multiplayer

[chrome bay]

but for sheer walls it just means a smek

[thin stratus]

It was using everything

So even small pieces where traced and the drone just smacked into the floor

[chrome bay]

Ahhh yeah

simple collision ftw

[thin stratus]

Told client to make a custom collision for only the gravity stuff

And a second for actually colliding with stuff

So a very simple one for what we can drive on

Future will tell if that solved it, haven't gotten around to that yet

Also you still need to make a blog post about your 3D radar

ffs

[chrome bay]

hahaha

that's a USP man 😄

I actually wanna change it up a bit because I've decided I hate myself and want to to diagetic UI now

I played too much Elite

also VR etc.

can't wait to get a headset and find out none of my UI works anymore

[winged badger]

@chrome bay we had a monster jump up and down just placed on a map (client only), turned out to be a combination of NavMeshWalking and client side capsule just being a bit too large

scaled down the capsule for NavAgentProperties calculation only, and it was fine

[chrome bay]

Man.. don't even get me started on AI

Perhaps the most annoying thing about AI is that GetActorNavLocation() isn't virtual... I mean what the actual F epic

Make NavMesh basically useless unless you're stuck to it

[thin stratus]

@chrome bay But GetNavAgentLocation is virtual or?

[chrome bay]

Oh I can't rememeber... there was something that wasn't virtual and I really needed it

GetActorFeetLocation maybe

[solar stirrup]

Would this be the correct way to do inventory logic using a fast array serializer?

bool UInventoryComponent::TryAddItem(int32 Id, int32 Quantity, OUT int32& Remainder)
{
    // Return if we don't have the authority.
    if (!GetOwner() || !GetOwner()->HasAuthority()) return false;

    // Return if it isn't a valid item.
    if (!ItemManager || !ItemManager->GetItemFromId(Id)) return false;

    // Iterate through the inventory and check for slots that have the item already.
    for (int32 Index = 0; Index < Inventory.Items.Num(); Index++)
    {
        if (Inventory.Items[Index].GetItemId() == Id)
        {
            // more logic
        }
    }
}

I basically check for authority, if local doesn't have it I just ignore

server replicates to client anyway

then for when the client wants to do something i'd just call an rpc for the server to apply if normal

[marble depot]

hey, does anyone here know how could i get something like an event that would be called "Event OnInviteReceived" from the Steam API? there doesn't seem to be something like this in Advanced Sessions or in the steam sdk. basically i want to make a panel in the game that tells you "PlayerName has invited you to their party! join/ignore" so that you could join parties without having to shift-tab to get to the steam overlay.

[spare glade]

Is there another good source of documentation on replication graph besides the Epic livestream and the doc page?
I have shooter tutorial one also was just wondering if there were more sources to learn from
Or any1 good at replication graph who doesnt mind some convos on how it works

[worthy perch]

If I change a property on MyStruct every ~1 second, replication happens sporadically. If I call ForceNetUpdate everytime, then it'll replicate after every change (as it should imo).
Why would ForceNetUpdate be required if I'm not being net saturated and I have a decently high NetUpdateFrequency?

[meager spade]

1 second replication is pretty heavy for a struct

if its a big struct that is

tbh

doesnt structs only replicate what has changed?

[worthy perch]

doesnt structs only replicate what has changed? I've seen people say that, but someone else said, and I agree with him, that the entire struct is sent.

Also, for some reason my struct is only 4bytes despite having two floats an enum and an int16.

But even so, I don't understand why it forgoes replication under frequent changes without calling ForceNetUpdate.

[meager spade]

what is your updates rates?

[worthy perch]

15 NetUpdateFrequency.

Without ForceNetUpdate, the first ~2 changes happen, but the changes after that are completely not replicated.

It's just weird behavior that I don't think is caused by a mistake on my part.

[fleet raven]

replicating struct sends changed properties since last acked replication state as delta

[twilit swift]

Hey all, I'm trying to define some macros for steam dedicated servers as per the 4.22 release notes. I think I've set things up properly, but when my server tries to create a session, it can't seem to create one.

here's what my Server.Target.cs file looks like:

using UnrealBuildTool;
using System.Collections.Generic;

[SupportedPlatforms(UnrealPlatformClass.Server)]
public class MyGameServerTarget : TargetRules   // Change this line as shown previously
{
    public MyGameServerTarget(TargetInfo Target) : base(Target)  // Change this line as shown previously
    {
        Type = TargetType.Server;

        GlobalDefinitions.Add("UE4_PROJECT_STEAMSHIPPINGID=480");
        GlobalDefinitions.Add("UE4_PROJECT_STEAMPRODUCTNAME=\"MyGame\"");
        GlobalDefinitions.Add("UE4_PROJECT_STEAMGAMEDIR=\"MyGame\"");
        GlobalDefinitions.Add("UE4_PROJECT_STEAMGAMEDESC=\"My Game\"");

        ExtraModuleNames.Add("MyGame");    // Change this line as shown previously


    }
}```

Am I doing this properly? missing something here?

[gleaming niche]

@solar stirrup i use fastarrayserializer for my item containers too, but what I do, is on server side i keep them in a map as usual, but then i use the serializer only for replicating to client; but i don't put the actual item there. I just serialize the 5 run-time properties, and client side just makes copies from the item database itself.

so client side makes a fake item, for visual / prediction

and then it only needs to update the small stuff like count (if it's stackable), and which slot it's in, etc.

[solar stirrup]

@gleaming niche i mean player slot is basically just the item's id quantity and position so I'm probably doing the same thing as you

Which makes me glad because I'm in the wild with C++, most of my game dev work has been done in C# so far 😓

[meager spade]

most games replicate the weapon

its not that much info

how many players?

might want to also consider replication graphs

[velvet parcel]

Is it possible in blueprints to use seamless travel where everyone on the server travels with you to the next map?

Does advanced sessions plugin make this possible?

[steel cove]

You can call the serverTravel console command from BP.

[velvet parcel]

oohh thanks one sec.

Does the console command BP work in a shipping build?

[gray scroll]

No

[velvet parcel]

hmm that may end up being the only way to do it

[gleaming niche]

that's how I did it in last project iirc.

[velvet parcel]

umm it apparently seems to be the case that servertravel console command is broken

travel works though but it does not bring other players

[velvet parcel]

nm server travel does work, its just not happy in PIE

[worthy perch]

Just by the way, I figured out why my struct would not replicate upon frequent change. Basically, I was essentially switching true/false really quickly which, I assume, evaluated to no change and thus no need to replicate.

[thin stratus]

I got a Weapon that can sit on the PlayerPawn or on some random other Actor in the Level.
I got a pointer to that "owningActor". I want to know two things: Is a Player in charge of the Weapon and if yes, is it the local version of the weapon.
I could cast the OwningActor to the Pawn, but I wonder what other ways are there to not cast to a specific known class.

(c++)

I could use "HasNetOwner" maybe, is that "false" for something placed into the Level?

Also what does that do for a simulated actor

Hm GetInstigator() ? GetInstigator()->IsLocallyControlled() : false;?

[winged badger]

@thin stratus ```cpp
bool USolsticeObjectLibrary::IsLocallyControlled(AActor* ActorToQuery)
{
if (!ensure(ActorToQuery))
{
return false;
}

AActor* TopOwner = NULL;

for (TopOwner = ActorToQuery; TopOwner->GetOwner(); TopOwner = TopOwner->GetOwner()) { }

APlayerController* controller = Cast<APlayerController>(TopOwner);
return controller && controller->IsLocalPlayerController();

}

with minor alteration you could make it take a UActorComponent pointer too

i find it much more convenient then writing a customized query each time

mostly because i can eyeball the static call from orbit, making the code easier to read in stride

[thin stratus]

Right, that is for locally controlled. I have an instigator defined so mine works for now.
I still wonder how I can check on all clients if something sits on a client

Cause other clients don't have the PC

@winged badger

[winged badger]

you have IsPlayerControlled, or IsPlayerPawn, too

[thin stratus]

On actors?

[winged badger]

one of those 2 on APawn

return PlayerState && !PlayerState->bIsBot;

[thin stratus]

Hm

I guess for a Pawn it's relatively straight forward to cause a Pawn is either possessed or not.
And for other actors I guess I should just reference the Pawn again

[winged badger]

yeah

[real yacht]

has anyone build gamelift for android?

[velvet parcel]

What would be the first thing you guys would check if an advanced session was visible with multiple instances on one PC but is invisible to anyone on the internet or LAN?

[winged badger]

presence

[velvet parcel]

Its checked

should I uncheck it?

Presence and listen are both active. 😦

[winged badger]

i don't really remember, it was ages

but it is the first thing i'd check

it should show what its for in the comment

also, LAN checkbox

[velvet parcel]

hmm I wonder if LAN is the problem. I have noticed that apparently session stuff simply does not work if you do not have some kind of server to broadcast

like Steam

[shrewd frigate]

Hello. I need some help here going on with online multiplayer on Android. I'll. Like to know how possible it is to host an online session with Android for multiplayer. I don't really want to use Lan.

[shrewd frigate]

Does anyone know how I can go about it?

[thin stratus]

@velvet parcel Lan should still work. But you won't have any online sessions unless you use Steam or another Subsystem that provides MasterServers and is build into UE4

[velvet parcel]

lan isn't working either @thin stratus

Weird

[soft relic]

why wont this work for the client?

[bitter oriole]

Depends on ownership

[chrome bay]

Also, that RPC might arrive before the health value does

[soft relic]

runs from playercontroller

[chrome bay]

You should use Rep Notifies for that

[soft relic]

so what to do?

[chrome bay]

tell the variable to replicate using RepNotify

change the value in the widget in that function

I'd also suggest watching more tutorials and/or studying examples

[twin juniper]

Hi everyone. I would like to learn how to decrypt UE4 packets.

Where should I start ?

[chrome bay]

If you're talking about cheating, the last place to ask is in a chatroom full of multiplayer devs

[soft relic]

That worked, is this a bad practice?

[chrome bay]

yes

don't do that

[soft relic]

What's the problem with this?

[chrome bay]

Everything

A) You shouldn't change replicated variables on the client unless you have very good reason to (rarely ever)
B) You shouldn't use RPC's to send information about persistent state changes.
C) You have no guarantee whether the RPC or the variable will replicate first
D) You're using more than twice the bandwidth than normal variable replication.

I could go on

Study examples. To be any good at multiplayer coding you have to understand it yourself

[soft relic]

I do, but right now I just need a quick fix on that lol

[shrewd frigate]

Hello. Will it be possible to create a multiplayer feature using onlinesubsystemGooglePlay?

[bitter oriole]

@soft relic There is no simple answer because it depends a lot on your game

You need to decide who you trust to generate the authoritative value that will be used - client or server

If it's the client, you simply don't need to replicate the value back to him

if it's the server, you need to implement some kind of replay mechanism to handle conflicts

[twin juniper]

@chrome bay I'm talking about learning..

[chrome bay]

Either way the answer is the same, study the engine source code

[shrewd frigate]

Please How do I go about hosting a multiplayer session for a mobile game ?

[gray scroll]

what is the best option for going with dedicated server? AWS?

[chrome bay]

There's loads to choose from

We use Zues, G-Portal and Nitrado

Not sure there's a best option but Amazon are decent

Expensive though IIRC

[gray scroll]

What do the popular games like contractors or onward use? Do you know?

[thin stratus]

@shrewd frigate Android has no Session Subsystem exposed

You'd need to check if the actualy Android SDK has some stuff (probably requires C++)

Or check if there is a plugin

But you can't use the Session nodes

IOnlineSessionPtr FOnlineSubsystemGoogleCommon::GetSessionInterface() const
{
    return nullptr;
}

It's not implemented

[shrewd frigate]

ohh... thanks

[chrome bay]

@gray scroll no idea, you'd have to ask them.

[velvet parcel]

So in the player state I tell each client to get their account name from a save file. But it does this weird thing where it shows MY name right before it they fully connect and switch to their correct name. Is there an easy way to fix that?

[thin stratus]

BeginPlay calls on everyone when it's a replicated class like the PlayerState

e.g. if you have 4 players, it calls 4 times on every client for their own and the 3 other playerStates

[velvet parcel]

ah 😃

Hmm maybe pipe it through gamestate and run on owner

Hud > player Controller > player state
That seems correct. Hud is only run on client
But it can then talk to player controller and get the player state.

[shrewd frigate]

So just to be sure, my only option for a mobile multiplayer game on android is to build a stand alone server? Since Google's Session Interface has not been implemented yet

[chrome bay]

The Server part isn't really a problem, finding servers and connecting to them is

The session system is responsible for advertising and being able to find servers via the internet, which requires some support. Google might have a system for that, but if it does the engine has no implementation for it so you will need to create one and link it up with the google SDK.

Otherwise, you will need to provide your own framework (or wait until Epic finish EGS - whenever that is)

[meager spade]

EOS?

[chrome bay]

Or that if that's what it is

[meager spade]

surprised there is no UE4 plugin for it

made by epic considering its there framework

[chrome bay]

I think there probably will be once it's a bit more fleshed out, you can't really do much with it at the moment

[meager spade]

yeah but the system must be functional as they use it on Fortnite, suippose thats more internal tho

[chrome bay]

yeah, I think the public-facing matchmaking etc. part is still missing

[shrewd frigate]

Okay, I think I'll go with creating an implementation and linking it up with google's sdk. I'll do further research on this. I dont know how long it'll take for EOS to be supported on mobile.

[lost inlet]

EOS is super early, I'm surprised they didn't even have a UE4 plugin at launch

even now, it's still only a flat C API right?

[meager spade]

Yeah but easy to put into ue4 just lacking features

[winter plover]

so my NetMulticast RPC isnt firing, and Im not entirely sure why

I made sure that it's run serverside and that the actor is replicated

I heard somewhere once that RPCs get dropped if an actor is outside of a players range

the actor in question is just a manager thingy without a transform

would that be relevant?

[cerulean escarp]

hey @meager spade I'm 100% sure I set up my animation network code in the wrong place and the animations don't even replicate to other players, could you help me? I put the animation stuff in my FPSCharacter BP and here it is:
https://i.imgur.com/3h1JuhT.png

the ServerAnimate RPC is called from an event tick node

[meager spade]

So you set the book on tick and anumgraph plays the running?

[cerulean escarp]

yes

[meager spade]

Bool

And it doesn't?

[cerulean escarp]

it plays on the client but not the other players screens

[meager spade]

You shouldn't need to multicast the bool

Set running bool to replicated

And just tell the server you see running

Other clients will get the replicated value

[cerulean escarp]

so skip the multicast entirely?

also IsRunning is replicated

[meager spade]

No need for it its redundant rpc

Server will replicate that property to all simulated clients

As long as your animgraph is pulling that value from the player every tick

It will sprint on all clients

[cerulean escarp]

I took away the multicast and now no animation plays

[meager spade]

Yeah so you have other logic issues

[cerulean escarp]

hurray

[meager spade]

How are you getting the isrunning into animgraph

[cerulean escarp]

well I'm taking the IsMoving bool from my character and if it's true, I'm casting to the anim bp and setting IsRunning to true, and vis versa

[meager spade]

Also how are you checking if the player is running ?

[cerulean escarp]

I'm checking the velocity

if velocity is > 0 then IsMoving is set to true, which should set IsRunning to true

[meager spade]

err hmm

IsRunning is not Sprinting?

IsRunning is the normal speed?

[cerulean escarp]

yeah it's just a flat out run

so yes normal speed

[meager spade]

so cant you just have the animgraph check for IsMoving bool?

if you don't specifially need IsRunning? or IsRunning togglable?

[cerulean escarp]

I tried having the animgraph check for IsMoving but it caused the animation to play on all characters

[meager spade]

o_0

[cerulean escarp]

yeah ikr

[meager spade]

what animation?

like it plays it regardless if the player is moving or not?

[cerulean escarp]

every character copied whatever animation I was doing

at the exact same moment

[meager spade]

thing is

your animation should be decided via your movement speed

using a blendspace

[cerulean escarp]

yeah I'm using that system

both direction and speed

[meager spade]

and that replicates by default

so why are you setting IsRunning?

[cerulean escarp]

when I had the blendspace with the movement and idle and all that, whenever I moved it would copy the animation over every character, so I put in a state in my state machine called Idle that would transition to the movement blendspace when IsRunning was true

so that way the other players wouldn't copy my movement

[meager spade]

they should not copy your movement

which makes me think you did somehting wrong

in your animbp

and without seeing it

i cant help

[cerulean escarp]

I'll take a screenshot of it

here's the event graph: https://i.imgur.com/Qlkk8cw.png

[meager spade]

dont use

GetPlayerCharacter

use TryGetPawn

i had a feeling about that

thats why i was curious

[cerulean escarp]

omfg the video lied to me

yeah it works perfectly now

and is replicated

thank you 😄

[meager spade]

np

[solemn junco]

Hey y'all, has anyone tried encrypting their network traffic with something like OpenSSL?

Looks like UE doesn't have "easy" support for it

[fleet raven]

there is a "packet handler" for encryption, multiple actually

maybe you can make your own also

[solemn junco]

I wonder what would be the easiest way to encrypt all UDP traffic

[fleet raven]

probably turning on the packet handler

[terse dawn]

I seem to be having some issues that I can't quite figure out how to get around.

When I spawn a pawn from a Pawn (by pressing an input key) using IsLocallyControlled , I check on SwitchHasAuthority, then RPC call (or not if authority) to Spawn the pawn I want. This has the desired affect on the spawned pawn (all UMG widgets work correctly)

When I spawn a pawn from GameMode directly or from the PlayerController using IsLocalController, I can't get the widgets to work correctly at all. Even spawning them in BeginPlay of the new Pawn (using IsLocallyControlled before Creating Widget) doesn't seem to make things work like it used to.

Widgets do spawn correctly. It's the logic inside them that's not working right. What am I missing here? My assumption was that all widgets are client-only, so no matter what method I used to spawn the pawn itself, everything should be fine.

The only way I can seemingly get things working is by Pressing an INPUT button on the new pawn. But I want the widget to spawn and work just like it does without having to press an Input key logic. Even moving the Logic over to PlayerController, I still have to press a button with IsLocallyControlled branch, then spawn the pawn, then I get the widget and the widget logic working correctly.

Obviously (I think), if I am using an Input, that means I am using the client-side pawn. And BeginPlay does two Begin Plays, one for server and one for client-side pawns. So I has assumed that by using IsLocallyControlled would solve this issues in the new pawn. But nope. Any help would be greatly appreciated, thanks!

I should also add. That clients do use the Widget correctly. The Listen Server does not. (unless he spawn the pawn manually)

[fleet raven]

is there a callback for when a replicated actor is destroyed by replication on the client side?

can't seem to find any other than the normal destroyed

aha UObject::PreDestroyFromReplication

[jade gazelle]

Does it generally make more sense to have enemy AIs inherit from pawn as opposed to character? It seems like I’m constantly fighting against the CMC in my characters but I’m not on any position to write my own custom player movement component. I figure for enemies though there is much less need for it?

[winged badger]

there are few on the marketplace, i think

not sure how good or useful they are

[jade gazelle]

Well, I’m fine with using the CMC for now for player characters

Since they are all bipedal and human shaped. Im more thinking about AI, and if there is any benefit to having the CMC or character class at all on AI pawns

It seems like it would be a lot less restrictive to have my enemies inherit from pawn and not be limited by things like the capsule. But I’m wondering if I would be losing anything important that I’m overlooking

The networking aspects of the CMC seem mostly irrelevant for AI pawns, unless I’m not understanding them correctly

[winged badger]

NavMeshWalking will cut down the CMC performance cost on AI

but its not suited for every camera

since AI then effectively walks on navmesh, which is some 30UU above the floor

doesn't bother you with top down camera, but i wouldn't go that way for an FPS game

[jade gazelle]

Not sure I’m understanding. If I’m using navigation wouldn’t the AI walk on the navmeah regardless of being a character or a pawn?

[winged badger]

the difference is on how CMC detects the what it considers to be the floor

[jade gazelle]

And overrides the navmesh y axis ?

Or something along those lines?

[winged badger]

its a capsule sweep vs project point to nav

first one tends to accumulate on the cost fast, when there are lot of AI around

[jade gazelle]

Interesting. I’ll have to look into that

I just want to try and get away from the character class wherever I can because I feel like I’m regularly running into instances where I can’t do certain things with it

[winter plover]

sooo my replicated actor randomly stops ticking and executing NMC RPCs serverside for some reason as soon as I set bAlwaysRelevant to true in the constructor

clientside instances seem to run fine, but dont appear at all if bAlwaysRelevant isnt set

Im kinda stumped as to why this could be

[ember cloak]

Has anyone played around with figuring out some sort of host migration? Ive been looking around and haven't really found anything.

[somber glade]

I'm going to post this here instead as it's more relevant here: Truly bizarre behaviour here. We have an actor with a widget component that holds the lobby menu for a VR game. Only the person hosting, the server, can see this start button. If you host a match alone, it works fine. But if another person joins, it becomes odd.

the host can click on this button 20 times and it won't work. Until both the host and the client are pointing at the button and clicking together. The actor it's on is replicated (see screenshots) and this widget button calls a function on the game mode that is set to run on server, which calls servertravel.

[glossy wasp]

@ember cloak In theory when old host goes through the UI to quit, select a new host then get their IP to send to clients to auto reconnect (with a timeout duration) and save the game state out to a json on the new host to start a new server and restore it?

[somber glade]

So apparently i had a weird issue with gamemode gamestate type mismatch. That seems to be fixed, and it is sort of working. The only problem now is that when the client joins the lobby, their player controller doesn't work properly. It's not spawning them into an avatar and instead leaves them floating outside the level. But they do show up in the lobby, and on the player list. The host can then start the level, and the host seems fine, but the client's avatars are completely messed up. Previously the client could join the lobby with an avatar just fine, but it would crash on moving to the level on game start

Previously my LobbyGameMode was derived from gamemodebase, and my gamestate was gamestatebase, but my main game mode was gamemode. So i changed everything to gamemode and gamestate.

That seems to have solved the crashing but has left the client avatars messed up

[timber garnet]

Question:I'm NOT using Unreal's Replication. I've got my networking in place and two players in a game. But for some reason the client character can't receive controller input (when i run two instances on the machine). Im thinking replication (ie authority) is causing the issue. Any thoughts?

id like to use the easy "2 player mode" without any unreal replication

I think it is because Possess only runs on the server, but that these PIE instances are both running as "non-authority"

[winged badger]

if you jury-rigged your own networking its hard to guess as to what you modified

but

controller needs to SetPawn, which happens clientside in OnRep_Pawn, and the client also needs a replicated PlayerState

Pawn also has replicated Owner, Controller and PlayerState members

if any of those fail, unreal won't work right in network envinonment

[timber garnet]

ok thanks this is super helpful

[timber garnet]

So yeah the issue is when in test mode with multiple PIE running, Unreal wants to force me to use the Authority model. If I build the game as standalone clients (ie singleplayer), Possess works because the client has authority. The ONLY thing I need is to force client-side possession while in Unreal multiplayer test mode

ill probably have to build some listen server replication just for development purposes since building clients takes forever

[winged badger]

not really convinced that custom networking with unreal is the best way to go

engine will throw bomb at you for the entire development most likely, does that even when you use unreal networking

[gleaming bobcat]

Hey, What is the correct way how to replicate larger data then UE supports. Error: Final partial bunch too large. Do I have to manually split data and send them by RPCs ? BTW I need to replicate the data only once

[somber glade]

So I'm in a situation where clients aren't getting an avatar on join. Avatars are spawned from the player controller. Begin play checks the environment, initiates HMD and then spawns an avatar dependent on those things. As a client I think begin play isn't called. I tried to override postinitializecomponents and call begin play only on clients, but that hasn't worked. Is there a Blueprint function that I can use on a PC that clients can run when they join a level that is set to listen?

[scarlet moat]

Can somebody please help me with this quick question? Is there a way to prevent a hud from being created when i use the "create player" node. thanks

[thin stratus]

Create Player usually spawns a new PlayerController

So if you have the creation code in there, then you need to stop that

@scarlet moat

@somber glade BeginPlay is def called when they connect the first time

[somber glade]

hmmm... okay I'm adding some debug to be sure. And building another version.

THe host is definitely calling begin play.

but it seems like the clients aren't on join.

[thin stratus]

What exactly does " Begin play checks the environment, initiates HMD and then spawns an avatar dependent on those things." mean?

VR HMDs are a local thing

[somber glade]

VR expansion plugin. There isn't a default pawn. So it checks if an HMD is attached, checks tracking, and then inits the HMDthen after that it spawns the appropriate pawn

[thin stratus]

Not a Multiplayer thing, so whatever is checked has to happen on the Client.
The Avatar is most likely something replicated, a character or so, so that should happen on the Server

Can't you check the Tracking stuff upfront

Before joining?

And simply send a few options to the Server on Join

And then handle spawning the avatar in the gameMode with the given options?

That sounds way cleaner and more logical

[scarlet moat]

@thin stratus thanks. i'll take a look

[somber glade]

I could do that I suppose. I've just been following the way this is set up since it's recommended as a starting point for VR in unreal.

But if begin play is being called, then I can't figure out why it's not spawning an avatar and possessing it regardless.

It was actually working earlier, but that was when i had a mistake. Which makes no sense. I accidentally had the game mode set with a parent of AGameModeBase when it should have been AGameMode. When I fixed that, the avatar stopped spawning.

[thin stratus]

Is your GameState also GameState instead of GameStateBase?

Cause you can't mix that

[somber glade]

Gamestate is gamestate.

So I fixed the gamemode, because the other gamemode was agamemode

But after fixing it so that both game modes and the gamestate were matching correctly, that's when the client avatar stopped spawning.

when it was not matching the client avatar was spawning and working perfectly fine.

[thin stratus]

Yeah but it should match either way

At that point you probably have to show the code that takes care of spawning

I'm afk now though for an hour :P

[somber glade]

okay well I'm running a test right now to see if begin play fires when the client joins or not

I'll report what i find

okay so begin play is running

The begin play just runs some checks to make sure an HMD is present and that tracking is valid. If it is, it runs this other function which is set to run on server and is checked reliable. This is also on the player controller

This function first gets all the playerstarts in the level, and picks one at random

it gets the transform of the playerstart and spawns a pawn at that spot, possess it and then runs some console commands

these are just some graphic related things

If you're curious this is how the lobby level is opened when hosting

[somber glade]

I just added a ton of these prints to the functions on the player controller. This RPC to the server, never gets called that I can see. Looking at both the host and the client, these print strings never execute after joining the lobby as the client. When the host joins the lobby they get executed.

[somber glade]

@thin stratus So there may be a timing issue here. I added a 2 second delay before the RPC call, and the avatar spawns, but it's busted. Normally my anim BP attachs the heads and hands to my HMD and motion controllers, but it just sits there like this not getting any tracking coordinates I guess. I do have input though. I can use a button on my motion controller to call up an in-game menu (the event is on the avatar, so I think I'm possessing it).

This is the avatar from the point of view as the host. As the client, I see basically the same thing except it's floating about 60 cm off the floor

[thin stratus]

So you basically call stuff and hoped that everything comes in timed

:D that's not a thing for Multiplayer

E.g. the RPC you call when spawning the actor

Can totally call before the pawn replicates

If you want to call stuff like that, you want to utilize given OnRep calls

Like OnRep_Pawn in the Controller

If that calls, you know the pawn is replicated

Then you also don't need the rpc

@somber glade

[somber glade]

I'm somewhat new to this, which is why I was using the VR Expansion plugin because it's reported to be all set up and working for multiplayer.

[thin stratus]

Wouldn't bet on that if you don't know the person who created it

I'm working day on and day off on this stuff and I still have a lot to learn

But a golden rule is, that if two events cause replication of sorts, you can't bet on them happening in order

E.g. Replicated Variable and RPC

Or Replicated Actor and Variable/RPC etc.

[somber glade]

Hmm okay. I'll keep digging and see if I can sort out what's out of whack here.

Thanks 😃

[thin stratus]

If you need two things to be available at once you either send both things in one or you utilize things like OnRep

I would suggest you clear that stuff up

And go step by step and check all replicated parts

And make sure everything happens the way you want it before you add the next step

[winged badger]

@somber glade what calls ReturnHDMStatus?

[somber glade]

The player controller calls that.

it gets it's HMD status, makes sure the tracking is valid and returning values, because it needs the offset from those to spawn the avatar. the avatar has to be spawned with an offset from the HMD tracking

once it's got that, it makes the RPC call to the server.

it uses that offset and rotation along with the transform of the randomly selected player start to create a transform for spawning. Without that, it won't spawn in the proper location.

[somber glade]

Should onposses fire only on the server or both the server and the client?

so as a bit of mystery. The Player controller is reporting that it is controlling the avatar. But nothing on the avatar that should fire when Locally controlled is working.

[thin stratus]

OnPossess calls on the Server

Client has OnRep_Pawn and OnRep_Controller (depending on what class you are in)

That is C++ only though

[somber glade]

I have a base C++ class i can use if need be.

[thin stratus]

That's good

You can override the OnRep_ functions

[somber glade]

So.. if I my PC is reporting that it is controlling the character..

[thin stratus]

And add a second function like this

[somber glade]

why isn't the tick running?

[winter plover]

Where's the best place to put a global manager actor reference?

I tried a static pointer first

but that caused issues

because in editor theres only one for all instances

[somber glade]

tick must not be enabled for some reason

[thin stratus]

// HEADER
/** Called when Pawn is replicated. */
UFUNCTION(BlueprintImplementableEvent, meta = (DisplayName = "OnRep_Pawn"), Category = "Core")
    void K2_OnRep_Pawn();

virtual void OnRep_Pawn() override;

// CPP
void AHLPlayerController::OnRep_Pawn()
{
    Super::OnRep_Pawn();

    K2_OnRep_Pawn();
}

Same for other OnReps

Not sure why your tick isn't running

@winter plover You have a bunch of static actors like GameMode and GameState

If it needs to replicate, GameState, if it onyl needs to exist on teh Server -> GameMode

[somber glade]

the tick is set with a bool to only run when locally controlled, so I stuck a print in there to print on the client that it was ticking, but got nothing. That might be why my avatar is all funky

[thin stratus]

Might even qualify as an ActorComponent

That's what I use for most of my managers

[winter plover]

it needs to exist both server and clientside

but the reference possibly not

Is there anyway to access the gamemode actor from a static context?

say I have a static function "Make Explosion at X"

I want it to talk to the manager actor and call a bunch of privates

[thin stratus]

As long as you have a reference to the world, yes

You can always to GetWorld()->GetAuthGameMode()

Which is of course only valid on the Server

But your Static Functions needs the world ref

So whatever uses the function has to provide that or serve as context

[winter plover]

mhmm k

actually I might be able to hack around this

actually no nevermind

that would be static pointers again

and I think im done with those for now lmao

I spent a whole day wondering why my server side actor would suddenly not respond to anything, but one particular clientside version would

turns out the server was invoking the functions on the clientside actors

because it was running in editor, and thats where my pointer was set to after replicating

[timber garnet]

Does anyone know if UE4 has any type of built in Protocol Buffer or Flat Buffer. Implementing Protocol Buffer manually has been a huge pain, especially since I'm building for iOS and Windows for development

[somber glade]

@thin stratus Is there something that would make a possessed pawn not tick? I've checked my code and the only place tick is disabled is for a mesh setup, it's disabled, the correct mesh applied, and then the tick is re-enabled immediately after. Beyond that tick isn't touched on the character. So could something else cause it not to tick?

it is set to start with tick enabled

[thin stratus]

Something like overriding BeginPlay in c++ and forgetting the Super:: call

[somber glade]

Nah, I haven't touched the c++ for that at all.

and tick is otherwise working for these characters.

just not in this particular situation.

if I host with this avatar, the tick works just fine

Here is the output when I host a session with this avatar. Only when it's the client is it not ticking

[timber garnet]

@somber glade i had a similar issue last night, it was related to the possessed pawn not receiving input, i had to activate input after i called Possess. I had been calling it before Possess and it never restarted

[thin stratus]

@lament cloak Use a fairly small instance on AWS First. Run one Server. Monitor the Server's RAM, CPU and Bandwidth usage when empty and when completely full over multiple minutes of time

Repeat with a stronger instance

Do the math and host x servers on the instance and see if that still fits when all servers are full and used

tada, you know your hardware

[timber garnet]

@lament cloak this doesn't answer your specific question, but I did as Cedric mentioned just for a mobile game, and to have a single server running 24/7 with an assummed two players at any given time, was $384 a month to start

Its why I moved away from Unreal built-in networking

[thin stratus]

That sounds wrong

[somber glade]

@timber garnet Input seems to be working. I have a little pop-up menu set to a key on the motion controller. That event is on the avatar, and if I push it, the menu pops up

[thin stratus]

Idk what kinda of huge mobile game you have, but our arena shooter can run I assume 6-8 Servers on a 4 core CPU with 6GB RAM

Which costs around 170€ per month iirc and each server has up to 8 players

[timber garnet]

Well im definitely no expert, but just uploaded the dedicated server to Amazon Gamelift

[thin stratus]

I hope you used Linux

[timber garnet]

it was a windows instance

[thin stratus]

Cause you really don't want to ever host Windows

Yop

[timber garnet]

but Unreal replication and dev ops is overly complex. im using Nakama now and it has been a breeeeze

i dont mean client server replciation code, i mean the whole deployment process

[thin stratus]

Replication has barely anything to do with the Server though

Only Bandwidth

We tried the game with 8 bots

and with 8 players

and only the Bandwidth was different

Yeah I know, but even if you do matchmaking you have to check what instance you need via a static one first

So it's the same process

Matchmaking instances are too hard to access and check

Also the dev process in uploading to GameLift every time you did a change is stupidly long

[timber garnet]

i wanted to die during that process

[thin stratus]

Specially if something breaks

And the only instance you are allowed ot use locks up

Yeah we moved from GameSparks to PlayFab

And PlayFab uses Azure

I wouldn't recommend any of them

But GameSparks is too expensive

And I haven't used GameLift alone

So we moved to PlayFab and since Azure comes kinda with it we use that

Yeah, it's a shitty expensive to do that kind of stuff

[timber garnet]

Again I'm not expert, but i moved REALLY slow with GameLift and dedicated servers. Especially since UE4 has little support/docs for anything besides a Steam game.... Now I'm using Nakama and you get realtime multiplayer, leaderboardss, matchingmaking, etc and its open source

[thin stratus]

If it would be my game I would never have gone that route

Again, GameLift isn't really for realtime multiplayer, leaderboardss

It has Matchmaking by now iirc

That's why we used GameSparks in combination

[timber garnet]

@lament cloak https://heroiclabs.com/ worth looking into

[thin stratus]

Depends on if you have the skill and time

You still have to host the Servers somewhere

So you won't get around the costs anyway

If you don't have money on the bank you don't need and are open to waste, don't do something like this

Cause if your game doesn't get enough players, the whole thing was for nothing

[timber garnet]

Haha yeah multiplayer is no hobbiest pursuit

most complicated stuff Ive ever done

[thin stratus]

Don't get me wrong, Multiplayer is all fine, if you stick to ListenServers or deployable DediServers

So your players host them

You sell the game for a flat price

no hosting costs

tada

[timber garnet]

haha win win

[thin stratus]

Yop, just saying it's pricy and a lot of work

[timber garnet]

we're building a match based game like Clash Royale, and spinning up dedicated servers for each very small 1v1 or 2v2 match just was not realstic for our small team

[thin stratus]

That's why most studios that do it are bigger than what most people here have available

Well yeah that's what my client will use

GameSparks indie option is garbage by now

[somber glade]

NVM I just realized that begin play printed on both server and client

so that isn't it

[thin stratus]

@chrome bay Heeeey, 4.23 Preview with Chaos is there.

[somber glade]

and beginplay is not overridden anywhere in the base class

nor is tick

[somber glade]

This seems like a begin play issue. I enabled "tick before begin play" on the character and tick was working this time. It didn't fix the gimped avatar, but it did make him tick

@thin stratus

[chrome bay]

oooooooo

time to look at the runtime...

[real yacht]

can anyone help here. i'm using gamelift, and creating session, everything is on server (with lambda) on PC build client can openLevel with ip_address:port

but on Android open level with that ip_address:port doesnt work anything

what can be a problem? do i need somehow to verify that player?

[timber garnet]

doesn't Android require special permissions for internet access

<uses-permission android:name="android.permission.INTERNET"/>

[real yacht]

i'm not sure, because when game starts, i'm downloading some data from server

so that works fine

[somber glade]

@chrome bay Was that directed at me?

[chrome bay]

Nah Cedric

Oh NVM, you need to download 4.23 from gitHub to use Chaos. blergh

[real yacht]

anyone advice?

[glass plaza]

What would be the proper way according to the engine to set a player as a spectator?

[split gust]

probably done in a custom GameMode code

[high current]

@glass plaza player controller

Should do the actual spectating spectating logic, and GM should probably control who gets to spectate and who doesnt

[ebon nimbus]

having an issue where my client is getting bumped out into the default map(main menu) instead of the lobby it's trying to load. Big digging into it for about a week now and haven't made much progress in terms of finding out the problem. Here is a snippet from the log that i think is the most descriptive of the issue.

https://gyazo.com/faf915b1eb051c5bcfd599655059ab2f

if anyone could help me make sense of it, I'd be grateful. Right now I can't really piece together why it would load my lobby map, just to immediately do a join request for the default map

[somber glade]

Today on the weird and wonderful: In a lobby (openlevel with listen) a FPS avatar (spawned from the VR player controller when no HMD is attached) hosts a match. a client joins. This Client has a VR headset attached and gets a VRavatar. The FPS Host clicks "leave lobby" and goes back to the menu, kicking the VR client back to its own menu. All is right with the world.

Test 2: The FPS host creates a new match. The client this time, runs with -nohmd and connects to the match using an FPS client. (note that the FPS avatar and VR avatar both derive from the same C++ class and are controlled by the same kind of player controller). This time the FPS host decides to leave lobby. however upon clicking the button. Nothing happens. He clicks it 20 more times and nothing happens. The FPS client decides to leave the lobby because he's had enough of this and is instantly sent back to his menu. After the FPS client leaves the FPS host clicks leave lobby one more time and is instantly sent back to its own menu.

How in god's name is a menu button not responding depending on what type of avatar the client has possessed?

These are the menu buttons. The server start also refuses to run awhile the FPS client is attached. It's like the menu just stops working because the client is using an FPS avatar, which has no bearing on the menu at all

[thin stratus]

@somber glade Clients also need to clean up their Session

This is not a Server only thing

[somber glade]

Yes I know that but that's not the issue here the issue here is that when the client has a certain Avatar connected then the host can't use the lobby buttons those FPS avatars have no code in them related to the menu or the lobby or buttons or anything else so as long as that first person Avatar is connected as a client the host can't push any buttons if a VR client is connected the host can use the buttons as as soon as the FPS client leaves the map suddenly the host can push buttons again so that makes no sense

[thin stratus]

Yes I know that Yet you are filtering the Client :D

Well then put print strings in

Check if the button press fails or if some code after the press fails

[somber glade]

The client can kill it's session on it's own time

That's there for when the host leaves to kill the session for everyone

[thin stratus]

That only kills the hosts session

If you don't call DestroySession somewhere else for the client, then their session is still active

So they can leave, but not reconnect

But yeah, it's not the issue, just telling you about it

As said, put print strings in

[somber glade]

yeah I had to step out for a bit I'm just on my way back now so I had intended to put in strings but I would I was just mystified as to how the presence of a particular Avatar in a level could stop buttons from working when there's no code and it related to it so I'm very interested to find out exactly what it is about this Avatar that could have make a menu button stop working I just you know I just wondered if anybody had ever seen anything like that and what a possible cause of something like that could be

[somber glade]

@exi well I just tested it. I put print statements on the event on the Avatar. the event is part of a widget interaction. As it is a 3D widget. I put them when the event is called and after the button press executres:

@thin stratus I also put print strings on the lobby widget. As soon as the button is pressed and after the code runs

and it is just as I expected

After the FPS avatar client joins, when the host presses the start button, he gets the print indicating that he's trying to press the widget and that he just did press the widget.

Neither of the prints on the button run.

I tried pressing it as the host 5 times.

The client pressed the "leave lobby" button and he got both prints from the avatar and both prints from the button

[thin stratus]

So your UI Press are actually not UI presses but Gameplay presses converted to UI via the Widget Pointer

[somber glade]

after the client disconnected, the host pressed the leave lobby button and he got all prints and left the lobby

[thin stratus]

Are you using Click or Pressed for the Buttons?

And are you setting the InputMode somewhere?

[somber glade]

press pointer key

[thin stratus]

No i mean in the Widget

[somber glade]

on clicked

[thin stratus]

Try Pressed

Just to be sure

And make sure your Input Mode is properly setup

[somber glade]

Yes, but this only happens with 2 FPS avatars. if the client is a VR avatar the host can click leave lobby right away

I'll try pressed though

[thin stratus]

Yeah something somewhere you are doing wrong :D

Pretty hard to debug from afar

[somber glade]

I guess that, but there is really no code anywhere on these avatars that should impact those buttons

both fps and VR have the same base class.

[thin stratus]

FPS is also using a 3D UI?

[somber glade]

Yes they have a widget interaction same as the VR avatar does

with the same settings and same code to run it

[thin stratus]

Yeah I would suggest using Pressed and making sure the InputMode is, I guess Game

Or GameAndUI

And then see if that does something

[somber glade]

It's a VR project, I don't think input mode has been set anywhere in the game.

Nope there isn't a single set input mode node anywhere in the project.

[thin stratus]

Well then make sure you set it somewhere so it's under control

[somber glade]

@thin stratus Good call. Press fixed it

thanks man. That solves one mystery

I still need to figure out why my clients are crashing on servertravel

There is absolutely nothing useful in the log or dmp file except "unhandled exception".

[raven tinsel]

Hey guys, I am trying to create a custom network channel to send my own packets directly to the clients to be able to send big chunks of data. I am using FOutBunch to send the packets and it works, however I am only able to send ~200 bytes per tick (20 ticks per second) until the engine just stops sending data to other channels. Also pass a certain point I get overflow errors if for instance I try to send a big array of data (of ~0.5MB). What can I do to overcome those issues? ~200 bytes per tick doesn't seem like much right?

[chrome bay]

The replication system isn't really designed for sending bulk data, it's more about sending tiny packets often. Might be worth looking at sockets directly

Think the max element count for an array is 2,048 elements on the network. Look at FRepLayout::SerializeProperties_DynamicArray_r

Max memory is 65536 bytes IIRC

[raven tinsel]

@chrome bay Would you recommend opening my own tcp socket then? I am worried that it might be a pain for players since they will need to open multiple ports in order for the multiplayer to work properly

[chrome bay]

To be honest for big chunks of data there isn't really any other option. The game-level replication system just isn't designed for it

If the data only needs to be sent once, you could send it at game startup, and break the data into pieces using RPC's to send it.

[raven tinsel]

Hmm.. would it be possible to use the open connection to send packets through the raw socket (with the send function) without the replication layer?

[chrome bay]

I don't know to be honest, I've not tried it

[somber glade]

is there a breakdown anywhere of what runs and in what order when seamlesstravel is called on a server?

[winged badger]

@somber glade there is a pretty good chance you have some widget or something thats not cleaned up properly geting instantiated on the travel map

[somber glade]

I'm having some issues finding out what happens on the travel map.

do begin plays or anything like that get called?

[winged badger]

is it c++ project?

[somber glade]

Base is C++ yes

[2019.07.11-09.50.55:565][946]LogStats:     SeamlessTravel FlushLevelStreaming  -  0.001 s
[2019.07.11-09.50.55:566][946]LogWorld: Bringing World /Game/Maps/HSTransitionMap.HSTransitionMap up for play (max tick rate 0) at 2019.07.11-18.50.55
[2019.07.11-09.50.56:490][946]LogWindows: Error: === Critical error: ===
[2019.07.11-09.50.56:490][946]LogWindows: Error: 
[2019.07.11-09.50.56:490][946]LogWindows: Error: Fatal error!
[2019.07.11-09.50.56:490][946]LogWindows: Error: 
[2019.07.11-09.50.56:491][946]LogWindows: Error: Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0xe31708e0
[2019.07.11-09.50.56:491][946]LogWindows: Error: 
[2019.07.11-09.50.56:491][946]LogWindows: Error: [Callstack] 0x00007ff7df5aa967 UnknownFunction []
[2019.07.11-09.50.56:491][946]LogWindows: Error: 
[2019.07.11-09.50.56:513][946]LogExit: Executing StaticShutdownAfterError```

that's the log

[winged badger]

cook it, start the visual studio, switch target to DebugGame

press F5

[somber glade]

only happens to the client.

[winged badger]

join another game

and see what happens

VS will throw a breakpoint

[somber glade]

Yes I did that once already. But I'll try it again and see if it gives me anything different.

[winged badger]

if its a travel map or not, you can see

just get to any component in Locals

expand it to UActorComponent

find WorldPrivate variable

[somber glade]

I'm just pushing a build to the remote machine so I can attach debug

[winged badger]

i had some widget components getting instantiated on PlayerStates with no context

in my case, it was crashing the listen server host too

solve was cleaning them up in PreClientTravel override

[somber glade]

It's VR. So my lobby is a static mesh, 4 player starts, an actor that holds the lobby widget, and that's it at this point.

[winged badger]

if that actor persists thru the travel

might be your cause

[somber glade]

That's attached to a built version of the game

it does mention uscenecomponent.

[covert gorge]

Does anyone know if there is anyway to call a server RPC from and actor that is not a pawn being possesed? I have tried binding to a dispatcher defined in the Player Controller, but it didn't work

[somber glade]

So how can I make sure that actor is destroyed in preclienttravel?

is that on the gamemode?

@winged badger I looked this up. It seems that it's normally used for when widgets are on your viewport. Instead of simply clearing my hud. I should have the PC cast to the widget holder in the level and clear the widget, or should I simply have the gamemode destroy the actor on processclient travel?

[winged badger]

unless its owned by one of the actors that normally persist

it shouldn't

[somber glade]

it's not. the item is already in the level it's not spawned.

[winged badger]

i assume you didn't manually add it to the list of persistent actors

but thats why you need to hit that breakpoint

[somber glade]

when the lobby opens the gamemode casts to the instance gets the server info and casts to the holder and sets it on the widget.

[winged badger]

because im just guessing until VS shows you whats happening

[somber glade]

I'm thinking it's in BP, so I'm not sure it's going to show me anything.

but I'll try that now

@winged badger pretend i'm an idiot here, I know it'll be hard, but when you say cook it, are you simply referring to building it?

[winged badger]

it will be harder to read

but it will show you some things

package project

[somber glade]

oh well yeah that screenshot I gave you above is the output

on a packaged build

other than mentioning uscenecomponent there isn't much there.

okay i got something this time

@winged badger

[graceful cave]

@covert gorge have the server set the owner of the actor to the client's player controller

[covert gorge]

@graceful cave do you mean by possessing it?

[graceful cave]

no

call SetOwner on it

[covert gorge]

the actor i am talking about is a child actor of the character being controlled by the palyer

so i have to call SetOwner on Begin Play

of such child actor

am i wrong?

[graceful cave]

child actors cant actually replicate

as far as i know they dont get a net ID to associate with the server so only the class can be replicated but not the object

[covert gorge]

well, i am not sure what do you mean

but it worked perfectly

thank you so much! ❤

now i am able to call a server RPC from that actor

that is a child actor of a character being controlled by the player

[graceful cave]

really? like from a child actor component?

[covert gorge]

yes!

[graceful cave]

i wonder if they changed that in a recent engine version because that didnt used to work

[covert gorge]

i don't know, but that is exactly what i was looking for

thank you!

[winged badger]

@somber glade now expand the ChildComp in locals down to UObject

and look at its flags

[somber glade]

Yes, it's the netsmoother

@winged badger

[winged badger]

expand all the way

into UObjectBase

[somber glade]

@winged badger The StatID seems to be null

I have no idea what that it is, but it is null

[winged badger]

no, component is good

its a hook for the profiler

[somber glade]

so if the component is good, why is it throwing an exception?

[winged badger]

problem is, its 2 steps into the engine code

is that a source build?

anyways, put a breakpoint to that line

and then step into the UpdateOverlaps with F11

(don't put a breakpoint before you're ready to hit whatever button/command starts the travel)

[somber glade]

It's not a source build no

it's a plugin

VRExpansion Plugin

engine is stock 4.22.3

[winged badger]

ah, that explains why its not showing external code

also, check for WorldPrivate on that component

and find the name of PersistantWorld from that entry

[somber glade]

Okay one moment. I sort of lost my debug path and I need to get back to it. Also trying a quick fix to see if it's really the netsmoother.

[twin juniper]

I hvae a question

how many players can UE4 handle?

[somber glade]

there was a thought that it might be checking overlap stuff on children that weren't primitivecomponents. So I updated the check to only do it on those. It worked the first time. But when I restarted host and client and tried again, it crashed. So I'm going to debug again

I'm not getting a crash in a different spot @winged badger

[twin juniper]

hello

[somber glade]

I think I saw people mention that your player limit is machine/performance limited

[bitter oriole]

Well yeah

[somber glade]

I don't think there is any hard number like 100 or 1000

[twin juniper]

for the players that ue4 can handle?

cuz I saw the maximum was 64 and wanted to see if that was just for testing

[somber glade]

I mean..fortnite is 100 isn't it?

[twin juniper]

oh

do you need a dedicated server?

if not, that means that it's p2p

[bitter oriole]

@somber glade 100 is basically the engine's limit that you can reach with immense effort

Obviously anything more than 5-6 will need a dedicated server

[twin juniper]

then do I need to do scripting and replicating without

the engine's help?

I mean the built in service

[meager spade]

engine has built in support for ListenServer and Dedicated server

[real yacht]

how to obtain the port that the current server instance is bound to?

[twin juniper]

okay

so this is not peer to peer right?

[bitter oriole]

Real peer to peer doesn't exist in UE4

[meager spade]

UE4 works on a Server Authority system, Server is either a Client acting as a server (Listen Server) or a dedicated server

[bitter oriole]

"Listen server" means one of the players, while playing, also acts as server

[twin juniper]

so it works with a project not editing the engine script

is it?

[bitter oriole]

If you mean engine code, yes

You don't need to change it

[twin juniper]

okay

then I just need to have one project

acting as a server

[meager spade]

no

[bitter oriole]

No

[twin juniper]

oh

[bitter oriole]

You('ll just have the game

[meager spade]

UE4 runs headless server

[bitter oriole]

And some players will start the game as "listen server"

Which work out the same for them

Other players will connect to them

[meager spade]

if its dedicated ^^

[twin juniper]

then what do I do with the script I have for the server

I have my own logics I have that I need to attach

[bitter oriole]

What's "script" ?

UE4 has Blueprint or C++ code

[real yacht]

which script?

[twin juniper]

the server

because I have to export it

and if it runs on one server

I need to edit that

[bitter oriole]

Using the listen server setup, there is no physical server

One player will be the server

[meager spade]

http://cedric-neukirchen.net/2017/02/14/multiplayer-network-compendium/ is worth checking out @twin juniper

[bitter oriole]

So there is nothing to export other than the game

[twin juniper]

ty

can I know how to attach "init_unreal.py" to a project?

[bitter oriole]

What's init_unreal.py ?

There is no Python in UE4

[twin juniper]

like in the engine

okay then can you do it with cpp?

[bitter oriole]

We can't explain to you how to use things that you made yourself

We also don't know what you're asking here

[real yacht]

how to obtain the port that the current server instance is bound to? 😃

[meager spade]

@real yacht i was actually lookling into that

[twin juniper]

can you make a cpp file that runs when the game is executed?

[real yacht]

i'm asking because of gamelift

[bitter oriole]

If you're using Gamelift, ask the gamelift support or read their doc

I guess this is explained somewhere ?

[real yacht]

well that doesn't have nothing with gamelift actually

i just need to initialize gamelift with some port 7777

or some other port that instance is bound to

[meager spade]

err

GetWorld()->URL.Port

[real yacht]

so with ue

[meager spade]

may get your port

try it

[bitter oriole]

@twin juniper There is no such thing as "running a cpp file" - that's not possible anywhere. A C++ file is compiled into the game executable, and then the code inside the file runs whenever you call the methods in it

You should explain what you actually want to do

[real yacht]

@meager spade thnx

[bitter oriole]

Asking inaccurate questions that make little sense makes it hard to answer - say what you actually want to happen

"I want to create a multiplayer game" or "I need to work with 30 players" etc

[twin juniper]

so I want to make this multiplayer game

with server and client game system

[real yacht]

@twin juniper do you have game programming experience?

[twin juniper]

umm

[bitter oriole]

Let's epxlain the goal first

[twin juniper]

I learned a couple languages

[bitter oriole]

What do you want to do exactly

"Multiplayer game" ok

[twin juniper]

with a dedicated server

[bitter oriole]

You say you want a client and server - is there any reason you want to have a dedicated server software ?

Because it's much more complicated

[twin juniper]

I am trying to send info back and forth

from the game to the server

that takes what it received

and checks everything and sends back info back

[bitter oriole]

Okay, so a RPC

In UE4 parlance

[twin juniper]

yeeah

i think so

[bitter oriole]

So what is your problem now ?

[twin juniper]

well, I was just trying to send arrays

in a way hackers can't understand what it's sending

[bitter oriole]

That's not possible really

[twin juniper]

so I send an array

[bitter oriole]

Every platform is open to hackers

[twin juniper]

for example, the first element of the array is what kind of data it is

in random numbers

and all of them stand for different types of data

[real yacht]

?

[twin juniper]

and the server understands that and does what it received

[bitter oriole]

That's terrible security

Not even security really

Defending against hackers doesn't really work like that

[twin juniper]

how should I do it?

because it is always decodable and it can be modified

btw I was trying to send this with UDP

[fleet raven]

what you should be doing is completely forget about that

there is no point worrying about security if you don't have an actual product where it matters

[bitter oriole]

@stray linden It's basically entire impossible on PC to prevent the client from intercepting the data

Well it's impossible generally, on every platform

Just even easier on PC

[lusty heath]

Hey my friends I need some help.

I've been trying to do a VR multiplayer project for a while. A lot of things already working but not others and I can't understand why. For example, the client basically can see almost everything the server does, the server's hands and the server's interaction with some objects. But the server doesn't see anything from the client (can't even see the hands, what is very odd since server can successfully replicate the same hands to the client).

The interactions with objects already have authority switch (multicast and run on server) , but again, just clients can see what server does, server can't see anything.

[twin juniper]

i have no idea how vr in ue4 works but i do know the client must tell the server what they are doing, and then the server must broadcast what that client is doing to all other clients in order for "multiplayer" to work

[lusty heath]

so it isn't just a matter of 'running on server' if authority is remote?

like...

[bitter oriole]

@lusty heath To be clear if that wasn't the case, replication is one way

Client-to-server communications can only happen through RPC

[twin juniper]

@lusty heath check this out

little more streamlined, you put all logic in pressed thing and it runs on server and clients all the same

if you wanna nit pick logic in pressed thing then just do auth/remote in there too

also!!! unless you are absolutely sure! never use reliable rpc! reliable rpc is SUPER expensive.

also if not clear, SendPressedThing is where the server can say "you cant grab this!" and stops broadcast then and there

[lusty heath]

@bitter oriole @twin juniper ahh, I see. I'll try it now, may thanks =}

many*

[somber glade]

is there a function that gets called after server travel when you don't use seamless?

[thin stratus]

Not really as that is handled like a fresh connection

ServerTravel should also always be seamless

Steam for example wouldn't even allow traveling without that

[gloomy sedge]

Hey Cedric, im reading up on your Steam Integration, and friends widgets. Has the plugin changed since your video? because i cannot seem to get the friend steam game display name any more

[thin stratus]

Not sure tbh

[somber glade]

Well..I can't track down what's causing seamless to crash for me.

so until I can, I can't use seamless

@thin stratus Debug won't give me anything usable so I can't figure out what is causing the exception

[gloomy sedge]

Not too worry, im sure i can find the right function sooner of later, I can find the Get App Id for the friend, but unsure how to retrieve the name from it

[thin stratus]

If it crashes while Vs is attached it should give you a break point, a call stack and even an error

[somber glade]

Yes it is has...

[thin stratus]

Then fix that?

[thin stratus]

it's trying to clean up an actor

[somber glade]

yes

[thin stratus]

Check which one

[somber glade]

I can't

it won't tell me

[thin stratus]

Just go back in the call stack and check the local/auto values

[somber glade]

I'll check that and see if it gives anything.

between 3 people we've been looking at this for 4 hours..it just keeps saying source isn't available but symbols are loaded

@thin stratus going back up the call stack locals/autos are empty for all

[thin stratus]

You seem to look at the crash after it happened or?

This is not a live breakpoint that happened

[somber glade]

No this is the crash point

[thin stratus]

Why don't you attach VS to your running game

[somber glade]

I'm running the game from VS in debug game

this is the only one that has any variables

[winged badger]

no engine debug symbols

[somber glade]

I have engine debug symbols

[winged badger]

you have editor debug symbols

[somber glade]

ah.

how do I get the engine ones?

[winged badger]

i had to cook from a source built editor

[fleet raven]

huh, so actors that drop out of relevancy for a short time actually get destroyed on the client?

[winged badger]

that is the client callstack, if you're inferring from it

[somber glade]

yes, it only crashes on the client.

the host never crashes.

the client crashes about 90% of the time.

well 95

There is basically nothing in the lobby. There is a static mesh floor, 2 pawns, and an actor that holds the lobby widget.

I did cast to the lobby actor and blank the widget before seamless travel

and that did help

I mean, the client crashed later

it still crashed, but it got further.

The target level that we're going to has a single static mesh floor

and 4 player starts.

the transition level has nothing.

There are basically no actors to work with here.

The only other thing I could try would be to delete the lobby actor and just bind a key on the host to launch the level

I've never built from source before. Will I be able to open this project and work with it directly in a built version?

[winged badger]

yes, but this all seems over the top

[somber glade]

What else can I do though?

I've stripped the thing down to the bare bones.

i tried depossessing and destroying the pawn to make sure that wasn't causing an issue

I reparented my instance and removed all my vivox code

that didn't help

It's been 3 days straight trying to figure out what the issue is. Tracking down little bugs and things here and there, but this one persists.

This is the closest I've gotten, but without this debug info, there is no way to see what the actual issue is

So i'm going to build a version with the only other thing I can do. I've deleted the lobby menu in the lobby and bound a key for the host to call start game without a menu

At this point there are 4 actors in the game, a floor in the lobby a floor in the target and 2 pawns. They're all essential

..... it looks like it was the lobby holder.

it's the most basic of actors.

an actor with a widget, and it's replicated, and that's it.

nope.

it was just teasing me.

2 successes in a row

then a crash

[timber garnet]

How do you implement your own online subystem? The documentation bascially only talks about Steam. For instance if I have 4 dedicated servers running on Digital Ocean and each server can host two players, how do i overrideFind Sessions so that I can populate it with server IP addresses? The subsystem design pattern is awesome,but there is no info on how to write your own subystem and tap into the events/apis

I literally have all the matchmaking done, IP addresses,etc. Now I just need to somehow create sessions from that data so Join Session will work.

At this point the only thing I can think to do is override all of those built-in subsystem classes with my own implementation

[somber glade]

I managed to crash this in editor doing seamless. So I have some more information..except everything is just null there isn't a single name in here to work with

[rain sandal]

Wondering if Epic will be allow us to use Easy Anti-cheat as part of online services. I heard they bought the company, but I've not heard anything about wider implications that would be relevant to us.

[crimson fiber]

weird... so you can't call server RPC on actor from actor's owner client-side?

[meager spade]

eh?

thats the idea of Server rpc's

clients can call them

[crimson fiber]

apparently Player Controller client can't call server RPC on Character with AI controller

I suppose because Character isn't locally controlled, so RPC is dropped

server RPC from owner works with actors but not with characters

[night jay]

Hey guys, I'm suffering from a weird problem recently

I believe since 4.22 idk

In PIE, the clients take a long time to initialize

Server is fine

But clients can take minutes before I can move them around. Their pawn does spawn, I believe the player controller or playerstate is being stalled somehow

[fluid flower]

Perhaps saturation due to high frame rate?

What fps are you running at

[crimson fiber]

oh I missed replication so much! more ridiculous nodes to the god of nodes

[night jay]

I'm around 30

[strange igloo]

hello

i have big problems concerning multiplayers in my project

i will give you a video that explain you my problems

but it is in french

https://www.youtube.com/watch?v=Sq0vnOz1x-w

[wary willow]

Alright, ran into a strange issue which probably doesn't happen too often and may be by design?

MP Game.

Pawn A moves. It's a vehicle.
Pawn B is a Pawn, with camera. I am going to use this as a "sensor".

I attach Pawn B to Pawn A successfully (AttachToComponent, SnapTo Loc/Rot).

However, for the life of me, I can't get Pawn B (The Sensor Pawn)'s camera to rotate based off Pawn A's component that is definitely rotating (can see the print string rotation of Pawn A's component). The actor itself is definitely rotating (again, Print String shows both clients rotating).

**I ended up using what I think is a hack, but maybe someone can shed some light on this. **

By using SetControlRotation and ticking UsePawnControlRotation on the camera I was able to get the desired effect. Right now this is on everyone's favorite Event: Event Tick

Normally, rotating the Camera isn't an issue since you usually are using Input to rotate it. Or if you don't want to rotate the camera, you have it fixed. And if you want different views, you blend between them. So maybe this isn't really a MP issue, just how cameras work by design, especially in pawns.

[steel cove]

In my experience attaching actors to each other never replicates correctly

To be sure I simply use a replicated property to store which Actor something has to be attached to and perform/remove the attachment using the property's OnRep function on clients to match the server

[wary willow]

Oh, I've actually never had issues attaching regular actors to each other in MP. I think it's simply a "Camera" issue with the very niche use-case I am doing.

[harsh lintel]

is there any difference between using GetPlayerCharacter node and using GetControlledPawn node in a multiplayer scenario?

[wary willow]

yup

but it depends on where/how you use GetPlayerCharacter

http://cedric-neukirchen.net/2017/02/14/multiplayer-network-compendium/ Page 40

[harsh lintel]

makes sense thanks, I'll have to change a lot of things lol

[winged badger]

@harsh lintel a good rule is: if you can use GetControllerPawn

never use GetPlayerCharacter

infact, wouldn't be bad if you designed your code never to have to use GetPlayerCharacter at all

especially if its a learning project and you don't have a deadline looming over your head 😄

[harsh lintel]

ill keep that in midn

mind

to fix this in a custom blueprint I'm casting to a custom character class and using GetController() node but that doesn't seem to have player controller functions...

do I need to cast the return from GetController() to player controller?

[harsh lintel]

it works with casting so that's solved

im trying to change max walk speed on the client but it's failing to cast the controlled pawn to a character class

tried replicating movement component, replicating controller, calling the speed change function through a client rpc, calling the previous client rpc through On Possess event with no luck

[indigo robin]

is there a properly synced (latency compensated) server simtime available from the client ?

by latecy compensated i mean like it increases on the client but is periodically corrected like ntp

and i dont mean just "make a rpc to get it"

[winged badger]

the gamestate replicates the server workd time by default

consensus its extremely unreliable

but sending a Server RPC to get it, and sending a Client RPC reply with the both carrying client timestamp at the time of query, and reply also server time

lets you calculate delta within a reasonable margin

then you just cache it and add it to client world time

[indigo robin]

i guess that only works if you assume roundtrip latency is 2x one-sided latency

and there was no cpu delay processing the rpc

clienttime in rpc -> server sends back server time when it got the rpc (it cant do any compensation here cuz its not synced with the client), client gets back server time from when the server got rpc and client time of the request, it subtracts (currentTime-requestTime)/2 from it

the time will be slightly off depending on the delays in processing the rpc on the server and client though

is it possible for me to change the logic of ReplicatedWorldTimeSeconds and GetServerWorldTimeSeconds ?

why have 2 different time sync going on at the same time

[low pond]

With RPCs and replicated properties how does ordering work between them?

[indigo robin]

theres no ordering between them

properties are replicated whenever they can be, if theyve changed

[chrome bay]

The point of GetServerWorldTimeSeconds() is to return the estimated current time on the Server, accommodating for latency as best as possible.

But in answer to your question no, there's no accurate version and probably never will be. You can't really ever have a perfectly synced time between two different PC's.

[indigo robin]

GetServerWorldTimeSeconds doesnt accomodate for latency, it returns lagged-time on clients

[twin juniper]

Good day. I need to find the index of my own player controller. Does anybody know how to find it? Thanks for attention.

[chrome bay]

@indigo robin look at OnRep_ReplicatedWorldTimeSeconds()

And the tooltip for GetServerWorldTimeSeconds(), which states /** Returns the simulated TimeSeconds on the server, will be synchronized on client and server */

[indigo robin]

yes its synchronized

but its behind on the client by that client's latency

which is fine, sometimes you want that

[chrome bay]

Oh right yeah, my bad. I was using it to sync weapon firing times but I do the lag bit myself

[indigo robin]

you can do this to get a lot closer to the server's actual time https://medium.com/@invicticide/accurately-syncing-unreals-network-clock-87a3f9262594

[chrome bay]

Just a basic ping/pong would do it

[indigo robin]

but thats really something that should be done with the actual raw packets

not RPC

isnt RPC stuff checked in the game thread so it can be behind by an entire frametime ?

[chrome bay]

I guess it depends how accurate you really need it to be, and where you're accessing it from. If you're getting the time on the game thread anyway it wouldn't matter

[indigo robin]

ideally it happens internally on net connection establishment and then ocassionaly packets would also have some ping/pong for sync reasons

[chrome bay]

Yeah.. I guess the other problem is different frame deltas as well

[indigo robin]

in that article you actually probably dont want the ServerRPC to be reliable either

as reliable resends would copy the original client timestamp in them

while you want latest timestamp in them

[chrome bay]

Unreliable is faster too

As in, they arrive quicker usually

[winged badger]

the proposition there was that you do it once

cache the time delta and call it a day

[indigo robin]

you cant rely on client CPUs to keep track of time exactly like the server does

it will drift

[winged badger]

only by a variance in DeltaTime

[indigo robin]

i would probably want to do this every second, and then use the average (with outliers removed) delta

of last 5 times

[winged badger]

yeah, i would do it every 10 or so

and just plain discard any samples that have significant deviation

but worrying about the time to process an RPC there is pointless imo

since any network solution will have an error greater then that

[indigo robin]

i just want the most accurate timestamps for my client's requests to the server

[winged badger]

the gamestate's default replicated one is just plain terrible

i mean, its fine for syncing a 2 hand clock on the wall

[chrome bay]

I guess that's what it's meant for really, if you know you need a super-accurate clock you probably know how to implement one

[glad sedge]

do we still have to do the whole 'Server_PossessNewAIController_Implementation' thing?

specifically the _Implementation addition

[chrome bay]

yes

and _Validate

For Server/WithValidation RPC's anyway

[glad sedge]

ok cool just checkin

[chrome bay]

just be sure when you call said function you call the non-implementation version

caught myself out with that plenty of times...

[winged badger]

so nice its consistent, because if you call something other then _Implementation from an overriden BPNativeEvent, you crash

[shrewd frigate]

Is voice chat possible with gamelift? Can't seem to find it on their docs.

[thin stratus]

Doubt that GameLift has that

As this is not really a Feature that GameLift is made for

[indigo robin]

@chrome bay actually it seems a Reliable RPC writes to the sendbuffer immediately while Unreliable could wait

[chrome bay]

I got that from an engineer at Epic, but take it with a pinch of salt. According to him unreliable should get to the target "faster" - but probably depends on saturation etc.

[indigo robin]

also is there a way to specify that a replicated property should only ever be sent alongside another one

[chrome bay]

It probably becomes an issue when reliable ones aren't getting through and they need to be resent

yeah put them in a struct

[indigo robin]

aka if one updates i want to make sure the other one's value is correct as well

arent structs replicated memberwise ?

[chrome bay]

Well.. yes and no. If you implement a custom NetSerialize function for a USTRUCT, it will always use that function for network use and the engine won't generate an FRepLayout

If not, it's based on property changes

I assumed to meant you wanted changes made to arrive at the same time

[indigo robin]

yes

[chrome bay]

ie.. float A and float B need to come down together

if they're in a struct, both values will be up-to-date when you use them in game code

[indigo robin]

but i should still write a NetSerialize for the struct so that it doesnt waste time sending over FNames for the member names ?

[chrome bay]

It won't do that anyway

Oh unless you have an actual FName being replicated of course

[indigo robin]

how does it reference replicated vars if not by their fname