Documentation Localization Tools

Instructions on how to use the provided tools for localizing documentation.


The documentation localization tools provide a fast and robust localization process, which can save a lot of time wasted in detecting, previewing, checking in and out the documents that have been added or updated. This, in turn, increases the overall quality of the localization of the documentation.


  • ActivePerl:

  • Araxis Merge (installed to C:\Program Files\Araxis\Araxis Merge. Otherwise, you may need to edit diffrev3.bat and makenew.bat accordingly)

  • P4V

  • MS Excel

Setting up the Tools

The localization tools are located at:


Make sure you have this folder synced.

The tools are currently set up for localizing to Korean. To make this script work for other languages other than KOR, you may need to edit with notepad and use Find & Replace (Ctrl + H) to replace all occurrences of KOR with another language code (i.e. CHN, JPN, etc.)

You may also need to set the right path for UnrealDocTool.exe in diffrev3.bat and makenew.bat. It should point to UE4\Engine\Binaries\DotNET\UnrealDocTool.exe in your build on your local drive.

As of ChangeList# 1418681 (19th Oct. 2012), the process for detecting updates has been updated to compare not only CL# but also the INTSourceChangelist metadata in the .udn files. This value indicates the CL# of the INT that the localized file is based on. This eliminates the need to check the history manually before you submit your translations, which is more convenient and robust as well.


To use the localization tools, make a shortcut for diffstart.bat on your desktop and run it. This will perform the following operations:

  • Sync //depot/UE4/Engine/Documentation/ to the head revision

  • Run and log its output to [Current Date].csv

  • Run the cmd console and the [Current Date].csv

The CSV file (example shown below) displays which files need attention and what actions to take on each.


  • Column A displays the status of the localized file, which can be one of the following: OUTDATED , MISSING , and DELETED .

  • Column B is the cmd line that you need to run to resolve it. You can just copy this cell and paste it into the cmd console (it also works for multiple rows).

If you enable Fast Edit Mode In the properties of the cmd console, you can paste with just simple right-click.

After the appropriate actions have been taken and the localized files are updated locally,

Outdated Files

A value of OUTDATED in Column A means the INT that this KOR is based on has been updated. To update the localized file, the diffrev3.bat file is used.

Executing diffrev3.bat performs the following:

* Run Araxis Merge in 3 way diff mode in the order of: New INT - Old INT (temp file) - 
Localized file (CHN, JPN, KOR, etc.)
* Checks out the localized file
* Launch the browser to preview New INT for reference.

After running diffrev3.bat, edit the localized file by adding or modifying translations for any new or changed text.

Make sure to update INTSourceChangelist in the localized file (right) to match the one in Old INT (center), which is actually the CL# of New INT (left). Note that the tag is not in the actual New INT file itself. You can just update the localized file (right) and save it (Ctrl+S).

In case you need to edit the INT file as well (i.e. to correct typos, etc.), you can easily check that out by clicking [...] button to the right of the filename field and then right clicking on the INT.udn in the file browser that appears and choosing Perforce > Check Out.

Also, you can set up to preview any source you are working with by copying "SendTo\nConvert to HTML.bat"
to C:\Users[UserName]\AppData\Roaming\Microsoft\Windows\SendTo. Afterwards, you can preview any .udn by right-clicking on it and choosing Send To > nConvert to HTML.bat (RMB > N > N).

These instructions are for Windows 7. The location will differ depending on your operating system.

Missing Files

A value of MISSING in Column A means there is no matching localized file for an existing INT.udn file.

Executing makenew.bat performs the following:

  • Create a new localized file by copying the existing INT.udn file.

  • Open both the INT.udn (left) and localized (right) files in Araxis Merge.

  • Check out the localized file.

  • Launch the browser to preview the existing INT.udn file.

After running makenew.bat, edit the localized file by translating its contents to the target language.

Deleted Files

A value of DELETED in Column A means the INT.udn file that the localized file is based on has been deleted. All you need for these files is copy and paste the command from Column B into the cmd console.

Submitting Changes

Submit all the modified files to P4 with a description for the changelist. The description should give a brief overview of the changes. In the event that you edited any INT files, make note of that as well.

An example of simply updating localization files:

#loc UE4DocKor updates

Example containing edits to INT files as well:

#loc UE4DocKor updates

- fixed typos in INT
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