[Twitch] Networking, and Game Jam Theme Announce! - Nov 13, 2014 @ 2PM ET

If making a networked game with Blueprints, whats the fastest way to check if networking and replication is working correctly for late joiners?

I just wanted to second this question! I think these days players just can’t be expected anymore to enter an IP adress to be able to join a game.
So since making MP games easier/possible with only BPs is a topic, I would like to hear if there are any plans to add BP nodes that can create servers and output a list of available servers?
This could be as simple or complex as you want to make it, as long as it’s not necessary to use C++ to get a list of available (local or even better web) servers for the player to connect to.

Nice… The networking model isn’t exactly intuitive nor easy to get a new developers head around. You guys have a lot to cover for a single broadcast!

{Edit} Thinking about it a bit more, I’d like to hear a discussion on planning networking from a design-first perspective (top down), how to predict performance (& manage performance expectations), and debugging strategies.

From my (very limited) experience, and IMHO, networking seems to be a bit of a ad-hoc thing that tends towards a “try it, if it seems to work then it works” approach that can be deadline-problematic…

Are there any plans to move the sexy network voodoo out of CharacterMovementComponent so we can use them in Pawn derived classes?

If not, I would love a tutorial going over how this component works so we can replicate it on our own.

Can you give any indication when networking will be supported in HTML5 games?

Could you please eloborate on how to replicate data per connection and not per actor?

I mean as of today, if you set COND_CUSTOM, you can manage per actor the replication of the variable but you have no access to the scope of it (connection).

Let’s say you want a replication to only happen for the owner (COND_OWNER) but you want to manage it (COND_CUSTOM)… as of today, I didn’t find a way to do it.
More, let’s say that I want to send the actor life to all his teammates, today replication system doesn’t seems to manage that case.

Can we we some insight on this on how to manage those cases? Is there any plan to manage this in the future?


Any plans for making UObject multi threading easier ? (like creating, destroying, communicating between UObjects over separate threads).

Another question. Is replication multi threaded or everything is just done by single thread ? This is another area which could probably benefit most from multi threading, especially with huge amount of replicated actors and properties on them. (bandwidth aside).

It would benefit everyone but probably server most, where they are not really limited by performance of other systems (like graphics).

I can’t follow the stream live because of timezones, but I do have generic questions I hope to get answers of.

  1. Replicated Timeline based elevators (such as elevators used in UT) don’t work properly, is there any progress on this?

  2. Does the Online Subsystem notifies the steam ‘master server list’ when a dedicated server has booted?
    If not, could we get more details about it on the Steam online subsystem help page to make it work (there is nothing about it on steam documentation and nothing about it on Unreal’s side as well, please help!)?
    (The steam ‘master server list’ allows users to find servers to play on. Additionally the server provide details on what game mode and map is running)

  3. Related to building dedicated server:
    At this moment building a dedicated server fails if you use UMG in your project.
    LogLinker:Warning: Can’t find file ‘/Script/UMGEditor’ LoadErrors: Info Failed to load etc.
    Is this fixed for 4.6? We really hope to release before Christmas.

  4. We made a custom animation node through an additional editor module. It works fine for our clients but its impossible to build our server now. When compiling the server with visual studio the builder tool crashes completely and sais it can’t find unrealed. How can we make custom animation nodes that compile well on dedicated servers?

  5. Related to animations:
    In an animation sequence we are able to trigger sounds on the animation timeline. That’s very convenient but in some cases we need to stop the stound in the middle of the playback. (Ex: you reload your weapon but switch for another weapon before the reload animation is completed). Is there a way to do that cleanly?

  6. And last question just to keep traditions: when do you expect to release 4.6?

Thank you guys and keep up the great work, we love you :slight_smile:


What is the best workflow to trigger “one-shot” montages in a replicated environment, and react to events / branching point events?

As an exemple, I will take a case from the basket ball game I’m developping:

  • A PlayerController pushes a button to make the pawn pass the ball
  • I check if we are on the server. If not, I call Server_Pass. If we are, I call Multicast_Pass
  • In Server_Pass_Implementation, I call Pass, which will then call Multicast_Pass
  • In Multicast_Pass, as it is called on the server and all clients, I play the montage everywhere.
  • I have a branching point in the animation to actually mark the moment the ball should leave the pawn’s hands to be passed to a teammate. I catch this “event” and detach the ball from the character’s hand and do the AddImpulse on the ball. But only on the server, as it is the only one to manage the gameplay. The replication will do the rest.

Is this “ping-pong” between the player who initiated the action and the server the correct way to do this?


One more thing I ran into, more of a potential issue/bug than a question really. But thought I’d raise it to see if it’s a known issue or not:


How do you handle re-spawning the character in say a death match? Also, how would you get the playerstart locations from a map into the gamemode blueprint so you can select one at random?

  • HOW TO REPLICATE PHYSICS BASED MOVEMENT? (tutorial will be appreciated)

Are there any plans to integrate RakNet into UE4’s core or is there a plugin in the works from either Epic Games or the community at large?

If not,
What are the pros and cons of Epic’s own networking code over that of RakNet??? (Oculus LCC purchased RakNet about 5 months ago and made it open-source for those that don’t know)

RakNet Oculus Announcement: http://www.oculus.com/blog/announcing-oculus-connect-raknet-open-source-and-e3-2014-awards/
RakNet GitHub: GitHub - facebookarchive/RakNet: RakNet is a cross platform, open source, C++ networking engine fo

Hey Rje, I have one of my technicians assigned to investigate that question. He’ll get a response to you as soon as he can.

heck , i do not understand how twitch store last video…
Please someone Can giving me the link of the last twitch, I missed it ?
Thank by advance

Oh yes thank you, I found the previous editions button :o

This is excellent news ! Having OSS functionality available through BP will save so many so much time. Thank you ! :slight_smile:

Any word on when the sample game mentioned at 12m 9s will be available? http://youtu.be/4LV7KKtzKs8?t=12m9s


I tried to understand the answer to the question “Could you please eloborate on how to replicate data per connection and not per actor?” but I’m not getting the point on how you will deal that with a array on the playercontroller set to COND_AllButOwner.

Could you please write down in the forum the quick algorithym logic you share on during the video? I’m don’t know how I should can control to whom I’m sending the data.