World Composition breaks multiplayer testing in other levels

When using World Composition, the ability to playtest multiplayer features in other levels breaks. Clients appear in the default game startup map instead of the targeted map. If ServerTravel is used, all clients travel to their own instances of the targeted map.

Steps to reproduce:

  1. Create a new level. Place an object in this level to be able to tell the difference.
  2. Create a new level in another folder intended for world composition. Turn on world composition and origin shifting for this level. Set this map as the game’s default startup map
  3. Switch back to the previous level.
  4. Increase the number of clients from 1 to something higher.
  5. Press play. All clients who are not the server will spawn in the World Composition map. If ServerTravel is used, all clients will appear in their own instances of the targeted map.
  6. If the first level is set as the default startup map, the effect will be the same as if servertravel had been used.
  7. If a dedicated server is used, the effect will be the same (with the main viewport also displaying the behaviour of a client).

Hi Jargon,

I tested this in 4.7.1 and could not reproduce what you have described. Are you using a different engine version? Does this happen in a new project, or only your current project?

This is on 4.7.1, yes. I can reproduce the issue in another project - I created a new First Person Template project and did the steps described above. The issue appears here as well.

Actually, the issue is slightliy different - the characters do end up on the same map right away there, but they are still in different instances of that map and thus cannot see each other.

Welp, sorry for the comment train here. I can’t reproduce the issue as well, and after some fiddling I’ve determined that my other actors aren’t replicating properly. I can’t see the other pawns, and physics-enabled actors in the scene aren’t replicating their movement. Really glitchy shadows are visible from the other pawns, though.

It’s as if replication has broken down across all my levels. This only happens in my project, and not in fresh ones.

That’s okay. If you reset the replication settings on your actors, does it fix the issue in your project?

Unfortunately not. I attempted to set both Replicates and Replicate Movement to off, compiled and played, reset them back to enabled, and the issue was still there.

Let me check with the network devs to see if they know what might be causing that. I’ll let you know if they need more information (logs, etc).

Super, thank you. Might be a good idea to say that I have a number of C++ RPCs that are affected as well.

Was the project upgraded from a previous engine version?

Yes - it’s been upgraded with every version since 4.2 without any issues so far. The latest jump was from 4.6 to 4.7, and then from 4.7 to 4.7.1.

And did this start happening in the move from 4.6.1 to 4.7.0, or from 4.7.0 to 4.7.1?

I apologise, I made a mistake there. The conversion was directly from 4.6 to 4.7.1. That is also where the issue started.

Sorry for the delay in response; a lot of our devs were at GDC this week so I haven’t gotten a solid response yet. I do have one more question, though: world origin shifting doesn’t work in Multiplayer currently, and while it’s on our wishlist it isn’t currently scheduled to be worked on. If you turn that off, do the replication issues cease?

Here’s a link to a forum thread in which our main World Comp developer mentions this:

And another AnswerHub post where elaborates a bit more:

Hey there! Don’t worry about the delay - you’ve had some busy days!

World Origin Rebasing was actually already turned off - I tried enabling it, but that had no effect, unfortunately.

I wouldn’t have a problem with it if it was restricted to the world comp level, but since I can’t test other maps it’s really thrown a wrench in my machinery :frowning:

Heya Jaron,

Can you post the Client/Server logs for us? We want to see if clients are truly connecting to the server, and if there are any warnings related to replication. Thanks!

Sure thing - what files would that specifically be?

It’ll just be your standard log files from your project, located in your Saved\Logs folder. It should include some useful network information. Run the game as you normally do when you see these issues, and then zip and attach the most recent log files here.

Here are the logs:link text
The file contains two runs, both with two clients on a non-world comp map. The first run is without a dedicated server, the second run with.

Hi Jargon,

I apologize, I forgot to mention we’d like you to make sure you have the right logs unsuppressed. In the DefaultEngine.ini file (in the Config folder for your project), add the following and save:


Then run through the game again as normal and get us the most recent logs. Sorry to make you do that again =/