Convert to vanilla UE4

Created by William Joseph
Dec 22, 2020

As .umap and .uasset files saved in Enlighten UE4 contain Enlighten-specific data, you can only use them with Enlighten UE4. To load these files in the vanilla UE4 distribution, you can back up and remove the Enlighten-specific data.

This is useful for:

  • verifying whether certain behavior is specific to Enlighten, or also occurs in vanilla UE4
  • reporting bugs in vanilla UE4 to Epic and provide them with assets to replicate the problem

Remove Enlighten-specific data

To remove Enlighten-specific data, use the EnlightenStripEnlightenData commandlet. The commandlet modifies the assets that the chosen asset depends on. It doesn't modify dependent assets in the Engine content folder.

<editor executable> <project name> -run=EnlightenStripEnlightenData <chosen asset file> [-AutoCheckOutPackages]

Parameters:

  • <editor executable>

    This is the path path to your UE4 executable.

  • <project name>

    The first command line argument to UE4 is always the path to the project file containing the assets.

  • -run=EnlightenStripEnlightenData

    This is the commandlet that tells UE4 to remove the Enlighten-specific data.

  • <chosen asset file>

    This argument to the above commandlet is the asset file to operate on. Use the full path to either a .umap or .uasset file.

  • [-AutoCheckOutPackages]

If the assets are read-only because the project is configured to use Perforce, the EnlightenStripEnlightenData commandlet reports an error. Either make the asset files writable on disk, or specify the optional -AutoCheckOutPackages argument.


The following example command removes Enlighten-specific data from MyProject/Content/Maps/MyLevel.umap and all assets it depends on. If Perforce is configured for the project, the assets are automatically added to the default pending changelist.

 UE4Editor.exe MyProject -run=EnlightenStripEnlightenData /Game/Maps/MyLevel -AutoCheckOutPackages

This command modifies the asset files on disk. To avoid losing data, make sure you have a backup of the project content before using this command.

Create a streamlined project

The commandlet removes all references to Enlighten-specific data from the chosen asset file and dependent assets. This might leave unused empty .uasset files that previously contained Enlighten precompute data.

To remove all Enlighten-specific data or asset files:

  1. Make sure you have a backup of the project.
  2. Make all assets writable on disk.
  3. Run the commandlet for the chosen asset using the Enlighten UE4 editor build.
  4. Open the project in the vanilla UE4 editor build.
  5. In the content browser, Migrate the chosen asset to a new empty project.

The resulting project contains only the files that the chosen asset depends on, and can be loaded in the vanilla UE4 editor.