multiplayer

[fallow shadow]

Soon (in about an hour)

[quasi tide]

@dark edge I wanted to revisit the gun component idea (I was too busy earlier to ask about it). More of an overall design question. Does it not get annoying setting up new actors to bind to any gun comp functionality? Such as firing or reloading, etc.

[dark edge]

We have items with Activate/Deactiveate Primary/Secondary, and the item decides what that means.

So a shotgun fires on activate primary

a machine gun starts auto firing on activate primary and stops auto firing on deactivate primary, etc.

We use projectiles in our case so no GunComponent but the idea still holds.

[quasi tide]

Gotcha. So a base item class and you just subclass that when you want a new one?

[dark edge]

yup

[fallow shadow]

i am BACK

ok so

void AMyCharacterBase::SERVER_start_firing_Implementation() 
{
    IsFiring = true;
    
    const FRotator SpawnRotation = GetControlRotation();
    const FVector SpawnLocation = ((FPMuzzleLocation != nullptr) ? FPMuzzleLocation->GetComponentLocation() : GetActorLocation()) + SpawnRotation.RotateVector(GunOffset);

    SelfWeapon->primary_fire(SpawnRotation, FPMuzzleLocation->GetComponentLocation(), SpawnLocation, this, Mesh1P, FirstPersonCameraComponent, GetCapsuleComponent(), true);
    CLIENT_start_firing();
}

this is what executes first when the lmb is pressed

UFUNCTION(Server, Reliable, WithValidation)
void SERVER_start_firing();

this is the declaration
actually have both:

UFUNCTION(Client, Reliable)
void CLIENT_start_firing();

[quasi tide]

Yeah - seems quite similar to the actor approach, just slightly less inheritance.

[fallow shadow]

@dark edge for visibility

going insane with this shit

why wont it exist wtf

[young spoke]

whats best way of getting the network id of a player from a client instance? do ppl use
GetWorld()->GetFirstPlayerController()->GetLocalPlayer()->GetCachedUniqueNetId()

[winged badger]

i read them from PlayerStates

[pulsar lotus]

How to join or find session by ip?

[delicate jay]

im not sure whether to put this in #multiplayer or #cpp but im trying to make an fps multiplayer (new to multiplayer) and for equipping the weapon actor i was wondering what the easiest/most efficient way for me to make it so the owner sees it attached to the firstpersonsocket and everyone else sees it attached to the thirdpersonsocket would be, this is what I have right now and it only attaches to the firstperson so everyone sees it attached to the firstperson, thank you (:

[dark edge]

Well you commented out the third person part.

How are you choosing which mesh to attach to? Does the 3rd person mesh not exist on the owning client?

[delicate jay]

thats what idk how to do, both meshes are on the owning client but i dont have the third person one rendering on the owner client

if i uncomment that then it shows on the third person socket only for everyone, not both of them or something like that

[dark edge]

Did you write that code or copy it?

Read it line by line

It is working exactly how you told it to

[delicate jay]

i know it is

there isnt a problem with it im not asking for a fix

[winged badger]

both sockets begin RIghtHandSocket is not a problem?

[dark edge]

OK so how are you detecting the owning client in the first place?

do that same thing here

OR

[delicate jay]

its on different meshes so i didnt think itd be a problem but idk

[dark edge]

It's not a problem, you just have nowhere that this code will behave differently on an owning client vs anywhere else.

[delicate jay]

yeah ik idk how to make it so it does tho

this is my first time doing multiplayer stuff before

[dark edge]

How are you handling the meshes?

You're presumably already hiding/showing based on net mode or whatever

do the same thing

Or better yet, make some function that does that and returns the mesh to use

[delicate jay]

in blueprints i just ticked the thing render if owner

[dark edge]

and use that function here

[delicate jay]

so it renders if your the owner and if not you dont see it

[winged badger]

well, fun thing about replicated actors, they tend to replicate the Parent they are attached to

[delicate jay]

setownervisibilty

[winged badger]

and then attach to it OnRep

[dark edge]

Is that a part of Replicate Movement?

[winged badger]

no

[dark edge]

Dafuq, it should be

that's dumb lol

[winged badger]

if you're attached you shouldn't really be moving around much

on your own

[dark edge]

I mean that attach parent should be a movement-related property, but my project does nothing of this sort so I've never encountered it

[delicate jay]

also im not sure if this matters but the two meshes use the same skeleton, the skeletal meshes are different but the skeletons are the same so it actually does use the same socket

[devout berry]

Hello all.
I have a respawn method in my gamemode, but when I try to call an RPC from the player controller to get the gamemode, the cast to my gamemode class fails on the client.

How exactly can I request a method on the gamemode from within a client player controller?

[dark edge]

You sure you're doing it on the server?

[winged badger]

when you attach something on server, you generally don't need to do it on client

/** Handles attachment replication to clients.  */
USTRUCT()
struct FRepAttachment
{
    GENERATED_BODY()

    /** Actor we are attached to, movement replication will not happen while AttachParent is non-nullptr */
    UPROPERTY()
    class AActor* AttachParent;

    /** Location offset from attach parent */
    UPROPERTY()
    FVector_NetQuantize100 LocationOffset;

    /** Scale relative to attach parent */
    UPROPERTY()
    FVector_NetQuantize100 RelativeScale3D;

    /** Rotation offset from attach parent */
    UPROPERTY()
    FRotator RotationOffset;

    /** Specific socket we are attached to */
    UPROPERTY()
    FName AttachSocket;

    /** Specific component we are attached to */
    UPROPERTY()
    class USceneComponent* AttachComponent;

    FRepAttachment()
        : AttachParent(nullptr)
        , LocationOffset(ForceInit)
        , RelativeScale3D(ForceInit)
        , RotationOffset(ForceInit)
        , AttachSocket(NAME_None)
        , AttachComponent(nullptr)
    { }
};```

[dark edge]

Then how do you even know it's not working? It should look the same no matter what, just the meshes are swapped out, right?

[winged badger]

its in USceneComponent, so this would require Root component to be replicated for it to break

[dark edge]

NVM, they share a skeleton asset, but you're not doing master pose or any of that stuff.

So how DOES one attach an actor to different things on different machines?

[delicate jay]

good point ill try changing the skeleton aswell

[devout berry]

@dark edge I don’t follow your question. I wrote I am trying to call a rpc from the client Pc to a game mode

[dark edge]

Show your code

[quasi tide]

Do a server call to the server PC then in the server function call the method on the game mode.

the cast to my gamemode class fails on the client.
This makes sense - gamemode doesn't exist on the client.

[devout berry]

I am under the impression, that is what I am trying.

[fallow shadow]

im desperate :(

this is really weird

can you atleast give me some debugging tips

do you need more code? i can give more code

[dark edge]

You aren't showing the business end of the firing logic

[fallow shadow]

gimme a mo

void UMyRevolver::primary_fire(FRotator rRot, FVector vMuzzleLocation, FVector vLoc, UObject* context, USkeletalMeshComponent* Mesh1P, UCameraComponent* FPCC, UCapsuleComponent* capsuleself, bool SERVER) {

    const FRotator SpawnRotation = cRot;
    const FVector SpawnLocation = cLoc;

    if (GetWorld() != nullptr && SERVER)
    {
        FActorSpawnParameters ActorSpawnParams;
        ActorSpawnParams.SpawnCollisionHandlingOverride = ESpawnActorCollisionHandlingMethod::AlwaysSpawn;

        // spawn the projectile at the muzzle
        AgfProjectileHitscanB* prjHitscan = GetWorld()->SpawnActor<AgfProjectileHitscanB>(SpawnLocation, SpawnRotation, ActorSpawnParams);
        prjHitscan->spawn(FPCC, MuzzleLocation, capsuleself, [=](FHitResult fhrResults, UWorld* world) {
            if (fhrResults.Actor->IsA<AMyCharacterBase>())
            {
                AMyCharacterBase* Casted = Cast<AMyCharacterBase>(fhrResults.Actor);
                Casted->set_health(Casted->get_health() - 65);
                client_notify(Casted->get_health());
            }
        });
    }
        if (!SERVER) {
            // All of that animation and sounds and other client side stuff
        }
}

the way i do this is i use the same primary fire function for both the client and server side stuff because its just less code

this is really weird

so i have another weapon that spawns actual projectiles

if i try using it in this arrangement the actors spawn... but they seem to use some sort of weird logic

blueprints tell me that they have a 999 lifetime (which is what i set for debugging) but they despawn within 15 seconds

or that their spawn speed is 1000 units but they are going at some 10000

[fathom aspen]

It should be working fine. You don't have to call an RPC. OnUnPossess is called only on server on PC

And if it does get called on client, ask yourself how you destroy a replicated actor on client beforehand?(but quite sure it's not)

[devout berry]

I usually get weird behaviour when I destory a pawn directly after unpossess. For some reason I still need a delay.

(Unrelated to what you said. Did not know that event is allegedly only on the server)

[dark edge]

@fallow shadowIs the weapon owned by the client?

[fallow shadow]

yes

its an AActor component

defaultsubobject'd to the character

(client)

[dark edge]

Wait wtf your weapon is a component but you spawn an actor to shoot

this is all sorts of fucky lol

[quasi tide]

https://tenor.com/9J2v.gif

[fallow shadow]

Ok i could change but i dont think that would fix the issue

[fallow shadow]

.

[dark edge]

@fallow shadowSo if you do a print string, does the run on server event fire as expected? Are you sure the problem is the actor being spawned, not the RPC to begin with?

[fallow shadow]

im not too sure but im pretty sure the RPC itself works as intended

i put a dummy variable in the RPC and every function it invokes to check if it has authority (its the server) and it always was

[karmic shuttle]

is there any way to make my replicated variable update instantly? a run on server event from the client doesnt update the replicated variable for almost 5 seconds

[dark edge]

There's a force replication function somewhere.

It's updating slow because your net update rate on that actor is low

[fathom aspen]

ForceNetUpdate

[karmic shuttle]

im on a blueprint project, is it still accessible?

[fathom aspen]

It is

[karmic shuttle]

ah where would this be?

[fathom aspen]

On any actor really

[fathom aspen]

This is a function

You call it after you change your replicated property/variable

[karmic shuttle]

hmm im running this after a cast

is this alright to run outside of the place im updating the variable? appreciate all the help

[fathom aspen]

Yes. Also make sure you are doing all this stuff on the server

[karmic shuttle]

yep its on a run on server event

[eternal canyon]

u dont need an rpc

[proven grove]

Hello guys,
I am learning the multiplayer on Unreal and I was wondering if the server-side of a game was only the gamemode? I mean, I'm trying to make a little game with a dedicated server but I'm not sure where to put my server logic, even if the gamemode sounds logic to me. Will clients be able to access to gamemode too or it is only for the server?

[winged badger]

Check pinned messages on this channel, find Cedric's network compendium and read it

there are just too many questions to ask them here one by one @proven grove

[proven grove]

👍 I'll look for it, thanks

[karmic shuttle]

so i have a actor in the world which i want to display a clientside widget but the actor seems to be running on the server even though replicates is set to off

would anyone have any idea how i would make the client control the actor without replication?

[crystal crag]

With a dedicated server, even though there isn't a local player like with a listen server, is there still an instance of ULocalPlayer on there for each player actually connected to it, or does it only exist client side?

I'm guessing the latter, but was looking for confirmation

[fathom aspen]

The dedicated server instance is no player. Not like the listen server. ULocalPlayer exists only client side, for each client, and server-side for the listen-server player

[fathom aspen]

Replication set to off means your actor won't be replicated to clients if spawned on server. If it's spawned on client, then it's on client, you don't need to replicate it, though the server has no clue it exists, and it won't be synced using the replication system(if you want that). So replication set to off doesn't say anything about where an actor exists, so you need to know where it was spawned.

[karmic shuttle]

its preplaced in the world

[fathom aspen]

You don't create widgets for such actors

It just doesn't make sense

You create widgets for players so they are added on screen

Players through PlayerStates/PlayerControllers/Character have a client-side and so widgets can be created there and added to screen accordingly

[karmic shuttle]

its a vending machine which displays the players items and money clientside in the world

do you have another method in mind?

[fathom aspen]

Ah so it's not UMG

but 3d widgets

[karmic shuttle]

its umg

[fathom aspen]

Ok then create for the player

[karmic shuttle]

i create the widget on the player and pass it in to the actor in the world

[fathom aspen]

A vending machine can't interact with widgets

[karmic shuttle]

oh i have all the stuff set up and working but its the multiplayer replication thats weird

[fathom aspen]

Check this out: #multiplayer message

It's a life saver

[crystal crag]

@fathom aspenI knew the dedicated server didn't have a player by default, but as players connect to it, I wasn't 100% sure (until now) whether or not a ULocalPlayer was created on the server side (and not replicated)

thanks for the reply

[fathom aspen]

until now means you still not sure? 😄

[crystal crag]

No that meant until you gave me your answer I was not sure

🙂

[karmic shuttle]

@fathom aspen i call this from the client

but it seems like these variables are serverside saved in the actor even though theyre just called from the client on remote

[fathom aspen]

This doesn't say much to me. And yes you are using widget components which can exist on both server and client. Take the time and read that compendium I pointed out, as you seem to lack basic networking knowledge

[crystal crag]

If he is using a dedicated server he might have to check that checkbox that loads umg on the server side. I think it's unchecked by default

I haven't read the conversation chain, so sorry if what i said was way off point with where you are at with things

[fathom aspen]

load umg on server-side?

umg is client only

[twin juniper]

Any help is appreciated!

I'm of the opinion that the Simulated Proxies don't need to use physics at all, and the movement must be taken solely from the authority

can someone tell me how to figure out what functions should be server sided and client sided

[crystal crag]

Right but there is an experimental option to load it on dedicated servers

I'm pretty sure there is at least. I've never used it though

[fathom aspen]

1. Practice makes perfect. The more you dive through the source code, the more such stuff become so easy to remember.
2. Use your ration. If the function is doing some authoritative stuff then it's prolly server only.
3. Ask in this channel

[twin juniper]

mhm okay thank you

[fathom aspen]

I don't know about it, and it's 100% not what he wants

[crystal crag]

Ufunction(blueprintauthorityonly) functions are only meant to be run on the server. Also yes, as wizard said, if the methods implementation is wrapped in a check for "Is authority" then it is meant for the server. If it checks if it's not server then it's meant to be run on the client

@fathom aspen ok, fair enough

[pale pewter]

Is it okay to use client shipping build to connect to dedicated server development build?

[ivory island]

How do we replicate the actors we created from the GameMode to the clients? We're using a node in the GameMode to create actors, but those actors are not replicated. We also replicate an array of actors, the array is replicated with 2 entries, but the references to the actors are gone.

[fathom aspen]

Nothing really special here. Like you would replicate any other actor out there. Make sure the actor bReplicates and that you spawn it on server. GameMode is server only, so you're safe

You can't have a replicated array/property in the GameMode as you can't access the GameMode from clients. It doesn't make sense to have replicated properties in the GameMode

[twin juniper]

anyone?

[nova wasp]

Intax made this a while back I guess https://github.com/intaxwashere/basictransformreplicator

unsure if it's a big help

[twin juniper]

checking out right now

Oh shoot I was right

I have to simulate movement manually on the simproxies

What's Vector Interp, or FMath::VInterp?

[nova wasp]

yep, there are two of them though

one is linear

i think that one is smoothed a bit

iirc...

[twin juniper]

Yes, Cubic Interp basically helps for when the ping is bad by making educated guesses about position and velocity

lerp/vinterp should in principle be accurate for extremely short client sim deltatime

[nova wasp]

my internet could help demonstrate the magic of long distance movement corrections

[twin juniper]

trust me, I'm Indian, I know

the switch between Slerp and RInterp is also illuminating

[forest bolt]

Hey Guys, I'm implementing an assymetrical jump in multiplayer and what I basically do is use the jump system already in the character and change the gravity scale and velocity mid-air to my needs. However, even with a reliable RPC sometimes there's some correction between the client (the autonomous proxy) who is jumping and the server, causing jittering. But looks completely normal for the other clients.

Is there anything wrong in using the gravity scale for this? Any insights on how to make it work?

[forest bolt]

Jump Started on the left. Server locations are displayed in red and client in green. They differ after the apex and then the server corrects it.

[hollow eagle]

Unfortunately there's no easy fix for that - you likely need to implement a custom FSavedMove to handle prediction and rollbacks.

There's a bit of general info on how CharacterMovementComponent handles replication and prediction here - https://docs.unrealengine.com/4.27/en-US/InteractiveExperiences/Networking/CharacterMovementComponent/
Fair warning, this is fairly complex stuff and it's incredibly underdocumented. Also not something you can do with pure BP.

Other workarounds may include custom movement modes or root motion, but those have their own complexities.

[forest bolt]

thanks for the valuable resource! I already have some bits of my mov comp in CPP, I'll check the page to improve my knowledge and start getting my hands dirty on this. Thanks a lot!

[hollow eagle]

fyi the important bit is the last section at the bottom - "Customizing networked character movement". The rest of the page is definitely useful as it goes into detail about how prediction works, but the actual things you have to do are just in that bottom section.

Also take a look at root motion sources (mentioned on that page) which may provide a simpler way to do things depending on how your jump works.

[forest bolt]

Awesome, I think there's some of this implemented in GASDocumentation

[forest bolt]

Root motion would be way simpler, but I need air control

[hollow eagle]

it technically doesn't need to be from an animation if that's what you're thinking it is - a root motion source could be completely programmatic

I haven't worked with root motion sources much myself but you might be able to get one to just control vertical velocity while still allowing for normal air control.

[forest bolt]

this sounds like a really good idea

I'll explore this first before trying the custom movement

[hollow eagle]

If it works (and I don't know if it will) it'll probably be much simpler. Good luck!

[forest bolt]

thanks!

[hushed spoke]

Hello everyone, I have a switch weapon system that I’m trying to replicate. The player holds a child actor component, and when they switch weapons, it’ll set the child actor class to a different one. However, when I attempt to set the child actor class to a new one, all players are affected.

https://i.imgur.com/ctDCg6w.mp4

[lament garnet]

couple of things.. a system like this is better handled using repbotifies

and child actor component is trash, ill never trust it

[hushed spoke]

It made my life so much easier, rather than destroying actor and spawning a new one

[hushed spoke]

I'll try repnotifies, but why do u think it would solve the issue? Do you know why it's happening?

[lament garnet]

im not sure

[winged badger]

with CAC, you never know, might be modifying the CDO

[lament garnet]

actually you can reuse the same actor and change properties accordingly to a data asset for example, thats how ive done it in the past

[winged badger]

breakpoint in the c++ with debugger required

[hushed spoke]

I read that if I spawn the child actor on runtime instead, then the server will modify the instances instead

[hushed spoke]

So instead of having multiple classes for each weapon, one class will contain all the weapon data (bullet, mesh, animations, etc.) and I switch it there?

[lament garnet]

yes you can have a single class with a data asset that has the different stuff such as meshes etc. when you switch weapon you only change the data asset and update the data accordingly

you need to store stuff like bullet counts outside tho, i had a struct for each weapon and a struct that rappresent the currently equipped one

[hushed spoke]

I'll keep this idea as a backup plan, because doing such a method would change nearly all of the mechanics I already added

But as I said I read that if I spawn the child actor on runtime instead, then the server will modify the instances instead

Do u know how I could spawn the child actor component on runtime?

I tried it, but it wasn't spawning anything

[lament garnet]

just like any other component, you create it and register it to the world

[hushed spoke]

This does not work

[swift turret]

any idea what is in these packet?

[twin juniper]

Guys do j need to maintain seperate codebase for character that replicates and character that work in standalone game??

Can you tell me how to do it.Do I have to use of statements to achieve that

*if statement

Let's say my stand alone character can shoot directly while my multiplayer character needs to send an RPC to server and from that server need to get a multi cast function then he can show the visual effects.

I am talking about dedicated server

Then I think it won't work..

I wrote my character code assuming I am connecting to dedicated server

Thanks for advice.

[red salmon]

Can somebody help me with a link to a documentation/ tutorial about steam to ue4 security info, like how to make a proper moderation system or how to not leak IP addresses of players?

[fallow shadow]

OK-AY I am back

[plucky prawn]

dont use P2P. make all your clients go through the server for everything. if player A wants to send a chat message to player B, make player A RPC to the server with the target player (player B) and a string field or something. then the server would RPC to player B that they received a message from player A

[fallow shadow]

so i still have the issue where the code executes but nothing happens

i even stopped using the actor for hitscan bullets and now i directly do the line trace from the weapon actor component

[red salmon]

I pretty much already have that, I am worried that my systems for server moderation and IP leaking are gonna have some big problems. I am looking for some documentation on how to make a good server moderation system and how to hide player IPs better.

[meager fable]

How can I get my IP adress and port when running a dedicated server?

[bitter oriole]

By asking an external service to tell it to you

[meager fable]

by exteranal service you mean?

[bitter oriole]

A server on the Internet

[meager fable]

Still not sure how to do that, could you elaborate or provide some code example?

[bitter oriole]

Write yourself a server in PHP or something that simply prints the client IP

Send HTTP request to said server

Read response

Alternatively since it's 2022, use sessions

[meager fable]

There is seriously no other way the IP and port where I'm setting up a server than making another server and checking where the response comes from?

[twin juniper]

Does UE5 replicate physics?

I saw in the handful of cases I have been diving into, that it usually isn't possible. I must use custom cubic interpolation logic for the simproxy.

Then there are things such as prediction for autonomous proxies that I don't know about. Any idea where to look?

[bitter oriole]

Correct

Your machine fundamentally does not has access to this information

You'd need to find the network access point and ask it (how?) its public IP

In practice both parts of this sentence are very big "how"

Hence the easy answer: go ping a server

[twin juniper]

Oh does OP trust whatsmyip or similar sites?

[fallow shadow]

what if you ping yourself

also im back uhhhh so

i have confirmed that the code does in fact run on the server

the line trace just

doesnt happen

it doesnt happen

why

idk

it works if im on a listen server and the server tries doing it

but if a client it doesnt

[twin juniper]

Please help!

[azure viper]

Same problem, but use search. Better let client Calc physics and just submit rotation, velocity etc to server 😂

[chrome quest]

@chrome bay sorry for the ping but if I want to NetSerialize FInstancedStruct without modifying engine files, can I just inherit the struct and add the function there?

[twin juniper]

I mean that's the plan but when I try that, chaos ensues (no pun intended). The pawns start vibrating like there's no tomorrow.

I need to figure out how to adapt the sample and the off-the-shelf script

I'm using the simple Transform Replicator plugin from the chat. So far it fits everything I need a simproxy to do

I haven't explored any autoproxy-side logic, and I guess I need to look deeper.

My laziness and inertia are keeping me from it but I guess I can do it.

[chrome bay]

In theory yes, but you of course lose a lot of the editor support for the struct itself.

[chrome quest]

It wouldn't carry over to the child struct?
Also, what kinds of editor support?

[fallow shadow]

gonna ask one more time because im suffering so much oh my god

i have a character that can fire their gun right

ok so it goes like this

character -> call server rpc -> weapon (actor component) -> do line trace -> respond to line trace results -> call client rpc to do all that client side stuff like sound and animations

The issue is that the line trace doesnt happen

actually nothing that interacts with the world works

spawning actors or line traces etc etc

and before you ask yes the server rpc executes and yes it is actually on the server

i checked with HasAuthority

[rapid bronze]

Did you set the component to replicate?

[fallow shadow]

uhh how do i do that?

bReplicates kinda doesnt work im p sure

[chrome quest]

SetReplicates()?

[fallow shadow]

Ill try

nope doesnt exist

[rapid bronze]

Component->SetIsReplicated(true);

[fallow shadow]

just as a PSA im inheriting from a base class that inherits from UActorComponent

[chrome quest]

Oh right. This

[fallow shadow]

nope doesnt work

[winged badger]

whats the last point that executes?

[fallow shadow]

if you're asking me, the if statement where i draw a line trace

actually what do you mean "last point"

[winged badger]

put breakpoints along the execution flow

and see whats the last one that hits

[fallow shadow]

Ohh yeah then its the if statement where i try to execute the line trace

if the line trace hit anything it would've entered the if statement which doesn't happen

[winged badger]

so there you go

this should not be treated as a multiplayer, but a collision problem now

or math

depending which part of the trace is broken

[fallow shadow]

yeah but you see the thing is

if i draw a debug line with the exact start and end point that the line trace uses

it does hit stuff

both stuff i can see and cant see

and if i fire from the server on a listen server it works perfectly

[winged badger]

does it hit stuff, or does it go through?

[fallow shadow]

it goes through

by hit i mean i can if anything visualise the line trace and it definitely goes through a wall or character or anything else

[winged badger]

you'll need to show code, describin g it is very inefficinet

[fallow shadow]

Aight

    if (GetWorld() != nullptr && SERVER && GetOwner()->HasAuthority())
    {
        FActorSpawnParameters ActorSpawnParams;
        ActorSpawnParams.SpawnCollisionHandlingOverride = ESpawnActorCollisionHandlingMethod::AlwaysSpawn;


        FHitResult OutHit;
        FCollisionQueryParams CollisionParams;
        CollisionParams.AddIgnoredComponent(capsuleself);

        FVector Start = muzLoc;

        FVector ForwardVector = FPCC->GetForwardVector();
        FVector End = ((ForwardVector * 4000.f) + Start + FVector(0, 0, -100));

        if (GetWorld()->LineTraceSingleByChannel(OutHit, Start, End, ECC_WorldDynamic, CollisionParams)) // The last breakpoint hit is here
        {
            if (OutHit.bBlockingHit)
            {
                if (OutHit.Actor->IsA<AgfClassBase>())
                {
                    AgfClassBase* achCasted = Cast<AgfClassBase>(OutHit.Actor);
                    achCasted->set_health(achCasted->get_health() - 65);
                    client_notify(achCasted->get_health());
                }
            }
        }

    }

[dark edge]

@fallow shadowIf you show debug on that trace does it look correct?

[fallow shadow]

wait a second debug on trace?

[dark edge]

const FName TraceTag("MyTraceTag");

World->DebugDrawTraceTag = TraceTag

FCollisionQueryParams CollisionParams;
CollisionParams.TraceTag = TraceTag;

incorperate that

[fallow shadow]

aye aye

wait what am i supposed to see?

i dont see anything when i fire

Oh ok i fired from server

its a white line and a red marker where it hits

uh

yeah this doesnt happen at all on the client

[winged badger]

and how would the client draw a line?

all you send it is the health

it doesn't have any hit information

[fallow shadow]

wait wait wait that's only there to update the hit clients' health

if i remove it everything stays the same except the client doesnt know its hit if it gets hit

the issue is still that the client just cant shoot

it calls a linetrace on the server

it just doesnt happen

Actually no correction

if i remove the client_notify line nothing changes

it just works as intended

[dark edge]

Watch on the server when the client fires

[fallow shadow]

wdym by "watch"

[dark edge]

literally watch

you're doing listen server right?

Although you really oughta just work your way back from that trace with breakpoints and figure out where it's busted at.

[fallow shadow]

yeah

which is just for testing the game is intended to be played on dedicated

im watching

im looking at the client that's shooting the bullet

no thin white line appears

nothing

[dark edge]

well then you're breaking before the trace

put breakpoints everywhere, track down the last on that gets hit

[fallow shadow]

aight

[dark edge]

Might be simpler to just print to log at each step calling out what the step is but you do it how you want

[fallow shadow]

might put a few breakpoints in the linetrace itself too

nope

nothing breaks

it follow throughs on the line trace

[dark edge]

you're probably not making it to the trace, put breakpoints/debug logs everywhere from the input to the trace

[fallow shadow]

I did that's the thing

on literally every line up to the trace i could

and it followed through

it entered the trace

[chrome quest]

@chrome bay, sorry for the ping again. I've been able to make a child instanced struct replicate. Works fine.

I'm assuming by editor support, you meant the make/break nodes you created right?

[fallow shadow]

hell i even had a few breakpoints in the trace method and it reached all of them

[halcyon totem]

ok I am trying to set my view pitch on event begin play but when I do its setting the view pitch on all the other players?

its not suppose to do this as its a child class. does anyone know why this is happening?

[fallow shadow]

@dark edge i finally figured it out

So the reason it doesn't work is really stupid

The way i do this is to avoid repetition

the RPC to the server is in the base character class

for some reason calling a function in a base class as an RPC doesn't work

[chrome quest]

🤔

[fallow shadow]

i made a test function that does the same thing except its directly in the character class im playing as and it worked

[chrome quest]

That's strange.

It should work.

[lament garnet]

i should be able to launch two standalone games and connect between the two on the same pc right?

[torpid nymph]

when I start my game as a client, there's a few frames where I can see the map before I actually possess a character ( I start at 000), I want to hide that transition by immediately going to fade to black before I actually get a character assigned, I remember fixing this issue quite a while ago but can't remember how

[lament garnet]

good luck with that, the only solution i have found so far is the fading thing

[torpid nymph]

which fading thing? I don't get a proper fade until after a few seconds after I'm already in the game 😦

[lament garnet]

https://nerivec.github.io/old-ue4-wiki/pages/global-fade-in-out.html

[torpid nymph]

so I still get a few frames of seeing the world before it does the fade

[lament garnet]

make your own gameviewportclient

[torpid nymph]

nice, will look into that

[lament garnet]

i need some help :\

im trying to joing a session between two standalone instances

when i join the server get this
[2022.06.21-20.07.07:218][145]LogNet: Verbose: UNetConnection::SetClientLoginState: State changing from LoggingIn to Welcomed
[2022.06.21-20.07.07:258][146]LogNet: Verbose: Level server received: Netspeed
[2022.06.21-20.07.07:258][146]LogNet: Client netspeed is 100000

and the screen go black

the second i alt-f4

i get this

[2022.06.21-20.07.42:744][319]LogNet: Verbose: Level server received: Join
[2022.06.21-20.07.42:744][319]LogNet: Join request: /Game/Maps/MainMenuMap?Name=ZENITH-xxxxxxxxx?SplitscreenCount=1
[2022.06.21-20.07.42:745][319]LogBlueprintUserMessages: [GameplayGameMode_BP_C_0] TempPlayerController_BP_C_1
[2022.06.21-20.07.42:767][319]LogNet: Join succeeded: ZENITH-xxxxxxxx

[chrome bay]

Ah I meant native editor support but it might be fine actually. Just beware of slicing if you pass an FInstancedStruct around still

[karmic shuttle]

is there any way to modify an actor's components and variables from the client completely clientside?
https://blueprintue.com/blueprint/qifwhf8a/
this event is from the player proxy but it seems as if these changes affect other players in game

[lament garnet]

was something weird in the DefaultEngine ini, now its fine 😐

[fluid summit]

Hi everybody! any reason as to why a RPC (on server) called from a UI using a reference to a replicated actor is not working?

[fathom aspen]

If the actor isn't owned by the invoking client, the server RPC will be dropped

[latent heart]

You can only use the controlled pawn, player state or player controller. Generally.

[twin juniper]

what should I do if my multiplayer save game system won't load the save for clients and only loads it for the server player I can't figure it out.

[latent heart]

Maybe the loaded stuff isn't set to replicate?

Or something.

Or you're spawning it wrong.

[twin juniper]

like the variables you mean

[fluid summit]

what is your setup and what is your desired behavior?

[twin juniper]

just checked all my loaded stuff is set to replicate I'm new to unreal and followed a youtube tutorial for the multiplayer replication save and load system can I send blueprint screenshots to somebody and maybe they can help me out further if not it's fine I'm sure I'll figure it out eventually

[fluid summit]

You can post them here, no problem

[twin juniper]

alright sure

[fluid summit]

Yeap, it was this. i used the Player state as a proxy for the call and worked.
I tought that when doing rpc from UI it would take it as a the Pc is doing it. Not the case 😬

[twin juniper]

so this is what I have in my eventgraph and then I also have 2 functions which are savegame and loadgame which is here

and obviously I have a playersDB and a save game and all of that stuff cause the tutorial showed me that but anytime I load in the game it only saves for the server and not the client despite it being set to server and multicasted and originally it wouldn't load at all but I figured out I was missing a connection

sorry for the blurryness

also the stuff offscreen in the load game screenshot is just it connecting to the variables again like in the save game screenshot

[fluid summit]

Okey i can see a few possible problems.

1. Put a few "print" to see if your methods are actually being called, you are making calls right after login and some actors may not be ready at that moment
2. Your save/load call, even if doing multicast, should be done on Remote and pass the data to a RPC on server. Or do a RPC "On Client" and from there, pass the data to another RPC "On server".

Remember that your save slots are local

[twin juniper]

can you elaborate by what you mean by remote and RPCs like I said I'm a beginner so I'm not really 100% certain about all the terminology quite yet might need a more simplistic explanation if possible lol or like an example or something

but atm I'm printing strings to see if the methods are being called

alright I put a few print strings and it seems that it's loading

and prints hello for all the print strings I put all along the blueprint so it must be the 2nd problem

[fluid summit]

Try to check this first or read the compendium by zedric

https://www.youtube.com/watch?v=JOJP0CvpB8w

[twin juniper]

alright

oh I think I get it.

let me see...

[fluid summit]

When you change a event to replicate, that's called a rpc.
What you need to do is make sure you are making your first call from the remote (the client). I assume you have a listen client setup.
So for it to also work on your Server player, you need to make it for all clients and tell them to do it on "Owning client".

From there, grab all the data that you need from the save game slot and do another event set to repliate "On Server" and pass all the data.

[fathom aspen]

First things first. Please don't follow tutorials. Other than this is what you get usually from watching them, they teach you bad habits.
Now to the code. GetPlayerCharacter(0) on server will return the listen server's afaik, so that may be the problem

You shouldn't be using GetPlayerXXX(0) at all. There are always other ways to get what you want

You got a Player param there which you can use

[twin juniper]

that fixed it

thank you so much

and yeah for now on I won't lol

actually nevermind it didn't fix it so I'll try acrisios suggestion next

and do some more research in relations to network replication

[fathom aspen]

Yes and you should read the compendium which you can find in the pinned messages

[twin juniper]

The gamedev.tv course and the compendium together made me understand the basics in less than 24 hours

[fluid summit]

The compendium and youtube made me understand that i don't understand the basic in less than 6 months

[viscid night]

Hi, I am facing an issue while updating AI's Widget component image across clients. What I am doing is one player enables the image of the AI's widget component but I am not able to replicate that across second client. I have read on forums that I can use a replicated variable and based on that update UI. I am not sure what a right approach would be to solve this.

[fluid summit]

what widget is it?

healthbar?

[viscid night]

Just an image that shows what State AI is in

[fluid summit]

if you want to change the widget directly, do a multicast.
The best would be to store a variable that determinates the state and do a OnRep.
With the OnRep you can check remote and update all the clients*

[viscid night]

I tried that. if the second client tries to update the variable, the listen client (client 1) doesn't receive the OnRep

Also AI cannot send a server RPC as it is not owned by the client and the server RPC will be dropped.

[uncut schooner]

You could have a replicated Actor and send the RPC through them

Like an AI manager

[viscid night]

But how would I notify (when I send a Server RPC and then Multicast to all clients) that I need to update widget component' image for that specific AI?

[uncut schooner]

Do the same function in the AI manager

And multicast there

Then it will happen on everyone

[viscid night]

Sorry I am not sure if I understood that correctly. I have this marking enemy function that calls Update Marked Icon event for the Current Enemy Character To Mark which further updates the widget component's image.

This marking enemy function is called in the third person character BP

[fathom aspen]

Multicasts are not for stateful events, so don't use them for sure. Use OnReps instead. AI states and data that players need to be aware of should go into AI PlayerStates. There is where you store AI data/states and it gets replicated to all players.

[viscid night]

Thanks for the response. How can I give an AI a PlayerState? I thought PlayerState is created for every player on a server!

[fathom aspen]

You do this bWantsPlayerState = true; in your AIController class constructor

[viscid night]

Thanks Very Much, I will try using the AI PlayerStates for storing AI data.

[fathom aspen]

Yes please. And just FYI, you can store them somehow in your player character class, but that's not where they are meant to be and it clutters that class for no reason

[viscid night]

Thanks Much, I understood

[fluid summit]

Mark the replicated variable as reliable could do the trick

[viscid night]

If I’m not mistaken, OnRep Notify is only triggered on the clients, thats why the listen client doesn't trigger it.

[dark edge]

in BP it fires on server, in C++ you gotta call it manually after setting the variable.

[viscid night]

I did that but how can I access/use that AI Player State?

[fathom aspen]

AController::GetPlayerState

Like you would get a player state for a PC

AIController inherits from AController

[viscid night]

thanks I got that but I couldn't figure how can I add variables n stuff to AI Player State as for a normal Player State for a PC we just create a BP and use it

[fathom aspen]

It's the same PlayerState class iirc

Yeah look into AController::InitPlayerState

That's the function that spawns the PlayerState

[viscid night]

thanks I will look into it

[fathom aspen]

AAIController::PostInitializeComponents what calls it

[viscid night]

thanks

[glossy plover]

What's the best way to tell all players to unprossess their characters (at the end of the game for example I want to freeze all characters?) Should I run a "On Server" event on the gamestate which is turn runs a "Multi Cast" event on the gamestate?

[winged badger]

no, gamemode should do that

and multicast is not required

also, default behavior will destroy the pawns on unpossess

[glossy plover]

I did it like this on the gamemode...this makes sense?

[regal narwhal]

Hi, Is there anyway to check if the session is still exist before join? I have basically list of session from the SearchLobby but the session owner might destroy before the client join.

[fallow shadow]

Ok i finally figured out why my character wont shoot

it cant draw a line trace from an UActorComponent

why????

[fallow shadow]

nothing happens if i try

if i draw the line trace directly from the ACharacter it works flawlessly

[quiet fjord]

How can I block a game that is already started so that no one can join my game, would it be done with update session?

[lament garnet]

on the client? on the server?

[fallow shadow]

server

[lament garnet]

reliable or unreliable

[fallow shadow]

reliable

[lament garnet]

i have no clue then 😆

reliable should work even if the component is not set to be replicated

[marble gazelle]

show some code^^

[fallow shadow]

this is the actor component declaration

    // Class weapon
    UPROPERTY(EditAnywhere, Category = Gameplay, Replicated)
    UgfWeaponBase* wSelfWeapon;

this is how i add it to the character

    wSelfWeapon = CreateDefaultSubobject<UgfWeaponRevolver>(TEXT("WEAPON"));
    wSelfWeapon->SetIsReplicated(true);

now on fire it runs a reliable server RPC that calls primary_fire from wSelfWeapon

in primary_fire is just a line trace that doesnt happen

but if i directly put the line trace in the server RPC it works

This is the server rpc

    const FRotator SpawnRotation = GetControlRotation();
    const FVector SpawnLocation = ((FPMuzzleLocation != nullptr) ? FPMuzzleLocation->GetComponentLocation() : GetActorLocation()) + SpawnRotation.RotateVector(vGunOffset);
        // If i just do a line trace here it will work properly 
       // wSelfWeapon->primary_fire(SpawnRotation, FPMuzzleLocation->GetComponentLocation(), SpawnLocation, this, skmMesh1P, ucFirstPersonCameraComponent, GetCapsuleComponent(), true);
    CLIENT_start_firing();

@marble gazelle

[marble gazelle]

So the RPC from the client -> server is received on the server. But the client doesn't receive the client RPC?

[fallow shadow]

no no that's not the issue

the issue is that

in the server RPC i call a function in an actor component

and in the function there is a line trace

the line trace straight up doesnt happen

but if i directly have a line trace in the server rpc it works

[marble gazelle]

works where on the server or on the client

[fallow shadow]

server

[marble gazelle]

is the server a dedicated one or just a master peer

[fallow shadow]

i test on listen servers but it happens on dedicated too

[marble gazelle]

Where should the line trace run, on the server or on the client

[fallow shadow]

ok wait let me do one more tldr; I want to do a line trace on the server:
this does not work:
input -> rpc -> weapon (which is an UActorComponent) -> line trace

but this works:
input -> rpc -> line trace

by works i mean it happens

[fallow shadow]

server

[marble gazelle]

well then set a breakpoint in your weapon code and check what happens^^

[fallow shadow]

it executes

[marble gazelle]

do you use the same coordinates?

[fallow shadow]

i checked already

yep

same code even

[marble gazelle]

well without the actual code I can't tell. if you run the exact same code it should work

[fallow shadow]

i just copy paste it directly into the rpc

maybe if i did input -> weapon -> server rpc -> line trace

i gotta try this first then ill send full code if it doesnt work

[marble gazelle]

that shouldn't matter, the question is, what information is your function taking from the weapon, is it the same info you take within the rpc

[fallow shadow]

yes

[marble gazelle]

did you check the debug draws?

[fallow shadow]

yes

[marble gazelle]

does the ray cast from the weapon create a debug draw?

[fathom aspen]

GameMode is server only. So there's no need to have RPCs at all, as each function/event will run on server

Read the compendium found in this channel pinned messages

[halcyon totem]

I have created an 1d aim offset but I cant put any animations on there

[fathom aspen]

#animation

[steady cape]

Is there a reason components might refuse to pass the multicast event to the clients, considering it and it's owning actor has replication enabled and no network emulation is done (a.k.a. no fakelag) ?

[short walrus]

Hello, does anyone know what is the best practice to replicate an array of objects (e.g. tarray of actors) from server to clients? For example, I'd like to replicate all the actors that are visible to my pawn and my team. If I try replicating an array like I replicate all the other stuff (Replicated annotation in property, entry in doreplifetime) it replicates the array size correctly, but all the pointers seem to be invalid

Is it a good practice to replicate array of objects? should i be replicating just object id's?

[steady cape]

Check if those actors have Replicated enabled

That's one reason I could think of replicated arrays are all NULL pointers

Oh, wait, objects

Yeah, those don't replicate on their own, so they can't exist both on server and client unless you manually manage them on both ends with some mutual actor that does replicates

Or you can just attach them to actor's net driver using C++ if you know how to do so

[pallid stone]

Getting this spammed constantly in my log
LogNetPackageMap: Warning: FNetGUIDCache::SupportsObject: PaperSpriteComponent /Game/2DSideScrollerCPP/Maps/UEDPIE_0_2DSideScrollerExampleMap.2DSideScrollerExampleMap:PersistentLevel.worldProceduralGenerator_1.PaperSpriteComponent_75 NOT Supported.

It's being made in the onConstruct script, once made, I have createdSprite->SetIsReplicated(false); But still coming up.

Any suggestions?

Code is

            createdSprite->RegisterComponent();
            createdSprite->AttachToComponent(RootComponent, FAttachmentTransformRules::KeepRelativeTransform);
            createdSprite->SetIsReplicated(false); ```

[short walrus]

Well for start I'm trying to replicate an array of actors. They all have replication turned on, and all are present on both client and server.

[steady cape]

Then Idk. Replicating actors like that has been working fine for me

[winged badger]

when is this?

to replicate an Actor pointer 2 things are required, a pointer to Actor has been replicated and Actor itself has been replicated

[uncut schooner]

Hi, Is there a good way for the server to check if the clients input matches their direction, For example if The player is running forward then it lets you run but if not it stops you?

[fallow shadow]

does the steam subsystem work in PIE?

[uncut schooner]

Is there a replicated Inptut vector variable somewhere?

[winged badger]

no to both of you

[quasi tide]

Zlo is being efficient with their answers. 🧠

[fallow shadow]

can someone assist me in installing the steam subsystem

and by assist i mean elaborate on what the fuck did the docs mean by "macros" here https://docs.unrealengine.com/4.27/en-US/ProgrammingAndScripting/Online/Steam/#serverdetails

how do i use them

where do i put them

[fathom aspen]

Don't cross-post. Ask in #online-subsystems

[fallow shadow]

aye

[fathom aspen]

As it reads. They are not network supported, and they can't be made such with ease afaik.
Pretty much like a decal component doesn't replicate. You shouldn't be replicating them even if they do support networking. You replicate the action you do. So let's say you are changing the SpriteColor. You change it after a player died for example. So you replicate a boolean bDied for example and when the OnRep is called you set SpriteColor

Replicate the action, not the entity itself

That way you save yourself some net bandwith, as you're replicating a simple data type

[fathom aspen]

This is really interesting. It does get called when you don't guard with authority. Wondering if that has to do something with the fact that we check owner's authority

[steady cape]

Not sure

That is kinda messing my other function call that is coming externally from my pawn (owner), and it's only serverside

Though, might recheck, maybe there are some switches

I'll delete them and see if it works

[steady cape]

Yeah, didn't really change anything

[winged badger]

component need to have replication enabled as well for that

[steady cape]

It is

[fathom aspen]

Oh right, that was it ^^

[sinful tree]

If the event begin play fires on the server before the actor (or component) exists on clients, how would they receive the multicast?

You may want to instead use an OnRep variable that you set on the server's begin play that can then trigger the OnRep function on clients as the actor (or component) begins on the clients once they are replicated to the clients.

[latent heart]

Except an onrep might not fire if the initial state of the character will probably include that changed variable if set on begin play

[dark edge]

Client might not exist yet

Does it work if there's a delay before calling Yeah?

[quiet fjord]

a question how can I use the filters for when I create a room in multiplayer

I want to put that when my room is complete that room does not appear in the find lobby

[winged badger]

you update session data

and filter them out client side if they are full

you also have session search filters

that do that for you

[lusty yarrow]

Hey guys, not sure where to ask this, but I want to securely send API requests to my web api. I own a certificate on the server, how would I go about using it to secure the data sent by the client?

Do I have to get the cert file and manually add it using the openssl implementation in the engine?

[steep panther]

how the heck do I get from a UMG panel to my admin controller on the server to run a kick player from server?

[winged badger]

dedicated server?

[steep panther]

yeah

[winged badger]

you don't

it has no players, so no UI

[steep panther]

so not really possible to do an admin panel that can kick players from in game?

[winged badger]

make an admin controller

that gets instantiated with say, a specific login url

engine not happy showing UMG on dedicated servers

every accident i remember when something tried to show it there, crashed

[steep panther]

figured it out

im not saying to have umg on server

[hallow sand]

😛

Told you it would work lol

Add server calls on player character, call character from UMG, bam server based UMG buttons

[graceful breach]

#multiplayer

[twin juniper]

bool UVehicleMovementReplicator::ServerSendMove_Validate(const FVehicleMove& Move)
{
    return Move.IsValid();
}

void UVehicleMovementReplicator::ServerSendMove_Implementation(const FVehicleMove& Move)
{
    if (const float ProposedDuration = ClientState.ClientSimulatedDuration + Move.DeltaTime;
        ProposedDuration > GetWorld()->GetGameState()->GetServerWorldTimeSeconds())
            return;
    
    OwnerEp->SimulateMove(Move);
    ClientState.ClientSimulatedDuration += Move.DeltaTime;
    UpdateServerState(Move);
}

@chrome bay just using this instead for now. Overticked moves are ignored so no kicking. Moves need to be valid though: the check simply involves seeing if the thrust and control values are in [-1.0, +1.0].

[knotty yacht]

anyone experienced with beacons able to help me out, I'm still learning them?
I'm saving address to user cloud upon successful connection and then in the event of a crash I'm spawning a beacon and try to connect to said address to see if session still exists.
Now if it does, it connects and everything works, but if it doesn't, calling
InitClient(url);
returns true, but the the beacon will just try over and over without ever failing.
Anyone might know the reason?

[quiet fjord]

Guys, how can I block a game that has already started so that new players cannot join?

is it done with the update session?

[steady cape]

Yeah, I fought BeginPlay is called when all clients have initialized it

Now I see this is not true

Well, thanks for that, but now I have another issue: it seems like my map isn't being replicated at all

Or (might have asked that in the first place) there are some way I can make replicated array be in the specific order?

This would rid me of making this workaround

[gusty raptor]

Hi, i used to parse option strings for my custom terrain generator in the gamemode

however so i moved that code to the actual actor, so it works on clients to

Is it only possible for server to parse option string? how would clients be able to use them?

[fathom aspen]

Make into a replicated property in the GameState and your clients would know about it

[fathom aspen]

Maps don't replicate

[fathom aspen]

What do you mean by "specific order"?

[steady cape]

So, if I have

0: Object1,
1: Object2
```it stays```
0: Object1,
1: Object2```across every machine it is replicated too

If I remember correctly, order of object doesn't persist with regular arrays

[fathom aspen]

Well there's no such thing to keep replication order. You never know how much time would it take each connection to get that replicated property

You should make it resilient with such cases

[steady cape]

So... I'm going to need to make one RPC with one object to be sent and then call it for every object in the array?

Because I need that order

Can't think of other ways to it

[fathom aspen]

Well here you face another problem. If you call the RPC from an actor that isn't relevant to a specific connection you never get that RPC fired in the first place for that connection

Read last pinned message in this channel so you get a better idea of when RPCs vs OnReps are used

[steady cape]

I know when those are used

[fathom aspen]

Can I ask what you are trying to do?

[steady cape]

This is a player loadout

Upon pressing a button it equips the next item in the array, wraps around to start when reaches end

Selection is determined by an int pointing to offset in the list

And this has to be persistent for every player because duh

Items of loadout are created serverside ('cause it's a set of actors that replicates) and therefore needs to be replicated

[fathom aspen]

Well array order is preserved on server and client if that's what you ask.

What you're looking for is an inventory system and by looking through this channel search you can find a plenty of examples

[steady cape]

That's.... not true, to my memory

But alr, I'll recheck

[steady cape]

And it would already be working if it wasn't for RPC misuse from my side

[fathom aspen]

It's true. FastArrays don't preserve order for example but that's another topic

[steady cape]

I'll check and report later

[thin stratus]

Has anyone lately dived into making a Leap ability with GAS not end in correction-hell from the CMC?
Lyra uses RootMotionSource, but on Emulated NetSettings even Lyra gets tons of corrections (which is again super sad given this is supposed to be a proper example).

Or generally abilities with movement...

Why is this always such a pain with UE

Everything that doesn't go through ServerMove is just crap. And it seems like corrections hit super hard with RootMotionSource stuff

[thin stratus]

The only way I get this smoothly working is by ignoring client corrections until before performing the RootMotionSource and reenabling it with a Sync Node so both have perfomed the leap

[twilit radish]

I may be wrong but didn’t Lyra just massively speed up acceleration as their “dash”?

[thin stratus]

Na they have a GA Dash with a RootMotionForce

And an RPC inside that, they just didn't care I guess

[twilit radish]

Ah alright.

It's confusing though because ALyraCharacter and ULyraCharacterMovementComponent both do stuff with replicating custom acceleration 🤔

But I guess that's for something else then.

[thin stratus]

Yeah not sure

Might be for animation matching or so

[twilit radish]

Also, Cedric. Do you know how the CMC prevents speed hacks? I'm trying to better understand how the code in general works every now and then but every time I look at it I keep wondering what prevents people from doing stuff like that 🤔

All it seems to do to me is that it just limits the max delta time it calculates based off a client time stamp. But what is preventing me from sending a bunch of movement packets to 'simulate' high FPS games and then setting my client time stamp to look as is if it reaches that max every time on thus a high incoming rate?

[pallid mesa]

the corrections should be minimal under no hazardous conditions, could get good results under the 150ms mark

[thin stratus]

Hmpf...

[pallid mesa]

hahaha xD I know

[twilit radish]

The wonderful world of MP 😛

[pallid mesa]

works for dashes, leaps and such, other than that... might revisit the CMC, again, corrections should be almost non existant unless there are discrepancies

[thin stratus]

I used to make dashes by literally programming them into the CMC

But that was for games where you just had that one dash

Not a bunch of GAs that could all move you in different ways

[pallid mesa]

it just works, but programming a dash onto the cmc is a show

[thin stratus]

Yeah I flex with that when meeting the ladies

[pallid mesa]

yeah indeed specially with grandeous stateful systems

x'DDD

[thin stratus]

I just know that modifying the CMC state from outside is causing correction.
Changing movement speed via the GA (via some GE in the end that drives a speed attribute) is somewhat okay

The correction is invisible

But everything else feels like the wrong setup

[twilit radish]

Also different question. Is it possible to link the client time to the server time? So know when at a given point in time on the client what the server time is? The current system from Unreal is rather weird and suffers from latency :p

[thin stratus]

I asked that before to link up some timer

But I can't recall what the result was

I think I just sent a timestamp or so

Or wait

People said to just end the future timestamp

[pallid mesa]

yes

hang on, for you

[thin stratus]

So if you have a timer of 10 seconds, just talk about it in terms of CurrentTime + 10.
Then Server and Client show it correctly

[twilit radish]

But what if the client's PC time is out of sync?

[thin stratus]

If you just use the replicated server time, it will get in sync eventually

You can also do what vori posted

[pallid mesa]

but the gamestate server time is inaccurate

most of the time is enough

[thin stratus]

It is enoug hfor most things yeah

[pallid mesa]

this one is more precise except for the first 10 seconds

[thin stratus]

If you play some random AAA game, you notice that the timers never exactly work

Respawn countdowns for example are always off by some degree

[pallid mesa]

clockos are hard

• duck

[twilit radish]

xD

[thin stratus]

I think that falls under MP is hard

But you might be able to show that code snippet to the ladies

Or boys, fwiw

sigh Can't wait to get the office tomorrow to fix Movement Corrections caused by RootMotionSource in a GA that I didn't code and inherits from 3 freaking parent GAs (chain)

[twilit radish]

😅

[pallid mesa]

you are a beast, you'll get it working

[steady cape]

So I checked and it seems like you're right - it does preserve the order

Looks like I've been mislead by some other source about this

Big thanks for opening my eyes

[winged badger]

it can happen but its not guaranteed

[dark edge]

@twin juniper move it here

OK so what's the design, replicated airplane movement?

[twin juniper]

good choice

[twin juniper]

in short, yes -- there's a replicator component and the for prototyping purposes the movement is not segregated into its own comp, so it's on the pawn descendent

[dark edge]

Are you trying to use physics or are you doing flying on your own?

You said simulating physics on a skeletal mesh so I'm thinking physics but what is actually doing the flying mechanics?

[twin juniper]

please describe this

void AFlightReplicationEntityPawn_Master::SimulateMove(const FVehicleMove& Move)
{
    const auto UpdateLinearVelocity = [this, &Move]()
    {
        EntityPawn_CurrentThrottle = FMath::Clamp(Move.CurrentThrottle + EntityPawn_ThrustValue,
                                                  -MaxThrust, +MaxThrust);
        const FVector TargetLinearVelocity =
            RootEntityBody->GetForwardVector() * (Move.CurrentThrottle * Acceleration * Move.DeltaTime) + GravityVector;
        EntityPawn_CurrentLinearVelocity = FMath::Lerp(
            RootEntityBody->GetPhysicsLinearVelocity(), TargetLinearVelocity, InterpolationConstant);

        RootEntityBody->SetAllPhysicsLinearVelocity(EntityPawn_CurrentLinearVelocity);
    };

    const auto UpdateAngularVelocity = [this, &Move]()
    {
        EntityPawn_CurrentAngularVelocity =
            -RootEntityBody->GetPhysicsAngularVelocityInDegrees() / AngularVelocityScalar * Move.DeltaTime
            + Move.ForwardVector + Move.RightVector + Move.UpVector;

        RootEntityBody->AddTorqueInDegrees(EntityPawn_CurrentAngularVelocity, NAME_None, true);
    };

    UpdateLinearVelocity();
    UpdateAngularVelocity();
}

that's your answer

[dark edge]

So it looks like you're simulating physics but NOT using physics to do the actual forces and torques, it's a weird setup but it can work i guess.

[twin juniper]

USTRUCT()
struct FVehicleMove
{
    GENERATED_BODY()

    // Perceived time-slices from every client Tick
    UPROPERTY()
    float DeltaTime;

    // Timestamp from when move began
    UPROPERTY()
    float StartTimestamp;

    // Per tick:

    UPROPERTY()
    float CurrentThrottle;

    UPROPERTY()
    FVector_NetQuantize100 ForwardVector;

    UPROPERTY()
    FVector_NetQuantize100 RightVector;

    UPROPERTY()
    FVector_NetQuantize100 UpVector;
};

[twin juniper]

it does work, surprisingly
I did the math too, it makes sense

[dark edge]

You're directly setting velocity but using torque for orientation

You should choose one or the other IMO. I'd prefer using forces and torques but it's up to you.

[twin juniper]

Can't, not in the requirement

[dark edge]

Anyway, have you looked into the physics replication stuff? This can just work in multiplayer out of the box, depending on if you need prediction or not. For slow-responding things like airplanes, waiting 30ms for a response from your input is fine.

[twin juniper]

I have not.

[dark edge]

That's a wacky ass requirement if they want to directly override physics velocity but not physics rotation

[twin juniper]

Well the code looked way worse before what I did

[dark edge]

I'd hate to see it lol

[twin juniper]

the AngularVelocity was not even factoring in DeltaTime earlier

[twin juniper]

we need smooth movement on clients

that's the only thing I'm being tested for

(it's an unofficial hiring test)

[dark edge]

Torque doesn't need DeltaTime brought into it but that logic right there is a clusterfuck

[twin juniper]

I scoured the source to find where that hidden dt comes in but found none, hence why I replaced a magic number with what's there

so how will we ever get rid of that warning

I'm unable to test it properly because UE5 is set to lag if it's not in focus

fixed that, testing

oh no it's a mess I must sleep over (before midnight here)

[dark edge]

That entire architecture seems like a mess but the high level overview of how I'd do physics driven flight is like this

Tick -> Send input to serverside -> Calculate forces -> calculate torques(might not be necessary, depending on flight model) -> Apply them

The physics replication settings can keep the clients smoothly in sync with the server.

[twin juniper]

this is the movement side, yes?

this is pretty much exactly what happens btw

void AFlightReplicationEntityPawn_Master::BeginPlay()
{
    Super::BeginPlay();
    
    GetWorld()->GetPhysicsScene()->OnPhysSceneStep.AddLambda([this](FPhysScene*, const float FixedDeltaTime)
    {
        if (GetLocalRole() == ROLE_AutonomousProxy || GetRemoteRole() == ROLE_SimulatedProxy)
        {
            LastMove.DeltaTime = FixedDeltaTime;
            LastMove.StartTimestamp = GetWorld()->GetGameState()->GetServerWorldTimeSeconds();
            LastMove.CurrentThrottle = EntityPawn_CurrentThrottle;
            LastMove.ForwardVector = EntityPawn_RollResultantForwardVector;
            LastMove.RightVector = EntityPawn_PitchResultantRightVector;
            LastMove.UpVector = EntityPawn_YawResultantUpVector;

            SimulateMove(LastMove);
        }
    });
}
...
void AFlightReplicationEntityPawn_Master::SimulateMove(const FVehicleMove& Move)
{
    const auto UpdateLinearVelocity = [this, &Move]()
    {
        EntityPawn_CurrentThrottle = FMath::Clamp(Move.CurrentThrottle + EntityPawn_ThrustValue,
                                                  -MaxThrust, +MaxThrust);
        const FVector TargetLinearVelocity =
            RootEntityBody->GetForwardVector() * (Move.CurrentThrottle * Acceleration * Move.DeltaTime) + GravityVector;
        EntityPawn_CurrentLinearVelocity = FMath::Lerp(
            RootEntityBody->GetPhysicsLinearVelocity(), TargetLinearVelocity, InterpolationConstant);

        RootEntityBody->SetAllPhysicsLinearVelocity(EntityPawn_CurrentLinearVelocity);
    };

    const auto UpdateAngularVelocity = [this, &Move]()
    {
        EntityPawn_CurrentAngularVelocity =
            -RootEntityBody->GetPhysicsAngularVelocityInDegrees() / AngularVelocityScalar * Move.DeltaTime
            + Move.ForwardVector + Move.RightVector + Move.UpVector;

        RootEntityBody->AddTorqueInDegrees(EntityPawn_CurrentAngularVelocity, NAME_None, true);
    };

    UpdateLinearVelocity();
    UpdateAngularVelocity();
}

[dark edge]

That's a bit different, that's sending moves to the server, not controls

[twin juniper]

Ah, the moves are sent to the server in the replicator

[dark edge]

I'm talking about sending controls to the server.

[twin juniper]

intriguing, directly sending the controls?

[dark edge]

Yes or some derived data based on the controls. For my project, that's throttle, brake, steering angle, etc.

Mine's land vehicles though

[twin juniper]

void AFlightReplicationEntityPawn_Master::SetupPlayerInputComponent(UInputComponent* PlayerInputComponent)
{
    Super::SetupPlayerInputComponent(PlayerInputComponent);

    PlayerInputComponent->BindAxis("Entity_Thrust", this, &AFlightReplicationEntityPawn_Master::OnEntityThrust);
    PlayerInputComponent->BindAxis("Entity_Yaw", this, &AFlightReplicationEntityPawn_Master::OnEntityYaw);
    PlayerInputComponent->BindAxis("Entity_Pitch", this, &AFlightReplicationEntityPawn_Master::OnEntityPitch);
    PlayerInputComponent->BindAxis("Entity_Roll", this, &AFlightReplicationEntityPawn_Master::OnEntityRoll);
}
...
void AFlightReplicationEntityPawn_Master::OnEntityThrust(const float ThrustValue)
{
    EntityPawn_ThrustValue = ThrustValue;
}

void AFlightReplicationEntityPawn_Master::OnEntityYaw(const float YawValue)
{
    EntityPawn_YawValue = YawValue;
    const FVector TargetVector = RootEntityBody->GetUpVector() * (EntityPawn_YawValue * YawRate);
    EntityPawn_YawResultantUpVector = FMath::Lerp(FVector::ZeroVector, TargetVector, InterpolationConstant);
}

void AFlightReplicationEntityPawn_Master::OnEntityPitch(const float PitchValue)
{
    EntityPawn_PitchValue = PitchValue;
    const FVector TargetVector = RootEntityBody->GetRightVector() * (EntityPawn_PitchValue * PitchRate);
    EntityPawn_PitchResultantRightVector = FMath::Lerp(FVector::ZeroVector, TargetVector, InterpolationConstant);
}

void AFlightReplicationEntityPawn_Master::OnEntityRoll(const float RollValue)
{
    EntityPawn_RollValue = RollValue;
    const FVector TargetVector = RootEntityBody->GetForwardVector() * (EntityPawn_RollValue * RollRate);
    EntityPawn_RollResultantForwardVector = FMath::Lerp(FVector::ZeroVector, TargetVector, InterpolationConstant);
}

here are the controls per se

[twin juniper]

derived data is precisely what's sent as moves

maybe the nomenclature is whacky because of gamedev.tv influence

[dark edge]

The throttle is a control variable, the 3 vectors are the results of some sim unless they're meant to be a control variable.

[twin juniper]

they look like control variables for "heading"

[dark edge]

If it's desiredheading that's fine

if it's simulated heading then that's weird, it's mixing controls and results together

[twin juniper]

the values called "yaw, pitch, and roll" here are actually just Throws, so they scale a rate and change the direction by influencing each axial component of the heading vector

(afaik)

[dark edge]

But anyway, the physics replication system can do the heavy lifting of keeping things smooth for you, assuming the physics movement is what's considered the canonical end result. I'd dig into those settings, there's a ton of tunable parameters.

[twin juniper]

Please point me to the docs, I'll look into them in the coming week after I fail to make this example work within Saturday

[dark edge]

My project has buildable land vehicles and the basic system is exactly what I outlined and it works perfectly. The only downside is there's NO lag compensation, but lag compensation in physics is horrendously complicated.

[twin juniper]

I believe we are indeed looking for lag compensation when we talk about smooth movement

unless I misunderstood that requirement because of my inexperience

[dark edge]

There's a difference

lag compensation is when you press jump in a game and you jump instantly on your screen, with the server still being authoritative

it's HORRIBLY complicated for physics driven movement

[twin juniper]

it's desired heading, based on my preliminary squint on the code

[twin juniper]

oh, maybe not that then

[dark edge]

Watch the GDC talk on Rocket League networking if you want, but anything with prediction is totally overkill for an airplane game. Airplanes don't respond that quickly anyway.

[twin juniper]

well I'm on a less wrong path then

I'm still not able to turn off that warning

[dark edge]

These are the tuning settings I was talking about

Read the source code on them, it's pretty much the only documentation

The stock settings are pretty strict

Like you don't care if an airplane is within 1cm of where it should be

[twin juniper]

Yeah I know about these

afaik there was also some random error which crashed the engine when I wasn't looking

I will seriously consider sleep now. There's a whole IRL to deal with outside this multiplayer sample.

[pallid mesa]

oh movement replication!

really good luck with that 😄

[regal geyser]

What is the smart way of synchronizing all created teams by server (When player connects he is assigned a random team inside GameMode)?

My approach was to change RepNotify variable inside GameState with all created teams, and when new team is added to the array, every client would be notified. The issue is that I need to update HUD of all clients to display all currently created teams. But I'm not sure how I can access local player and his HUD component from inside of a GameState RepNotify event.

[thin stratus]

Two ways

Either you ensure that your HUD is easily accessible e.g. via the PlayerController

So you can just get the PC and access the HUD in the GameState

Or

You add a delegate/event dispatcher to the GameState

And bind/listen to that in the UI

Which is what I would do

[regal geyser]

Thank you! Okey I'm going to try the latter but just out of the curiosity, how can I get local PC inside of a GameState?

Tried using get controller and cast it but that failed

[thin stratus]

GetPlayerController should work fine

[regal geyser]

With 0 as default index? It says it should be local player but I've read multiple times that this doesn't have to be true sometimes when connecting to server

[thin stratus]

For a local player it will be correct

They only have their own PC anyway

ListenServer should also get their own with thay

[regal geyser]

Yes thats what I thought so, okey thanks a lot for help!

[dawn delta]

If I switch to source engine build on 1 machine to build dedicated servers, do I need to do that on all workstations to maintain multiplayer compatibility?

[nova wasp]

or you could just distribute the packaged build?

or package the engine itself to save some time

unsure if it will consider it a different version, my assumption is yes

[dawn delta]

ya, just tested and it considers it a different version. I didn't want to have to have source on all workstations for quick testing, but maybe thats best way.

was saving packaging/distribution for bigger testing runs

[nova wasp]

distributing your engine build should not be too difficult

as that will change less often than your game project, I assume

[dawn delta]

What I really want is to connect to the server via PIE. That works with the PIE that is source built. That doesn't currently work with the PIE that is not source engine built.

[twin juniper]

Please remind me how I must set up my pawn to make use of these settings.

[dark edge]

Those settings cover how replicated physics behave

[twin juniper]

So I can just focus on the movement logic and not worry about the rest at all, right?

Could you provide me a sample under 1-2 KLOC which shows a vehicle being replicated over a network? CMC is way too big and covers a totally different beast in my eyes.

[nova wasp]

huh?

well, I guess there's smoothsync

[twin juniper]

Could you please elaborate? I kinda need this asap!

[nova wasp]

https://www.unrealengine.com/marketplace/en-US/product/smooth-sync

https://developer.valvesoftware.com/wiki/Source_Multiplayer_Networking#Entity_interpolation

they base it off of the source engine movement replication

[eternal canyon]

tho smooth sync is also client auth

[nova wasp]

ruh oh

nevermind then 😅

[eternal canyon]

from what i remember the person plans on making a server auth version

at some point

[nova wasp]

at the very least one could yoink the interpolation I suppose

[twin juniper]

https://youtu.be/cdmzd3v3W-o

I've wrecked the code by trying to gamedev.tv myself into this. I'm not yet fit for a multiplayer based job I guess.

I'll ask for permission from my in-charge to share the code repo.

[twin juniper]

my would-be employers have that plugin on their systems

[nova wasp]

well, as mmmm says it's not authorative out of the box

but I suppose it would be a nice thing to study

certainly beats the default interpolation

[twin juniper]

the problem we're dealing with has a domain far surpassing our needs and understanding of it

[nova wasp]

...is this even a competitive game?

[twin juniper]

yes, it's meant to be a 5v5 team deathmatch

obviously it sucks arse rn

I mean I made the gameplay worse than what my in-charge gave me

[nova wasp]

I guess my point would have been to maybe just half ass it and go client side movement if it was pve

[twin juniper]

I'll let you read the repo

[nova wasp]

I don't have time to read it and I'm really not an expert here, I'm just saying what I would try first

here's another massive list of stuff to read lol: https://gafferongames.com/

[twin juniper]

okay, so TL;DR it's server auth

[twin juniper]

I removed the replicator
alas

[tiny anchor]

What's a good way to attach an item to my character's hands and have it properly setup for FPS, while having it correctly set for others to see (multiplayer)?

[twin juniper]

https://github.com/neosphereinteractive-real/FlightReplication/tree/dev-vivraan-fix-rep

This is the code I have atm

Any understanding I can gain on the project wrt this code will be deeply appreciated.

[twin juniper]

best read CMC for this, although I believe they don't handle guns as attached actors

[tiny anchor]

Do you mean Character Movement Component?

I don't understand how CMC could help me there 🤔

[fathom aspen]

You attach it to the wanted socket on character and you make sure you're doing that on server and it magically replicates

[tiny anchor]

Alright I think I need to reformulate my question. How can I attach my item to my FPHands (only owner sees), and have it also attached to TPMesh (owner no see)? Said item can be "dynamic", it can be a smartphone with a screen which can been seen by both the player it's attached to, and others players, so its behaviour needs to be replicated

[fathom aspen]

You literally said what you want. You already have FPHands set as OnlyOwnerSee, and I think any attached actors to that mesh will have the same behavior(if not you do it explicitly). Same goes for TPMesh you have it as OwnerNoSee and you attach that item to it and you get same behavior

The functions you need to know are literally SetOwnerNoSee, SetOwnerOnlySee

That's at runtime

Or you do it in details panel

[tiny anchor]

So is it only one item, or do I need to duplicate it?

[fathom aspen]

You can't have same item attached to two different meshes

So the answer is yes

[tiny anchor]

Oh alright, that makes sense

Thank you very much

[twin juniper]

@ebon cape

[twin juniper]

Repo is now public

[eternal lake]

Hello there! 😄

AController::Pawn is set to REPNOTIFY_Always.

Will this cause Listen Servers to receive an OnRep call when changing the value (on the listen server)?

[violet sentinel]

no, call onrep in mutator explicitly if you want it on server too

[eternal lake]

Cheers

[faint gust]

I’m having an issue where animations are not played on the other client on the server how would I go about fixing this

[chrome bay]

REPNOTIFY_Always essentially means "always call the onrep, even if the local value is the same"

It's commonly used when clients are modifying replicated variables (which is usually a big no-no, but sometimes neccesary)

And because the whole controller->pawn replication is a complete mess

But Epic dare not touch it these days

[twin juniper]

Any help here?

[twilit radish]

What's the issue with it?

[twin juniper]

It's become much worse than when I didn't meddle with it. I implemented a Replicator comp which sadly makes things much worse.

[twilit radish]

But what's the issue in the first place?

[twin juniper]

We're trying to implement a semblance of smooth replication of simulated proxies.

My code is quite amateur and doesn't exactly do the job right.

[twilit radish]

It kind of depends on what you want to achieve I suppose but from what I see a lot of games just take the approach of having a small buffer of locations and then working their way through that with a lerp for example or some different smoothing algorithm. There are definitely other techniques like extrapolating which you can do if you want but just using a lerp with a buffer does the job most of the time good enough.

It's a bit difficult to know for us how to exactly apply that to your code though. Which is also mostly up to you I would say 😛

Valve has a small page about it you could also look at: https://developer.valvesoftware.com/wiki/Source_Multiplayer_Networking
Not sure how up to date it is though. There's a section called "Entity Interpolation".

[eternal lake]

I figured that part, however that made me question that maybe the fact listen servers don't receive an onrep is because they've already changed the local value, so it's (technically) "the same" as the server value

[chrome bay]

Ah no, in C++ world RepNotifies are only called client-side, since they are "receiving" the value. Blueprint rep notifies are a giga-hack

[static sable]

hi, I have my server actor controlled by a behavior tree. Using my playercontroller I send a move command to that actor.

But when that actor turns, it's very choppy, because only the data that come from the server update the actor's location/rotation. I would like to run a local instance of behavior tree on client actor so it updates client actor accordingly and sever eventually just corrects the actor's location/rotation.

How to do it since there is no controller associated with the client actor therefore client actor's behavior tree doesn't even start?

[quasi tide]

Curious - what makes it a complete mess?

[pallid mesa]

xD

[faint gust]

i have this respawn code witch works fine in singleplayer but in multiplayer it dosnt and i have tried to get the controller from the player input but it just causes an error

[rapid bronze]

Don't multicast a spawn

Only RoS

Plus you using PlayerController0

[faint gust]

yeah and i dont know how to get the number of the player that died

[rapid bronze]

No need for a number

You can just pass the controller ref of the one who died

It just depends on how you have it all setup

And where

[fathom aspen]

Read this please: #multiplayer message

[normal quartz]

still new to networking myself, but i believe its because controllers aren't replicated, so everyone's own controller including the server is index 0 as far as they know, it's used for local splitscreen multiplayer, which is why you need the ref

[faint gust]

im running it like this would i get the ref with get controller and put it there?

[rapid bronze]

No, on a server Index 0 is the first player

Locally it's always yourself

Where is that

In what class

[faint gust]

the player class

[fathom aspen]

You are calling an RPC in the GameMode while it exists only on the server

[rapid bronze]

The GM may not even be accessed

GameMode can only be called on server

[faint gust]

ahh

so the etire system dosnt work with MP

[rapid bronze]

Read the compendium

[normal quartz]

but maybe that explains what i'm missing about how controllers work here - this spawn stuff in the game mode works for everyone except the server. if i run a server and 3 clients and i put a print string here, i get four hellos, but the server never gets a pawn or a UI, and the first client (the second one to join, so should be index 1 in that array) spawns at spawn tag 0.

what's in the screenshot is almost exactly the same as a video tutorial i followed and it works there

[rapid bronze]

If needed, GetPlayerController is good to get all players in the GameState

GameState has an array of PlayerStates that you can iterate and use the index of that in GetPlayerController to iterate all controllers

Alternative that storing everyone in the GameMode OnPostLogin

[fathom aspen]

I'm not sure why you're using a SwitchHasAuthority. You're in the GameMode i.e, server only

[faint gust]

ok what im not understanding is how to request the server to do anything if gamemode is only on the server and i dont know how it would even be posible foe be to do this

[rapid bronze]

We talking Listen sever or Dedi here?

[rapid bronze]

Run it on the server?

[fathom aspen]

You route RPCs only through PlayerController/PlayerState/Pawn

[normal quartz]

appreciate pointing that out, just copied from the tutorial and while troubleshooting if something doesn't fix it i change it back to keep track of things :D but that shouldn't ever return remote anyway, right

[fathom aspen]

You got reference to some of those thorough the GameState for example

[faint gust]

but how would the server know how the player died im sorry im being stupid

[rapid bronze]

RPC

[normal quartz]

listen

[faint gust]

what is RPC

[rapid bronze]

But I mean, the player shouldn't tell the server how it dies anyways

Server gotta know

[fathom aspen]

Yes that's wouldn't change anything. And I'm not even sure how you add widgets and stuff

But the tl;dr for you should be don't follow tutorials

They are your worst enemy

Read the compendium if you haven't got to do so

[rapid bronze]

Always understand what you're doing if you plan to follow a tutorial so you know when they do something wrong

Blindly following will only cause problems

[fathom aspen]

Remote Procedure Call

[normal quartz]

coming to realise this :D and I just add widgets by casting to the player controller and calling an event. but it never gets to that point because the server never gets added to that array

[faint gust]

ok so i shouldnt trust the client telling the server hey respawn me right

[fathom aspen]

Well you shouldn't be making an array anyways

[rapid bronze]

Never trust the client

[fathom aspen]

Read this

You got PlayerArray in GameState

[faint gust]

right so i need an event to know when somthing gets destroyed

[fathom aspen]

It's already handled for you client and server side

[normal quartz]

i'll certainly swap it over to that logic, i guess i just wanted to know for future reference what the problem here was if possible. thanks a bunch all for the help

[fathom aspen]

No worries. PlayerArray is an array of PlayerStates. To get the PlayerControllers, you do GetOwner on each PlayerState element

[faint gust]

what do you mean its already handled like in what way

[fathom aspen]

It's synced

Though it's not replicated

[faint gust]

ok so the server has all player states correct

[fathom aspen]

Correct

[faint gust]

so i can loop through all players checking for it being destroted corredt

[fathom aspen]

Well that's obviously not the way you would do it

[rapid bronze]

Wha

[fathom aspen]

How do you know if a player died?

Think about it?

He gets damaged for example and then you check health on server and if health is below or equal zero then he's dead

[faint gust]

so i check for death conditions instead of just death

[fathom aspen]

Correct. You make your functions fire on events

Player died -> do this

Not: check on tick if player died then do this

That's what is called event driven code

[rapid bronze]

Since it's always ran on server, everytime you take damage check if health below equal 0 aka you died, if true you can run a HandleDeath event, even on the GameMode if you have a common death function handle

[faint gust]

the thign is the only death condition is falling off the world what event would i use for that

[rapid bronze]

So you don't have health and such? The only thing that can happen is getting destroyed?

[faint gust]

there is no health currently

im working on other stuff right now

[fathom aspen]

There's an event for that by they way

FallenFromWorld?

[rapid bronze]

FellOutOfWorld iirc

[fathom aspen]

https://docs.unrealengine.com/4.27/en-US/API/Runtime/Engine/GameFramework/AActor/FellOutOfWorld/

[faint gust]

is there a version for blueprint or would i have to make a c++ accsessor

[fathom aspen]

Nope

But you don't need it to be exposed

You can have a some volume under your level

That does that collision handling for you and acts accordingly

[faint gust]

and have a BP on the volume that when its touched it runs an event on the gamemode

[fathom aspen]

Well you already have an event called HandleDeath or OnDeath, so you access the GameMode from that actor and call it

Or call the interface function that does the death, and then OnDeath is called automatically

Plenty of ways really

[faint gust]

what?

i dotn see an event on the gamemode for death

[fathom aspen]

You make it 🙂

It's game specific

But it should have a point where you call Destroy for some stuff

[faint gust]

ok so i would make the volume make the gamemmoe run that function right?

[fathom aspen]

Yes

[faint gust]

so what kind of voume should i make?

there are ALOT

[rapid bronze]

Volume overlaps player, you get mister player from the overlap, you run the death function through the GM

Box volume

[faint gust]

i dont see a box volume

[rapid bronze]

You have to make a BP

[faint gust]

ahh

[rapid bronze]

Then add it

[faint gust]

box collision right

[rapid bronze]

Yea

[faint gust]

so i just make a cube and scale it right

[rapid bronze]

Yeah

How UE handles it is that it checks if you are under a certain Z but you don't have to do that

[faint gust]

should i make it thick so it things dont phase though it

[rapid bronze]

I mean sure

[normal quartz]

in case it helps anyone else, got the logic switched over to using the game state's array, but the issue was the timing; i was collecting the Player Starts on BeginPlay and the server was logging in too quickly before it was done 🙃 made sure that step was done before trying to spawn anyone

[faint gust]

like this right?

it works 🎉

[twin juniper]

I have already done that. You may examine my Replicator code.

Also please ping me as I'm not frequenting the channel.

[sinful tree]

This is not a good way to do it. What you've done is open a means for players to teleport around the map whenever and wherever they want to as you're allowing the client to tell the server that they want to teleport and the destination.
The "BeginOverlap" event that triggers your code should be already running on the server - all you should need to do is use a "Has Authority" switch and use the "Authority" path to connect with your existing code, and you can then remove the "Run on Server" part from your "Respawn Player" event.

Correcting as I've suggested will mean that only the server will ever check what is happening on the overlap and determine what to do next instead of relying on the client to tell the server to respawn the player and where to move that player to.

[faint gust]

the overlap is on an object that is not the player ansd i should add an authority to the teleport right

[sinful tree]

The idea of the authority switch is you're checking if the current instance of the game has a certain level of permission over the object. The "Has Authority" should be placed immediately after your "OnBeginOverlap" event.

[faint gust]

done! so that should fix it right

[sinful tree]

Yes, but also make sure to change the "Respawn Player" event. It shouldn't use the "Run On Server" option.

[faint gust]

what should it use?

[sinful tree]

Whatever the "None" option is. The event should just run, doesn't need to be an RPC.

[faint gust]

👍

[sick acorn]

Hello, I have an object in the game that rotates. this is a simple square 50 by 50 by 1 meter, and when I'm on it, the stob pulls me from the old side to the side ...

The closer I am to the pivot of the component, the less jerks how to fix it?

[dark edge]

"the stob pulls me from the old side to the side"
what

[sick acorn]

when I stand on this actor it twitches me

understand ?

I really need to know why this is happening.

[dark edge]

You are getting movement corrections because the client and server don't agree on the movement. Welcome to multiplayer.

[sick acorn]

no, I have 2 objects server and client move the same way

i use the simplest sync code

[dark edge]

Show your code. Are you using the CMC or no?

[thin stratus]

It might make more sense to AddWorldRotation instead of setting it and it utilize DeltaSeconds instead of WorldTimeSeconds

Has anyone checked the progress on the NetworkPredictionPlugin lately?