#multiplayer | Unreal Source | Page 461

twin juniper May 9, 2019, 5:22 PM

#

Yes

#

If i understand correctly yes

thin stratus May 9, 2019, 5:24 PM

#

If yes then:

Server:

Whenever you want to actively "host", you have to call the OpenLevel node and pass listen as an option in it.
That's basically all, that will move the Server (ListenServer) to a new Map and it will "listen" on port 7777 by default.

Client:

Have some sort of TextBox in UMG that can take an IP-Address.
When a button or so is clicked (e.g. Join IP) you take what is in the IP-Address TextBox and use the node ExecuteConsoleCommand.
-- The command you want to execute is "open" to which you need to append the IP-Address open 127.0.0.1

#

That's basically all

#

Just requires 2 things: Port Forwarding and sharing the public ip of the server.

#

But that's enough for simple testing between two devs

#

(if you want to avoid setting up Steam and Sessions for now)

bitter oriole May 9, 2019, 5:25 PM

#

TBH I feel like Steam and sessions is easier.

thin stratus May 9, 2019, 5:25 PM

#

Technically yes, but if it for whatever reason doesn't find the Sessions cause of 480 id, they have 0 idea how to debug that

#

Cause as soon as Sessions don't work, it's basically a shit show

bitter oriole May 9, 2019, 5:26 PM

#

Sure

thin stratus May 9, 2019, 5:26 PM

#

You can try it of course

bitter oriole May 9, 2019, 5:26 PM

#

NAT punch though

twin juniper May 9, 2019, 5:26 PM

#

This is extremely informative. I will try this now wish me luck guys.

#

Wait

#

one tihng

#

Okay so how will ido the player spawns?

#

how will they work?

thin stratus May 9, 2019, 5:27 PM

#

That has nothing to do with the connection process

twin juniper May 9, 2019, 5:27 PM

#

I understand that this opens a level but where will the player that joins the level spawn?

thin stratus May 9, 2019, 5:27 PM

#

Whereever you set it up

twin juniper May 9, 2019, 5:28 PM

#

Player start?

thin stratus May 9, 2019, 5:28 PM

#

Well you have tested the game with 2 players in the editor already or?

twin juniper May 9, 2019, 5:28 PM

#

no lol

thin stratus May 9, 2019, 5:28 PM

#

Then do that first

#

Next to the PLAY button at the top

#

There is drop down arrow

#

At the bottom of that menu you can set the playercount to 2

#

That will automatically create a ListenServer with joined client (don't do that in the MainMenu!)

#

Then you can see where they would spawn

twin juniper May 9, 2019, 5:29 PM

#

this was useful

#

I will have the open level and listen function on the gamemode or playercontroller or gamecharacter blueprint?

#

or does it even matter?

thin stratus May 9, 2019, 5:32 PM

#

Sessions require these steps:

Enable the Steam Plugin for your Project (in the Plugins section or via uplugin file editing).
-- Edit the DefaultEngine.ini file according to whatever tutorial you find online (don't have the changes in my head).

Server:

Use the "CreateSession" node which requires some parameters
Once the CreateSession node returns successful (second exec pin on the node) you call OpenLevel with the listen option again (same as in the other setup).

Client:

Use the "FindSessions" node. This will return 0 to x Sessions depending on how many hosts are in your near range (Steam basis this on regions with the 480 test id)
Once you found a session you can either blindly join it via the "JoinSession" node, or iterate over the array of Sessions and display them in a UMG list.
-- If you display them you'd create a new Widget (server entry) per result and save the result in it. When clickign the widget you'd join the result again, but this is more complex and advanced of course.
So just taking the return array and doing "if length == 1 -> Join Element 0" should be enough

twin juniper May 9, 2019, 5:33 PM

#

Are these two different methods or is this the same mehod?

thin stratus May 9, 2019, 5:33 PM

#

@twin juniper Technically it doesn't matter.

#

My connection process is in the GameInstance

#

That is the Session method

twin juniper May 9, 2019, 5:33 PM

#

Okay cool

#

I will try the first one seems easier

thin stratus May 9, 2019, 5:33 PM

#

It doesn't require opening ports, but is more complex and for beginners easier to have errors

#

Please be aware that if the host fails to open the ports in their router and firewall settings, the first method will most likely fail.
So make sure one of you two has that figured out

#

The default server port is 7777

#

That's all I can give you for now. Gotta be busy a bit now, cheers

twin juniper May 9, 2019, 5:35 PM

#

Okay thank you so much brother.

#

Oh shit

#

The listen thing

#

do i put "listen" in the options tab of the open level thing?

twin juniper May 9, 2019, 5:54 PM

#

@twin juniper
You're using bps right?

thin stratus May 9, 2019, 5:55 PM

#

Yes @twin juniper

twin juniper May 9, 2019, 5:59 PM

#

Can anyone tell me how to use LineTraceByChannel to damage another player? I tried so many times and I can't get it to work

#

Okay so i think it's working but a problem is only the actual characters update on the server. All physics simulating objects are all client sided. So one one client i can have moved a physics object like 100m away but on the other clients screen the object is still in the same place. Any ideas?

#

Nevermind now for some reason it works

#

it seems like

#

Okay in the ue4 editor it works

#

but if i launch it from the WindowsNoEditor packaged version it doesn't

#

they are desynced

#

any ideas?

thin stratus May 9, 2019, 6:15 PM

#

Physics Simulation is really nothing you want to network

#

If at all, the Server would simulate it and just send the location updates

#

Otherwise it will go async

#

Physics are not deterministic

#

Two times the same throw can end up on different locations on different clients

twin juniper May 9, 2019, 6:16 PM

#

How do i make the server simulate physics and not client?

thin stratus May 9, 2019, 6:16 PM

#

You could set the boolean on BeginPlay and filter with SwitchHasAuthority

solar stirrup May 9, 2019, 6:32 PM

#

Do I need to implement NetSerialize() for an FFastArraySerializerItem or is it optional?

twin juniper May 9, 2019, 6:41 PM

#

Okay so the characters seem like they are lagging on the server?

#

they seem like they are moving at 10 fps

#

How can i change this?

#

And what is responsible for this?

thin stratus May 9, 2019, 6:43 PM

#

Are the lagging back and forth?

#

Are you modifying the movement speed runtime somewhere?

#

If yes, you have to do this properly via a RepNotify variable

#

Also it seems like you are having problems with the basics, so you should really read over my compendium (pinned to this channel) And just try around in a test project a bit.

bitter oriole May 9, 2019, 6:44 PM

#

Check the engine setting that lowers performance in background, first. That causes extreme lag when a window isn't focused.

thin stratus May 9, 2019, 6:44 PM

#

That too, never had such issues so I never think about actual fps problems >.>

past rain May 9, 2019, 6:47 PM

#

On dedicated servers, my clients are moving super smooth. Once I switch to server-model, where a player is the server, then the client has jittery movement. I'm failing to understand how client can have smooth movement on a dedicated server, but once a player is a host the client jitters

#

Does anyone have any clue?

thin stratus May 9, 2019, 6:48 PM

#

Does the client jitter on the server view?

#

Or locally?

past rain May 9, 2019, 6:49 PM

#

Only locally

grizzled stirrup May 9, 2019, 7:04 PM

#

@past rain It's a BIG issue and seemingly no fix without downloading the source version of the engine and modifying some parts of the CMC

twin juniper May 9, 2019, 7:04 PM

#

I'm not really lagging. The characters move exactly where they are supposed to but they do it at a very low refresh rate

bitter oriole May 9, 2019, 7:04 PM

#

Show the framerate

grizzled stirrup May 9, 2019, 7:04 PM

#

I think you are also having the same issue as Sendach

#

Basically the listen server only updates client animation frames on net updates

#

Not sure why it defaults to this behavior but it does

#

It's not that way on dedicated

#

Other clients should see each other smooth and should see the sever smooth AFAIK

#

Try with 3 players or with the dedicated server checkbox ticked

past rain May 9, 2019, 7:05 PM

#

When you say animation frames, do you mean actual animations? because I have no animations

grizzled stirrup May 9, 2019, 7:05 PM

#

Yeah the animations getting ticked as well as an interpolation in movement, there's 2 problems with it

#

Here's a thread with some info: https://www.reddit.com/r/unrealengine/comments/a0n455/listen_server_host_sees_clients_jittering_fix/

r/unrealengine - Listen Server host sees clients jittering fix

7 votes and 3 comments so far on Reddit

#

It seems to only affect listen servers which is a shame

past rain May 9, 2019, 7:06 PM

#

The thread you posted suggests that the listen server will see all clients jitter

#

correct?

grizzled stirrup May 9, 2019, 7:06 PM

#

Yep

past rain May 9, 2019, 7:07 PM

#

Thats not the case with me

#

The listen servers see the clients move smoothly

#

Only the clients perspective see themself jitter

grizzled stirrup May 9, 2019, 7:07 PM

#

Ah then it's a problem with your netcode

past rain May 9, 2019, 7:07 PM

#

But not on dedicated server

grizzled stirrup May 9, 2019, 7:07 PM

#

Hmmm

#

@twin juniper there's more info in general about the listen server jitter here if interested: https://forums.unrealengine.com/unreal-engine/feedback-for-epic/1346282-impossible-use-ue4-for-a-coop-or-mp-listen-server-game-due-the-unfixed-network-errors-since-4-years

Unreal Engine Forums

Take me about one week to find out the problem that I see the clients in my game with teleporting/lag/jitter error. No one know or have clue and there is no docs

past rain May 9, 2019, 7:07 PM

#

Yeah but I cant wrap my head around what could be causing this on a listen server but not dedicated servers

grizzled stirrup May 9, 2019, 7:08 PM

#

How many fps are you getting in general?

#

Probably not the issue but there have been a few weird issues I've encountered with high fps on listen servers lately

past rain May 9, 2019, 7:09 PM

#

how can I check

grizzled stirrup May 9, 2019, 7:09 PM

#

stat fps

past rain May 9, 2019, 7:12 PM

#

https://gyazo.com/bbebc09b920d4214373c1b31b7a1e525

Gyazo

#

you mean this?

bitter oriole May 9, 2019, 7:13 PM

#

stat fps in console

#

Check framerate when the lag appears

past rain May 9, 2019, 7:15 PM

#

Both listen server and client

#

are at a solid 70 fps

bitter oriole May 9, 2019, 7:19 PM

#

That's one less thing to worry about

solar stirrup May 9, 2019, 7:22 PM

#

Do I need to implement NetSerialize() for an FFastArraySerializerItem or is it optional?

twin juniper May 9, 2019, 7:31 PM

#

lol guys

#

my friend downloaded cheat engine and speedhacked like he was usain bolt

#

how can i prevent this lol?

thin stratus May 9, 2019, 7:31 PM

#

By preventing whatever they changed

#

CheatEngine should only allow you to change local stuff

twin juniper May 9, 2019, 7:32 PM

#

the only thing he changed was speed

thin stratus May 9, 2019, 7:32 PM

#

So if you don't allow the client to set the Speed on the Server, they shouldn't be able to do that

twin juniper May 9, 2019, 7:32 PM

#

how can i do that ?

thin stratus May 9, 2019, 7:32 PM

#

They will get correct instantly

#

Well idk how they are setting speed

#

But if only the local MaxWalkSpeed was changed, then it shouldn't be possible to cheat

#

Cause the CharacterMovementComponent will reset you

twin juniper May 9, 2019, 7:33 PM

#

okay thats weird?

#

yes i use character movement

#

notthing else

thin stratus May 9, 2019, 7:33 PM

#

Try it yourself, change the speed locally and walk around

#

You'll constantly get teleported to where the server moved

#

Cause the Client performs the move and sends the Server the location they ended up

#

Then the server does the same move and compares

#

If they are different the server will override the client

twin juniper May 9, 2019, 7:34 PM

#

hmm oooh i forgot to mention and i actually forgot the outcome completely

#

what happened was

thin stratus May 9, 2019, 7:34 PM

#

Was your friend the host?

#

Cause you can't stop cheats on ListenServers

#

The hosting Player has authority

#

You should also not develop a game that requires players to not cheat

#

Cause that requires A LOT of knowledge

#

And in the end even money

#

Cause you need to host DedicatedServers away from the client

twin juniper May 9, 2019, 7:35 PM

#

On his screen he was speed hacking like crazy but on my screen he was just staying in the same place and even when he stopped he was completely desynced and he couldn't move at all on my screen but on his screen he was moving like normal?

thin stratus May 9, 2019, 7:35 PM

#

So whatever game you are working on, change the aspect that requires them to not cheat

#

Yeah well just don't care about it

#

Cheating can't be stopped in a listen Server setup anyway

#

And as just said, don't dev a game that needs players to not cheat

#

It's too big for a beginner

twin juniper May 9, 2019, 7:36 PM

#

Understanable

thin stratus May 9, 2019, 7:37 PM

#

Just sell the game for a flat price if it comes out

#

And if they cheat -> don't care

#

Don't make it competitive

#

And it should be fine

#

(so don't make Overwatch, PUBG, Apex, LoL, or any MMO)

twin juniper May 9, 2019, 7:38 PM

#

I honestly don't care about cheating. But if it's a public match then i don't want them to cheat to ruin the experience. But if it's private it's fine. By the way is it possible to make a server list which displays all listen servers that are port forwarded?

thin stratus May 9, 2019, 7:39 PM

#

ServerLists are done via Sessions. That is done by using Subsystems such as Steam.

#

Steam does a so called "NAT PunchThrough" which works around the port forwarding.

#

So if you do have ServerLists, they usually don't need port forwarding

#

And as mentioned: Preventing cheating is difficult on a programming level (needs a lot of knowledge) and is pricy (servers have to be hosted by you away from players).
Plus it's (sorry to say that) highly unlikely that you produce a game with that knowledge that will have enough players to support such a server setup.

#

User ListenServers or share the DedicatedServer setup and stop caring about cheats

#

Don't make competitive games :P trust me here, i do this for 5 years already (with ue4 and multiplayer) and for a living and I can't recommend this at all

grizzled stirrup May 9, 2019, 7:46 PM

#

Not to mention lag compensation and anticheat which are essentials for competitive games

#

But don't let all that dissuade you, there's plenty of room for fun multiplayer games that don't need competitive gameplay

#

co-op being a major one

thin stratus May 9, 2019, 7:48 PM

#

You can have competitive gameplay, just not based on a skill elo system or so

#

It's totally fine to havea game between a few friends where you hit each others face in

#

Give the host kick rights so they can kick cheaters and it's fine

#

Just don't make something where a "ranked" mode exists

grizzled stirrup May 9, 2019, 7:48 PM

#

Yep exactly

#

Just wish they fixed this for listen servers: https://issues.unrealengine.com/issue/UE-32005

#

It really makes the game feel like it's lagging when in fact it's not

twin juniper May 9, 2019, 7:49 PM

#

Okay. But does anyone know why the person who uses speedhack get desynced? I just tried it out locally and the player is just frozen if he speedhacks

#

even if he turns it off

#

on his own screen he can move

#

but on the other players screen who is not hacking he is just frozen in time

#

any explanation lol?

fleet raven May 9, 2019, 7:51 PM

#

listen server characters also only tick the animation when they receive an update from the client

#

that's probably the most visible thing

grizzled stirrup May 9, 2019, 7:51 PM

#

Yeah it's both that plus not interpolated

fleet raven May 9, 2019, 7:51 PM

#

the thing is

grizzled stirrup May 9, 2019, 7:51 PM

#

So it looks extra jittery

fleet raven May 9, 2019, 7:51 PM

#

the animation on the server side drives things such as weapon positions

#

so if it was interpolating to look nice to the host it would be wrong

grizzled stirrup May 9, 2019, 7:51 PM

#

In my case that is completely fine

#

Is there an easy way to just let the client interpolate fully smoothly?

fleet raven May 9, 2019, 7:52 PM

#

I'm wondering how to solve that in my case

grizzled stirrup May 9, 2019, 7:52 PM

#

Also in the case of dedicated servers, it isn't an issue

#

Which is the same problem (weapon position on the server)

fleet raven May 9, 2019, 7:52 PM

#

well a dedicated server doesn't need to interpolate anything

grizzled stirrup May 9, 2019, 7:52 PM

#

Ah yeah sorry this issue is for the listen server viewing clients right?

fleet raven May 9, 2019, 7:52 PM

#

as it has no visuals

grizzled stirrup May 9, 2019, 7:52 PM

#

not clients viewing other clients or server

fleet raven May 9, 2019, 7:53 PM

#

yes

#

the movement can only update when it receives a move from the client with a new timestamp

grizzled stirrup May 9, 2019, 7:53 PM

#

Using a source build I managed to get it fixed using these steps: https://www.reddit.com/r/unrealengine/comments/a0n455/listen_server_host_sees_clients_jittering_fix/

r/unrealengine - Listen Server host sees clients jittering fix

6 votes and 3 comments so far on Reddit

#

But I'd really like to do it without a source build

twin juniper May 9, 2019, 7:54 PM

#

How can i add usernames to a listen server guys?

grizzled stirrup May 9, 2019, 7:54 PM

#

you can store the player name in the player state of each client and have it shown wherever needed

fleet raven May 9, 2019, 7:54 PM

#

I guess it could be "properly" fixed using some predict/reconcile logic on the server side but that's kinda br_oof

grizzled stirrup May 9, 2019, 7:55 PM

#

It really did seem to mainly be thebOnlyAllowAutonomouseTickPose line, but setting it in a child class in a binary build didn't seem to work for some reason :/

fleet raven May 9, 2019, 7:55 PM

#

old engines like torque solved this better by having the server sided game state separate from the visual game state of the listen server

#

what this change will do is make the animations tick every frame

grizzled stirrup May 9, 2019, 7:56 PM

#

That's what we want for the animation to not appear choppy though right?

fleet raven May 9, 2019, 7:56 PM

#

so if I did this my weapons would be positioned incorrectly

#

as it's no longer in sync with the client timestamp

grizzled stirrup May 9, 2019, 7:56 PM

#

I thought that it is fine as long as the weapon is attached to the mesh and not outside of the mesh component

#

Ah you are going pretty hardcore

#

I just need a smooth update

fleet raven May 9, 2019, 7:57 PM

#

I want the server to fire from and at exactly the same location the client saw

twin juniper May 9, 2019, 7:57 PM

#

I know this question is unrelated. But how do i open the default player controller? I am trying to do the thing were you store the username on player controller

grizzled stirrup May 9, 2019, 7:57 PM

#

Ah yeah that's very tricky, lagcomp stuff

fleet raven May 9, 2019, 7:57 PM

#

without giving the client authority over either

grizzled stirrup May 9, 2019, 7:58 PM

#

Speaking of movement, is it possible to cleanly replicate very fast speeds / LaunchCharacter() on the client without getting horrible jittering corrections?

fleet raven May 9, 2019, 7:58 PM

#

do the launch on the client side too, it adds it as a predicted action to the history

grizzled stirrup May 9, 2019, 7:58 PM

#

I have to try the implementation again but as soon as I was going over certain speeds, even calling launch on the client first and then on the server (with some latency) caused corrections

fleet raven May 9, 2019, 7:58 PM

#

hm

grizzled stirrup May 9, 2019, 7:59 PM

#

I may have just done it wrong but say at 200ms between the client and server, the client is in a greatly different position to the server even though they called the same thing

#

Maybe I can turn off the correction only while launching

#

but then when landing the client will snap....

fleet raven May 9, 2019, 7:59 PM

#

what triggered the launch?

grizzled stirrup May 9, 2019, 8:00 PM

#

A launch pad or a special rocket jump

#

It's fine for slower speeds

#

But fast speeds seem tricky

fleet raven May 9, 2019, 8:00 PM

#

yeah if these don't run in exactly the same movement tick on client and server, that'll be one br_oof

grizzled stirrup May 9, 2019, 8:00 PM

#

Yeah they do both get called, but latency 😄

fleet raven May 9, 2019, 8:01 PM

#

if your server is one tick later than the client it will send a correction which messes it all up

grizzled stirrup May 9, 2019, 8:01 PM

#

I'd love the client to be authoritive over his movement for my game and report his movement back to the server, but it seems the only way to do that smoothly is send MANY RPCs a second to the server which is a waste

#

Is the CMC sending many RPCs a second anyway?

#

Behind the scenes

fleet raven May 9, 2019, 8:01 PM

#

it sends multiple per frame

grizzled stirrup May 9, 2019, 8:01 PM

#

Per frame!!

#

DAmn

fleet raven May 9, 2019, 8:01 PM

#

ends up using something like 5kbps

grizzled stirrup May 9, 2019, 8:01 PM

#

Wow that's amazing

fleet raven May 9, 2019, 8:01 PM

#

it actually has a client authoritative mode, did you try that?

grizzled stirrup May 9, 2019, 8:02 PM

#

No I saw a reddit post mentioning it but not much else

#

I'll look into it now

#

That'd be a dream

#

All I need is the clients location and rotation sent to the server and other remote clients

#

Doesn't have to be too accurate

#

Just needs to look smooth

#

And be correction / lag free on the client

fleet raven May 9, 2019, 8:02 PM

#

it's not an option in my case so I don't know how it works, I just saw it mentioned somewhere

grizzled stirrup May 9, 2019, 8:03 PM

#

I'll give it a shot! Is the next best thing to send an FVector_NetQuantize via an RPC on tick?

#

I know that sounds insane

#

Or say 100 times a second

#

If it's not fast it looks really choppy on other clients

fleet raven May 9, 2019, 8:03 PM

#

doesn't seem insane to me, considering the movement already does this

grizzled stirrup May 9, 2019, 8:04 PM

#

Ok I really for some reason thought RPCs were only called infrequently like 10 times a second or so

#

Will try and dig into the CMC code too and try to understand it

#

My old implementation was in BP

fleet raven May 9, 2019, 8:04 PM

#

in fact it sends a shitload of stuff all the time

📎 unknown.png

grizzled stirrup May 9, 2019, 8:04 PM

#

Now I'm in C++ so there's more room to use better methods

#

Holy shit that's a lot of stuff

fleet raven May 9, 2019, 8:05 PM

#

PendingFlags is normally a uint8 but I changed it so I can put more flags in it

grizzled stirrup May 9, 2019, 8:05 PM

#

So if I was to send void ServerSendLoc(FVector_NetQuantize CurrentLoc);

#

That wouldn't even be so bad

#

On tick

#

Then the server would replicate that loc to other clients and they'd set the loc of that client locally

fleet raven May 9, 2019, 8:05 PM

#

keep in mind clients sometimes run at 200 fps because of course they do

#

so maybe limit it somehow

grizzled stirrup May 9, 2019, 8:05 PM

#

Yeah true, will cap it to maybe 60 a second

fleet raven May 9, 2019, 8:05 PM

#

to not send if the tick was < x ms

grizzled stirrup May 9, 2019, 8:05 PM

#

Just a timer on begin play

#

That's pretty eye opening, thank you for sharing!

#

Kind of explains why the bandwidth usage flys up when there are multiple characters just walking around haha

fleet raven May 9, 2019, 8:06 PM

#

you should definitely try the client auth mode first tho

grizzled stirrup May 9, 2019, 8:07 PM

#

Wish there was docs for it but I'm sure the code is commented

fleet raven May 9, 2019, 8:07 PM

#

it's kinda made for exactly that purpose

grizzled stirrup May 9, 2019, 8:07 PM

#

They likely do it in a much more clever way

#

Yeah!

#

Thanks, will look into it for sure

#

Between this and the bool that I can override OnPossessed, I think things will be very smooth!

fleet raven May 9, 2019, 8:07 PM

#

idk about it being commented

solar stirrup May 9, 2019, 8:18 PM

#

I have a FastArraySerializer array, which will be replicated between client and server

#

if the client modifies it, it won't do anything right? It'll just grab back the server's value?

twin juniper May 9, 2019, 8:19 PM

#

On a dedicated server will all physics object always be on the same place for all clients?

winged badger May 9, 2019, 8:20 PM

#

@solar stirrup client should not modify it

solar stirrup May 9, 2019, 8:20 PM

#

Let's say they're a bad meanie and they try to, what happens?

winged badger May 9, 2019, 8:20 PM

#

server will replicate items only when they are added, removed or marked dirty

#

it won't check if client pushed his out of sync

solar stirrup May 9, 2019, 8:21 PM

#

So cheaters would just fuck themselves over right?

winged badger May 9, 2019, 8:21 PM

#

also, not quite sure what happens if the item client removed gets modified on server

solar stirrup May 9, 2019, 8:22 PM

#

probs crashes their game

#

which isn't my problem if they modified it when they shouldn't have

#

kappa

winged badger May 9, 2019, 8:22 PM

#

just make sure you don't modify it client side

solar stirrup May 9, 2019, 8:23 PM

#

Yeah I won't

#

If I need to, I just call an RPC from the PlayerController to the server right?

#

i.e. moving an item from slot 1 to 2

winged badger May 9, 2019, 8:24 PM

#

well, an InventoryComponent would be better

#

no need to clutter the PC

solar stirrup May 9, 2019, 8:24 PM

#

can I do it from the inventory component itself??

#

oof

winged badger May 9, 2019, 8:24 PM

#

sure, as long as its a component on your PC, PS or Pawn

solar stirrup May 9, 2019, 8:24 PM

#

What RPC type do I use?

winged badger May 9, 2019, 8:24 PM

#

PS might be ideal, since it survives the player disconnecting

#

only thing that does

solar stirrup May 9, 2019, 8:25 PM

#

If I put it on the pawn and the player disconnects

#

do I have time to save the inventory?

winged badger May 9, 2019, 8:25 PM

#

no

solar stirrup May 9, 2019, 8:25 PM

#

aight I'll put it on the player state then

winged badger May 9, 2019, 8:26 PM

#

well, you do, but it would require some more complicated overrides

#

and again, only place you could actually save it at is inactive PS

solar stirrup May 9, 2019, 8:26 PM

#

thought as much

tall pine May 9, 2019, 8:27 PM

#

What's the best way to save / restore Player Info across non-seamless travel?
Right now I'm thinking creating a SaveGameObject, write info to it, then save / load when needed.
My problem is that I do want to save PlayerState, but how do I create a PlayerState inside the SaveGameObject?
I'm doing it in C++

winged badger May 9, 2019, 8:28 PM

#

you don't, ever thought about doing it the other way around?>

#

also

#

hard travel means there is no PS for that player during the travel

#

and new one is created

#

which doesn't leave you an overabundance of options

tall pine May 9, 2019, 8:30 PM

#

yeah it's not up to me. The project is decided to have non-seamless travel.
Anyway, so I can't save the entire PlayerState whatsoever?

winged badger May 9, 2019, 8:30 PM

#

you would need to associate the save game object with the player

#

still not sure the PS would survive as an object

#

and also a fun fact, replicating a UObject doesn't work out of the box

tall pine May 9, 2019, 8:33 PM

#

So say inside the SaveGameObject, I put a PlayerState* SavedPlayerState;
THen when a player needs to save his player state, he passes his PS into the SaveGameObject, along with his name to it.
Then I save it. THen travel to a new map, load the SaveGameObject for that player, then copy over the PS?

winged badger May 9, 2019, 8:34 PM

#

seems hacky

tall pine May 9, 2019, 8:34 PM

#

How else can I do it?

winged badger May 9, 2019, 8:34 PM

#

would be better to just keep a struct in PS that has all the info that needs to be saved

#

then carry that over

tall pine May 9, 2019, 8:34 PM

#

Well again, that's seamless travel right?

winged badger May 9, 2019, 8:34 PM

#

doesn't really matter

#

with seamless you wouldn't need any of this

grizzled stirrup May 9, 2019, 8:35 PM

#

With seamless do any PS properties for any players stay between maps?

tall pine May 9, 2019, 8:35 PM

#

I thought PS won't survive non-seamless travel, so why would anything stored in PS would carry over?

thin stratus May 9, 2019, 8:35 PM

#

With "carry that over" i think Zlo meant into the SaveGame?

#

Some of the Properties stay, but your own only if you move them by hand via CopyProperties

tall pine May 9, 2019, 8:36 PM

#

@grizzled stirrup : yes, and you can use CopyProperties() to copy specific stuff over

thin stratus May 9, 2019, 8:36 PM

#

Well and OverrideWith

winged badger May 9, 2019, 8:36 PM

#

CopyProperties won't work with hard travel

grizzled stirrup May 9, 2019, 8:36 PM

#

Very interesting! I've been storing them in the client GameInstance (since the client can set his own properties), but this is very useful!

tall pine May 9, 2019, 8:36 PM

#

I know, I'm answering Kylekatarn.

#

In my case, that's why I'm asking about saving it to a SaveGameObject and then load it after travel

thin stratus May 9, 2019, 8:37 PM

#

@winged badger I think you confused them by saying "doesn't matter" to SeamlessTravel yes/no and at the same time stating that you can just put a struct into the PS that carries over to the next map

#

Cause as far as PS stuff carrying over goes, it should be done via SeamlessTravel

winged badger May 9, 2019, 8:38 PM

#

what i meant is it doesn't matter if travel is seamless or not, method of copying struct into SaveGameObject uniquely keyed to a player, then copying it back after travel would work

thin stratus May 9, 2019, 8:38 PM

#

Yeah I figured you mean "carry over" in combination with savegames

winged badger May 9, 2019, 8:38 PM

#

ofc, need a method to persist the SaveGameObject as well

thin stratus May 9, 2019, 8:38 PM

#

It just read like you meant without

#

So carry over via SaveGame doesn't need Seamless.
Carry over via surviving in the PlayerState needs Seamless.

#

(which I know, just making sure peeps are not confused)

winged badger May 9, 2019, 8:39 PM

#

which is... hacky as you would have to store it in GI

#

on the server

tall pine May 9, 2019, 8:39 PM

#

@winged badger : that only copy over whatever custom stuff you add for the custom PS right? As for the base PS, such as name, score, etc. that wouldn't carry over the struct

thin stratus May 9, 2019, 8:39 PM

#

You can either save all data in the GI or just save the SaveGame and load it later.

#

Both require you to pass it to the Server again.

#

Or you save it directly on the Server's GI

#

But then you need a unique identifier to grab it posttravel

solar stirrup May 9, 2019, 8:40 PM

#

I was wondering, do I need to implement NetSerialize() for the FFastArraySerializerItem I'm using or is that optional @winged badger ?

thin stratus May 9, 2019, 8:40 PM

#

Tricky question @solar stirrup That's why no one is answering it :P

winged badger May 9, 2019, 8:40 PM

#

you don't, it will work out of the box

thin stratus May 9, 2019, 8:40 PM

#

I haven't used it otherwise I would have answered it for you already

winged badger May 9, 2019, 8:40 PM

#

as long as you kept within NetSerialization.h header example confines

solar stirrup May 9, 2019, 8:40 PM

#

I was wondering if it was required or not ^^ I might implement it later

#

although I'd assume UE4 already does a good job at serializing

grizzled stirrup May 9, 2019, 8:41 PM

#

For the identifier there, would you store one per client in the server's GI and one on each client locally in their GI, and have them basically ask for the server to set its PS properties on load of the new map?

winged badger May 9, 2019, 8:41 PM

#

i would just seamless travel

#

as its made exactly for that scenario

grizzled stirrup May 9, 2019, 8:42 PM

#

Luckily I can for my game

#

Will use CopyProperties to bring across my current player upgrades struct to the new map

thin stratus May 9, 2019, 8:42 PM

#

It is recommended by epic to perform all possible travels seamless

grizzled stirrup May 9, 2019, 8:43 PM

#

So just the initial hard travel (steam listen server), then go seamless while connected?

thin stratus May 9, 2019, 8:43 PM

#

Obviously not possible are hard connections to servers and back to the mainmenu etc.

winged badger May 9, 2019, 8:43 PM

#

yes

thin stratus May 9, 2019, 8:43 PM

#

Yes, as long as you are connected it is adviced to only perform seamless travels

fleet raven May 9, 2019, 8:43 PM

#

seamless travel crashes my game br_oof

grizzled stirrup May 9, 2019, 8:43 PM

#

Great sounds like a perfect solution

#

😄

thin stratus May 9, 2019, 8:43 PM

#

Otherwise you are basically kicking everyone and letting the mreconnected

tall pine May 9, 2019, 8:43 PM

#

Yes, but my senior argues that he faces so many engine problem with seamless travel before, so now he just wants to do hard travel

Anyway, I'll try to use SaveGameObject way

thin stratus May 9, 2019, 8:44 PM

#

Your Senior does it wrong then

winged badger May 9, 2019, 8:44 PM

#

i hate to break it to you, but your senior isn't a senior

thin stratus May 9, 2019, 8:44 PM

#

Seamless Travel is perfectly stable. We use it throughout our full game.

#

It only breaks if you have no idea what you are doing

#

(not counting engine bugs which I never had with seamless travel outside of PIE)

winged badger May 9, 2019, 8:45 PM

#

working around things that work out of the box is usually what people new at unreal do

tall pine May 9, 2019, 8:45 PM

#

Ha ha, I think it's a collection of people, and problems they created. He probably just got tired of fixing all the seamless traveling crashes
Cause my game does crash when I seamless travel back and forth.

thin stratus May 9, 2019, 8:45 PM

#

Well, good luck

#

Hope you aren't gonna use Steam :P

#

Or any other Subsystem that has issues with reconnecting clients

tall pine May 9, 2019, 8:46 PM

#

Not my code, and I'll have to track down / fix / convince the entire network team to switch their code to seamless

thin stratus May 9, 2019, 8:46 PM

#

Cause they require SeamlessTravel

fleet raven May 9, 2019, 8:46 PM

#

why would steam have issues with players reconnecting

thin stratus May 9, 2019, 8:46 PM

#

My goodness a complete team of people who have no idea >.>

fleet raven May 9, 2019, 8:46 PM

#

seems like steam not so good after all

winged badger May 9, 2019, 8:46 PM

#

it usually goes like this:
1 - person misunderstands something
2 - he implements a workaround the engine
3 - continues to build on the erroneous assumption, making the code more convoluted with each iteration
4 - things finally go back to the drawing board, after everything explodes

thin stratus May 9, 2019, 8:46 PM

#

Cause if you ServerTravel non-seamless, Clients won't follow @fleet raven

#

They will get kicked out of the session

fleet raven May 9, 2019, 8:47 PM

#

so they reconnect and everything is fine

thin stratus May 9, 2019, 8:47 PM

#

Yeah but they don't do that automatically

fleet raven May 9, 2019, 8:47 PM

#

but they do

winged badger May 9, 2019, 8:47 PM

#

you can make them reconnect using lobbies

thin stratus May 9, 2019, 8:47 PM

#

So a simple map change on a running game is gonna reset them to the main menu

fleet raven May 9, 2019, 8:47 PM

#

it works just fine by default

thin stratus May 9, 2019, 8:47 PM

#

It's known that Steam requries Seamless Travel. ¯_(ツ)_/¯

fleet raven May 9, 2019, 8:47 PM

#

if you aren't using an online sub

grizzled stirrup May 9, 2019, 8:47 PM

#

By default steam listen server clients can reconnect to the match if they lose connection while playing?

thin stratus May 9, 2019, 8:48 PM

#

as already stated, ServerTarvels should if possible be seamless

#

Makes 0 sense to send connected clients through the whole login process again

fleet raven May 9, 2019, 8:48 PM

#

that's true

tall pine May 9, 2019, 8:49 PM

#

My senior mentioned this to me:

in seamless travel, loading screen is processed on main thread, which means you may see the hitch on your animated icon because the level is loaded in time sliced fashion

Is this true? Can this be solved?

thin stratus May 9, 2019, 8:49 PM

#

@grizzled stirrup By default everyone can just find the Server again and join if it's still online

grizzled stirrup May 9, 2019, 8:49 PM

#

Using the steam beacon setup, would it be similar?

winged badger May 9, 2019, 8:49 PM

#

just google unreal loading screen

fleet raven May 9, 2019, 8:49 PM

#

what's up with this, why would they not just reset the thing that overflows on seamless travel

📎 unknown.png

winged badger May 9, 2019, 8:49 PM

#

and top result will be a wiki entry with how to use MoviePlayer for loading screen

#

which runs on its own thread

thin stratus May 9, 2019, 8:50 PM

#

@fleet raven Because that time persists

fleet raven May 9, 2019, 8:50 PM

#

but it doesn't have to

thin stratus May 9, 2019, 8:50 PM

#

They rather reset everything

fleet raven May 9, 2019, 8:50 PM

#

there's no need for it to persist to a new map

thin stratus May 9, 2019, 8:50 PM

#

ask epic ¯_(ツ)_/¯

#

@grizzled stirrup Probably, it's also just sessions

#

@tall pine Maybe, but that's not a reason to not allow SeamlessTravel.

#

Sounds more like a weak excuse

winged badger May 9, 2019, 8:51 PM

#

its for persistant worlds on dedicated servers

#

which run into that floating point error with time when running over 2 days straight

fleet raven May 9, 2019, 8:51 PM

#

it can't be for that either

winged badger May 9, 2019, 8:51 PM

#

lose precision

fleet raven May 9, 2019, 8:51 PM

#

there would be no reason to not reset it every time

tall pine May 9, 2019, 8:51 PM

#

ah no, just one example, since I don't know enough about networking to debate with him. I do get seamless traveling to work yesterday, but the game does crash if I travel back and forth a couple times between levels

fleet raven May 9, 2019, 8:51 PM

#

if you have to reset it eventually anyway

thin stratus May 9, 2019, 8:52 PM

#

@tall pine If it crashes look at the crashlog and check what you are doing wrong

#

We are traveling countless times and it's all fine

winged badger May 9, 2019, 8:52 PM

#

if you look at lot of games using dedicated servers with persistent instances, they tend to have,,, daily maintenance

fleet raven May 9, 2019, 8:52 PM

#

🤔

#

can we just make the world timeseconds a double to fix it

winged badger May 9, 2019, 8:53 PM

#

someone tried a few months ago

#

pretty sure it was a total failure

fleet raven May 9, 2019, 8:53 PM

#

you probably have to patch more than one usage of it

thin stratus May 9, 2019, 8:53 PM

#

If it would be easy to solve, it wouldn't exist

manic pine May 9, 2019, 8:53 PM

#

its prolly copied over to a lot of floats

#

e.g. "animationstarttime: worldseconds"

#

some builtin way of resetting it would be nice though

thin stratus May 9, 2019, 8:54 PM

#

Everywhere you use it it needs doubles

fleet raven May 9, 2019, 8:54 PM

#

well a server that stops functioning after 2 days is not an option either

manic pine May 9, 2019, 8:54 PM

#

without restarting a map

thin stratus May 9, 2019, 8:54 PM

#

BP would already fail

winged badger May 9, 2019, 8:55 PM

#

thats why you do 10 minute daily maintenance

#

just restart the thing

thin stratus May 9, 2019, 8:55 PM

#

Most Servers restart during the night yop

fleet raven May 9, 2019, 8:55 PM

#

well I have a case where people want to run their stuff for weeks and there is no reason it would be changing the map either

#

:(

manic pine May 9, 2019, 8:56 PM

#

yeah and what about singleplayer games

fleet raven May 9, 2019, 8:56 PM

#

do people play those for 2 days at once

thin stratus May 9, 2019, 8:56 PM

#

It's simply not a thing to have the game run for weeks without restarting the server

fleet raven May 9, 2019, 8:56 PM

#

but it could be, if it was a double

thin stratus May 9, 2019, 8:56 PM

#

It will give problems at some point

#

Yeah but it can't be a double

manic pine May 9, 2019, 8:56 PM

#

well, its conceivable they might at least tab out and let it run background

thin stratus May 9, 2019, 8:56 PM

#

Everything that uses them would need to be a double

#

And BP don't even support double

manic pine May 9, 2019, 8:57 PM

#

but even if not, there's the saving/loading issue

thin stratus May 9, 2019, 8:57 PM

#

And even double isn't endless

#

Restarting the server every night when no one plays is the way to go

#

Bigger games that have 99.999% online time aren't using one Server

#

They are also not using DedicatedServers by epic

winged badger May 9, 2019, 8:58 PM

#

and its not just unreal, the other engines have the same limitation

fleet raven May 9, 2019, 8:58 PM

#

torque engine servers could run for a whole month before failing

thin stratus May 9, 2019, 8:58 PM

#

But they fail eventually

#

so what does it matter

fleet raven May 9, 2019, 8:58 PM

#

a month is much less inconvenient than every day

thin stratus May 9, 2019, 8:59 PM

#

As said, persistent worlds aren't using ue4s dedicated servers most likely

#

UE4s servers are meant for matchbased stuff like UT

#

They restart every night probably. Ever had a Counter Strike Server back in the days?

#

Same thing

manic pine May 9, 2019, 9:00 PM

#

a builtin mechanic would be nice though

#

e.g. reset worldtime every 24 hours, with corresponding events on actors and components

twin juniper May 9, 2019, 9:01 PM

#

How do you even tell players apart on a listen server when every single player controller is always zero on each client?

fleet raven May 9, 2019, 9:01 PM

#

you don't use the index

winged badger May 9, 2019, 9:02 PM

#

that static accessor for the PC is pretty much terrible for people just starting out with networking

thin stratus May 9, 2019, 9:02 PM

#

Player's each have a PlayerState.

winged badger May 9, 2019, 9:03 PM

#

its best not to use it at all unless you understand what it does where

thin stratus May 9, 2019, 9:03 PM

#

This comes (in C++) with a proper UniqueID.

#

That UniqueID could even persist between servers if using a subsystem like Steam (steamID)

#

The PlayerState can be accessed via PlayerController and possess Pawn (Character)

#

So you have a lot of points to grab the Player

manic pine May 9, 2019, 9:04 PM

#

or just gamestate

thin stratus May 9, 2019, 9:04 PM

#

Oh yeah GameState has the PlayerArray

fleet raven May 9, 2019, 9:04 PM

#

trying to store a custom id in that unique id thing is so overcomplicated lol

thin stratus May 9, 2019, 9:04 PM

#

However that is not in sync on client and server

winged badger May 9, 2019, 9:04 PM

#

i lost count on how many people used GetPlayerController[0] to access the controller from its possessed pawn

thin stratus May 9, 2019, 9:04 PM

#

Is it? Usually you just make your own child of the FUniqueIdRepl and that's it

manic pine May 9, 2019, 9:05 PM

#

getplayercontroller is the worst function ever created, yes

winged badger May 9, 2019, 9:05 PM

#

then switched to dedicated servers and everything exploded

thin stratus May 9, 2019, 9:06 PM

#

Yeah same goes for GetPlayerCharacter

#

Then again, you need them when doing Splitscreen stuff

#

It's the only place where I currently use them, to grab the local players

manic pine May 9, 2019, 9:06 PM

#

ah yeah, that mess

winged badger May 9, 2019, 9:07 PM

#

i mean, the function itself isn't terrible in what it does

#

its just that it tends to prevent a lot of people from learning how things work

thin stratus May 9, 2019, 9:08 PM

#

It's the way it's shared that is wrong

#

Most tutorials always use it

#

Never explain it

manic pine May 9, 2019, 9:08 PM

#

hmm the only time i ever used it was the very first time i made a blueprint

#

and had no idea how it worked

#

since then ive never needed it

fleet raven May 9, 2019, 9:09 PM

#

is it not normal to read the pinned pdf before starting to do anything with mp

manic pine May 9, 2019, 9:09 PM

#

nah, you start doing stuff first then read when you encounter a problem

winged badger May 9, 2019, 9:09 PM

#

i did use it with GetGameMode->GetNumPlayers->for(0 to num -1) do something, when prototyping

manic pine May 9, 2019, 9:09 PM

#

first you ask*

winged badger May 9, 2019, 9:10 PM

#

its the simplest way to iterate through all PCs from BP

manic pine May 9, 2019, 9:10 PM

#

well in fairness, the server can and should use it

#

its the only way of going through the pcs since you cant get pc from playerstate

#

or is it pawn you cant get?

winged badger May 9, 2019, 9:12 PM

#

getowner->cast

#

pawn is worse, getowner->casttocontroller->getpawn

manic pine May 9, 2019, 9:12 PM

#

yeah, nasty indirection

winged badger May 9, 2019, 9:13 PM

#

i tend to have a TWeakObjectPtr for the pawn in the PS

manic pine May 9, 2019, 9:13 PM

#

i think a pawn reference in ps should be default

#

i always do that too ye

#

so other clients can tell which pawn a player(state) controls

tall pine May 9, 2019, 9:18 PM

#

@winged badger : I'm searching around and see this regards to loading screen:

#

Hi everyone,

So we are using seamless travel as part of our matchmaking flow (so that we don't drop the connection when traveling from the main menu to the game map). We've noticed that loading screens (which we have implemented using a separate module with the DefaultGameMoviePlayer) don't work properly with seamless travel - PlayMovie() never gets called because the PreLoadMap delegates never get fired from the seamless loading path, and it appears that PostLoadMap fires from the seamless travel handler as soon as the persistent map loads, which is before everything seems to be loaded.

I made our load screen code call PlayMovie for us when seamless travelling instead of relying on PreMapLoad to call it, but the normal EngineLoop::Tick() calls WaitForMovieToFinish() which tears the movie down right away.

My gut feeling is that we're going to have to roll our own solution for this but I thought I'd put it out there in case there's something already in the engine I don't know about...

winged badger May 9, 2019, 9:19 PM

#

if your PC class changes from PC1 on Level1 to PC2 on Level2

#

and you travel from Level1 to Level2

#

NotifyWorldLoaded will fire on PC1, not PC2

#

as it fires before the GM swaps the controllers

fleet raven May 9, 2019, 9:21 PM

#

huh so that's what the swap pc functionality is for

winged badger May 9, 2019, 9:22 PM

#

that would be one of unfortunate caveats i mentioned earlier

#

so you might want to consider using some other hook to stop the movieplayer

#

PC fires NotifyLoadedWorld, then ServerNotifyLoadedWorld

#

after that GM swaps controller to the new class

#

then calls HandleSeamlessTravelPlayer

#

which calls either ClientInitializeHUD or GenericPlayerInitialization that calls ClientInitializeHUD, don't remember

#

when client receives that RPC, it will instantiate a HUD

#

which is a decent enough hook to get rid of a loading screen

fleet raven May 9, 2019, 9:27 PM

#

btw what is the point of transition map for seamless travel? why not pop up a load screen, unload the first, load the next? no need for the extra one

winged badger May 9, 2019, 9:27 PM

#

you have to be on a map afaik

#

so you're there while loading and unloading is done

#

its bFinalDestination is false

tall pine May 9, 2019, 9:28 PM

#

IT's also bad if you have 2 big map in memory. Transition map is small and in between

fleet raven May 9, 2019, 9:28 PM

#

no don't have both maps at once

winged badger May 9, 2019, 9:28 PM

#

so it will not trigger any world loaded events, namely not ServerNotifyWorldLoaded

fleet raven May 9, 2019, 9:28 PM

#

just unload one and load the next as part of the same method

tall pine May 9, 2019, 9:28 PM

#

you will if you don't have transition map

twin juniper May 9, 2019, 9:29 PM

#

Do you need to port forward a listen server? Or is it always required unless you use steam etc?

winged badger May 9, 2019, 9:29 PM

#

unless you use a service that comes with NAT punchthrough, like steam does

#

you do

manic pine May 9, 2019, 9:29 PM

#

yeah its not about the game, its about the computer

#

it wont receive the connection

winged badger May 9, 2019, 9:31 PM

#

@tall pine HUD, not being replicated cannot persist during seamless travel

#

the ULocalPlayer Viewport is kept alive from GameInstance, so it does

#

so any widgets you managed to add to the Viewport and failed to remove as you initialized seamless travel

#

will happily remain there, referenced by the Viewport

tall pine May 9, 2019, 9:32 PM

#

@winged badger : that's fine, I use a different HUD anyway. Either way, I can't use seamless since it's a team decision.

As for saving PlayerState into a SaveGameObject, how do you copy over the stuff in the PlayerStateBase? Just have to copy it one by one?

winged badger May 9, 2019, 9:33 PM

#

pretty much, its an exceptionally inelegant approach

#

and those are the consequences using it

tall pine May 9, 2019, 9:34 PM

#

<sigh> ok thank you Zlo for your help. I really appreciate it

grizzled stirrup May 9, 2019, 10:40 PM

#

Is ACharacter::OnPossessed ONLY ever called on the server?

#

The source says this as a comment /** * Called when this Pawn is possessed. Only called on the server (or in standalone).

#

or in standalone does that mean single player? Or a listen server host?

winged badger May 9, 2019, 10:45 PM

#

single player, but applies to listen server host as well

tall pine May 9, 2019, 10:48 PM

#

In hard-travel, does the client disconnect / reconnect from the server everytime they travel using ClientTravel() ?

#

I'm asking since I'm unclear when reading the doc about Travelling:

APlayerController::ClientTravel
If called from a client, will travel to a new server

If called from a server, will instruct the particular client to travel to the new map (but stay connected to the current server)

So in case A, the client will disconnect from a server, travel to a new map, and connect to a new server? What if I don't want that to happen? THen I need to somehow request the server to call ClientTravel() on that client?

grizzled stirrup May 9, 2019, 11:15 PM

#

Thanks Zlo!

cedar finch May 9, 2019, 11:39 PM

#

Can somebody please help me with this simple replication? There's gotta be something I'm missing. I put a print string in to test and the client is not even executing the "ServerGibZombies" event. Why? https://i.gyazo.com/0ad84e3ba4070f944d819ed0f5a111fd.png

tall pine May 9, 2019, 11:41 PM

#

Why would Remote pin go to Server Gib Zombies? Wouldn't that only be called on Server?

grizzled stirrup May 9, 2019, 11:41 PM

#

It'd be a server RPC I assume which a client would call to go to the server

winged badger May 9, 2019, 11:42 PM

#

you do know that Server RPC called from server is just a normal function?

#

that switch is redundant

cedar finch May 9, 2019, 11:42 PM

#

I thought the "remote" pin is the non server player

winged badger May 9, 2019, 11:42 PM

#

as for why its not executing, relevant part is missing

#

it is, but you can call Server RPC from server just fine

grizzled stirrup May 9, 2019, 11:44 PM

#

@winged badger is it equally as cheap to call a Server function on the server as it is any other?

#

I often had branches saying if Role < Role Authority and calling the RPC only there, then calling the function the RPC calls directly if Authority

winged badger May 9, 2019, 11:45 PM

#

in this case it would be cheaper, very slightly, to call multicast directly, but if you need that blueprint macro to check auth first, then its more expensive, and worse, more verbose

cedar finch May 9, 2019, 11:45 PM

#

I must be missing what your saing. So I thought that when a client wants to do something and then let everyone else know what he did, he has to call a Server RPC then a Multicast.

winged badger May 9, 2019, 11:46 PM

#

it could be your mesh is null, you're calling the RPC from an object that can't do it, few other things

#

can't tell from your screenshot

tall pine May 9, 2019, 11:47 PM

#

@winged badger : would you mind taking a look at my question above? Thank you

cedar finch May 9, 2019, 11:48 PM

#

So my character has his "hit" event https://i.gyazo.com/38644c842ceab9ef55f64924e3acbeb5.png Then the zombie recieves the message. https://i.gyazo.com/ead59f4a54a4f0a1342dd524a23a5e30.png and the gibbing stuff above is plugged into that event

winged badger May 9, 2019, 11:49 PM

#

zombie can'

#

can't call a server RPC, it has no DataChannel

#

you need to RPC in character

#

@tall pine pretty much, its called Seamless Travel 😛

cedar finch May 9, 2019, 11:51 PM

#

Ah! Ok I knew I was missing something. Thanks. I thought I was crazy or something

#

So handeling gibbing for enemies can't be done inside the actual enemy? What's a good place to handle it?

winged badger May 9, 2019, 11:52 PM

#

it can, server RPC can't

#

EventHandleEnemyWasHit has to be called on server, not on client

cedar finch May 9, 2019, 11:53 PM

#

Oh yea. lol Ok I gotcha.

tall pine May 9, 2019, 11:57 PM

#

@winged badger : ha ha. So that block of text is only true for Seamless travel? this:

APlayerController::ClientTravel
If called from a client, will travel to a new server

If called from a server, will instruct the particular client to travel to the new map (but stay connected to the current server)

#

I'm trying to find a good place to save / load PlayerState stuff. If the client disconnect everytime they hard-travel, then I can probably hook into login(), logout() ?

winged badger May 10, 2019, 12:16 AM

#

after calling Super:: in PostLogin

#

otherwise you won't have a playerstate to load to

#

and before calling Super:: in ClientTravel

tall pine May 10, 2019, 12:18 AM

#

I call ClientTravel from APlayerController*. Seems that PostLogin() is called from GameMOde

grand kestrel May 10, 2019, 6:36 AM

#

Whats the cost of replicating a UObject pointer?

#

I assume epic does something so we're not all replicating uin64's?

#

Think I found the answer myself "if you have a UObject property that is replicated, the reference to that object will be sent over the network as a special ID that is assigned by the server. This special ID is a FNetworkGUID"

#

So its a uint32

#

So probably still worth assigning and replicating uint8 IDs manually for things that happen a lot

wet tangle May 10, 2019, 9:06 AM

#

Does anyone know af a way to get the cause of join session failure on a packaged project?

thin stratus May 10, 2019, 9:07 AM

#

Usually in the Logs?

#

You can also use the TravelFailure node/function to check why it failed by printing the reason

#

However the log is almost always more informative

wet tangle May 10, 2019, 9:09 AM

#

ty

lone vapor May 10, 2019, 9:41 AM

#

Has anyone seen this before? I can't figure out why the server gets a different socket rotation to the client. Everything is replicated, all of the character components, capsule, meshes, etc.
I'm setting the weapon as a child actor of the player character and setting the "parent socket" as the grip point.

📎 unknown.png

meager spade May 10, 2019, 9:43 AM

#

make sure server is ticking bones

#

its off by default

grand kestrel May 10, 2019, 9:48 AM

#

Getting a bit frustrated. I need to add a tick prerequisite for the world tick, but theres no tick function to bind to.. 😦 Because of this, PostNetReceive is being called randomly before or after (stemming from world tick) my tick function

#

And I need a tick that ticks after replicated values are received

slim holly May 10, 2019, 9:49 AM

#

ticking bones is super duper expensive

#

create data that drives the bone rotation, replicate the data

lone vapor May 10, 2019, 9:54 AM

#

what data am i replicating tho? both the server and client are sharing the same player blueprint, the same weapon blueprint and assets, so the socket info should all be the same. Not sure where this slight Z rotation is coming from though :3

slim holly May 10, 2019, 10:08 AM

#

generally control rotation is used for aiming

#

but you can create your own form of rotation data and replicate that

#

remember kids, Meshes and skeletons are only visual presentations of the data

grand kestrel May 10, 2019, 10:25 AM

#

Wouldn't say 'only'

#

Root motion is a good example

#

So is parenting a collider under a bone

#

Just have to know what you're doing first 🤷

slim holly May 10, 2019, 10:30 AM

#

true, but the skeleton inside the collider can be anything

#

you can actually do root motion the other way around, not even that difficult to drive animations based on travel distance

vernal hollow May 10, 2019, 10:31 AM

#

anyone have any idea why my RInterpTo would be running slower/taking longer on a client than on the host?

slim holly May 10, 2019, 10:32 AM

#

depends who sets the target value

#

usually servers don't do interpolation

vernal hollow May 10, 2019, 10:36 AM

#

it's used to set the actors rotation to the direction they're moving and even when it's only running on a client it's way less snappy than on the host client

#

i thought it was a case of the server trying to set it and the client only rotating based on that value but i'm pretty sure it isnt that

slim holly May 10, 2019, 10:36 AM

#

that's an authority issue of who gets to set the rotation

#

if you're seeing stuttering on client, that means server is trying to correct the client based on old information

#

but, if you must keep it server authorative, you can replicate the interpolation target to server before doing the actual interpolation

#

instead of sending the interpolated data

#

that should keep it synced assuming both ends are interpolating at ~same speed

vernal hollow May 10, 2019, 10:44 AM

#

a quick aside relating to how i was testing everything, if i wrapped my code running in the tick statement with a check to see if it's locally controlled before running it, would that make it exclusively run on the client?

#

that was one of the ways i've been testing it's behaviour

grizzled stirrup May 10, 2019, 11:26 AM

#

That would return true if a client OR a listen server host

vernal hollow May 10, 2019, 11:28 AM

#

but it wouldn't run on a dedicated server right? just the client in that instance

grizzled stirrup May 10, 2019, 11:28 AM

#

Correct

#

The dedicated server doesn't have any local controllers

thin stratus May 10, 2019, 11:29 AM

#

Also, it only returns true on the PlayerController OF the ListenHost.
Given the Server has all Controllers.

#

Just to make sure that's clear

#

So it's basically the most effective way of limiting something to the owner of the Pawn/Controller

#

May it be a client or the host

grizzled stirrup May 10, 2019, 11:31 AM

#

Question: what is the best way to "reset" RepNotify properties? Say I don't replicate the character movement component and instead send regular RPCs from the client to the server to update position and rotation. Since I don't have the CMC running on remote client proxies, there's no way for them to tell if they have landed, so I can push an OnRep bool bLanded to the server via an RPC whenever the controlling client lands. In order to make the OnRep event trigger on each landing to all other clients, bLanded has to be reset on the server before it can be activated again, which will still replicate down to clients but do nothing (as I have gated the OnRep_Landed event with an if (bLanded) check before doing any land events / anims.

#

So in short, is it common to reset a RepNotify property on the server using a short timer after setting it?

#

Even if resetting it wastes some bandwidth to send the false bool down to clients that otherwise runs nothing else?

vernal hollow May 10, 2019, 11:33 AM

#

this is what my interp issue is doing on a client vs a host with the islocallycontrolled check to try have it only run on the clients

#

https://streamable.com/jfr0g

Streamable

ue4 jitter - Streamable

▶ Play video

#

the first one is the host and is how it should be, the second is the client with it's jitter

thin stratus May 10, 2019, 11:39 AM

#

@grizzled stirrup Why would the CMC not execute the landed on Simulated?

grizzled stirrup May 10, 2019, 11:40 AM

#

I have the CMC replication fully off, so the proxies are being just interpolated via SetActorLocation / Rotation

thin stratus May 10, 2019, 11:40 AM

#

Oh

grizzled stirrup May 10, 2019, 11:40 AM

#

So I don't think the CMC would know about landing

thin stratus May 10, 2019, 11:40 AM

#

Well the proper way is to check on each client if they landed

#

When you are interpolating

#

I mean, turning off the CMC replication is removing a lot of features :D

#

Also this is better suited for an RPC than an OnRep if you do it like that

#

No one cares about the landed event 10 seconds later

#

It's a one time event

grizzled stirrup May 10, 2019, 11:42 AM

#

Yeah it is removing a lot of features (mainly losing speed and delegates like OnLanded)!

#

Would you use a multicast RPC in this case then?

#

When landed

thin stratus May 10, 2019, 11:42 AM

#

You are losing access to all sorts of information, like the MovementMode etc.

grizzled stirrup May 10, 2019, 11:42 AM

#

When the controlling client lands, he sends a server RPC to say he landed which sends a multicast RPC to all other clients

thin stratus May 10, 2019, 11:42 AM

#

The Server should already know if you landed

grizzled stirrup May 10, 2019, 11:42 AM

#

Yeah that's fine, the other players just need to see them generally where they are in the world

thin stratus May 10, 2019, 11:42 AM

#

And send an RPC then

#

But even that is crap tbh

grizzled stirrup May 10, 2019, 11:43 AM

#

It's fully client authoritive movement

thin stratus May 10, 2019, 11:43 AM

#

That's delayed as fuck

grizzled stirrup May 10, 2019, 11:43 AM

#

So the server doesn't know

thin stratus May 10, 2019, 11:43 AM

#

Yeah you need to do this stuff in the interpolation code

grizzled stirrup May 10, 2019, 11:43 AM

#

Until he gets a packet from the client with a location / rotation struct

thin stratus May 10, 2019, 11:43 AM

#

Check if they were falling before

#

And then if they aren't anymore

#

You can't time this otherwise

#

With a higher ping, the OnLanded will come in long after the player actually landed

grizzled stirrup May 10, 2019, 11:43 AM

#

That's a good point

thin stratus May 10, 2019, 11:44 AM

#

That's why the CMC performs the movement on all clients

#

And is only replicating the info for that

#

You can also turn of the Client correction on the Server in the CMC

grizzled stirrup May 10, 2019, 11:44 AM

#

I'll have to look into the client authority CMC features

thin stratus May 10, 2019, 11:44 AM

#

So I don't know why you'd go as far as turning off teh replication

#

It brings more problems than it solves

grizzled stirrup May 10, 2019, 11:44 AM

#

If I turn off the client correction, he won't be where he is on the server though would he?

thin stratus May 10, 2019, 11:44 AM

#

The Server would accept the Client location

#

Instead of overriding it

grizzled stirrup May 10, 2019, 11:45 AM

#

Oh that's exactly what I want

#

Damn

#

I thought turning off client correction would just simulate server / client on separate paths

#

That's great thank you I'll have a look into that noww

thin stratus May 10, 2019, 11:45 AM

#

Check ::ServerMoveHandleClientError

grizzled stirrup May 10, 2019, 11:45 AM

#

Hopefully I can then still replicate the client movement as usual from the server to other clients using this method

thin stratus May 10, 2019, 11:46 AM

#

As well as ::ServerCheckClientError

#

Line 8501 on 4.20

#

// Check location difference against global setting
    if (!bIgnoreClientMovementErrorChecksAndCorrection)
    {

#

Might need a tad additional code

#

But I would assume inheriting from the CMC and overriding 1-2 function is still better than fighting the non-rep fight

#

@jolly siren might be able to say something about making it client authoritive

grizzled stirrup May 10, 2019, 11:47 AM

#

Thank you so much this is really useful

#

I'd love to use the CMC if possible as it does so many great things

#

Looking into this code now

thin stratus May 10, 2019, 11:48 AM

#

Also

#

Line 8462

#

if (GetDefault<AGameNetworkManager>()->ClientAuthorativePosition)

#

So basically if the test passes

#

Which happens if that boolean from above is true of course

#

Then it goes into the else of the ServerMoveHandleClientError function

#

And in there is the line with ClientAuthoritivePosition

#

If that is true, then it will most likely take all of the client

jolly siren May 10, 2019, 11:49 AM

#

Yeah we use bIgnoreClientMovementErrorChecksAndCorrection and ClientAuthorativePosition

thin stratus May 10, 2019, 11:49 AM

#

And accept it

#

Tada

#

I KNOW MY CMC

#

And I hate it

#

@grizzled stirrup

grizzled stirrup May 10, 2019, 11:50 AM

#

Damn this is amazing

#

So a quick repro for a noob like me:

In the character constructor:

GetCharacterMovement()->bIgnoreClientMovementErrorChecksAndCorrection = true;

#

Then for the ClientAuthorativePosition boolean, how do I set that?

#

It's not showing up at least publicly from the GetCharacterMovement() getter in the Character

thin stratus May 10, 2019, 11:51 AM

#

it's part of the GameNetworkManager

#

might be a project setting or so

#

Or not

#

Guess it's a config variable then

jolly siren May 10, 2019, 11:52 AM

#

yeah it's in the ini

thin stratus May 10, 2019, 11:52 AM

#

Do you have the exact lines to paste, Ethan?

grizzled stirrup May 10, 2019, 11:52 AM

#

Would be extremely helpful, thank you so much!

jolly siren May 10, 2019, 11:52 AM

#

[/Script/Engine.GameNetworkManager]
MAXPOSITIONERRORSQUARED=1600
ClientAuthorativePosition=true

grizzled stirrup May 10, 2019, 11:52 AM

#

By just setting these two bools, do we get all the benefits of the CMC while allowing the client to determine position?

jolly siren May 10, 2019, 11:52 AM

#

In DefaultGame.ini

grizzled stirrup May 10, 2019, 11:52 AM

#

Thank you so much

thin stratus May 10, 2019, 11:53 AM

#

"MAXPOSITIONERRORSQUARED" is actually not important if you set the "bIgnoreClientMovementErrorChecksAndCorrection " to true

#

It's check in the function that doesn't get reached

#

📎 unknown.png

jolly siren May 10, 2019, 11:54 AM

#

right, we only set bIgnoreClientMovementErrorChecksAndCorrection to true for short durations though, while performing lunges

thin stratus May 10, 2019, 11:54 AM

#

Very well

#

void AGameNetworkManager::StandbyCheatDetected(EStandbyType StandbyType) {}
What is a StandbyCheat?

grizzled stirrup May 10, 2019, 11:54 AM

#

Got it! Would it work in this case if I want my entire game to allow clientside movement? Testing now

#

Really appreciate the help

thin stratus May 10, 2019, 11:54 AM

#

It should

jolly siren May 10, 2019, 11:54 AM

#

yeah it will

grizzled stirrup May 10, 2019, 11:55 AM

#

Incredible

thin stratus May 10, 2019, 11:55 AM

#

It basically 1. cancels the correction and 2. override the location and all important data on the server with what the client has

#

if (GetDefault<AGameNetworkManager>()->ClientAuthorativePosition)
{
    const FVector LocDiff = UpdatedComponent->GetComponentLocation() - ClientLoc; //-V595
    if (!LocDiff.IsZero() || ClientMovementMode != PackNetworkMovementMode() || GetMovementBase() != ClientMovementBase || (CharacterOwner && CharacterOwner->GetBasedMovement().BoneName != ClientBaseBoneName))
    {
        // Just set the position. On subsequent moves we will resolve initially overlapping conditions.
        UpdatedComponent->SetWorldLocation(ClientLoc, false); //-V595

        // Trust the client's movement mode.
        ApplyNetworkMovementMode(ClientMovementMode);

        // Update base and floor at new location.
        SetBase(ClientMovementBase, ClientBaseBoneName);
        UpdateFloorFromAdjustment();

        // Even if base has not changed, we need to recompute the relative offsets (since we've moved).
        SaveBaseLocation();

        LastUpdateLocation = UpdatedComponent ? UpdatedComponent->GetComponentLocation() : FVector::ZeroVector;
        LastUpdateRotation = UpdatedComponent ? UpdatedComponent->GetComponentQuat() : FQuat::Identity;
        LastUpdateVelocity = Velocity;
    }
}

grizzled stirrup May 10, 2019, 11:55 AM

#

And still replicates that new location to other clients as usual?

#

So they simulate etc. locally

thin stratus May 10, 2019, 11:55 AM

#

Yop

jolly siren May 10, 2019, 11:55 AM

#

yes, the move system still works the same

grizzled stirrup May 10, 2019, 11:56 AM

#

This is genuinely so exciting hahah

thin stratus May 10, 2019, 11:56 AM

#

The Simulated stuff is a bit more tricky

#

It uses Character functions

grizzled stirrup May 10, 2019, 11:56 AM

#

As long as the land delegate triggers and it still has access to speed, I'm happy

thin stratus May 10, 2019, 11:57 AM

#

ACharacter::PreNetReceive, ACharacter::PostNetReceive, ACharacter::OnRep_ReplicatedBaseMovement, ACharacter::OnUpdateSimulatedPosition, ACharacter::PostNetReceiveLocationAndRotation

#

And all kinds of shit

#

Took me a bit to get my custom movement to do the same

#

But yeah, Simulated Clients basically get a lot of stuff replicated

#

And perform the rest themselves

#

It uses the default Actor Location and Rotation replication

#

And plugs in the Smoothing Code of the CMC between that

grizzled stirrup May 10, 2019, 11:59 AM

#

So cool thanks for the info

#

Compiling now can't wait to see if it works

thin stratus May 10, 2019, 11:59 AM

#

I wonder if you'd see much difference though

#

Cause in the end, ServerAuthoritive movement also looks good on PIE :D

grizzled stirrup May 10, 2019, 12:00 PM

#

Yeah in PIE but with net pktlag anywhere over 50 it can fall apart

#

When launching at high speeds

thin stratus May 10, 2019, 12:00 PM

#

True

grizzled stirrup May 10, 2019, 12:01 PM

#

Out of curiosity, how do games like Fortnite handle such a case?

thin stratus May 10, 2019, 12:01 PM

#

Better netcode than what we get

grizzled stirrup May 10, 2019, 12:01 PM

#

I assume any kind of client launch that is triggered locally with latency before the server triggers it will create a big difference in server / client and get snapped back

#

Haha yeah true

thin stratus May 10, 2019, 12:01 PM

#

Launching the Client is actually not the problem

#

As long as it's similar to how jumping works

#

We have an ability that "launches" you downwards

#

Doesn't lag at all cause it's handled like jumping

#

Just downwards

#

It gets a bit tricky if two actors collide

#

BUT, even for that you have some CMC functions you can override to handle forces applied then

#

You just can't apply forces outside of that

#

cause that will indeed correct you

grizzled stirrup May 10, 2019, 12:04 PM

#

Ah interesting- the main thing that stuck out to me was that the client would be so far apart from the server version if launching rapidly somewhere that the server would erroneously correct it because of the threshold, but I haven't fully understood / looked into it. Using the standard Launch Character

#

It does works nicely for cases where you are doing a single slowish launch in a single direction, but just gets very frustrating as a client otherwise

#

Btw just tested the code you and Erebel sent- seems to work amazingly well other than a few camera shakes I have going off at wrong times for some reason

#

It seems to even work just using the .ini setting (commenting out bIgnoreClientMovementErrorChecksAndCorrection in the Character constructor)

#

I assume that bool is more used to re-enable server correction in the case where you DO want server authority after a fast launch for example?

#

So useful though thank you both SO much for this help

vernal hollow May 10, 2019, 12:18 PM

#

I did some more testing and found out that my rotation is only jittery on the client when Replicate Movement is set to true on my character

grizzled stirrup May 10, 2019, 12:19 PM

#

Yeah unfortunately clients viewed from the perspective of listen server hosts don't seem to have ANY interpolation AND only update their anim on each network update

#

It was nice to get rid of it on my hacky send RPC with client loc / rot and interp locally vs using the CMC, but there are a few reasons it appears to be done, mainly to keep things in sync

#

Unless you mean your client itself experiences the jitter, in that case it may be a mismatch of values from the server to the client

vernal hollow May 10, 2019, 12:24 PM

#

yeah the client experiences the jitter but i'm not certain why exactly

#

this is what I have running in my characters tick function

#

void AHCharacter::Tick(float DeltaTime)
{
    Super::Tick(DeltaTime);

    if (GetCharacterMovement()->Velocity.Size() > 150)
    {
        FRotator VelocityRotation = GetCharacterMovement()->Velocity.Rotation();

        if (bMovingBackwards)
        {
            VelocityRotation.Add(0, -180, 0);
            //RotateSpeed = RotateSpeed * 0.5f;
        }

        FRotator EndRotation = FMath::RInterpTo(GetActorRotation(), VelocityRotation, DeltaTime, RotateSpeed);
        SetActorRotation(FRotator(0, EndRotation.Yaw, 0));
    }
}

grizzled stirrup May 10, 2019, 12:27 PM

#

I'm assuming the culprit is that the server has a different value to the client and it is constantly being corrected slightly

vernal hollow May 10, 2019, 12:29 PM

#

that was i was thinking, but i'm not sure how to get the client to ignore the servers value without disabling movement replication entirely

grizzled stirrup May 10, 2019, 2:03 PM

#

Anyone have tips for testing with latency through steam locally in the same workspace on multiple computers?

#

I tried connecting with a VPN in Australia and while it does seem to use the australian connection for the steam beacon part (joining the lobby), it weirdly seems to use the real local connection when joining the map

#

This makes it quite hard to test genuine laggy conditions (excluding Net Pktlag = 200 etc.)

twin juniper May 10, 2019, 2:12 PM

#

How do i change port on the listen server and port on the join server thing?

#

Using the "Open level" with "listen" option. And execute console command

bitter oriole May 10, 2019, 2:16 PM

#

@grizzled stirrup NetPktLag is fine tbh

worthy perch May 10, 2019, 2:16 PM

#

You can try using Clumsy to do some network testing.

#

I don't remember what exactly was said and I can't find the post, but I do recall someone saying that NetPktLag isn't entirely accurate.

bitter oriole May 10, 2019, 2:19 PM

#

Of course it's not very accurate. It's just a debug tool, and real latency behaves in a more interesting manner

#

It's still a pretty great tool

#

The net packet burst is pretty cool too

grizzled stirrup May 10, 2019, 2:39 PM

#

Ok cool thanks!!

grizzled stirrup May 10, 2019, 4:08 PM

#

Weird, Clumsy also doesn't have any effect when joining the actual listen server

#

It does in the lobby

#

Very confusing how steam bypasses it somehow and knows it's a local connection

median elbow May 10, 2019, 4:57 PM

#

i'm having a problem with joining a steam lobby session

#

the join works just fine after an invite accepted, but its like not joining the server or something

#

when the lobby host starts a match on another server, they both jump to that server though

#

so the join lobby session is working, its just like not connecting to the server or something

#

i'm trying to get onpostlogin, but its not being called after a join session

#

anybody have any idea why that might be happening?

winged badger May 10, 2019, 7:55 PM

#

steam lobby has no real relations with sessions or unreal networking

#

you don't have to be connected via unreal server to be connected via steam lobby

#

and you can connect to unreal server via steam without being connected to the lobby

#

im guessing you're mixing up lobby and session

grizzled stirrup May 10, 2019, 10:27 PM

#

@jolly siren Thank you so much for the client authority movement tips earlier, it's working amazingly well. The only issue I've encountered so far is if a group of enemy characters surround a high ping client on the server, and on his screen he is jumping / running away from them he DOES get corrected back to be trapped between the enemy collision. Is this intended behavior? I guess it makes sense, the server trusts the client authority until it is physically blocked by another networked entity on the serverside

#

To be clear I have bIgnoreClientMovementErrorChecksAndCorrection set to true always

jolly siren May 10, 2019, 10:36 PM

#

I found that bIgnoreClientMovementErrorChecksAndCorrection wasn't setup perfectly ootb

#

And had to do the following

#

void UFooCharMovementComponent::ClientAdjustPosition_Implementation(float TimeStamp, FVector NewLoc, FVector NewVel, UPrimitiveComponent* NewBase, FName NewBaseBoneName, bool bHasBase, bool bBaseRelativePosition, uint8 ServerMovementMode) {
    if (!bIgnoreClientMovementErrorChecksAndCorrection) {
        Super::ClientAdjustPosition_Implementation(TimeStamp, NewLoc, NewVel, NewBase, NewBaseBoneName, bHasBase, bBaseRelativePosition, ServerMovementMode);
    }
}

#

I would try something like that and see how it behaves

grizzled stirrup May 10, 2019, 10:37 PM

#

Perfect thank you so much

#

I don't need a source build for this correct? I just need to make my own CMC and override that function as shown?

jolly siren May 10, 2019, 10:37 PM

#

correct

grizzled stirrup May 10, 2019, 10:37 PM

#

Great will let you know how it goes! This has been a gamechanger for my project

#

SO much better than interpolating raw position

#

From the client

#

Looks 1000x better for other clients

jolly siren May 10, 2019, 10:38 PM

#

Glad to hear it, hopefully that helps 😃

#

Are you making a competitive game?

grizzled stirrup May 10, 2019, 10:40 PM

#

Only competitive in the sense that you and your friend are battling for a higher score against enemies

#

Not PvP

#

I want both players to have the same smooth experience regardless of ping

#

Instead of the host having a big advantage

jolly siren May 10, 2019, 10:41 PM

#

ahh okay nice, yeah that is a lot easier. Much simpler in non PvP worlds

grizzled stirrup May 10, 2019, 10:41 PM

#

Cheating would only affect a single listen server lobby as opposed to anything bigger

#

Yep gave up on my PvP dreams a long while ago 😄

#

Though this should be still possible to have fun PvP with friends if they want

#

Just would be a nightmare in any kind of public lobbies

jolly siren May 10, 2019, 10:48 PM

#

Right, yeah I was just going to give the normal spiel about how this is dangerous in PvP environments

grizzled stirrup May 10, 2019, 10:58 PM

#

When overriding that function since it's a client RPC, do I only override ClientAdjustPosition_Implementation in the header and not ClientAdjustPosition?

#

I see the RPCs are set up a bit differently to normal classes

#

Or should I override both in the header?

#

/** Replicate position correction to client, associated with a timestamped servermove. Client will replay subsequent moves after applying adjustment. */ virtual void ClientAdjustPosition(float TimeStamp, FVector NewLoc, FVector NewVel, UPrimitiveComponent* NewBase, FName NewBaseBoneName, bool bHasBase, bool bBaseRelativePosition, uint8 ServerMovementMode); virtual void ClientAdjustPosition_Implementation(float TimeStamp, FVector NewLoc, FVector NewVel, UPrimitiveComponent* NewBase, FName NewBaseBoneName, bool bHasBase, bool bBaseRelativePosition, uint8 ServerMovementMode);

jolly siren May 10, 2019, 11:01 PM

#

Just the implementation

#

virtual void ClientAdjustPosition_Implementation(float TimeStamp, FVector NewLoc, FVector NewVel, UPrimitiveComponent* NewBase, FName NewBaseBoneName, bool bHasBase, bool bBaseRelativePosition, uint8 ServerMovementMode) override;

grizzled stirrup May 10, 2019, 11:01 PM

#

Great thanks so much!!

jolly siren May 10, 2019, 11:01 PM

#

np

grizzled stirrup May 10, 2019, 11:13 PM

#

@jolly siren Just tested the same scenarios and it appears to work PERFECTLY

#

Can't thank you enough

#

I put in a logtemp on that override and it is called exactly when I was noticing the corrections before

#

Only slight difference from using the stock CMC is that I'm now seeing this LogCharacterMovement spammed in the logs during these events (when many enemies are grouped up around the player and don't have space to move) LogCharacterMovement: BP_EnemyC_C_0 is stuck and failed to move! Velocity: X=514.63... etc

#

Do you know if deriving from CMC makes certain logs print that normally would be hidden?

jolly siren May 10, 2019, 11:16 PM

#

Hm I wouldn't expect it to affect logging

grizzled stirrup May 10, 2019, 11:16 PM

#

Ah yeah scratch that actually it was happening since I started using the setup you mentioned earlier

#

My bad

#

Just checked old logs from earlier

#

Working like a charm now, really appreciate the help

#

Now to try and give the clients some kind of interpolation when being viewed from the listen server 😄

#

So I can get away with a lower than usual update rate

jolly siren May 10, 2019, 11:18 PM

#

Awesome, glad I could help 😃

grizzled stirrup May 10, 2019, 11:18 PM

#

There would be a ZERO percent chance I could have figured those steps out alone

#

So little info on these specifics online

grizzled stirrup May 11, 2019, 1:29 AM

#

Interestingly I have found that when viewing a listen server client as the listen server host with Slomo 0.2 command enabled, while there is NO interpolation of movement between network updates while the client is jumping for example, if I hold input on the client (so holding W while jumping), the interpolation is buttery smooth on the listen server

#

I wonder if there is a way I can get it to always run that codepath when the client is sending input, to get proper smoothing / interpolation, as the CMC seems to be set up to have correct smoothing, but perhaps it's just a bug that has existed a long time (that listen server hosts see clients with no interp between net updates)

#

Ah it seems p.NetEnableMoveCombining 0 does exactly this

jolly siren May 11, 2019, 1:43 AM

#

ah yeah that will be much more expensive on the network

#

with move combining disabled

grizzled stirrup May 11, 2019, 1:44 AM

#

Would you say it's acceptable to run only on client characters in a 2-4 player co-op game? It's really only to try and make clients look smooth from the perspective of the listen server

#

It works fine the other way around or clients seeing other clients

#

There's just 0 interp on the listen server's view of the client it seems by default

#

Ah I guess you can't set it individually- since it's a console command it'd affect ALL characters which is a big waste

#

Unless it doesn't factor in AI character input which is what the other characters would be

jolly siren May 11, 2019, 1:45 AM

#

AI movement just runs on the server. It doesn't need to be sent from client to server, like with normal players

#

But yeah with low player count it should be okay

#

You can also tweak the values if you don't want to turn it completely off

#

ClientNetSendMoveDeltaTime=0.0333
ClientNetSendMoveDeltaTimeThrottled=0.0444
ClientNetSendMoveDeltaTimeStationary=0.0333

grizzled stirrup May 11, 2019, 1:46 AM

#

Oh that's amazing

#

So with p.NetEnableMoveCombining 0 it'd send every frame?

#

But this allows you to specify the freq

#

So like 0.01 or whatever

jolly siren May 11, 2019, 1:46 AM

#

Yeah then you can just tweak them until you get the smoothness you want and still get some savings

grizzled stirrup May 11, 2019, 1:47 AM

#

That's much cleaner! Plus I can make sure it only affects my human characters

jolly siren May 11, 2019, 1:47 AM

#

😃

grizzled stirrup May 11, 2019, 1:47 AM

#

You are unbelievably helpful haha

#

This is amazing

jolly siren May 11, 2019, 1:47 AM

#

no problem 💪

grizzled stirrup May 11, 2019, 2:36 AM

#

I feel your pain, it is quite annoying- BP's will register the change to the default value but won't change the value itself

#

Especially with HotReload you often have to recreate BP's unless closing the editor and making sure you compile without it open

meager spade May 11, 2019, 10:54 AM

#

my turn in place causes jitter and i cant work out why 😦

wet tangle May 11, 2019, 11:16 AM

#

If my project uses steam and hosts lan it can only work on differentr computers right?

bitter oriole May 11, 2019, 11:16 AM

#

Steam is unrelated to hosting

#

But yeah, you can't have two Steam users on the same machine

wet tangle May 11, 2019, 11:29 AM

#

ty

wanton pebble May 11, 2019, 12:30 PM

#

quick question

#

how do i replicate aa variable in C++?

#

basically i have a crouch variable that i'm trying to replicate

#

but using DoRepLifetime doesn't help

bitter oriole May 11, 2019, 12:31 PM

#

Depends on whether you want client to server or server to client

wanton pebble May 11, 2019, 12:34 PM

#

it's just a crouch... i'm not sure what that would necessitate

bitter oriole May 11, 2019, 12:35 PM

#

There is no such thing as "just replicate X"

grizzled stirrup May 11, 2019, 12:35 PM

#

Client to server in that case as you'd want the client to instigate the event.

bitter oriole May 11, 2019, 12:35 PM

#

Both, really

#

RPC from client to server, replictaed var from server to other clients, marked as "all but owner"

grizzled stirrup May 11, 2019, 12:35 PM

#

True!

#

You'd use RepNotify in this case correct?

#

Since it'd trigger the crouch on proxies

bitter oriole May 11, 2019, 12:36 PM

#

Depends on a lot of factors.

wanton pebble May 11, 2019, 12:41 PM

#

void ASCharacter::ExecCrouch()
{
        if (CrouchToggle == false)
        {
            if (IsSprinting == true)
            {
                IsSprinting = false;
            }
            IsCrouching = true;
            CrouchToggle = true;
            SpeedMultiplier = 3.0f;
        }
        else
        {
            IsCrouching = false;
            CrouchToggle = false;
            SpeedMultiplier = 1.0f;
        }
}```

#

here's my crouch code

#

    float TargetHalfHeight = IsCrouching? CrouchedCapsuleHalfHeight : DefaultCapsuleHalfHeight;

    float NewHalfHeight = FMath::FInterpTo(GetCapsuleComponent()->GetScaledCapsuleHalfHeight(), TargetHalfHeight, DeltaTime, CrouchSpeed);

    GetCapsuleComponent()->SetCapsuleHalfHeight(NewHalfHeight);
    //```

#

and here's the code within tick

#

currently all i'm doing is this

#

{
    Super::GetLifetimeReplicatedProps(OutLifetimeProps);

    DOREPLIFETIME(ASCharacter, IsCrouching);
}```

grizzled stirrup May 11, 2019, 12:41 PM

#

You have to send IsCrouching to the server via a Server RPC

#

Right now it's only local

wanton pebble May 11, 2019, 12:41 PM

#

    bool IsCrouching;```

#

and here's the variable

#

how would i do that?

grizzled stirrup May 11, 2019, 12:42 PM

#

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

#

In the .h

wanton pebble May 11, 2019, 12:43 PM

#

and then an implementation and validate in the cpp file?

grizzled stirrup May 11, 2019, 12:43 PM

#

Yep

#

So basically when you run your local crouch code first check if authority

wanton pebble May 11, 2019, 12:43 PM

#

i didn't know that was called Server RPC, thanks

grizzled stirrup May 11, 2019, 12:43 PM

#

If not authority run ServerSetIsCrouching

#

But ALSO run it locally

wanton pebble May 11, 2019, 12:43 PM

#

so if(Role == ROLE_Authority)

grizzled stirrup May 11, 2019, 12:43 PM

#

Then make sure you have COND_SkipOwner on IsCrouching so the client won't trigger the crouch twice when the server replicates it

#

Do this

#

if (Role < ROLE_Authority) { ServerSetIsCrouching(); }

wanton pebble May 11, 2019, 12:44 PM

#

roger that, thanks

grizzled stirrup May 11, 2019, 12:44 PM

#

Btw how do you do the nice code snippet?

#

Within the bubble

#

On discord

solar stirrup May 11, 2019, 12:46 PM

#

```cpp
// your code
```

#

` these ticks not ' these

grizzled stirrup May 11, 2019, 12:48 PM

#

Ah perfect thanks a lot

wanton pebble May 11, 2019, 1:21 PM

#

@grizzled stirrup cheers man, that worked!

twin juniper May 11, 2019, 3:15 PM

#

Hey, anybody knows why Multiplayer won't work sometimes? its just randomly, sometimes it works for me and sometimes it doesn't :/

jolly siren May 11, 2019, 3:40 PM

#

Does anyone know of a good way to optimize bot cmc movement on the client?

#

📎 unknown.png

grave kayak May 11, 2019, 3:43 PM

#

use simpler collision shape(s), judging from that profile

bitter oriole May 11, 2019, 3:44 PM

#

@jolly siren Do you have many components on that pawn ?

jolly siren May 11, 2019, 3:46 PM

#

Sure, there are a bunch of meshes, spring arm, camera, sound stuff, etc

#

But yeah it looks like overlaps is the most expensive

#

I mostly just use overlap events for picking up weapons, items, etc

grave kayak May 11, 2019, 3:51 PM

#

i dont know how precise your collision has to be, but as a quick test you can disable collision on the skeletal mesh and add a capsule primitive and use that to get the overlap events

jolly siren May 11, 2019, 3:52 PM

#

oh I thought that is what these overlaps were from. I'll check the mesh now

twin juniper May 11, 2019, 3:54 PM

#

So from what I noticed, if you launch the MP game on the same computer twice, it will recognize as only one player.
The third launch will work as a second player, and it shouldnt be a problem because nobody runs the game twice on the same PC and plays like that, but for testing purposes, that's the solution.

jolly siren May 11, 2019, 4:08 PM

#

@grave kayak That helped a ton, thank you 😃

grave kayak May 11, 2019, 4:10 PM

#

no problem 😃

worn nymph May 11, 2019, 4:33 PM

#

anybody here good with collisions? i am trying to spawn an object (in this case a portal) at the end of a line trace where it hits something. The issue is the object is spawning in the ground or in the walls etc
i tried giving it a really big collision shape and setting the spawn setting to adjust location if colliding but that makes no difference

📎 unknown.png

rotund sapphire May 11, 2019, 4:39 PM

#

@worn nymph It's not quite a multiplayer related question. You must include the mesh bounds in your calculations when you position the new mesh. The end of the line trace is hitting the object's surface, you obviously can't put an object there, since the new mesh's pivot is not on the 'back' of the new mesh but in the middle of it.

rotund sapphire May 11, 2019, 4:55 PM

#

Try a sweep trace with the bounds of the mesh, so you can avoid clipping

twin minnow May 11, 2019, 5:05 PM

#

I experienced something similar, @worn nymph are you calling spawnactor in a server rpc?

twin juniper May 11, 2019, 5:21 PM

#

Is all the player controllers the same on a listen server?

#

the destroy actor when they have 0 health only works on the server character

winged badger May 11, 2019, 5:22 PM

#

you should really read the compendium (again?)

rotund sapphire May 11, 2019, 5:25 PM

#

The getplayercontroller(0) is an awful bad practice and i see it blueprints too many time. Instead, Pawn->GetController->Cast to PC-> there is your PC to work with

fleet raven May 11, 2019, 5:25 PM

#

it could have been so much easier on new users, if that function was get local player controller and simply did nothing on server

winged badger May 11, 2019, 5:25 PM

#

it is very likely he is trying to destroy the Pawn in that reference chain Robart

twin juniper May 11, 2019, 5:26 PM

#

Currently i am casting to BP_Character and get controlled pawn then player controller. Then i destroy the bp_character actor if it has below 0 health

#

problem is

#

if i shoot enemy

#

always the server client dies

winged badger May 11, 2019, 5:27 PM

#

so you start with a reference to a Pawn you want to destroy, then do a Cast you don't need, then do other crazy stuff just to get a reference you started with?

twin juniper May 11, 2019, 5:27 PM

#

I am doing all of this in player controller blueprint

winged badger May 11, 2019, 5:28 PM

#

yikes

#

if you shot it, you have a refence to it

#

if you modified its health you have a reference to it

#

why do you need a roundabout way to get it to destroy it?

#

and worse, triggering the destruction/cleanup should be atomic with modifying health, if it ends up modified to <= 0

twin juniper May 11, 2019, 5:48 PM

#

Also

#

i just tested a new game

#

with friends

#

my friend tells me i keep teleporting for him around the map

#

we both have extremely good internet

#

he has 1gb internet speed

#

i have 100mb internet speed

grizzled stirrup May 11, 2019, 6:10 PM

#

Is Net PktLag=200 actually simulating 400 ms ping?

#

Or 200 ms

bitter oriole May 11, 2019, 6:12 PM

#

400ms ping

grizzled stirrup May 11, 2019, 6:13 PM

#

Oh fantastic, was testing with Net PktLag=500 for extreme conditions and it felt way too delayed

#

Thanks!

#

Will tone it back to around 100 / 150 for worst case scenarios

fleet raven May 11, 2019, 6:14 PM

#

it will delay outgoing packets on the side you enter it

#

so to make 400ms ping, you must type that command on both the client and server

grizzled stirrup May 11, 2019, 6:15 PM

#

I called it from the level BP so it should affect both

#

So this delays the client sending the action by 200ms and then the servers response by 200 right?

fleet raven May 11, 2019, 6:15 PM

#

ye

grizzled stirrup May 11, 2019, 6:15 PM

#

thanks

fleet raven May 11, 2019, 6:15 PM

#

having it on both sides is the most realistic way

#

also turn on the lag variance and packet loss

grizzled stirrup May 11, 2019, 6:16 PM

#

Net PktLoss is the only one that seems to mess everything up horribly

#

But it does that too in other games when I play without a modem!

#

Will do

fleet raven May 11, 2019, 6:16 PM

#

if that messes you up horribly, the game will not work on real networks

#

usually caused by people using unreliable rpcs in places they shouldn't

grizzled stirrup May 11, 2019, 6:17 PM

#

Well horribly as in it misses updates and everything gets rubberbanded to the correct position

#

I'm assuming a realistic number for the command for packet loss is like 5?