World Partition Map: Everything dissapearing when changing Map's name

Hello everyone,

CAUTION: PLEASE DON’T TRY THIS ON YOUR OWN PRODUCTION PROJECT!

I don’t know if it’s a bug or intended to work this way (I don’t think so), but everytime I change a World Parition Map’s name, the map become empty (as if every actor has been deleted) and only a single “Brush” actor remain (that I never added in the first place).

Is someone aware of this issue and know a way to bring actors back? Is it a bug or the way World Composition is meant to be?

Thanks in advance!

Are you renaming the map from withing the editor? Or just renaming the file in Windows (if so, don’t do that). There is an __ExternalActors__ folder in your Content folder that keeps the ‘One File Per Actor’ data. There will be folder(s) in that __ExternalActors__ folder that matches the folder and filename where your original .umap file is located. Changing the map name outside of the editor prevents it from being able to find the One File Per Actor data later becase the new map name and old __ExternalActors__ folder name no longer matches.

The biggest issue here is that I change it from within the editor!
I see the ExternalActors Folder and every previous map name, with a bunch of empty folders and, sometimes, a uasset file.

However, I can’t use them anymore (or I don’t know how to), and reverting back to the old name doesn’t solve the issue, as far as I checked!
I don’t really understand what’s going on here, so I’m starting to be afraid of losing my maps!

Ah… I found a WorldPartitionRenameCommandlet which is apparently what you are supposed to use to rename a partitioned world. You run it as you would other commandlets (from a Windows Command Prompt window)…

UnrealEditor.exe <full_path_to_project_name> -run=WorldPartitionRenameCommandlet -AllowCommandletRendering -oldmap=<old_map_name> -newmap=<full_path_to_new_map_name>

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