multicast probably isn't what you're looking for. What is your usecase for it?

[clear island]

oh is that so? If I add "Reliable" to the multicast would that not cover it?

my usecase is as follows:

• player joins server and sends his nickame (sent as an option ?NickName=etc...)
• server receives the nickname in GameMode::PosLogin and stores it in the PlayerController
• then the character of the player is spawned on the server during beginPlay, I was sending a multicast rpc to all players letting them know the nickname of the player that just joined

[kindred widget]

Not really. The issue is design theory. Mutlicasts are usually for one time things that server needs to dictate that aren't stateful. For the same thing that is stateful you use a replicated property. The reason for this is because you cannot promise timing to clients. One client can get the RPC up to 250ms after another client. One client might connect after the RPC, and never get it and be missing the required state.

I honestly don't have a lot of usecases for good multicast use. Simplified chats maybe, where you don't have to care if new joiners see the old chat.

[clear island]

I was using the beginPlay event on the server to check when new players join, but thats just too soon I guess

[kindred widget]

If you want a one time initialization of something, you can make client tell server that it's ready, and pingpong Server/Client RPCs reliably back and forth to init something. But generally speaking replication is usually the best case in a ton of scenarios.

[clear island]

I tried doing that at first but ran into other issues

because I was calling an RPC from a simulated proxy which unreal does not allow

[kindred widget]

For your use. That generally sounds like a single Server RPC to send the nickname. PlayerState can store the name and broadcast it both on Beginplay or OnRep of the property. Just check if it's a valid non empty name before broadcast. That'll cover pretty much all cases.

[clear island]

well the thing is, I'm not sending the nickname of the player that just joined to himself, infact, I need to send it to everyone but himself, so other players will see his name

[kindred widget]

Well, no, that would break.

[clear island]

thats why I thought about a multicast; new player joins, send his nickname to all other players

[kindred widget]

New players would see every join immediately with that. I guess you could Client RPC loop to all controllers except the one the name is for.

[clear island]

yea I want players to see when a new player joins

[kindred widget]

Would likely break for new game, but any player who joins after 2+ seconds would be seen by everyone already connected.

[clear island]

oh that is interesting, I didnt know I could loop through all the controllers on the server

how can I do that? using c++

[kindred widget]

From GameMode?

Also ue4/ue5?

[clear island]

ah you mean, on the GameMode::PostLogin, store the Playercontroller on a list/map of a sort?

UE5

ah wait now that I think about it GetAllActorsOfClass function might work I guess 🤔

[kindred widget]

Nah. Sec

[clear island]

for now delaying this multicast with a timer fixes my issue but I'm trying look for a cleaner solution, would be nice if unreal had some sort of event that could tell me when a client is "ready" (has been replicated) so I dont send RPCs too soon

[kindred widget]

for (APlayerState* PlayerState : GameState.Get()->PlayerArray)
{
    APlayerController* LoopController = PlayerState ? Cast<APlayerController>(PlayerState->GetOwner()) : nullptr;
    if (IsValid(LoopController))
    {
        LoopController->MyClientRPC();
    }
}

Replace APlayerController classes with your controller type that has the RPC.

And you can add a != check for the one you don't want to RPC

[clear island]

ahh I see GameState holds a player array

[kindred widget]

You can always access every player's Pawn, Controller or PlayerState through that. PlayerState's Owner is the associated controller, and Playerstate has a PawnPrivate property to their connected pawn.

[clear island]

I haven't gotten that far yet as to create my own GameState class, still in the early stages, but will get to it soon

[kindred widget]

You don't need to. It's default framework.

Just need the controller with the RPC, everything else is already in place.

[clear island]

yea I know theres a default instance of it but I will need to create one eventually too since I need to store some stuff specific to my game's state, but good to know that regardless

[clear island]

about this, do you know if theres some event that will tell me when the client has been replicated? it would be useful also for other stuff not related to this issue

would this do it? https://docs.unrealengine.com/4.26/en-US/API/Runtime/Engine/GameFramework/AActor/PostNetInit/

[kindred widget]

That I'm not sure on. I've never had a case where I had to care about that. 😄

[clear island]

I see, I'm gonna give it a try and see whats called first, this or beginPlay thanks for the help anyway 👍

[fathom aspen]

The first place it's safe to call RPCs on PlayerController is OnPostLogin

If that was your question

[fathom aspen]

Client has been replicated

That's not a meaningful statement

Actor has been replicated to client

That's the one

BeginPlay SwitchHasAuthority Remote Pin

[clear island]

I am calling some RPCs there already but not this one, this one when the player character spawns on the server( when that character's beginPlay is called)

[clear island]

yea when the actor has been replicated to client

[fathom aspen]

Yeah pretty much BeginPlay but using that authority macro with the remote pin

[clear island]

hmm but that still will get called during beginPlay, no?

[fathom aspen]

If you have a reference to that spawned actor where it's replicated then you can have it as an OnRep

[fathom aspen]

BeginPlay is called on both server and client

[clear island]

yea I know but only the server knows the player's nicknames

so the server needs to send it to players

[fathom aspen]

It doesn't get called on client without it being replicated

[clear island]

yea I know but its replicated

and it still doesnt get called on clients

[fathom aspen]

Nickname is something that would be stored in the PlayerState

[clear island]

unless I delay it with a timer instead of doing it immediately on BeginPlay

[fathom aspen]

And would be replicated

As I said you know an actor has replicated to a client using the two ways I already mentioned

[clear island]

I thought about that but I think replicating something that would never change (like the nickname) may not be the best thing to do

[fathom aspen]

Whatever you are describing is being something particular to your setup

[clear island]

I need to know from the server, when the client has been fully replicated

during BeginPlay seems to be too soon

[fathom aspen]

It does actually. What If a new player joins late?

[clear island]

so I was wondering if theres another event after that

[fathom aspen]

RPCs aren't stateful

Also that replicates like one time

As long as it's not changing it won't be replicating

[clear island]

ohh I see

hmm maybe replicating really might be the best option

[fathom aspen]

Again you're saying statement that doesn't make any sense. A client isn't an object. Objects replicate. Clients don't

[clear island]

sorry, when I say "client" I mean the player character

which is an Actor I believe

[fathom aspen]

Yeah that makes sense

Correct

What you're describing is a classic problem where its solution is a replicated property stored in the PlayerState

[clear island]

yea I think you're right

[kindred widget]

I have a vague memory that there is a system in place for this already.

Sec. Testing some stuff with an overridden character component and I'll see if I can't find it.

[clear island]

I've noticed the playercontroller has a GetName() and SetName() functions if thats what you mean, but I haven't had any success overriding those values

[kindred widget]

This was still for the introduction stuff, right?

[clear island]

what do you mean?

I first get the nickname on GameMode::PostLogin

[kindred widget]

@clear island Ah. I thought I remembered that right. APlayerState has a playername. The Onrep for that calls HandleWelcomeMessage(). HandleWelcomeMessage broadcasts a localized Text along with the playerstate in question. Which can be bound to things like chatboxes, or HUD class for popups, etc.

[clear island]

ahh I see, that might just be what I need then

[kindred widget]

This all basically starts at AGameModeBase InitNewPlayer, which calls ChangeName, Which calls SetPlayerName on the PlayerState. You could easily override InitNewPlayer, and copy the rest but leave that ChangeName line out until your client sends their name and call ChangeName then. I think it'll work about the same.

[clear island]

interesting, I'm gonna look into it, thanks!

[grizzled stirrup]

When using Clientside CMC movement, it seems Pawn->GetVelocity(); is incorrect on the server even though it's moving at the correct speed

Is there a way to retrieve the correct velocity that the client is actually at?

It's about 3x less than it should be on the server so it's quite a significant difference

[ebon lily]

I might do a multiplayer gamejam but I haven't done anything in mutiplayer with UE, would that be time consuming?

there isn't much gameplay it in

guess it would have to be peer to peer

[fathom aspen]

There is no p2p in Unreal. The most close configuration to that is called listen-server

And yes this isn't going to be a 1+1=2

It takes time to get your head around Unreal's networking

Here's the starter pack: #multiplayer message

[dark edge]

yes

I mean go for it

but it'll be 5x harder than you think

[vivid dagger]

anyone using playfab for backend have a clue on how to reduce stacks from online inventory properly? using ConsumeItem is limited to just 1 item instance so it would stack up a lot of api calls

[ebon lily]

guessing I can't have it done in a few days? lol What I want to do is have one player place objects together, then the other player would have to do something to those objects.

[vivid dagger]

you can do it in a few days if you drink a couple of energy drinks on the way and listen to some nightcore songs on 2x speed

[dark edge]

If you think of an idea you could whip up in an hour, you could prolly do it MP. If you already knew how the MP works, it'd be a lot easier.

[clear island]

are all PlayerStates and their Pawns() available in all clients?

[ebon lily]

I understand some of it from doing a multiplayer tut a while back, really just duplicating code and making everything replicate lol

[topaz knot]

Question: When I try and connect over the internet it doesn't work but it does work on my LAN, using Epic. I've tested it a few ways. How do I trouble shoot this? I've trying checking LAN on off on both join/create session.

[dark edge]

Disregarding relevency yeah

[fathom aspen]

By default: PlayerStates are always relevant, pawns are not

Also there are other cases where it's not

It's not only relevancy

[clear island]

I mean from inside a PlayerState I can do: GetPawn(), is that pawn available even for simulated proxies on the client?

[fathom aspen]

Could be it taking time to replicate PlayerState at start

[dark edge]

It's not NOT availible, but it could be on the other side of the world and thus not in relevency range

What are you trying to do?

[fathom aspen]

Yes, unless the pawn is destroyed or not relevant

[clear island]

I see

not doing anything in specific at the moment, just trying to plan my next steps

[vagrant grail]

I need to make an inventory for my multiplayer game, how would I do that ? Should I follow any tutorial about inventories ? What should I replicate and what should I not replicate ? Any good advice about how to do it ? I need to go for a Minecraft Like inventory.

[fathom aspen]

Use this channel search. You should be seeing too many examples, tips, ideas, etc.

Also don't follow tuts, YT ones especially

[vagrant grail]

I watched alot of them and everyone of them felt weird to me and looked wrong to me the way they do it and also most of them aren't the type of inventories I'm looking for. Most of them make RPG inventories style with some slots being specific to some objects (like potions, weapons,...) and most of them didn't have a hotbar

[uneven chasm]

if i have a run on server event are all events triggered from that event downstream server only as well ?

[vagrant grail]

What should I type in the search bar, isn't there any other resource teaching how to do an inventory system compatible with multiplayer ?

[quasi tide]

All of my inventories are just arrays really.

[fathom aspen]

Are you sure?

[sinful tree]

All a standard "slot based" inventory is, is usually a replicated array.
The multiplayer aspect of it is only just a matter of handling how the client interacts with the server's copy of the array without letting the client tell the server what is in any particular slot.
Eg. You don't let the client say "I am moving a Ultra Rare Powerful Item in slot 1 to slot 2" but instead just tell the server "Move the item that is in slot 1 to slot 2".

[fathom aspen]

Start from this @vagrant grail , build up

[vagrant grail]

like should all inventories (of all players) be replicated to all players ? Like I think players will be able to cheat if they can see what each person has in its inventory

[quasi tide]

Only replicate what is needed.

[fathom aspen]

If they get executed then yes

[quasi tide]

No reason for player B to know about Player A's inventory if they're not interacting with it.

[vagrant grail]

That's too vague for me 😦

[sinful tree]

Do people need to see everyone's inventory all the time?

[quasi tide]

How is it too vague? If player B is not interacting with player A's inventory, should they still get the data sent to them?

[vagrant grail]

Nope

[quasi tide]

There you go. Then it is not needed.

[rotund sail]

i mean unless they can trade, should they ever interact with one anothers inventories?

[quasi tide]

Often times, I just replicate the inventory to the owner.

[sinful tree]

More than likely not. I'd have a third container to handle the trades where players present what they want to the other player.

[vagrant grail]

There will be a way to trade stuff in a place but it will be through a graphic interface with slots and both sides need to confirm the trade after putting the items

[rotund sail]

ye or you can drop-trade if you have droppable items

[fathom aspen]

You can't change replication condition at runtime anyways

[vagrant grail]

but people could throw items from their inventory to the ground like in Minecraft

and if another player goes on top of it he gets it

Should the inventory be its own actor that I add to players or I can do that directly on the BP_Character ?

[sinful tree]

Do a component. That way you can add it to other things as well.... Like storage chests.

[fathom aspen]

Ok it seems like it's a thing. I remember seeing this in this past, had to look it up: RESET_REPLIFETIME_CONDITION 😄

Though I won't change it

[vagrant grail]

Could someone give me a first step to laucnh my self because I'm stuck on what to start with. Like if I do the UI first is it a good step ?

[fathom aspen]

I would have a basic UI just for testing and focus on getting the prototype done

[fathom aspen]

This is my advice, and ah a note too

[clear island]

so about this, I've been doing some testing and it seems when I do GetPawn() inside the PlayerState of simulated proxy, it will return null unlesss I'm doing it on the first player that joined the server, in that case its not null for some reason

and it is relevant btw (both players are right next to each other)

so the conclusion i reached is that GetPawn() inside a PlayerState of a simulated proxy can return null at times, even if that proxy is relevant

[fathom aspen]

Your conclusion is simply wrong

Send code so we see what's going on

[clear island]

ok, so on GameMode::PostLogin I'm getting my player nickname and storing it inside the PlayerController

then, on my Character (Actor) I'm polling during tick for when the playerState becomes available on the server

that is on the server, you can see I'm getting the nickanem from my playercontroller and storing it on the PlayerState Nickname variable

that variable is replicated

[fathom aspen]

What all this has to do with GetPawn?

Ah ok finally!

[clear island]

it never enters that SetNameTagText block of the code

keeps saying its null for some reason

but only for the second player

for the first player it works just fine

I'm also using a dedicated server btw, if that matters

so basically my process is:

• open server
• open game client1 and join server
• open game client2 and join server
• client1 sees client client2's nickname
• client2 does not see client1 nickname

[fathom aspen]

Okay that's normal

You are trying to get the pawn on client which gets set when APawn::OnRep_PlayerState gets called. What if PlayerState hasn't replicated for that pawn @clear island

You are doing it too early so it hasn't been replicated yet

[clear island]

I thought about that but then I tried adding a 3 second delay to that last line CharPlayerState->Nickname = PlayerController->PlayerName; but the issue still happens

I used a timer

[fathom aspen]

You shouldn't be doing delays anyways

[clear island]

yea it was just to test

[fathom aspen]

That's not how you solve it

[fathom aspen]

Take this and see how you're going to fix it. I don't see anything particular about your setup. It's literally a game with OnReps

[clear island]

what I find strange is that the PlayerState itself is not null, but the Pawn is

I dont understand how such a thing could be possible, PlayerState is related to the pawn itself as I understand so I dont get it

I'm not using OnRep_PlayerState btw

that poll I'm doing is during tick

on the server

[fathom aspen]

That's not something I would do

OnRep is there just for that

[clear island]

such as: when its available on the server I set the replicated "Nickname" property because its the server that has that information

[fathom aspen]

I wouldn't even have a NickName on PlayerController

Would have it only on PlayerState

[clear island]

the only reason I have it on PlayerController is because that is what I get in GameMode::InitNewPlayer

the playerState itself sometimes is null during that event

so I chose to store it on the PlayerController

and then tried to pass it on to the playerState with that poll

I dont think I can use OnRep_PlayerState because that is called on the client and the client doesnt have the name of the player that joined

[fathom aspen]

Would probably have as part of a LocalPlayer subsystem. But yeah that should do the trick too

[clear island]

to give more context, what I'm trying to do is just some nametags above players' heads

[fathom aspen]

Ok then why you're doing it in Character?

Why not PlayerController?

[clear island]

the nametag widget is part of the character

[fathom aspen]

There's where PlayerState gets spawned on server

[fathom aspen]

Good. There's a property already in PlayerState called PlayerName which is replicated and all.

Inside Character I would wait till OnRep_PlayerState is called, and in there I would pull that name and set it as the name for the nametag

As easy as that

[clear island]

yea tried that too 😄

[fathom aspen]

That works

With eyes closed I can make it and guarantee it works like a charm

[clear island]

its the same issue though

[fathom aspen]

It's not the same issue

[clear island]

during On_RepPlayerName I have to get the pawn too

and at that point, its null again

[fathom aspen]

You are literally using all classes to get something really simple done

Don't overcomplicate

[fathom aspen]

Again why do you need the pawn?

[clear island]

well 2 classes atleast I need which is my character (which has the widget) and the PlayerController which has the name I received in GameMode::InitNewPlayer

because the widget is attached to the pawn

[fathom aspen]

Ok then do it inside the pawn

You see that there is no event that guarantee you the pawn is there

Why are you determined you wanna make it work that way

[fathom aspen]

Plan B

[clear island]

actually I tried to using just the pawn first, but I had some issues too a few days ago, but tbh I dont even remember what those were, so I guess I'm going to try going that route again and see what happens

meh, still no luck

I tried this on the Pawn

then on the server as soon as I have the player controller:

this sets the replicated Nickname property which is inside the pawn

then on the client:

[lost inlet]

there's something triggering about On_RepNickname rather than OnRep_Nickname

also the playerstate is not 1:1 with the character

[clear island]

not too worried about naming at this point 😄

[lost inlet]

it is with the controller, in fact the controller owns the player state

[clear island]

hmm I see

[lost inlet]

also you can't guarantee replication order of actors

the character/pawn does not own the playerstate

you can possess different pawns during the course of a multiplayer match

[candid gale]

#cpp message

Putting this here, I don't think my question belonged to cpp

[lost inlet]

You don't need to implement subobject replication for components, this is done for you

[candid gale]

So the character part is redundant I assume?

[worthy knot]

MP question : Is it better to possess a vehicle pawn or have your character control it without possessing it?

[clear island]

so I finally achieved my goal doing it all from the pawn only with the code I posted above, and I now notice where it was failing

this variable was null, apparently this UWidgetComponent::GetUserWidgetObject() function returns null during the first few seconds on the simulated proxies for some reason

the overheadwidget variable itself was not null but the userwidgetobject returned by that function was

need to poll for it

I already knew about playerstate, gamestate being null for the first few seconds but this one was new to me

[quiet rapids]

Possess it. Also you can't add movement input unless you are the owner.

[worthy knot]

yeah but what if i want to shoot while im driving? all the ammo info / weapons is stored in my player inventory.

if i possess it i cant do any of that

[quiet rapids]

When you want to shoot while driving, un possess the vehicle and re possess your character and then you can have a shooting state in the server which will move the vehicle in the last velocity direction before un possessing.

[quiet rapids]

Well technically you can keep the character possessed all time and do vehicle movement through rpc to server but you might seem some lag in that case.

[quiet rapids]

Or a better way if you want to do turns while shooting is, posses the character when shooting and only during that duration, you can control vehicle through server rpcs, minimizing the lag times.

[worthy knot]

in gta online the player character never actually possesses the vehicles, and have all the freedom to shoot or throw items from their inventory, i want it to be like that

[quiet rapids]

.

[winged badger]

as long as your vehicle movement component is not tightly coupled with the PlayerController

all you need to do is SetOwner of the vehicle to get RPCs to work

and push the vehicle's input component on the PC's input stack

[worthy knot]

and how would i know if im doing the RPC's correctly or not

[winged badger]

you don't have "No owning connection for..." warning spam in your output log

only problem with above approach is that engine has a bug with input masking

and i think it affects EnhancedInput as well as old input system

basically, if your first component on stack has something bound to say W, and lower priority component has Shift+W

higher priority IC consumes the Shift+W input and lower priority one doesn't work then

it is just a few lines of code to fix the engine there though

@worthy knot

[grizzled stirrup]

@chrome bay Just re-read your article on OnRep weapon firing counters. Just curious if you were designing a basic replicated weapon today, is it fine to do stuff like this (muzzle flash / fire anim) with unreliable Multicast RPCs rather than OnRep vars?

Reason being is that in general OnRep stuff seems to be stateful

Whereas Multicast RPCs are nicely one shot and transient

Or is the benefit that you don't want loads of multicast RPCs being sent for fast firing weapons, rather the latest OnRep value which will only trigger the FX once?

[hoary nova]

arent multicast rpcs super costly?

[grizzled stirrup]

I'm not sure about super costly, in what way? Bandwidth?

[hoary nova]

I always thought of rpcs as top priority messages sent across, is it really necessary to use them for stuff like visuals?

[grizzled stirrup]

That's why the Unreliable tag is there

For things that aren't top priority

[hoary nova]

Oh I see, I haven't used that yet. I guess I'll have to look into it

[worthy knot]

damn doctor, i need to know more about all this

[chrome bay]

The burst method is stateful by design, because third-party clients in my case need to know whether the weapon is still firing when the receive burst info. This is so they can keep ticking the firing simulation and avoid stuttering/jitter by getting multicasts and/or property updates at variable times. Whether a shot was fired at all, and whether it's still firing is packed into the same property. If you do this with a multicast, you can't guarantee that the "stop" fire event will reach them.

Unreliable Multicasts go down the same network path as property updates btw, so they too are prioritised, respect net update frequency etc - but the point here is the burst counter is replicating both a state and an "event".

Automatic/high ROF weapons for instance will keep ticking the firing sim so long as bFiring is still true, and will trigger at least one sim if the burst increments once.

That's not clear in the article though, I should add that

Also, sending unreliable's means you can potentially fill the buffer up with RPC's, instead of just a single property update. Property updates are gathered at the end of the network frame, whereas RPC's are dumped into the buffer when you call them. You could throttle other properties/RPC's by doing this

[grizzled stirrup]

Thank you very much for the explanation!

Makes total sense now

[dim trail]

how should multiplayer cooldowns be done? if theres a low cd on an ability, potentially there could be huge dps variance because of lag

[latent heart]

You can always have the client request to re-use the ability while it's in cooldown.

I believe WoW had a kind of "do this thing next" if it was used close enough to the end of the current action / cooldown wearing off.

[dim trail]

wow uses a queueing system

but its fairly complex

any client side solutions are hackable

[latent heart]

I haven't played it in 10 years Shrug

[latent heart]

One would assume so?

[latent heart]

Sounds like the components are not replicating their activated status.

If they were replicating their status, they'd be spinning and moving properly!

You might try destroying the actor and creating a new projectile, as if the bat was actually a gun that destroyed itself when it fired. But that seems overkill.

[graceful flame]

I’m doing something similar with my projectiles. I have a client side only “fake” projectile that spawns and triggers sfx and vxf while waiting on the server to spawn the real projectile. This reduces the feeling of lag for the shooter, but I’m now dealing with double sound because of the multicast firing projectile effect meant for other clients is also happening for the shooter.

[latent heart]

Pass the shooter with the multicast delegate and have it ignore itself?

[graceful flame]

I managed to enable Owner No See and it works for the mesh but can’t get the last part working so I don’t hear the sound

So the shooter actor? Controller?

Maybe just pass the net id of the shooter?

[latent heart]

Pass the character reference

It will be converted to a netid automatically and converted back on the other end.

Or the Instigator reference, I suppose.

[graceful flame]

Ohhh what?????

That’s good to know

[latent heart]

You can pass any replicated object to an rpc and it will work fine.

[graceful flame]

I always thought it would be this huge character object that would eat up a ton of bandwidth

[latent heart]

If it was replicated directly, that is. Subobjects that aren't components, probably not.

[graceful flame]

This changes…..EVERYTHING!

https://tenor.com/view/the-universe-tim-and-eric-mind-blown-mind-blown-meme-mind-explosion-mind-explosion-meme-gif-18002878

[latent heart]

...what have you been doing so far?

[dark edge]

You're just passing an ID that gets converted to a pointer or something. It's tiny.

If I text you my address, I don't actually send you my entire house. I just tell you how to find it.

[graceful flame]

Yea I understand how that compresses things but I didn’t realize that was happening in the first place. Makes sense now though.

[latent heart]

If you don't know that, though, Adriel, it makes sense to think that the entire object is sent, like it is with structs.

[frank phoenix]

Is there a way to disable the client to join the dedicated server when testing in editor? Working on login system and dont want to waste time on compiling

[woeful ferry]

Is there a collective name for classes that client "owns" like PlayerState, PlayerController, APawn?

Need it for a function I'm writing so it's not long as hell

[latent heart]

Not really.

[dark edge]

Turn off auto connect to server

But you're better off just launching

[woeful ferry]

shidd

[dark edge]

you can make bat files to launch a client and server

[latent heart]

Maybe ClientAutonomousActors?

[woeful ferry]

Sounds good! 😄

[frank phoenix]

seems that this option was removed in UE5, cant find it in editor preferences

[pliant moss]

Okay this is a bit weird. I run a function on the server to spawn an actor (with an ASC). in the same function i set a gameplay tag on the actor. Now the weird part. If i use AddReplicatedLooseGameplayTag(GameplayTag) The tag only activates on the client simulated proxy. But if i use AddLooseGameplayTag(GameplayTag) it only shows on the servers actor instance. (that does make sens since its not replicated) but why does AddReplicatedLooseGameplayTag only applies to the client and not the server?

[limber gyro]

hey guys, im having a bit of an issue with a shot registering twice on the clients and only once on the server(which is what is suposed to be happening in the clients)

what i am doing is basicly a raycast, and if it hits the mob i subtract HP from the mob

the HP variable is replicated

[pliant moss]

My MP experience is quite limited. but did you try to only run the HP substraction on the server?

[limber gyro]

it also only does this weird behaviour the first time the mob is hit

[limber gyro]

that would be my first guess too but im doing something similar with characters and it works fine

[fathom aspen]

How about you post some code?

The related stuff

[limber gyro]

sure

                AProjectArenaEnemy* enemy = Cast<AProjectArenaEnemy>(results.Actor);

                if(enemy)
                { 
                    enemy->HP -= damage;
                    BulletOwner->hitNotify = true;
                }
                else//if its not an enemy or a player than its the world
                {
                    if (hitDecal)
                    {
                        FRotator rotator = FRotationMatrix::MakeFromZ(results.ImpactNormal).Rotator();
                        GetWorld()->SpawnActor<AActor>(hitDecal, results.Location, rotator);
                        UE_LOG(LogTemp, Warning, TEXT("decal spawned"));
                    }
                }    
            }```

so i do a raycast and it checks if the resulting actor is a anemy

and i just subtract the hp

{

    Super::GetLifetimeReplicatedProps(OutLifetimeProps);

    DOREPLIFETIME(AProjectArenaEnemy, HP);
    

}```

this is just the replicated var

its counted twice on the first hit in the clients but its fine in the server

[fathom aspen]

This doesn't tell me much

What calls this stuff

Get me into the whole picture

[limber gyro]

i spawn an actor which has the raycast

the actor spawns, raycasts, then dies

do u want the spawn code or the whole raycast code?

[fathom aspen]

I want all the code since the moment you shoot the shot to the moment you apply that damage/health decrease

I want to see RPCs

Functions

Authority checks

[limber gyro]

gimme a sec let me setup a pastebin

[fathom aspen]

Provide people with the full context so they can help you. Else you're just shrugging at this server and we're too

[limber gyro]

https://pastebin.com/13FJkeHV

ok so this is the character that shoots the projectile, i only copied the relevant parts

the whole "shoot" chain

https://pastebin.com/vY52D8c5

this is the hitscan bullet

any ideas?

it was an authority thing like @pliant moss said

i had missed

[latent heart]

Little tip, directly setting things like health leave you open to refactoring code later on. You should use setters, then you can respond to events and check inputs and the like.

Your SetHealth function could check if it's enough for the player to die and kill them, for instance.

[pliant moss]

isnt this going to run on both the server and the client? BulletOwner->hitNotify = true;

[limber gyro]

i know, its just testing for now, on the characters i have a proper "receivedamage" function

[latent heart]

Alrighty! 🙂

[limber gyro]

i think so, but i left it that way in case theres lag in the network so that the player gets the hit confirmation regardless

from a game design perspective it feels better

[pliant moss]

Yeah, and i forgot the word for it but the server needs to correct the client if the client is "wrong". there is built in functionality for that in the Character i think (Prediction is called i think)

[fathom aspen]

Ok so you are doing this inside a tick function. Do you know it's executed on both server and client?

I couldn't tell where you're doing it because the code in the second file looks weird

Your best gamble here is literally to debug and see where it's breaking

[limber gyro]

i already fixed the issue, it should be executed in both places but i got a authority check so it only executes in the server, i had it in begin play i think but i was having some issues that i cant remember and switched it to tick

with a gate

and the issues got fixed, now im just being lazy and i dont want to move/search to/for a better function

[wheat magnet]

does player remain remain alive when open new level? or it reset?

[fathom aspen]

Pawns gets destroyed and recreated upon traveling

[wheat magnet]

i have main menu game mode, where player select character before joining server. when game starts, it open new level. but i want to get variable values from old level

so game instance?

because it is multiplayer

[fathom aspen]

If I had my article done by this moment...sigh

[fathom aspen]

That's like one way

You've got PlayerState with a function called CopyProperties

You can use programming subsystems

[wheat magnet]

i have two game modes. one game mode is for main menu, and other is for gameplay

[fathom aspen]

Though this only works in seamless travel

[wheat magnet]

but player state is same in both game modes

so when i again open new level with different game mode, does player state reset?

[fathom aspen]

It doesn't have to be same. Shared variables can be in a parent PlayerState where two different PlayerStates inherit from

[fathom aspen]

Almost everything does by default

Upon seamless and non seamless traveling

Though you have a very short period of time where you can copy properties from the old instance of the player state to the new one

Same goes for PlayerController. OnSwapPlayerControllers

So my TLDR is this

If you are seamless traveling: use CopyProperties inside PlayerState
If you are hard traveling: use GameInstance/Subsystems/SaveGames

[dark edge]

You could just have sub-levels right? Or streaming levels or whatever

Our game is procedural so we don't do any loading ever beyond initial startup

Can't you just have your pawn etc in the persistent level then swap out levels under it?

[fathom aspen]

Yeah that could work too if you got sublevels

[winged badger]

you can just not spawn the Pawn until your spawnpoints are in place too

[wheat magnet]

player is possessed but not moving

this is only happened when i open this map from main menu map by selecting map

but when i open this map manually in editor and run game, input works just fine

what could be problem?

this is how i am opening this map

game mode is also set correctly

[fathom aspen]

btw does this mean I can persist same reference of pawn to the destination level: #multiplayer message ?

I thought this function is used to persist client-only actors as it's called on client

[fathom aspen]

#multiplayer message

[wheat magnet]

great i already fixed using this.

[fathom aspen]

Sometimes answers are one search away

[pale hazel]

Hi, I got a problem with Multicasts being ignored by clients after the first time

I have a multicast that's fired when a character is possessed by a controller (in the ACharacter::PossessedBy method), which happens after they spawn, the multicast is responsible for giving them the correct material, depending on their team ID (stored in playerstate)

This works fine in round one, but from round two and onwards, when new characters are spawned using the same logic, the multicast is executed on the listenserver, but not on the connected clients. So on the listen server all characters have the correct color, but on the clients they all have the same, default color

So the multicast executes normally in the first round, but after that the clients never receive it

[fathom aspen]

https://vorixo.github.io/devtricks/stateful-events-multiplayer/

[pale hazel]

Yeah I saw this when I looked through this chat, and it seems useful for late joining, but in my case all playercontrollers are in the session when it happens, I'm not switching maps, controllers, or anything

The most confusing thing is that it consistently works the very first time I spawn characters and send the multicast. it only stops working after that.

[fathom aspen]

Even if you don't allow late joining, multicasts were not designed for this

Whatever you're doing is stateful and that needs replication

[pale hazel]

I suppose you're right, I'll see what I can do

[fathom aspen]

Also you are calling it early on which there is a very high possibility where it could not get executed. The first point where you can get RPCs to work reliably is PostLogin

Though at that point the pawn should be possessed and all, still I wouldn't take the risk

[short arrow]

Why even RPC this? Why not use an integer repnotify to determine which color to set each player?

Seems like exactly what you'd use a repnotify for

[pale hazel]

You're right for sure, frankly it's been written like that for a few months and always worked, which is why noone in our team touched it

Only recently these Multicast calls started behaving like this, and now here I am trying to clean all this up

[short arrow]

@pale hazel Definitely switch over to repnotify for anything that has to be called when relevancy becomes apparent

[pale hazel]

I will and see if that works out, thanks

[rotund onyx]

How am I supposed to be changing levels in multiplayer? I have a lobby and a destination map. Just using Open Level disconnects everyone. I see stuff on ServerTravel but I don't know if that is the solution and I am having trouble figuring out how to use it

[latent heart]

seamless travel

[fathom aspen]

ExecuteConsoleCommand function and Command parameter be ServerTravel <MapName>

Can only be called from server

[rotund onyx]

Should I do that with seamless travel or without?

[fathom aspen]

Either way all clients will follow server. Though the preferred way to travel is seamless

[rotund onyx]

do I need ?listen as part of the command?

[fathom aspen]

Nope. That only if you want to make a player host a map, so he's a listen server

[rotund onyx]

seems like clients just stay in the lobby, any idea why that could be?

[fathom aspen]

My wild guess as I don't see code: You are calling ServerTravel from client

[rotund onyx]

that is in the GameState

maybe I should move it somewhere else?

[fathom aspen]

Oh shit

This is your lucky day: #multiplayer message

You can't call server RPCs in actors not owned by client, i.e GameState

Read that compendium fast

[rotund onyx]

that link doesnt work

[fathom aspen]

@thin stratus help!!! Your website is down

[fathom aspen]

Let me send you my copy

rofl

Here you go

[rotund onyx]

its been down for awhile

[fathom aspen]

Multiplayer support is back

[rotund onyx]

otherwise I would be using it lol

[fathom aspen]

Always download. There has been rumors that the internet is going to be down for a while soon

For example I have Laura's blog downloaded for offline use

Just in case I wake up and not find it

[rotund onyx]

well at least I have one now

I was using GameState so that all players could easily see which maps were selected, so I thought I could load a map out of it seeing as it was the server

guess I'll move that into the gamemode

[fathom aspen]

Well if you want some shared info placeholder that isn't specific to a player that's almost GameState

GameMode won't let you do RPCs too

[rotund onyx]

then how am I supposed to load a map as the server, lol?

I just need the server to take clients with it

[fathom aspen]

Literally make sure you are on server and do that ServerTravel

In my Character class

Can be either in Character, PlayerController

Doesn't really matter

This is the correct version

I don't know what triggers a server travel in your case. But in my case it's a key press which is client side generally, so I RPC to server

[rotund onyx]

its just a UI for me

[fathom aspen]

Ok that's client side too

[rotund onyx]

I am confused as to why my other RPCs work though. Things like map previews do seem to update correctly for clients. I was routing those through GameState too

[fathom aspen]

You need to let client side controller which is the owner of your UMG that you clicked that UI button so it triggers an RPC inside the PlayerController which does the servertravel

[fathom aspen]

They just don't

You were faked into thinking they do

[rotund onyx]

I have a multicast in the gamestate that was clearly working

[fathom aspen]

That works

[rotund onyx]

what can the gamestate do?

[fathom aspen]

Did I say it doesn't?

I said you can't server RPC

[rotund onyx]

ok clearly I dont understand what RPC means

what does it mean?

[fathom aspen]

"too" here was a bit misleading. It's still correct though

[fathom aspen]

It's written in that compendium

[weak osprey]

So sorry to interject; I have what I hope is a quick question.

I created a multiplayer VR game in JS, using websockets, and it was insane, and I never want to do that again, lol.

I'm wondering what the easiest possible way to get started making a multiplayer situation in ue5 is? (with blueprints)

Is it to just literally work through the docs?

Or, should I go the other way around and hack Lyra?

[fathom aspen]

A lot of stuff. Server RPCs is just none of them

[quasi tide]

If you don't know UE, don't start with Lyra. Because the networking bible site is down currently 😭, use this: #multiplayer message

[graceful flame]

Lyra is too complex when you’re starting out imo

[fathom aspen]

I feel blessed everyone's using my copy now

[graceful flame]

There’s other far more basic multiplayer templates out there

[weak osprey]

I've built 3 games in ue5

[twilit radish]

I was just about to say, did no one make a copy?

xD

[rotund onyx]

but the compendium lists Run on Server, Run on Owning Client, and Multicast as RPCs
You are telling me that isnt true

[graceful flame]

Ahh okay

[weak osprey]

but none of them are multiplayer.

[rotund onyx]

so clearly I am misinterpreting the document

[quasi tide]

Okay cool. That link is still your new bible.

[weak osprey]

word.

OK, and it applies to ue5 I'm assuming

[twilit radish]

Just read this for RPCs honestly: https://docs.unrealengine.com/4.27/en-US/InteractiveExperiences/Networking/Actors/RPCs/

[quasi tide]

Yes

[weak osprey]

got it

[fathom aspen]

What did I tell you as not true?

I just don't get it

[weak osprey]

what about the idea of buying a kind of pre-set up networking system on the marketplace; is that a way to just get up and go with it?

[quasi tide]

Sure

Quality is up in the air obviously

[weak osprey]

is there any that people use here?

and feel good about

[fathom aspen]

They are all RPCs. GameState can only call Multicast RPCs, not the other types

[quasi tide]

Pretty sure like everyone just does their own because it's so darn easy in UE

[rotund onyx]

ok THAT is what I was wondering

[weak osprey]

oh ok

[graceful flame]

Well multiplayer is just replicating all the actors and properties that need to be replicated across the network for all clients to see properly. The server remains the authority and can be either a player (listen server), meaning someone “hosts a game” for others to connect to, OR you use a dedicated (headless) server which is just a terminal running somewhere on Amazon server or something.

[weak osprey]

that's cool to know

[rotund onyx]

not sure why you couldnt just say so lol

[fathom aspen]

GameMode can't call any as it's not replicated

[quasi tide]

There are some stuff that makes using the subsystems easier, yes

[rotund onyx]

that makes sense too

[weak osprey]

alright, I guess I'll use the compendium and give it a shot, and if I start crying I'll come back lol

[rotund onyx]

you will cry

[weak osprey]

😦

[rotund onyx]

the nature of multiplayer is such

[twilit radish]

This video is also awesome btw: https://www.youtube.com/watch?v=JOJP0CvpB8w

[quasi tide]

A thousand times that

Yes yes yes.

[rotund onyx]

the blueprints arent actually complicated, but the concepts and little rules are what kills me

[twilit radish]

I mean that's just multiplayer in a nut shell, no one who knows what they are talking about ever said it was easy haha

Only if we could just get rid of latency and cheaters 😔

[graceful flame]

The biggest thing to understand when it comes to multiplayer is that there’s only really one true instance of the game running and it’s the server who runs the real game. All the connected clients are simulating the game world locally and simulating the movement of other player’s characters as the server sends out packets along the network.

[quasi tide]

Friggin' light speed is too slow, am I right? 😅

[twilit radish]

😛

Or dedicated servers actually being affordable for small teams / games. That would also be very cool.

[graceful flame]

So when you’re playing your favourite online game and there’s lag spikes which cause your character to stutter and rubberband all over the place, what’s happening is that the server and client disagree with where the current player’s location is. Since the server is the authority (to prevent cheating) it issues a movement correction teleport and the result is what players usually call lag.

[stiff nebula]

imo for cheaters

if your game is casual ive noticed that in games with a smaller playerbase they lack a cheater problem if theres a vote kick system in place

ive not seen a single cheater in quake live / diabotical / dirty bomb

[twilit radish]

If it's a PvP game and it gets big enough cheaters are almost always unavoidable.

[graceful flame]

or if there’s a way to farm gold and then turn around a sell gold for real money, then you’ll find lots of cheaters too

[stiff nebula]

true, riots anti cheat is really great and ive still seen about 4 hackers

though i think all got banned

[twilit radish]

The one big game I'm aware of that is PvP and doesn't have cheats in the main concept of the game is Rocket League.

[stiff nebula]

oh yeah, cant really do many traditional cheats in that game

[twilit radish]

In the regular game modes all you can do is find exploits in theory. But this obviously isn't viable for like any other game xD

It just happens to be nice for RL haha

[dark edge]

They are, if your game design works with community servers. Think Valheim or GarrysMod or Minecraft

[twilit radish]

Well yes, but I was referring to hosting them your self.

[dark edge]

Yeah that's pretty much a no go unless you got money.

[rotund onyx]

how does one set values in the PlayerState?

[fathom aspen]

Like you would set in any other class

[rotund onyx]

basically I want clients to pick a color, and I dont know the order of events to actually get that choice over to the PlayerState

I assume it is owned by the server

[fathom aspen]

It's not

It's client owned

It's spawned on the server though

[fathom aspen]

BeginPlay of PlayerState is a good entry point

[rotund onyx]

I have a separate issue where the server is getting a duplicate UI, I dont remember how I fixed that last time

I thought having a function that just constructs the ui on owning client would work but it doesnt

[fathom aspen]

HUD is generally the class that constructs widgets

[sinful tree]

If you do things on Begin Play for the player controller, it executes on the server (the host!) and the client's end. So it's calling that function twice as your server is telling the client to run it and the client is also running begin play themselves.

You need to use HasAuthority or IsServer checks.

[rotund onyx]

how can I force just the owning client to run it?

does it even need to be a replicated function then?

[sinful tree]

Probably not, unless you want the client to wait for data to be replicated before creating the UI.

[rotund onyx]

ah good to know

[sinful tree]

Even then, perhaps not an RPC to do it.

[rotund onyx]

if I do this

wouldnt the server never make its own UI?

[sinful tree]

Correct.

[rotund onyx]

so how can I just make it once for everyone?

I can't believe this is so hard

[sinful tree]

Well if this is player controller, you could probably do IsLocalPlayerController

Then only when true create the UI (if you only want it created on the local controller)

[stray thunder]

If I change game modes, do the player states stay the same?

[fathom aspen]

#multiplayer message

[rotund onyx]

no, but you can grab the Event CopyProperties to move over data

[fathom aspen]

What do you mean by widget? UMG or 3d widget component?

Ok UMG is client only, so each player will have his own UMG widget

Though they can share the data and both widgets can pull from that data source

[rotund onyx]

recreate or just update it on all clients

[fathom aspen]

Yeah there should be some sort of interaction with the server. Clients can't talk to each other directly

Especially that local PlayerControllers don't know about each other

[clear island]

quick question about organization in code, how do you guys organize your code to account for delayed initialization of components? things like playerstate, gamestate, controller and sometimes widgets take a few seconds to fully initialize so I poll for it during tick, but once you get to a point where you have many of these variables that can have delayed initialization, things start getting quite messy,when polling for so many stuff, so I'm just curious how do you guys do it?

[fathom aspen]

PostInitializeComponents

[clear island]

does that guarantee that playerstate, controller, gamestate and stuff will all be ready at that point?

[latent heart]

Neverrrrrrrrr

[fathom aspen]

It's per actor and it guarantees that components have been initialized

[fathom aspen]

There is no global function that guarantees all those have been initialized

[clear island]

yea thats why I use poll during tick

but the code is growing out of control

with so many variables

so just wondering how other people do it

[fathom aspen]

If you mean guarantee that it replicated then that's another story we had last night

Use OnReps

If you mean initialized on server then you have to know the order of actors creation

[clear island]

yea for clients, I'm relying onReps to detect that

there's things however that are initialized but not 100% ready sometimes

as I discovered last night, for instance UWidgetComponents will be initialized because I'm creating it on the constructor of my actor

but, it wont be ready

not immediately atleast

[fathom aspen]

I'm not sure what ready means

[clear island]

when I do UWidgetComponent::GetUserWidgetObject()

that will return null for the first few seconds

so thats just another case where I'm polling for it during tick

whenever that returns something other than null, then I have a boolean that tells me bWidgetIsReady

its these delayed initializations I'm talking about

but after a while having to create a boolean for every case like that gets messy

it works, but its not very organized

I suppose theres no other way around it, not a big problem anyway

[fathom aspen]

You literally said what your issue was. The component has to be there as I said, though that widget isn't

This function is what you need

This what calls it

Like literally it's a matter of discovering the source code

Also you never access a pointer without checking if it's null

[latent heart]

The check and what you do on the result of that check are important, too.

Silently failing null checks are super bad.

[clear island]

my issue yesterday was that my nickname onrep was being called before my widget had been fully initialized (despite being created on the constructor), the widget itself was not nulltpr but when trying to get its userwidgetobejct with GetUserWidgetObject() it returned null for the first few seconds, but yea I wasn't aware of that update function, I think thats what I need, thanks

[clear island]

yea thats why it took me so long to find the issue, I was doing null checks so I never really crashed but I wasnt doing any logging on those checks

[fathom aspen]

There's a good chance that this is what you need:

Play around with it. See what calls what

[clear island]

hmm yea, gonna have to try, I wonder if I can call it during the constructor

the fact thats its not called by default makes me think I cant

[fathom aspen]

You don't call it. You should be able to bind a delegate to it so it's called when it gets executed

[clear island]

oh I see

gonna look into that

[worn wagon]

Anyone successfully used PlayerController->SetIgnoreMoveInput in multiplayer? When being run on the server it works for the host but not clients. I'm looking for a way to "freeze" a player in multiplayer, the only way I have found to work is by setting the movement mode on the character pawn's movement component Char->GetCharacterMovement()->SetMovementMode(EMovementMode::MOVE_None); But I'm hoping there's a different way, this doesn't feel like the "correct" way of doing it to me.

[fathom aspen]

I know no other way but this

Oh and StopMovementImmediately iirc

[worn wagon]

That's the function I use when my players die, but there's no "StartMovement" function, at least not that I can find

How would I reverse it?

[fathom aspen]

Yeah you're right it's only when players die. I would also probably try SetInputModeUIOnly

[worn wagon]

That's clientside though, you could cheat out of that. Not that cheating is a major concern for my game, but there's gotta be a serverside way of doing it.

I guess I'll stick with movement mode

I just don't get why SetIgnoreMoveInput doesn't work on the clients, or what the point of the MovementState is either. I also tried MovementState.bCanWalk = false, which didn't work.

[fathom aspen]

CMC is a nightmare

[fathom aspen]

Stick to the traditions

[worn wagon]

I mean if that's what everyone is doing then sure 😅

[bitter swift]

After declaring an RPC call, I noticed there are two ways of calling it. You can call the Funciton as the name is declared OR you can call the Function_Implementation().
Does calling the implementation mean that it only runs locally?

[fathom aspen]

Correct

[latent heart]

In the current module I'm writing, I'm using I think 2-3 actual nullptr if blocks, the rest are check(). I've traced down errors extremely quickly.

(in 280 odd files.)

[clear island]

I really need to get into the habit of using that more often

[rotund onyx]

ok I still can't get my levels to load on both client and server

you'd think it would be simple but somehow this is hard

[fossil spoke]

@rotund onyx Does your GameMode have bSeamlessTravel enabled?

[rotund onyx]

no

[fossil spoke]

Probably should do that

[rotund onyx]

I need different gamemodes and player controllers though

[fossil spoke]

Ok?

Enable it on all your GameModes...

[rotund onyx]

no I mean like I dont want the gamemode to persist because I need to use a different one

same for player controllers

[fossil spoke]

The GameMode wont persist if the level your moving to has a different one.

[rotund onyx]

I just need clients to not disconnect

[fossil spoke]

bSeamlessTravel specifically fixes that.

[fathom aspen]

He literally told you how to do it

[fossil spoke]

Keep in mind that SeamlessTravel does not work in the Editor.

[rotund onyx]

I'm just reading the list of persisting actors from that compendium and trying to figure out how it works

[fathom aspen]

It will anytime soon

[fossil spoke]

It probably forgets to mention thats only the case if they are the same type.

[rotund onyx]

ah conveniently omitted

[fathom aspen]

Even if they are the same type, for example GameMode. Runtime data won't persist

It persists to the transition level by default

Not destination

[fossil spoke]

There are a lot of nuances to Seamless Travel.

Its difficult to understand until you understand it lol

[fathom aspen]

Yeah it's really. I started writing a post like a month ago and I can't finish it xD

20min+ read time lol

[languid cobalt]

Anyone able to explain why set actor rotation through a server->multicast only works when the server executes vs when the clients execute?

When the above code executes for the server, it rotates for everybody. When the code executes on the clients, they only rotate locally and neither the sever or other clients can see the rotation

Pretty much using the base ThirdPersonCharacter. I don't recall changing any CharacterMovement settings

[shell forum]

I thought the same thing when I first implemented it. Both the GameMode and PlayerController will change to the new level’s. The only thing that truly persists are widgets.

[rotund onyx]

now thats an interesting tidbit, I guess I need to remove my widgets after loading levels for once

[quiet rapids]

This might help https://youtu.be/h3A8qVb2VFk

[quiet rapids]

To call a server rpc from client, you must be owner of that actor.

[thin stratus]

Thanks. That happens every now and then. Shitty Wordpress...

[thin stratus]

To be fair, chunk loader is more for loading the pre-packaged game from a server if you have no distribution

That was mostly useful for Mobile

Where you couldn't (still can't?) upload big APK files

So you upload a small one and download the remaining chunks ingame.

[rotund onyx]

I would love to know if you find a way to do this. So far I have found no way that doesn't require port forwarding. You will not be able to directly replicate assets, partly because UE won't do it natively, partly because they will be much too large to simply replicate by checking a box.

[quiet rapids]

I just saw he mentioned about post client build.

My bad.

[rotund onyx]

I do know steam lets you download and use workshop items at runtime, maybe that can be a way around the issue if you don't find a better way

I'm still trying to figure out my thing from earlier. I want players to pick some simple settings (just represented as strings in my project) before joining a multiplayer lobby, but I don't know how to get them loaded properly.
Someone said to store them in a config and load it after getting into the game but atm all it does is load it on everyone's playerstate and obviously I don't want that. The replication of this has gone totally over my head and I could use an example if anyone has got one

[thin stratus]

Should be back online, thanks for reporting!

[unique sparrow]

Also the console have the following errors
MyStaticArray: illegal qualified name in member declaration
type cast: truncation from const int32* to int32

[fossil spoke]

@unique sparrow Use a TArray<int32> ?

[unique sparrow]

So I can use regular tarrays without changing their size right?

[fossil spoke]

Well pushmodel doesnt support array replication anyway.

[unique sparrow]

Really?

[fossil spoke]

It treats it with normal replication rules

[unique sparrow]

Isn't this macro for that use case only?

[fossil spoke]

Unless its changed Im pretty sure its not supported.

It maybe WIP still 🤷

Unless you can find an example in Engine Code i doubt its actually usable.

You may want to look at FastArrays

[unique sparrow]

They don't maintain order 😦

Maybe I should try with Tarrays?

[fossil spoke]

FastArrays are similar to what you want with PushModel

[unique sparrow]

Yes but I need order to be maintained

[fossil spoke]

Then your out of luck.

[unique sparrow]

Should have worked though🤔

[fossil spoke]

🤷

Never used it, didnt know it existed.

Doubtful it works.

Or there is something missing from the explanation of how to use it.

[unique sparrow]

I guess that is the case

[quiet rapids]

Use DOREPLIFETIME_WITH_PARAMS_FAST_STATIC_ARRAY

They should have updated the example though

[unique sparrow]

Oh wait let me check

[unique sparrow]

Ohh man.... I literally spent two hours why it won't work. Thanks a lot!!!

[faint eagle]

Is there a guaranteed order of replicating player states and game state to clients and player controllers and HUDs BeginPlay events on clients?

[iron crest]

Hello, I Have A Problem, I Have An Attack Move Set Up Where Everytime You Attack Your Character Moves A Bit, Now Im NOt Sure If I Should Use Switch Has Authority Or Just Normally Replicate The Event, It iS Being Called Through The Anim Bp Btw here Is A Screenshot Of My Bp. Everytime I Test It Either Makes Both Players Move Or No One Will Move

[quiet rapids]

No those are not guaranteed.

[quiet rapids]

Adding impulse on the server would just be fine.

You might consider adding impulse for the autonomous player too in case you see lag, but you then also need to make sure that server replicated movement don't make it jitter due to lag. Anyways just doing that on server would be all fine though.

[iron crest]

ok perfect thank you

[old yoke]

Is there a way to delay/disable new connections to a dedicated server while changing map?

[wooden cypress]

How do I get a controller from a gamemode? My kill counter variable is stored inside of a controller which I need to get to display it on the HUD

[latent heart]

If it's on a client you want to get that information, it's not possible.

[latent heart]

Game modes don't exist on clients.

You should store state information on the game state class.

Then you can use the game state's player array to get its players.

[wooden cypress]

Its per play kill counter though

[latent heart]

And, again, the states of players should be on their player state class.

[wooden cypress]

If its on state wouldnt it be conjoined with all other players instead of being each players individual kill counter

[latent heart]

It doesn't matter what it is. If you are in the game mode and are trying to feed information to a widget, this will fail in multiplayer.

It doesn't matter where the data is. It's the game mode that's the issue.

[latent heart]

You can set values to be only relevant to their owners, so they will only be sent to the owning player.

[wooden cypress]

Ok, how would I get a int variable from a controller within a function

[latent heart]

You need to get a reference to the controller.

I believe UMG widgets have a "get owning pawn" or something.

Get that, get their controller and then cast it to your player controller and get the int.

[wooden cypress]

I'm getting html Blueprint Runtime Error: "Accessed None trying to read property CallFunc_GetOwningPlayerPawn_ReturnValue". Node: Cast To BP_Controller_Mouse Graph: Get Kills Function: Get Kills Blueprint: WP_HUD

[quiet rapids]

Are you doing on tick? It is invalid when the game just begins.

You can have a valid check

[wooden cypress]

This is within my HUD get Kills function

[quiet rapids]

Are you calling this function on tick?

Or bind?

[wooden cypress]

Its onPostLogin

[latent heart]

Is that creating a widget every tick? Nvm

[quiet rapids]

That might get executed even before the player properly initialized

Why you sending a client rpc? Just do in player controller begin play

[quiet rapids]

locally

[latent heart]

To clarify, begin play is called on both server and client, so you need to make sure it's only called on the owning client's side (or on the server if it's a listen server's local player controller)

[quiet rapids]

Also do it in HUD begin play. No need of controller.

[wooden cypress]

The kills is stored in the controller

[quiet rapids]

Get controller reference from hud and pass

[quiet rapids]

I mean cast the controller to yours and then pass the kills value by accessing from it.

[wooden cypress]

How?

[quiet rapids]

There is a variable in the hud called PlayerOwner, get it and cast it to your player controller and then you can access the kill from it.

[quiet rapids]

Also HUD beginplay is only called on client so no need to do check for if the player is locally controlled.

[latent heart]

It's not called on the server which is nice, that is, if you set the hudclass in the PC.

[wooden cypress]

I think this works thanks

[flint star]

Is there a way to order OnReps?
I have 2 components on the same actor
On server I set value in comp A then value in comp B
but OnReps fire on client in wrong order
value on CompB then value on CompA

[fathom aspen]

Call an RPC back when first OnRep is called

Then set value in Comp B

[quiet rapids]

That might not be the best solution. What if the second attribute is armour which was increased, then until the rpc comes, the player will be fighting be taking damage at lower armour.

[quiet rapids]

That is a little bad design I would say where one replicated variable depends on another replicated variable. You should avoid such cases.

Maybe in some cases it might make sense but I can't think of it out of the box right now.

[flint star]

well it's very hard to untangle, they were not designed to be related, they just got related AFTER we needed a specific edgecase fixed

and I would like to avoid costly refactoring just to fix a small issue

[quiet rapids]

Are those values always set together on server?

[flint star]

not together, but in the same frame

[fathom aspen]

Yes it's wacky. Was talking in general

Also you need to call an RPC for every connection

Which also sounds weird

[quiet rapids]

If they are always set together. I mean if A value changes then B value is also changed on server, then you can have short delay on client to make sure you have updated values.

[quiet rapids]

Yes

[flint star]

I was thinking of explicitly calling multicast in the CompA, since it will arrive before the OnRep
but IDK if late join replication won't be fucked as well

[latent heart]

There's no guarantee that the updates to the values will be sent in the same frame or, indeed, anywhere near each other.

[quiet rapids]

Yep that is still the case

[latent heart]

It'd be fairly simple to set up a client-side state when the values are replicated. "ReadyToRecieve" "ReceivedA" "ReceivedB" or so.

And only trigger the functions you want when they are both done

[quiet rapids]

Yes that is a solution. Before that I would suggest if you can somehow remove this dependency. Otherwise you can go with quick fixes.

[latent heart]

Yes. That is a better solution.

[quiet rapids]

It can have gotchas in cases where - First A & B set together, works fine, then only A is set & sometimes later B & A are set together & then B reaches first then you will have the old value of A.

So better remove the dependency.

[flint star]

sure, but like I said they are not really dependant in all cases

just in 1 edgecase

so tying them together completely would lead to more issues

[quiet rapids]

If you can make sure that if value A changes, then value B also changes in server or vice versa, then do as Daekesh mentioned

[silk trench]

hi there - it might be a long shot, as the problem is with the code i have not written and don't really understand network/replication but maybe:
in NetworkPredictionServiceRegistry, when GetDataStore hits this ensure
npEnsureMsgf(ModelDef::ID > 0, TEXT("ModelDef %s has invalid ID assigned. Could be missing NP_MODEL_REGISTER."), ModelDef::GetName());
is this something simple to fix or requires the intervention of a programmer who actually wrote it/understands that?

[wooden cypress]

Why is the event AnyDamage not being triggered here when I use F?

[quiet rapids]

Have you overridden TakeDamage function somewhere?

AnyDamage is not a virtual function that you are overridding & is called from TakeDamage itself which is known as ReceiveAnyDamage in c++.

If you have overridden TakeDamage, then make sure you call ReceiveAnyDamage to get it working

[wooden cypress]

The return value of Apply damage is 0

I cant figure out why

[wooden cypress]

I deleted the anydamage event

[quiet rapids]

You use C++?

[wooden cypress]

I do not since it looks horrible

Scary

[quiet rapids]

Then I guess it should work unless you have overridden TakeDamage and not calling ReceiveAnyDamage.

Didn't saw you are calling on client. AnyDamage is only called on server

You need to apply damage on server

not on client

[wooden cypress]

I have one more ApplyDamage node but thats it

[quiet rapids]

#multiplayer message

[wooden cypress]

ApplyDamage only executes on server

[quiet rapids]

You are calling here on input F, if you are playing as client it will only run on client and not server.

[wooden cypress]

How would I force a node to execute from the server?

[quiet rapids]

This is just a note that it should be called on server.

[quiet rapids]

Custom server rpc event

call it from there

[alpine flower]

Hello, can somebody tell me what is wrong in here? Client runs "Open" but "Open" can't run "ClientOpen".

[quiet rapids]

You don't own the door so you can't send rpc

[alpine flower]

I also tried to call rpc from here to character and then open by casting to door

Client still can't do anything

[quiet rapids]

Show how you do that

[alpine flower]

sec

doing screen shots rn

door bp rn

[quiet rapids]

Seems right, did you try debugger or print statement? Which event is it not reaching?

[alpine flower]

i'll try to detect whats wrong with print and i'll tell you

[quiet rapids]

Just first make sure that custom event open door is called on client

Just add a print statement there and see if says client

[alpine flower]

fails here

[alpine flower]

it does

[quiet rapids]

Ok then check along the path whatt doesn't

Although this shouldn't be handled by multicast. Opening door is a state and should be handled via OnReps

I suggest you after fixing this to work to get a better understanding of rpcs, shift the logic using RepNotify

Otherwise when a player gets relevant later or rejoins, He will still see the door as closed

[alpine flower]

its coop game so there are two players

if one leaves lobby closese

[quiet rapids]

What if you plan to extend the game? You will have to redo all stuff.

[alpine flower]

okay i get it

[alpine flower]

still if its called from clientside it fails here

but when serverside calls it it goes further

function that gets look at actor https://blueprintue.com/blueprint/ngsg2ob7/

input action calls it

it is

components too

only interaction comp is not

Can you show it somehow? I dont get what you mean

[stray thunder]

in a multiplayer game, where do you guys attach your ui/hud?

[alpine flower]

gamemdoe

[fathom aspen]

Unless that's a multicast

That was not what I said

GameState is not client owned and you can RPC

Multicasts

You are wrong

Yes from server on GameState

You can also from client iirc but it will be local

You can be. That doesn't make it right

What? Client calls a server RPC so it executes on server

[alpine flower]

So i have to make a RepNotify boolean on interact set it to open/close (as server) and when it changes call open door in bp_door?

[chrome bay]

You can only call a Server RPC on something you own, which doesn't include the GameState

[fathom aspen]

Multicast that is called on server-side GameState is executed on server and all connected clients

[chrome bay]

Multicasts can only ever be called by the Server

A client asking the server to call a multicast is a pretty obvious security issue too

[fathom aspen]

Haha I didn't say this xD

Yes

You can call multicasts

I didn't say that

[chrome bay]

You can never multicast from a client anyway

[fathom aspen]

You said you can't call any RPC

Including multicasts

Which is wrong

[chrome bay]

Sounds like a semantics thing really. A client cannot call RPC's on a GameState. The Server can.

[fathom aspen]

Yeah that's why I said iirc it will be local if called from client

[chrome bay]

A client can receive multicast RPC's from the GameState however. It will not receive Client RPCs

[fathom aspen]

It's clear

[chrome bay]

What was the question again 😄

[fathom aspen]

This how it all started

[fathom aspen]

Did I say it does?

I wasn't talking about GameState at that pint

[fathom aspen]

You see your problem

You don't say complete sentences

That can very much misleading

Ok that was next sentence xD

You can keep going back to the chat and trying to find me wrong

[twilit radish]

I think you both are getting things a bit mixed up, relax. You both got the same spirit lol.

[fathom aspen]

Also I answer in this chat regularly. You are welcome to prove me wrong at any point

[twilit radish]

Both of you're are trying to say the same thing but are confusing each other haha

:/

[fathom aspen]

Yes that's the only thing you're good at trash talking. I get to block you now so I make sure I don't see lame messages in this chat

You literally messaged me a few days ago from another account trying to understand my history, and now you're with new account trying to brag with your skills. Not on me boy

Danii

Just for the reference:

[twilit radish]

Guys.. Just stop please. If you don't like each other fine by me and the rest I assume, you both had the same idea but both didn't seem to understand each other's intentions. But this is just really unnecessary.

[latent heart]

To be fair, you can call an rpc from anywhere on any system, it's what you call it on that matters (with respect to if it actaully runs)

It may run locally.

[twilit radish]

Most RPC/multicast related stuff still runs, but it gets executed locally yeah (although is likely not behaviour you want).

[latent heart]

You absolutely can, @quiet rapids

[fathom aspen]

Even multicasts can be called from client, though they will run locally. so my "iirc" was even correct

[latent heart]

A multicast one on gamestate will run quite happily, locally.

[latent heart]

A server one will do nothing, however, unless it's run... on the srever.

Yes they will.

The only things that are dropped entirely a single-cast RPCs called on the client to the server on an actor that isn't an autonomous proxy on that client.

That does not include a listen server calling a server rpc on a different client's actors.

Even though you might expect that to fail because "oh, not srever, we're the client at this point!!!111"

[twilit radish]

Listen Servers are weird honestly xD

Lets make everything a dedicated server, easy fix.

[fathom aspen]

Dedicated servers are ❤️

Their prices though

[twilit radish]

Make a good game, then get bought by Epic the moment you're going to go bankrupt and all problems are solved 😛

[latent heart]

You can spool up a dedi server locally still to fake a listen server 😛

[rotund onyx]

Hey guys I am still struggling to get my players' selected color to load when they join a server.
Currently I'm trying to get them to load their config when they join a server but it doesnt seem to work properly, because everyone only sees their chosen color on all other players.

[latent heart]

How are you 1) sending this colour 2) storing this color 3) retrieving this color

[rotund onyx]

I am trying to store it in the playerstate so it is easily accessed by everyone

[low flame]

I may have posted this in the wrong channel, would anyone know how to solve this local multiplayer spawning issue #blueprint message

[rotund onyx]

the color in config I can represent in whatever way. Currently its just a text doc with a string

[latent heart]

Why would you not use the config stuff?

Save it to an ini file?

So how are you sending the color to hte server when you join?

[rotund onyx]

because I dont know how to do that

reading the file

its just a string

[latent heart]

Just marking the value as config should store the value and read it back automatically.

In BP at least, you have to do an extra step to save in c++

[rotund onyx]

honestly I havent even heard of that

[latent heart]

I'm not suire what the default config is for games.

[rotund onyx]

I'll worry about storing it later

[latent heart]

But there will definitely be a way to do it

[rotund onyx]

I know my text doc works because the color does load

[latent heart]

That's fine.

[rotund onyx]

it just loads on all players instead of just the owner

[latent heart]

So how are you sending it to the server?

[rotund onyx]

this is in the playerstate

LoadMPOptions just loads the file

ignore the timer

[latent heart]

Nothing there sends info to a server

[rotund onyx]

how should I do that?

[latent heart]

You want an "executes on server" node

Not "executes on owning client"

[rotund onyx]

how do I make sure only the owning client loads their file?

I dont want the server overriding it

[latent heart]

Use the player controller

the begin play, don't use a timer

check if it's the local controller

Then run an 'execute on server' node

The parameter being your chosen colour and whatever else you want to send.

On the server end, set the value for colour (and whatever else) in the player state connected to the controller and make sure the variables are set to replicate

Your MP options should load once, at the start of the game instance, not every time you join a server

You can store them on yoru game instance (where you can set them as config variables) or a user settings class somewhere

[rotund onyx]

I'll give it a shot, thanks

[woeful lantern]

Hello, do somebody know why the child actors are not replicated here? This is how I spawn them.

[dark edge]

Are you using child actor component?

[latent heart]

There should be a pop-up when joining the server, "Are you using child actor components?" If you click yes, it just bans you.

[dark edge]

You're probably spawning on client too, don't do that. Spawn a replicated actor on server

[dark edge]

I wish we had a nice way to embed actors tho.

[latent heart]

A prefab sort of thing

[dark edge]

Modular stuff is a pain with the Actor/Component split.