multiplayer

[grizzled stirrup]

Yep, that'll be very nice

As CMC is extremely expensive / bloated

It works great though

[zealous saffron]

yeah

[grizzled stirrup]

But could be much cheaper for AI etc.

[worthy perch]

Probably new NavSystem too.

[chrome bay]

I don't think the prediction thing will make it much cheaper tbh, they're still only planning to use it for player-controlled stuff

[zealous saffron]

it really should have a PMC then PawnNetworkedComponent -> CMC

[chrome bay]

But it'll make making non-CMC predicted movement a buttload easier

As it separates the networking layer from the simulation layer

Which is the most important bit

[grizzled stirrup]

Right now it's all intertwined right? Capsule / character / cmc

[zealous saffron]

it's somewhat of a mess

[chrome bay]

It is, but the problem is more that the networking side of CMC is closely tied to the simulation

[zealous saffron]

yep

[chrome bay]

So you can't easily adapt it for something else

In the case of my vehicles, I basically rewrote most of CMC's approach - but adapted it to be able to run different simulations

[zealous saffron]

it works fine for a prototype but past that you have to invest in taking the useful networking and simulation into your own class.

[grizzled stirrup]

Interesting. Yeah I have some cases where a capsule doesn't fit the shape of a charater very well and it results in movement not looking / feeling as good as it could

[zealous saffron]

or having a vertical capsule represent a ship 😐

[chrome bay]

I was using one skeletal mesh component as the root for mine

No proxies, just offset the render matrix for smoothing

sort of worked

But has limitations

[sleek current]

Hey is there a guy who knows how to do things the right way in multiplayer C++ and is willing to help a noob out xd?

[fleet raven]

there are many such people here, that is the point of this channel

[grizzled stirrup]

Better to ask a specific question and people can help out 🙂

[twin juniper]

how can i debug

where the server thinks my pawn is

and where the client thinks it is

[sleek current]

@fleet raven Yeah but I have a question about my whole pc class like how to do it right way in C++ for multi 😛 and I think that it's too much and it would be a spam so I asked if I just could pm someone 😛

[sleek current]

Aight so I have a pc that should call on it's players functions related to input in beginplay() I have this line void AFarmTaskPlayerController::BeginPlay()
{
Super::BeginPlay();

Character = dynamic_cast<AFarmTaskCharacter*>(UGameplayStatics::GetPlayerCharacter(this, NetPlayerIndex));

}

For every player that has index != 0 it returns null in AFarmTaskCharacter

Anyone knows why ><?

[fleet raven]

the character does not exist at that point

you should always use Cast not dynamic_cast

[sleek current]

Why?

[fleet raven]

because that's what you use in unreal

also looks nicer

for the character not existing, check out how the process of joining works in game mode base::login

[sleek current]

It still fires NULL and that's not really a good argument if unreal wouldn't support dynamic cast then he would just remove it from unreal framework

[fleet raven]

it first creates a controller, then later, it will create a character for it, then possess it

[sleek current]

So what methods should I use to make it right?

[grizzled stirrup]

Is it fine to call Server RPCs on the server as regular functions? Instead of having to do

if (Role == ROLE_Authority)
{
   CoolFunction();
}
else
{
   ServerCallCoolFunction(); // calls CoolFunction() on the server
}

I'd instead do:

// Regardless if client or server calling this
ServerCallCoolFunction();

That way I could simply put the contents of CoolFunction into the RPC and save many lines of code

[fleet raven]

yes, calling a server rpc on the server will execute it locally as expected

[grizzled stirrup]

Thanks!

Makes life much easier

[sleek current]

So are there methods/variables that tell me when pawn is possessed by a certain controller?

[grizzled stirrup]

OnPossessed() / PossessedBy()

Those are called on the controller / character and can be overriden to do things

[sleek current]

void AFarmTaskPlayerController::OnPossess(APawn* InPawn)
{
Character = Cast<AFarmTaskCharacter>(UGameplayStatics::GetPlayerCharacter(this, NetPlayerIndex));
}

It doesn't shoot NULL now since I made if that check whether or not character is NULL on every method that calls movement/action on a player

But it doesn't spawn my player mesh and the actions only work on server

What am I doing wrong?

[chrome bay]

Why not just use the pawn being passed into the function?

You can get the pawn directly from the controller, there's no need to go through gameplay statics to get it

[sleek current]

True, did that. But still there is a problem that my mesh is not spawning and the functions dont work on pawn

[chrome bay]

Impossible to say why really without having the code in front of us

[sleek current]

You got in on pm

[chrome bay]

I can't help atm, am working

Even so can't go through all your source code 😄

[grizzled stirrup]

If you pass a regular FVector into a function that takes const FVector_NetQuantize& will it be correctly quantized or should I remove the &?

[twin juniper]

https://www.youtube.com/watch?v=cnhbdIp8AN4&feature=youtu.be

what is up with the jittering

[thin stratus]

Looks like you are adjusting speed on only client or server.

[sleek current]

How can I make fpp projectiles replicated so I can see them on each client and server?

Tried RPC server, client and multicast and probably did something wrong ><

[twin juniper]

@thin stratus someone said to send the multicast event or the server event on a client replicate and set the location there

did i got that right?

[thin stratus]

@sleek current You need mark the projectile replicated and then let the Server spawn it by forwarding the fireweapon stuff via ServerRPC

@twin juniper Ehm not sure what exactly you mean :P

If someone suggested you something then you should make sure you followed their instructions properly

[twin juniper]

im doing this right now

is this okay?

[thin stratus]

Not really

1. You don't need to pass the Component, it exists on each instance anyway.
2. Where does that call come from? Tick? If so, then you need to have someone be the Authority over this.

[sleek current]

I used server, reliable and the projectile is breplicated true

[thin stratus]

E.g. if the Clien should have Authority (not the greatest idea), then you would need to let the Client send the location via RPC and then let the Server send it via Multicast.

BUT

You need to make sure that the Multicast is filtered for the owning client

[sleek current]

it only works on server I mean I only see and hear on server

[thin stratus]

Otherwise you override the location again (rpcs take time after all)

[twin juniper]

is there any network sample projects

[thin stratus]

@sleek current Not sure then, this is pretty basic stuff. You might want to go over everything once more.

@twin juniper Yeah more or less, but nothing that does this I would guess.

[sleek current]

UFUNCTION(Server, Reliable)
void OnFire();

[thin stratus]

Mostly cause movement is done a bit different

[twin juniper]

im doing movement through physics

so instead of replicate physics im replicating the location and rotation

[chrome bay]

It's never going to work if the Server is replicating the positions back to you

Networked physics has to be client-authoritative in order to work.

Server-auth is pretty much an unsolvable problem

[twin juniper]

im not networking physics cause i did that and it was a big mistake

[chrome bay]

You said you're doing movement through physics

[sleek current]

Alright so I made it work, actually the blueprint needed to change replication(it sucks that c++ even in constructor doesnt change values in already created blueprint) but all thats left is sound, it only plays on server any idea?

[chrome bay]

If the object is simulating physics, it's using the physics engine

[twin juniper]

the physics engine is replicating?

[chrome bay]

No, it doesn't work that way

The physics engine is constantly simulating on both machines. By the time the server told you what's happened, it's already too late

You will constantly be being snapped back in time when using server-auth

[thin stratus]

@sleek current Well it doesn cause you aren't modifying the BP

You are modifying the C++ parent

If the Constructor change would adjust all child BPs that would be shitty annoying

[twin juniper]

thats whats happening to the video i guess

so what do i do?

[chrome bay]

Use client authority

And anti-cheat on the server

[twin juniper]

is there any tutorial for client authority

[chrome bay]

Tell the server what the physics state of the object is, set the server to that then replicate it

No

Well, not that I know of

[thin stratus]

@twin juniper

1. Send Location and Rotation from Client to Server via ServerRPC.
2. In the ServerRPC, send a Multicast to everyone from the Server with the Location and Rotation.
3. In the Multicast, make sure you filter the owning client "IsLocallyControlled == false" and apply the Rotation and Location.

That would be the most straight forward way to do it

Not the nicest but heeeyyyy

That has 0 smoothin though

[sleek current]

@thin stratus What should I do to replicate the USoundBase? I did Replicated in UPROPERTY but it only works on server ><

[thin stratus]

So if it gets laggy, the server/other clients well have a dia show

@sleek current You need to Multicast when you fire

And in the multicast play the sound

[twin juniper]

In the Multicast, make sure you filter the owning client "IsLocallyControlled == false" and apply the Rotation and Location.

[thin stratus]

Or, if you follow along something like ShooterGame, you could increment a RepNotify Integer

[twin juniper]

oh okay i get it

[thin stratus]

And if that integer is > 0, play sound

And if it's == 0, stop playing sound

@twin juniper Yeah otherwise you tell the original client an old position -> snap back

[chrome bay]

One day I'll make a video on this

I must explain it at least three times a week 😄

[twin juniper]

this right

[sleek current]

@thin stratus so basically I need to create another method that is multicast and it only plays sound right?

[twin juniper]

u said server rpc

[thin stratus]

Yeah VFX SFX etc.

@twin juniper

OnTick, call "Re(Server)" IF "IsLocal" is true.

Re(Call) can be removed

[twin juniper]

alright

did that

is this right tho

[thin stratus]

Technically, if I'm not too tired, yeah

[sleek current]

Oh my god thanks multi bible man ❤

If I want to create an interaction interface with interaction component do I need to setup replication on this as well or it will handle itself if its parent is replicated?

[thin stratus]

Interfaces have no sense of replication I would guess

So if you interact with something via an "Interact" function from an interface, then this should already be called on the Server and Client, so replication should happen before calling the interface

[winged badger]

its worth noting that if you try replicating a TScriptInterface

it will just silently fail, won't even toss a warning

[sleek current]

Thanks

[shy nymph]

hey everyone, how do i get the replicated username on the dedicated server side?

[winged badger]

you RPC it over

[shy nymph]

i have my own palyer state with an blueprint exposed function where i use the unreal internal "SetPlayerName"

on the client it shows correctly but the server always prints the original name

[winged badger]

as i said, you need to send it via the RPC

[zealous saffron]

I assume you are calling it on the client

[shy nymph]

but whats the point of the replicated player state and username

[winged badger]

replication flows only server to client

once the server has it, other clients will get it

[zealous saffron]

UE4 doesnt do p2p networking

[winged badger]

but only way for client to push data to server is a RPC

[zealous saffron]

^

[shy nymph]

ohhh that makes sense, of course like any other replication u4 tutorial ever xD damn

sry couldn connect the dots with c++

[winged badger]

UFUNCTION(Server, Reliable, WithValidation) void ServerSetPlayerName(const FString& InName);

bool APS_ValetPlayerState::ServerSerPlayerName_Validate(const FString& InName)
{
    return true;
}
void APS_ValetPlayerState::ServerSetPlayerName_Implementation(const FString& InName)
{
    SetUserPlayerName(InName);
}

should do it

[shy nymph]

can i make this one "BlueprintCallable" as well?

[zealous saffron]

Yes

[winged badger]

then you just call ServerSetPlayerName from SetUserPlayerName if the Role is not authority

or better yet, if (Cast<APlayerController>(GetOwner())->IsLocalPlayerController())

[shy nymph]

Why "_Implementation" and "_validation"

since Visual assist creates them automatically as well but when building since they are not in the header visual studio says they are not declared

[winged badger]

_Validate, not _validation

[shy nymph]

yes _validate sry

[winged badger]

if that one returns false, client that sent the RPC gets kicked

also a good place to implement some anti-cheating checks

[shy nymph]

but i cant build it since "ServerSetPlayerName_Implementation" and "ServerSetPlayerName_Validate" are not declare functions

only "ServerSetPlayerName"

i assume its correct and neccesary but its not building

oh nbm

nvm

[winged badger]

ignore intellisense

[shy nymph]

yea i figured xD

i hate that xD

[fluid flower]

I think I read in 4.23 you won't need the Validate by default anymore

[shy nymph]

@winged badger could you explain a bit more what you meant by good place to implement anti cheating or provide any ressource i would like to know more about that

[winged badger]

a real-life example, a battle royale type game, FPS

they wanted the gunplay to feel responsive

so they gave the authority over hits to the client

[sleek current]

Also guys what is the right way to handle player input in player controller in multiplayer?

Like what RPC, properties to use etc

[winged badger]

few days after release, a hack appeared that was teleporting other players when the cheater fires, forehead in front of the muzzle

validate function eas then made to check if server believes that hit was possible

and if it doesn't kick + ban

[shy nymph]

oh that makes sense, so since the server has authority the players would only be teleported on the cheating client right? and the server checks the position on the hit player on the cheating client and their actual position

@sleek current i think the playermovementcomponent handles all of that

thanks btw works like a charm now

[winged badger]

very much depends on the game

i prefer to avoid clutter whenever possible

so if i have a large amount of related replicated inputs, they'll typically end up in an ActorComponent on the PC

for example

[high current]

Is there a way to do global game text chat, whitout having a dedicated server or a database

also, how is the gameDNA firebase plugin, as I have that from a mega jam, but never used it

[winged badger]

steam lobbies can do it to an extent

our first game made a steam lobby for every 500 users i think, wasn't really a global chat, but it was busy enough

[high current]

haha, using beacons or?

[winged badger]

no

just steam lobbies

[high current]

And is there anything fancy I need to consider for chat

or just rpcing strings

[winged badger]

its not using unreal network

steam lobby

it can send text messages and it can set per user data (also limited to strings)

that's it

[high current]

I have yet to familiarize myself with the steam docs

[winged badger]

with something like UWorks at hand you can put that together in one afternoon

in BP

[high current]

Yeah, it is a uni project so we have to manually implement everything

https://ue4-steamworks-api.readthedocs.io/en/latest/SteamMatchmaking.html

so this derives from the matchmaking part of steam or?

[winged badger]

if you have access to it tho, just quick prototype with uworks will cut your digging thru Steam API to 20% the pain

i think so

[high current]

oh wait that is a plugin and not an official thing

[winged badger]

it was ages since i touched that stuff

yeah, but its not free

[high current]

no longer using steam?

[winged badger]

no, Kaos volunteered last time 😄

[high current]

😄

damn uworks is 132 euros

[winged badger]

advanced sessions might have something

but i don't think they do

all in all its not overly complicated

when user connects (hits multiplayer)

if no lobby with less then N members can be found

his game creates one

and people coming after just find it and join it

few callbacks for chat messages received and functions to send them

also, SetLobbyMemberData and callbacks to others changing theirs (like username)

and you get a free, quick and dirty "global" chat that works

[high current]

Yeah, sounds fun, altho since I have that firebase database thing, might try making use of that

IDK, we are still in the concepting phase, so for now it is mainly doing research prototypes, suggesting methodologies to use during production

[full saddle]

Question, widgets. I have a player tag and the color of the name displayed is binded to player's state "color name" variable. When i change the value of color name it only gets updated on local client. Why is this? Is it that the changes made to player state values dont replicate to server?

[high current]

is the color name variable replicated

and where are you changing that variable on the client

[meager spade]

you have to tell the server the new value

to replicate out

client changing value wont change it on the server, and only server can replicate properties

[full saddle]

Seems like when i change it straight up from the Char BP it replicates properly and when i do it from some other widget it only happens locally.

I knew i had it set up correctly, the logic seemed right for it not to work. This is some weird behavior coming from widgets tho.

[high current]

Replication only works if the proper chain of ownership is followed

http://cedric-neukirchen.net/2017/02/14/multiplayer-network-compendium/

[sleek current]

Hey, I am setting my light switch by interaction and I want it to work both on client and server at the same time as well for late join players

How do I set the RPC's?

Right now I tried Server and netmulticast, Reliable for the method that sets light on/off but server worked only on server as suspected >< and net multicast doesnt replicate to other machines.

[zealous saffron]

multicasts have to be called on a server to run on the server and all clients. You should use an OnRep() function for turning on and off the light rather than a multicast.

[meager spade]

@sleek current check the Blueprint Example in the learn tab of UE4 Launcher, it has a map showing about replication and OnRep vs RPC

RPC's are for one time events, which doesnt matter if a later joiner comes in, etc.

Replicated properties using OnRep is for things like "State, etc"

[sleek current]

What's the name of the example?

[zealous saffron]

OnRep is used for locally dependent values changing based off of a replication event.

[meager spade]

so a IsLightOn bool would would be a replicated bool with RepNotify (ReplicatedUsing in c++), which basically ensures every client see the light on/off

[sleek current]

And how should I actually write it in code?

[meager spade]

c++?

[sleek current]

yes

[meager spade]

UFUNCTION() void OnRep_bLightSwitchedOn();
UFUNCTION(Server, Reliable, WithValidation) void ServerSwitchLight(bool bSwitchOn);```

something like that

client would call ServerSwitchLight

with either on or off

Server would set bLightSwitchedOn which would call OnRep_bLightSwitchedOn on all clients

then clients can set the light according to bLightSwitchedOn

if its a listen server, then server would need to call OnRep_bLightSwitchedOn itself or some function so the host also gets the light state set

[zealous saffron]

OnRep() will not run on the server fyi, so a good practice is to have a server RPC function that changes the value ServerSetLightSwitchedOn(const bool NewValue)

[meager spade]

no point sending const bool

[zealous saffron]

which contains what needs to be run on the server (turning the light off) and the OnRep() call.

really only used for listen based servers, if it's a dedicated server you wouldn't need this setup.

[sleek current]

Sorry but for me it's too late to think. What do I change here?

Too much information ><

[meager spade]

urgh whats with the const bool

bad programming practice 😄

[sleek current]

What's wrong with that?

[meager spade]

http://www.interkaos.com/grabs/Discord_J90koPZxfV.png

it doesnt need to be const

primitives in functions doesnt matter, if the function changes the variable its on the function. but its not needed

const on references sure, like const FVector& SomeVector

as changing that could lead to undesirable behaviour

[zealous saffron]

wouldn't say it's bad programming practice

[meager spade]

its pointless and un-needed

but 🤷 😄

[sleek current]

What ever imo it depends on the application

but what to do to make this lamp work on each machine XD?

[meager spade]

i already explained it

have a server function set a bool, which is replicated

[sleek current]

Sorry but it's too late for me to think for myself 🙂

[meager spade]

quickly types out a prototype, give me a sec

[zealous saffron]

ensures the value won't be changed, fairly sure it's also per epic's coding standard.

Yeah, it is.

[meager spade]

its not

you wont see them use const bool for primitives

in function calls

same as const int32, etc

check all there functions

[zealous saffron]

https://docs.unrealengine.com/en-US/Programming/Development/CodingStandard/index.html

[meager spade]

i am familiar with them, been using UE4 for 3 years now

also have 20+ years programming experience

[zealous saffron]

it says exactly that.

[meager spade]

point me to the exact bit

[zealous saffron]

Example:

void AddSomeThings(const int32 Count);

void AddSomeThings(const int32 Count)
{
    const int32 CountPlusOne = Count + 1;
    // Neither Count nor CountPlusOne can be changed during the body of the function
}

One exception to this is pass-by-value parameters, which will ultimately be moved into a container (see "Move semantics"), but this should be rare.

[meager spade]

i never see that in the engine code

[sleek current]

So I do have the server function to set the light based on bool

[zealous saffron]

I see it a fair amount

[sleek current]

And clients have no connection or what ever to use it 🙂

[meager spade]

and seems pointless, but like i said, i am not arguing over it just stating that is it pointless.

it will only affect that function call anyway, if the function changes it, its on the function

it won't affect anything else

pointers/references, etc then sure, i use const to ensure they are not modified by the function

[zealous saffron]

would disagree again, but to each his own, I can understand why you might see it as pointless. I'd use it to ensure that it wouldn't be changed by accident, also easier to read and grasp the point of the parameter.

Definitely would use it in the above case

that you said

[meager spade]

thing is they put it in the coding standards

to use const on pass by values

two functions here don't use them, and they dont get modified in the function

so 🤷

[sleek current]

ahh

bible guys

[meager spade]

@sleek current give me two secs

[sleek current]

halp

❤

[meager spade]

so do you have a interaction component?

or something to interact with the actors in the level?

[sleek current]

yes

interaction interface and component are created

both work

[meager spade]

and this is on the player or has a route to the player controller

so when you interact with lamp

it tells the server you have interacted, and runs a function on the lamp right?

[sleek current]

pc calls pawn, pawn calls component when interact

basically yes but only on server machine 😛

[meager spade]

so its a Server RPC from the client

[sleek current]

component and interface have no replciation/rpc

[grizzled stirrup]

Has anyone experienced lagging out of PIE / standalone PIE games as a client when run dedicated server is checked?

It's really strange, it's as if you lost connection but any character movement components continue to extrapolate. It just lags out infinitely at a random point when playing

Actually just saw this in the logs: LogNetPlayerMovement: Warning: CreateSavedMove: Hit limit of 96 saved moves (timing out or very bad ping?)

But I don't recall changing anything to do with the CMC lately

[old hamlet]

i just need help with child actors

i have made a gun template that has multiple parameters that allows me to create a child actor that then could have different setting and have multiple weapons just by creating these child actors then setting them up
My issue is that i have 2 weapons and they are both child actors from the same parent , and so it gets confused and it messes up the functionality of both guns or shoots both together

[gusty lily]

having listen server issues with client disconnects. Just reposting my question here in case someone misses it: https://answers.unrealengine.com/questions/926788/view.html

@grizzled stirrup do stat net and check for saturated connections. proabbly over the limit, when this happens to me client connections get very buggy including not being able to move (can't send move info to server i guess), and not having items load in a level. You might need to raise certain bandwidth limits but as per my above post, i'm not sure.

you may have made changs to your game that blew out bandwidth

[worthy perch]

What would you guys say is the (reasonable) maximum for number of projectiles and characters in a networked game at a time?

[grand kestrel]

@worthy perch Depends heavily on whether you're pooling the projectiles or not

Also on your tick rate

Fortnite gets 100 players at shit tier 30hz tick rate who fire projectiles, but IIRC epic has high frequency low core servers

What you actually accomplish depends on you and the server

Expect to hit your limit at around 40 with ~60-80hz running on google cloud, with decent optimization

Gotta know what you're doing

Then again, Bluehole never knew what they were doing and still made PUBG with higher player count, so maybe I'm wrong

But it's all client-side

So they get lots of hackers

[worthy perch]

Thanks, Vaei.
And no, I am not pooling anything. I was vaguely told that it was too difficult and never really pursued it.
I am also relying on listen servers, which makes things weird in terms of performance boundaries.

[grand kestrel]

@worthy perch If you're using projectiles for everything you'll need to, because automatic weapons will tank the performance

Pooling isn't easy or fun, I've done it both for a physically simulated foliage system and projectiles so far, it's a fair bit of work ironing out the issues, UE4 really isn't built for it

Multiplayer makes it a lot harder, but its doable

The better compromise is to use hitscan for automatic weapons and projectiles for snipers, rockets, and so forth

Even with hitscan you can fake travel time

And bullet drop

[worthy perch]

The better compromise is to use hitscan for automatic weapons and projectiles for snipers, rockets, and so forth
Yeah, I had settled with this. And melee weapons.

[mighty rover]

So I think I've hit a wall in my understanding of replication. I have working gameplay for my game in a dedicated server environment. The pawn has an RPC event that runs once they log into the server, to spawn a new object attached to this pawn. Each player can see the movement of each other's objects accurately; however, this object has a texture parameter that is supposed to change the texture (via dynamic material) displayed on it. This texture is not being set onto the replicated pawn object. I can see from the dedicated server, via server print string that both pawns custom texture information is correct, it just won't change on the object. Any pointers? Thanks in advance. Here's a screenshot of game of both screens (don't mind FPS, right screen has focus lol). And signed in as the same login, so both names are the same, but repliation on UI is working as well.

[slender yarrow]

textures and materials usually have to be updated with rep notify or multicast from what ive learned

[mighty rover]

Both material and texture are replicated within rep notify's of the object blueprint. Then I set each variable after login from the pawn via reference, after the object is spawned within the pawn blueprint.

To eliminate material mismatch issues though, I set the default material as the material instance, and don't really do anything with it. Just update the texture parameter within the texture repnotify function

[slender yarrow]

also. If a rep notify variable doesnt change the function doesnt get called I believe. Maybe make sure 100% the repy notify value is changing when this event is fired

[mighty rover]

Thanks. I'll keep at it and try to get some more functional testing done

[winged badger]

@mighty rover unless that new object requires specific information from the client, its more elegant to just spawn it in HandleStartingNewPlayer in GM

did you create the Dynamic Material Instance both client and server side?

[mighty rover]

@winged badger - I'm only creating it within the repnotify of the object blueprint

the process of how it gets to that point is: Player logins into DS -> Pawn spawns -> RPC Event called within Pawn that spawns BP_Hitter -> Set BP_HitterRef -> BP_HitterRef -> Set Texture node.

[winged badger]

you create DIM

you don't assign it as material to the Mesh

there

you also need to create it only once

[main spindle]

I also want help but I don't want to interrupt 😄

[winged badger]

BeginPlay works, or GetMaterialInstance function that returns the MaterialInstance variable if its valid, if not creates one, assigns it to materials, and return it

[mighty rover]

@main spindle nah join in the fun lol

[winged badger]

if you put the texture ref as expose on spawn

then texture will be set before BeginPlay, both on server and client

assuming you provide a valid one server side when you spawn it

[mighty rover]

Ok, let me give that a try. Yeah, a valid one is present prior to spawning BP_Hitter

[winged badger]

you still need to SetMaterial

in any case

also needs to be done just once, if DIM is not recreated all the time

[mighty rover]

Converted it to this:

[thin stratus]

The CreateDynamicMaterialInstance function of a StaticMesh creates and sets the variable.

If you get the Material and cast it to DynMatInst then you can check if that's already set.

But your solution also works of course

[flint belfry]

Hey guys, Im working on a Multiplayer VR game for oculus quest, I have both quests connecting to a server hosted on my pc but the motion controllers arent replicating, have tried using different kinds of events, any help would be appriciated?

[thin stratus]

What are you doing to replicate them?

Cause they aren't by default iirc.

[flint belfry]

atm i have two spheres that im setting the world location the same as the motion controllers using a has authority node if it has authority i am using a multicast event and if its a remote im running it on server

[mighty rover]

@winged badger - almost fully working. Except the same texture is being applied to both player's objects, even though they should be different. But I'm in a much better position to solve this issue now than I was before, so thank you 👌 at least the texture is changing now. Stoked!

[summer nova]

pooling being hard... what?

pooling is generally considerably trivial for stuff like projectiles

also, both fortnite and pubg are much, much worse optimized than they could be

AND they run 3 matches on 1 core of their servers

(overlapped, so when one match is ending, another one is starting)

if you know what you are doing

completely ignore the character movement

and use proper patterns and replication graph

im confident you can do MMO scale

300 players in 1 server should be doable if its planned from minute 1

if we were to fully rebuild PUBG from scratch, focused on scalability, we could do a battle royale with 300 players in one map at better perf than current PUBG

[high current]

@winged badger you suggested the global chat with the steam lobbies thing right

but that doesn't account for the fact that the host of the lobby might disconnect, so you have to select a new host and so on

[winged badger]

nope, steam will do that under the hood

[high current]

or perhaps I am not familiar with steam lobbies enough yet

[winged badger]

and you don't provide an interface for that player to be able to kick lobby members and such, or inform them they are lobby leader

[high current]

yeah, but dont these things require level loading

or does steam lobbies work outside levels

[winged badger]

its not a connection using unreal at all

[high current]

like beacons do

aah

ok

[thin stratus]

Beacons are also not required to use Steam

You have to draw a big line between Session/Lobby and whatever UE4 does.

You can for example create a Session and not open a new Level with ?listen.
That totally works, but connecting then (which then is UE4 again) will of course fail.

[high current]

Ok so then what are the benefits of opening a session and not a level afterwards, if UE4 will fail

[thin stratus]

There is none, just making sure you are aware that it would work.

They are not tied to each other.

Sessions only hold information.

@high current

---

Is there a general "flow" of error messages when having disconnects etc.?
I know we have HandleTravelError and HandleConnectionError or so in the GameInstance.
I also know that there is a function to remove a client with a given message (e.g. at the end of the match to send them home or to kick them).
I'm trying to figure out a way to pipe all of that throug hthe same code to show some dialog in the mainMenu

Currently thinking a GI Subsystem for handling these messages might be good. Then I can listen to the Travel and Connection stuff and also give it a public function to pass in a custom message.

Could hold them in a queue in case multiple ones happen

Also how valid is it to listen to the PostLoadMapWithWorld and checking if the current level is e.g. Level_MainMenu?

Because I only need to trigger emptying the queue of errors when the player is in the mainMenu

[fleet raven]

I just stored all these errors on the game instance (set LastXXError properties and otherwise ignore the callback) then in the main menu hud I check if they're set and decide to show a dialog or not

[thin stratus]

Right, so that's pretty much what I planned for.

Not sure what LastXXError means though

[fleet raven]

well there are multiple

LastTravelError, LastNetworkError, etc

[thin stratus]

I would just always check if the queue is empty and if not start showing it one by one.

[fleet raven]

I suppose you could also just have a queue of general errors

[thin stratus]

Ah so you hold multiple queues for each type?

[fleet raven]

there's never more than one of these so it's not necessary to have a queue, just whether an error occured or not

[thin stratus]

Iirc the ConnectionLost error already comes with two different ones

My LobbyKit always returns two things, ConnectionLost and some generic "Error" shizzle

[fleet raven]

hm

I don't use any online subsystem stuff so maybe they add more

[thin stratus]

Right, so you just have one signle LastNetworkError and LastTravelError

And you check if they are set or not

And they display them

[fleet raven]

yeah

[thin stratus]

Are you using the same system for things like "You were kicked!"?

(or would you if you would have a kick feature)

[fleet raven]

I haven't actually set that up yet, it just shows "connection lost"

wanted to do that eventually

[thin stratus]

Oh, how are you kicking them? :D

[fleet raven]

just destroying the player controller

[thin stratus]

Right that would probably end up being connection lost

[fleet raven]

there doesn't seem to be a real builtin "kick with message" function

[thin stratus]

There is but it does the same

bool AGameSession::KickPlayer(APlayerController* KickedPlayer, const FText& KickReason)
{
    // Do not kick logged admins
    if (KickedPlayer != NULL && Cast<UNetConnection>(KickedPlayer->Player) != NULL)
    {
        if (KickedPlayer->GetPawn() != NULL)
        {
            KickedPlayer->GetPawn()->Destroy();
        }

        KickedPlayer->ClientWasKicked(KickReason);

        if (KickedPlayer != NULL)
        {
            KickedPlayer->Destroy();
        }

        return true;
    }
    return false;
}

[fleet raven]

yeah I found that but I am confused how it works

[thin stratus]

void APlayerController::ClientWasKicked_Implementation(const FText& KickReason)
{
}

Probably the same way

[fleet raven]

if destroy is supposed to terminate the connection how would the rpc ever be received

[thin stratus]

They send a last RPC

And then kill the controller

I guess the Destroy of a PlayerController checks pending RPCs?

As we all know that Destroy isn't directly deleting

[fleet raven]

destroying the player controller by itself doesn't actually do jack

somewhere the connection checks whether it still exists

[thin stratus]

UWorld destroys

And that checks DestroyNetworkActorHandled

bool APlayerController::DestroyNetworkActorHandled()
{
    UNetConnection* C = Cast<UNetConnection>(Player);
    if (C)
    {
        if (C->Channels[0] && C->State != USOCK_Closed)
        {
            C->bPendingDestroy = true;
            C->Channels[0]->Close(EChannelCloseReason::Destroyed);
        }
        return true;
    }

    return false;
}

Which does this

[fleet raven]

oh

[thin stratus]

Now I don't know enough about connections

To know if that would allow the rpc to still happen

[fleet raven]

this is highly sketchy

[thin stratus]

It does stop the actor from actively being destroyed

Cause that early exists the destroy function of the world

I noticed that last time I treid to destroy a fake playerController that we used in Party Beacons to have voice

[high current]

Ill try to do the steam chat thing with the Advanced Sessions plugin, if not I guess I have to expose a bunch of stuff from c++, right?

[thin stratus]

        if (ThisActor->DestroyNetworkActorHandled())
        {
            // Network actor short circuited the destroy (network will cleanup properly)
            // Don't destroy PlayerControllers and BeaconClients
            return false;
        }

[fleet raven]

I love how backwards the function name is

[thin stratus]

Yeah :D

Either way, it's a bit weird that they would just destroy the PC to remove them

I would have guessed they send them back to the original level

similar to connection lost

Cause why would a kick want to trigger ConnectionLost

So one would need to save that the player was kicked, to make sure they don't show ConnectionLost

[fleet raven]

because it needs to actively cut the connection so players can't keep lingering around

if you told them to travel they could just not

[thin stratus]

Yeah sure, but send them home before that? The ClientRPC could just open the last level

If you leave a game you also just call OpenLevel MainMenu

I never actively destroyed the PC

But maybe I'm wrong there

[fleet raven]

yeah I am also doing open level mainmenu when the client disconnects itself

I'm just concerned that this rpc might not be guaranteed to arrive

say if the packet is dropped

does it wait with destroying the connection until it has been resent on the actor channel?

[thin stratus]

I honestly don't know

I do see that the UConnection checks if it's PendingDestroy

And doesn't trigger the ConnectionTimeout then

So technically that shouldn't show up (ConnectionLost)

Ah actually ConnectionTimeout != ConnectionLost, nvm me

bool AUTGameSessionNonRanked::KickPlayer(APlayerController* KickedPlayer, const FText& KickReason)
{
    // Do not kick logged admins
    if (KickedPlayer != NULL && Cast<UNetConnection>(KickedPlayer->Player) != NULL)
    {
        APlayerState* PS = KickedPlayer->PlayerState;
        if (PS)
        {
            if (UTBaseGameMode && UTBaseGameMode->IsGameInstanceServer())
            {
                UUTGameEngine* UTGameEngine = Cast<UUTGameEngine>(GEngine);
                if (UTGameEngine)
                {
                    UTGameEngine->InstanceBannedUsers.Add(FBanInfo(PS->PlayerName, PS->UniqueId.ToString()));
                }
            }
        }
        AUTBasePlayerController* KickedBasePlayer = Cast<AUTBasePlayerController>(KickedPlayer);
        if (KickedBasePlayer != nullptr)
        {
            KickedBasePlayer->GuaranteedKick(KickReason, true);
        }
        return true;
    }
    else
    {
        return false;
    }
}

That's what UT does

Let's check GuaranteedKick, shall we

[fleet raven]

ye

[thin stratus]

Aha

void AUTBasePlayerController::GuaranteedKick( const FText& KickReason, bool bKickToHubIfPossible)
{
    if (!AuthKickHandle.IsValid())
    {

        if (bKickToHubIfPossible)
        {
            ClientReturnToLobby(true,false);
        }
        else
        {
            ClientWasKicked(KickReason);
        }

        GetWorldTimerManager().SetTimer(AuthKickHandle, this, &AUTBasePlayerController::TimedKick, 1.0f, false);
    }
}

void AUTBasePlayerController::TimedKick()
{
    Destroy();
}

They delay it by a second

Sneaky

[fleet raven]

what does client return to lobby do?

[thin stratus]

One sec

First, here is the kick one

void AUTBasePlayerController::ClientWasKicked_Implementation(const FText& KickReason)
{
    ULocalPlayer* UTLocalPlayer = Cast<ULocalPlayer>(Player);
    if (UTLocalPlayer != nullptr)
    {
        UUTGameViewportClient* ViewportClient = Cast<UUTGameViewportClient>(UTLocalPlayer->ViewportClient);
        if (ViewportClient != nullptr)
        {
            ViewportClient->KickReason = KickReason;
        }
    }

    UPartyContext* PartyContext = Cast<UPartyContext>(UBlueprintContextLibrary::GetContext(GetWorld(), UPartyContext::StaticClass()));
    if (PartyContext)
    {
        if (PartyContext->GetPartySize() > 1)
        {
            PartyContext->LeaveParty();
        }
    }
}

void AUTBasePlayerController::ClientReturnToLobby_Implementation(bool bKicked, bool bIdle)
{
    UUTLocalPlayer* LP = Cast<UUTLocalPlayer>(Player);
    if (LP)
    {
        LP->LastRankedMatchSessionId.Empty();
        LP->LastRankedMatchPlayerId.Empty();
        LP->LastRankedMatchTimeString.Empty();
        LP->SaveConfig();
    }

    if (bKicked)
    {
        ClientWasKicked(bIdle ? NSLOCTEXT("General", "IdleKick", "You were kicked for being idle.") : NSLOCTEXT("General", "HostKick", "You were kicked by the host or admin.") );
    }

    AUTGameState* GameState = GetWorld()->GetGameState<AUTGameState>();
    if (LP && !LP->ReturnDestinationGuidString.IsEmpty())
    {
        ConnectToServerViaGUID(LP->ReturnDestinationGuidString, false);
    }
    else
    {
        ConsoleCommand("Disconnect");
    }
}

And that's the return one

[fleet raven]

so they just dump it on the viewport client instead of the game instance, but otherwise same thing

[thin stratus]

Right but they call Disconnect

[fleet raven]

but only for return to hub, not the other kick

[thin stratus]

I love the totally unneeded GameState

[fleet raven]

I wonder if the compiler is able to remove that

[thin stratus]

They never use the function without ToHub being true

So you can probably ignore the false case

[fleet raven]

extra

[thin stratus]

We might need it.

So they also use ClientReturnToLobby when checking if a player idles

Which is fair

End from GameMode when calling SendEveryoneBackToLobby

Means they always just disconnect the player or send them to that Destination string

But that DestinationGUID stuff is UT specific

So yeah, disconnecting seems to need the delay for the RPC.
They do use Disconnect instead of OpenLevel(MainMenu).

And the rest seems the same.

[fleet raven]

waiting a second is extremely sketchy

what if the client was lagging?

[thin stratus]

Yeah idk tbh, guess you would see connection lost

Still don't get why the server can't kill the PlayerController after the player securely left

Why does it have to be based on the initial kick call

I mean if I disconnect it also cleans up the playerController

So why even bothering destroying it by hand

[ivory portal]

PostSeamlessTravel <--- Is only called on the server side?

[grizzled stirrup]

@gusty lily Re your reply about me lagging out of a PIE game as a client: the network definitely wasn't saturated at the times I lagged out, and even so I have greatly increased all of the bandwidth caps. I have tested on packaged builds and the issue doesn't seem to occur so it may be a bug with playing standalone as a client with a dedicated server instance, or some other rare bug that I didn't trigger on my more recent tests. It may well be due to some high fps related problem too as I set t.MaxFPS 500 on begin play

[sleek current]

Where do I write my widget show and hide methods in multi so only a player that shouldsee it will see it?

Because in most cases I found ppl use GetFirstPlayerController and that doesnt work for me. I have a press button to interact, and I have no idea which class to use for it to make it right or atleast work.

[grizzled stirrup]

@sleek current Use the HUD class

It's clientside

[sleek current]

Already done

But then I have a interaction component

That tells the pawn whether or not he has anything to interact

And I want to call there the ShowPressButtonWIdget() and hide methods

But goddamn I odnt know how to do it so it will work for multi

In single I would just create a pointer to HUD inside component to first player controller HUD

but here I have no idea how to do it in multi :C

[sleek current]

HUD = Cast<AFarmHUD>(GetOwner()->GetNetOwningPlayer()->PlayerController); it all goes to this line. Anyone knows how to get from a actor component of a pawn class it's pawn(owner) player controller?

[grizzled stirrup]

@sleek current You should never really be using those GetFirstPlayerController / character methods

I usually communicate things through the PlayerController to the HUD

[sleek current]

But how do you do it if it's press button to interact

[grizzled stirrup]

So get a reference to the PC and if it's on the server you can do a client RPC down to make the client show the HUD. If it's clientside then no need for a client RPC and you can call it directly

[sleek current]

So pointer to pc in HUD, but still how do I get the value to actually get it?

[grizzled stirrup]

No pointer to PC in interaction component

PC calls function which gets the HUD and calls the function on it

So PC is basically the messenger from external classes and HUD does all the clientside show / hide etc.

[sleek current]

alright

so

PC pointer in component

But still how do I tell the pointer which memory address he should be?

[grizzled stirrup]

Well it depends on how you have set up your interaction component

I'm assuming you interact from a character?

So the character could provide the PC reference

If your character implements the interaction component then you can get a reference to the owner / owning controller etc.

If your interaction component is on the actual interactables in the world then you can pass the Character / controller reference on interacting if needs be

I poll for the best nearby interactable actor two times a second in my character, if there is one, BestInteractable gets set which is a pointer to my interactable actor type

then if the player hits the interact key I run this

if (BestInteractable)
{
    BestInteractable->OnInteractedWith(this);
}

So now the interactable has a reference to the character that interacted with it and can do whatever it needs to: check if it can be interacted with by this character, show UI, whatever

I do this via a server RPC so it happens on the server but the logic is generally the same

[sleek current]

Thank you, will try something like that

[high current]

To make sure that I am on the right path, the text chat should be implemented somehow from
IOnlineChatPtrand GetChatInterface()

right?

Or did you guys mean it involves the usage of some things from the steam api that arent in the steam subsystem

[sleek current]

Hey, I have a widget component inside an actor. I want it to rotate to face each player, I know how to do the rotating part but how do I make it for each client and for the server?

[high current]

by not replicating it

¯_(ツ)_/¯

Shaders are great for that, as you can make it face the camera inside the shader and you are pretty much done, but I don't know about widget materials

Otherwise, your rotation code just has to take the camera of the local player controller

so in this case getplayercontroller{0} might be actually useful

[winged badger]

you can just rotate it on Tick

with no replication involved

towards the camera of the local PC

he's doing c++, so UGameInstance::GetFirstLocalPlayerController() is what i'd go for

[sleek current]

Aight how to make sound of shooting projectiles and playsoundatlocation methods on multiplayer?

[winged badger]

you run a simulation that does it

not always possible, depends on a game, but recommended

[high current]

btw, Zlo can you shine a light on my question above, I wanna know if I am wasting my time figuring out how to expose the chatinterface to BP via c++

[winged badger]

if you fire 50 bullets in a second from your minigun

you don't really care if one client sees 30 hits and other 26

as long as you can do a close enough that is imperceptible by the player, and that simplifies your network, go for it

[sleek current]

Okay

How do I replicated destructible mesh?

[winged badger]

never saw that interface before

you replicate the condition that made it go boom

and you make it go boom on each client individually

i wouldn't try anything more accurate unless i really had to

[high current]

so the individual chunks wont match on clients (unless the destructible mesh supports replicated movement)

[winged badger]

thats what particle systems are for

smoke and mirrors

[high current]

https://www.unrealengine.com/marketplace/en-US/slug/dent-destructible-environment

[winged badger]

replicate any damage worthy of note... tada

there is apparently a full chat system in GameMode/PCs of all things

[high current]

waat

[winged badger]

@pallid mesa i summon you

[high current]

I mean, if I could just have access to like a shared player state or something, I can make my own chat

[sleek current]

I just made the method server and reliable

[high current]

cries in replication

[sleek current]

and now it doesnt destroy it on anything but server

[high current]

Well you need to play that on clients as well

[winged badger]

server and reliable is client telling the server "hey i did this, its important"

nothing more

[sleek current]

Aight then how can I call it on everything>?

[winged badger]

vorixo did a chat system using GM/PC stuff built in the engine

he's usually lurking around

[high current]

Yeah, he posted yesterday on twitter, so I know he is here somewhere 😄

[pallid mesa]

hello

[high current]

I can just leave the chat thing to the programmers, but I am just curious and wanna start learning MP in c++

[pallid mesa]

so... ULocalMessages tapa

[high current]

vo, where did the r go

I have a jira task

🙂

[pallid mesa]

you know about them

[high current]

to implement those

[pallid mesa]

gave you a C++ component that you can invoke in BP's

feel free to use it and report what's missing

[high current]

Did you do chat with them

[pallid mesa]

who?

[high current]

well with it (ULocalMessage)

[pallid mesa]

yep chat and other sorts of systems

basically all UI msgs are based on that

• chat system

[high current]

but it is all once all clients are connected

[pallid mesa]

if you can centralise all messaging in a system that it already exists in the engine, good.

[high current]

in the same map

[pallid mesa]

yes. Ofc, that consumes game server bandwidth

it's a in-game chat

but you can forward it to any other subsystem

such as a external chat server

[high current]

Yeah, no for ingame imma use the Ulocalmsg, as it it perfect for that. But my question was regarding just having global chat

and the thing is that we want to avoid using anything else

[winged badger]

i did not scroll up that far 😄

[high current]

lol, its fine

[pallid mesa]

you can still use ULocalMsg, however you'll need to override the send and receive implementations

ulocalmsg is a wrapper

[high current]

but yeah, someone suggested using what steam already has as chat

[pallid mesa]

you can mix steam and ulocalmessage

no issue there

actually /w @\username forwards to steam and prints on UI throught LocalUIMsg

in my case

[high current]

Someone also mentioned steam lobbies, is that different than sessions

and I couldnt find it in the steam subsystem

[winged badger]

i did

[high current]

so I guess it is in the steam api

[winged badger]

Kaos did an implementation recently, and is typing, it seems

[high current]

cause I liked the lobbies idea, with silently connecting people based on region for examle

[pallid mesa]

lobbies and beacons might be great to have a subset of players communicating between themselves

[winged badger]

you could even run your ingame chat via steam lobbies

and not use your listen server's bandwidth

[pallid mesa]

^

but still use ULocalMessage

[high current]

yeah, but does a chat really use that much bandwidth

[pallid mesa]

it's totally compatible

[high current]

well I guess yeah, if someone spams it

but still

[pallid mesa]

not really... a chat shouldn't take much

you cap the char limit and you put int a coldown for spammers

[sleek current]

Ayy I made it work on client's and on server

[pallid mesa]

you will need those systems anyways

[sleek current]

now only last question

how to make it work on late join?

[winged badger]

replicated variable instead of a multicast

[pallid mesa]

late joiners are my vibe, Zlo knows it

XD

[sleek current]

I dont have any multicast

[high current]

oof, I still have to fix some late join issues in the UT mod

[winged badger]

lol, broke the engine a little there

[pallid mesa]

had to do PR for 4.23 due to a net culling issue with posessions and late joiners XD

[sleek current]

UPROPERTY(EditDefaultsOnly, ReplicatedUsing = OnRep_Destroy, BlueprintReadOnly, Category = Destructible)
bool IsDestroyed;

void ADestructibleProp::OnRep_Destroy()
{
if (!IsDestroyed)
{
IsDestroyed = true;

    Destructible->AddRadialImpulse(GetActorLocation(), 1000.f, 1000.f, ERadialImpulseFalloff::RIF_Constant, false);
    Destructible->AddRadialForce(GetActorLocation(), 1000.f, 1000.f, ERadialImpulseFalloff::RIF_Constant, false);

    if (Particle)
    {
        UGameplayStatics::SpawnEmitterAtLocation(GetWorld(), Particle, FVector(GetActorLocation().X, GetActorLocation().Y, GetActorLocation().Z + 15), FRotator(0.f, 0.f, 0.f));
    }
    
    if (Sound)
    {
        UGameplayStatics::PlaySoundAtLocation(GetWorld(), Sound, GetActorLocation(), 1.f, 1.f, 0.f);
    }
}

}

UFUNCTION()
void OnRep_Destroy();

[winged badger]

EditDefaultsOnly makes no sense there

[high current]

^

[winged badger]

EditInstanceOnly does tho

[pallid mesa]

well... your onrep doesn't make much sense

[winged badger]

that is also true

this will cause stuff like

you blow up a bunch of barrels and whatnot

and 10 minutes later i walk into net relevancy range and i see them explode

exact same issue as dead monsters getting up to play their death montage

[high current]

spicy

[sleek current]

so what should I do?

[winged badger]

sync your time with the server, using replicated var in GS if you don't care for more accurate solution

replicate the float Timestamp

which is server's GameTimeSeconds() at the time it blew up

[sleek current]

you talk about things that I have no idea about, whats GS,timestamp, how to get to it

[winged badger]

it can be set by default to something invalid, like -1 for objects that didn't go bang

[pallid mesa]

another thing you can do that is more expensive is to MCast the effects and onrep the functionality.......... <- that is if you don't care about performance in your case

[high current]

Game State

AGameState in your case

timestamps refer to timestaps per specific receieved update

[winged badger]

so, object explodes 2133 seconds into a match

[high current]

I saved this from the other day

[pallid mesa]

timestamp is pretty critical in MP games, yes.

[winged badger]

server replicates the float 2133 (its gametimeseconds)

[pallid mesa]

Great advice

[winged badger]

client recalculates what the server time 2133 is in its own gametimeseconds

[sleek current]

SO I should create a GS class and play with its time stamp?

[winged badger]

and if its happening NOW, it runs the kaboom code

it it happened 3 minutes ago, it just shows you the charred remains

GS already replicates the server's timestamp by default

what MrTapa c/ped there is how to make a more accurate system

[pallid mesa]

also... one last question, is this what I think it is?

   if (!IsDestroyed)
   {
            IsDestroyed = true;

that's usually used when you don't ensure your destroy function is called once and only once

[meager spade]

explosions should be multicast, the destroyed barrel state should be a OnRep

[winged badger]

thats the code that will make every unexploded object go kaboom

[pallid mesa]

and in this case an explosion for the client is a one time event that you shouldn't check on

[meager spade]

explosions should only happen to the players relevant at the time

[winged badger]

before BeginPlay on clients

as the initial state will replicate, before BeginPlay is called

and it will trigger the OnRep

[sleek current]

Goddamn, I literally have 1.5hours left to complete the task and you guys talk about stuff that I need to sleep with to compile XD

[pallid mesa]

erase that bit of code

and ensure variable initialization

[winged badger]

Kaos provided a most straightforward solution

[pallid mesa]

ensure also that this destructon code doesn't get called twice (hence only once per client)

[winged badger]

you can do that by doing this

[pallid mesa]

tbf kaos copied me >,>

[winged badger]

void OnRep_Destroyed(bool OldState);

when the OnRep is called, the OldState will contain a value before the replication

then you do if (Destroyed != OldState)

and you do not set the variable you're doing the OnRep for inside the OnRep

its set before the OnRep was called

(in BP doing that will create an infinite loop, btw - i hate networking in BP)

[sleek current]

OldState when I call this method is just destroyed variable?

[pallid mesa]

old state is the previous value of your onrep before it replicated

[winged badger]

OldState is destroyed variable before replication

and Destroyed is the destroyed variable after replication

by the time OnRep runs, its already set

to new value received from the server

[sleek current]

Alright then

What rpcs should I use in .h?

[winged badger]

so

your client makes an object explode

[silent birch]

I want in my game that if you shoot a person you have more to score but it adds to the one who was touched while I want it to add to the one who shot

[winged badger]

Server, Reliable sends that information to server

[silent birch]

Who can't help me?

[winged badger]

server, inside the _Implementation

sets the destroyed variable, which will set the objects visual state to charred remains

[sleek current]

SO there should be 2 methods Destroy() one for client and one for server?

[grand kestrel]

Is there a blueprint event for receiving a player state on client? I could add it myself but want BP only users to utilize it for my plugin

[winged badger]

and runs a NetMulticast, Reliable

inside which clients run the explosion visuals and sounds

its not a perfect solution, and can be improved upon

but its the only one you have time for, apparently

[silent birch]

While at the Spawn node actor from class I have put in places instigator get instigator

[grand kestrel]

Seriously wondering why APawn::Restart() isn't exposed to BP

[sleek current]

Zlo but how many methods

[winged badger]

@grand kestrel almost 100% reliable solve is to increase PS NetPriority to around 4

[sleek current]

Client makes objects explode that means there is one to explode, right?

Then server reliable sends it to server

so second one with same body for server

[winged badger]

it can fail miserably if there is packet loss tho

[grand kestrel]

@winged badger I really just want APawn::Restart but exposed by default.. in 4.22, so if there is nothing I'll have to do things differently

Just need an event on client once player state exists -__-

[winged badger]

there are OnReps for PS in PC and on Pawn

[grand kestrel]

Really? I didn't see any BP access specifiers

[winged badger]

oh there are none

[grand kestrel]

Yeah its very easy to solve in C++ or exposing it myself but I want it to be BP friendly

[winged badger]

plugin here is problematic

part

[silent birch]

Who can't help me?

[grand kestrel]

See so many poor BP users using a 1s delay from BeginPlay to circumvent it

Which isn't even 100% reliable

[winged badger]

@sleek current local sim is improvement

you can do when you get the rough version working

client wants to make something explode -> Server, Reliable RPC

server sets Destroyed and -> NetMulticast, Reliable RPC

that netmulticast will run on server, client who initiated it all and on every other client

OnRep_Destroyed sets the visual state of the object

Server RPC _Implementation applies damage and such

[wary willow]

@grand kestrel You are asking about Restart event right?

[winged badger]

and Multicast _Implementation plays particles and visuals

[wary willow]

If so, there is one expose to BP

Or is it Reset, looking now

[high current]

someone say, delays in BP

🙂

[wary willow]

^ best way to do it

[winged badger]

can you implement a custom PS without breaking the plugin @grand kestrel ?

[wary willow]

Sometimes

[silent birch]

So for get instigator

[sleek current]

I did something wrong and it doesnt call the destruction

[grand kestrel]

@high current That's so gross and should be unnecessary, if they exposed APawn::Restart() to BP it's called once there is a valid PlayerState and PlayerController

It's effectively a BeginPlay with both of those present

And runs on server and all clients

[winged badger]

@sleek current destructible object isn't owned by your client's PC

so you need to implement the original Server, Reliable in an object that is

[sleek current]

sorry but

what

destructible isnt owned so implement server, reliable in the one that is owned

PFUFFFHHH here goes my brain XD

[winged badger]

you ever read exi's compendium?

[sleek current]

Yes I did but I dont remember the whole thing since it was an quality heavy punch of informations

[winged badger]

you can only send server RPCs through the PC

or object owned by the PC

[sleek current]

So basically I should call an RPC in PC by some event or smth?

[winged badger]

that would work

then the server version of the PC

tells the destructible to go kaboom

(that would be inside the RPCs _Implementation)

you make sure you send a pointer to destructible as an argument there

[sleek current]

So destructible calls an event on PC with argument (this)

And then pc does what exactly? Besides then calling the server kaboom

[high current]

@grand kestrel ik the image is kind of meme

[winged badger]

PC should have an idea that you're trying to destroy the object already

or your Pawn, or PlayerState, they can all send the RPC

[sleek current]

Alright

[winged badger]

having a random object in a level access your PC and start calling functions on it is kind of a code design you will end up regretting

[sleek current]

How do the destructible can call a specific PC?

How can I get a memory address for each player?

[winged badger]

or laughing at 6 months later "lol, what newb wrote this?"

[sleek current]

I mean I know I dont want that I only want the kaboom to happen on the destructible but you ma bible man

[winged badger]

how does the object go kaboom?

start with "player presses a button"

(the singleplayer version is fine)

[sleek current]

could we pm?

[winged badger]

others might learn from it

[sleek current]

After this multicast and server

it doesnt kaboom

[winged badger]

no

say you're playing solo

listen server

you press a button

how does that button get to kaboom

[sleek current]

Before it only didnt work for late join's

now the variable isdestroyed has wrong state on machines

and the hp goes to the negative value

[winged badger]

so then you're overcomplicating your life

[sleek current]

still not calling the destroy

[winged badger]

if you had it not working for late joiners only

all you need to add to that version

is OnRep_Destroyed with a variable that will make late joiners see the remains of a dead object

nothing else

[sleek current]

Input from PC->calls method in Pawn->Pawn calls a interact component->interact component calls interact method from interface on destructible->destructible kaboom

[meager spade]

Interact should already be called on the server

we made that a server rpc if its a client

last night right?

[sleek current]

we made the lamp

[winged badger]

it was always a server RPC

[sleek current]

the interaction is totally left withouit any rpc

[winged badger]

interactable actor isn't plugged in yet

[sleek current]

and it works

[meager spade]

which mean Interact is an RPC tho

cause we did a check

if its not authority call ServerInteract

else we just call Interact

[winged badger]

yes, that hasn't changed

[meager spade]

ok

making sure

[high current]

Wouldnt spawning a decal as a separate actor work better for that case, as you can actually destory the object and still have late joiners know what happened as the netdriver will spawn the decal actor

[winged badger]

(we do work together if anyone finds this exchange confusing)

@sleek current only thing late joiners need to see is that object is destroyed already

nothing else

so start from a version that was working except for late joiners

and add the code that does just that

change the object OnRep_Destroyed, if Destroyed is true, to look destroyed

nothing else whatsoever

we also helped lead you down the overcomplicated path, sorry for that

[sleek current]

so I am right now at the version that works but only doesnt show the late joiners destroyed object

[meager spade]

@sleek current just in a nutshell, RPCs are for telling the server (or server telling the client/clients) that something has just happend. Replicated properties are for maintaining a state across replicated actors (as long as server is setting the replicated property). RepNotify (OnRep) is used for things that should happen when that property is changed. RPC's are never sent to late joiners, but replicated properties (if they are different) are sent to the late joiner. So taking that in to account, your OnRep should just basically set the mesh/actor to the dead state. Your actual explosion should be an RPC or a property using some kind of time check to stop it being played again for late joiners. But the simplest approach is ReplicatedUsing to handle the state of the actor (exploded or alive) via the OnRep call, and a Multicast for the actual explosion. If a late joiner joins during the explosion, they won't see the explosion but who cares, they see the dead object already exploded tho. its just one of those smoke and mirror things, and you would be suprised how many games do it. its just simpler.

[sleek current]

What I did wrong here?

Still doesnt work for late joiners

[winged badger]

you don't explode it

you just change the mesh to look charred

spawn a crater decal

something

[sleek current]

cant late joiner just see somehow the destroyed mesh?

[winged badger]

late joiners load the object from the package (level)

it replicates its replicated variables

and runs any OnReps

then calls BeginPlay

(same case for walking into net relevant range)

so they see the object as is, after that is done

[sleek current]

What should I do to call the destruction if certain object is destroyed for late joiner?

[silent birch]

GET INSTIGATOR

[winged badger]

you don't destroy it

you just make it look destroyed

no explosion again

just the aftereffects

and you have to do that from OnRep

[sleek current]

So I need to create an OnRep_Method() that does anything besides exploding again to make it look destroyed?

[meager spade]

thats the idea

OnRep should be for "State"

[sleek current]

How can I send variables from actor to its widget component?

[winged badger]

you generally don't

the Widget on the WidgetComponent should have a reference to the Actor

and if it needs to react to something specific when it happens, use a delegate after that

[sleek current]

Basically I have a widget component with progress bar over the destructibles to represent the destructible life

[winged badger]

but you can access the widget

Cast<UMyWidgetType>(WidgetComponent->GetUserWidgetObject) iirc

[silent birch]

Help me

[meager spade]

actually state a question don't just ask for help

[meager spade]

@silent birch stop posting the same question in multiple channels, its against the rules of the server.

[silent birch]

OK so help me?

[velvet parcel]

Using a multicast event to create a save game file will make it so all clients will save a copy locally right?

[fringe dove]

does anyone know offhand if steam's IsP2PPacketAvailable, ReadP2PPacket, and SendP2PPacket are threadsafe?

[junior dragon]

Hi, Everything works fine in single player but when I try to run editor for 2 players there's exception in this method and AIController is null

this code is in non player pawn character which patrolling along patrol locations.

[fossil spoke]

AIControllers only exist on the Server. Your not checking your pointers, therefore your causing a crash.

AIController = Cast<AAIController>(GetController());
if(AIController)
{
    // ... code here
}

@junior dragon

[junior dragon]

Thank you. It works. I would like to ask more.

How do I know which part should be separated from client and server (for example in this case GetController should only be called on server)?

And how do people usually separate code that should run only on server? Do people use if-else similar to my cases or a better way?

[fossil spoke]

http://cedric-neukirchen.net/2017/02/14/multiplayer-network-compendium/

Have a read of this.

[junior dragon]

Ok, thank you.

[twin juniper]

how do I go about pawn possession in multiplayer? BP based, new at this and just learning the basics. Here is what I am trying, have also tried index 0. This is in my level BP, I have two pawns one with auto possess player player 0 and auto receive input player 0 and the other with the same for player 1. Only the server side works as I expect the client just spawns a new pawn. Don't understand the auto possess and receive input thing for multiplayer

Is the index 'reset' for client/server? So if I have a server and 3 clients then server will be index 0 and clients will be indices 0,1 and 2?

[fleet raven]

don't have pawns in your level, put player starts instead and the game mode will automatically create and possess pawns as necessary for joining players

[twin juniper]

Ok I'll try but surely there is a way to do it with pre placed pawns? Is my BP correct (aside from the specific index)?

of course it's wrong as mousing over 'possess' node it says 'authority only' 😉

[grizzled stirrup]

If you are doing healthbars for other players and have in world pickups that affect Max health, it's pretty much essential to replicate both CurrentHealth and CurrentMaxHealth, right?

[meager spade]

Depends if maxhealth changes

[grizzled stirrup]

Yeah it does

There could be hacky ways to update it locally

But it might just be better to replicate it

[meager spade]

Then yeah you would need to step it

Rep

[grizzled stirrup]

Cool thanks!

[grizzled stirrup]

Will COND_AutonomousOnly on a replicated property ignore any non playercontroller owned actors such as AI characters?

Trying to only replicate health via a health component for human players and not AI

Doesn't seem to work by setting to AutonomousOnly and I believe SimulatedOnly will replicate from AI

[meager spade]

so

Player 1 connects to server, he is Autonomous.

Player2 connects to server, he is Autonomous

Server Replicates Player 1 to Player2, this is Simulated

and vice versa

[grizzled stirrup]

Ah ok thank you so there is no real way to gate player controlled actors other than maybe a COND_Custom condition?

Could potentially disable replication on the health component if owned by an AI controller also actually

[meager spade]

tbh no harm in really replicating the property to AI

very small bandwith use

[grizzled stirrup]

It's just if there are 50 AI and they are all replicating 2 floats 10 times a second

Would that still be tiny?

[meager spade]

properties are replicated at frequencies

based on the update rate of the pawn

actor*

and they won't be at the same time

[grizzled stirrup]

In the case of the AI it's 10 times a second and the player is 60

the NetUpdateFreq that is

[meager spade]

we have 100 ai replicating a lot of stuff

and hardly impacts net usage

[grizzled stirrup]

Ok thanks, it must be the CMC eating up most of the bandwidth

[meager spade]

yup

[grizzled stirrup]

With 50 AI, it jumps easily up to 40 / 50 kb

[meager spade]

cmc is terrible

every tick it can send a update

altho this is Unreliable

it still gets sent

[grizzled stirrup]

makes me wish I had the time to look into writing a very barebones CMC

with only the absolute basics sent infrequently

For AI and other actors that don't need precision

Thanks anyway I'll keep the floats replicated to all

[meager spade]

also another thing

if a property doesnt change

it wont replicate

so unless health is changing it wont keep replicating it

[grizzled stirrup]

It's regenerating 10 times a second

So unless their health is full, it'll replicate

[meager spade]

sure but once its full it wont replicate no more

[grizzled stirrup]

Yep

And actually once a second sorry

So it shouldn't be too bad

[meager spade]

nope

we have health regen on our AI

and like i said, we have very small impact

with 100 ai

CMC is what kills us ATM

[grizzled stirrup]

Great to know. It does make sense when you think about the fact that it's only 8 bytes at most 10 times a second

Whereas the usage with CMC is way higher

Will have to look into ways to optimize it a bit

I have tried many tricks to shave off time on anim updates and skeletal meshes which works great in terms of performance but the bandwidth usage is still there with the CMC

Tried Nav_Walking movmeent mode and a few other CMC specific tweaks but not much difference in bandwidth

May have to override if possible and call some of those unreliable RPCs only at a fixed rate

[slender yarrow]

is there any way to retrieve an external IP when a dedicated server is ran? Like is there a function in some class that can get the IP of the host when a session is created?

[meager spade]

@silent birch again, you are asking the same question in multiple channels. Please don't do that

[tardy cosmos]

Hi hi, how expensive for the network is to replicate a float 20 times per second?