A template for creating RimWorld mods.
RimWorld mods are folders which contain subfolders and files with specific names.
/Aboutcontains meta information about the mod./Assembliescontains C# assemblies for the mod./Defscontains XML files with definitions for each thing added by the mod./Languagescontains translation data for the mod./Patchescontains XML files with modifications to the definitions of things added by other mods./Soundscontains audio files supplied by the mod./Texturescontains image files supplied by the mod.
Starting from a mod's root directory, RimWorld checks a sequence of subfolders in order and loads files from all of them:
/1.5(skipped if any folder above was found)/1.4(skipped if any folder above was found)/1.3(skipped if any folder above was found)/1.2(skipped if any folder above was found)/1.1(skipped if any folder above was found)/1.0(skipped if any folder above was found)/Common(always checked)/(always checked)
If the same file name is present in several of these folders, the first one checked will take precedence and the others will be ignored.
The About folder should always be in the mod's root directory. It cannot differ between game versions.
When sharing files between versions, the Common folder should be used.
To gain finer control over how mod files are loaded, you can make a file called LoadFolders.xml in the mod's root directory. For example:
<?xml version="1.0" encoding="UTF-8" ?>
<loadFolders>
<v1.1>
<li>Common</li>
<li>1.1</li>
</v1.1>
<v1.2>
<li>Common</li>
<li>1.2</li>
<!-- IfModActive and IfModNotActive can contain comma-separated (treated like an OR operator) package IDs of mods. The folder will only be loaded if the condition is met. -->
<li IfModActive="Ludeon.RimWorld.Royalty">RoyaltySpecific</li>
</v1.2>
<v1.3>
<li>Common</li>
<li>1.3</li>
<li IfModActive="Ludeon.RimWorld.Ideology,Ludeon.RimWorld.Royalty">AnyExpansions</li>
<li IfModNotActive="Ludeon.RimWorld.Ideology">NoIdeology</li>
</v1.3>
</loadFolders>When using the format above, the last folder in the list takes precedence.
RimWorld version 1.0 does not support the load folder system, but it does support loading Defs, Patches, and Assemblies from /1.0. It will always look for Textures, Translations, and Sounds in the mod's root directory. If you create /1.0, RimWorld version 1.0 will not look for Defs, Patches, and Assemblies in the root directory.
RimWorld is not well-documented. When RimWorld is downloaded through Steam on Windows, the default directory of the RimWorld folder is C:\Program Files (x86)\Steam\steamapps\common\RimWorld. For XML documentation, RimWorld/Data and RimWorld/Source will contain a variety of examples from the base game. For C# documentation, the relevant code can be decompiled (such as with ILSpy) from RimWorld/RimWorld*_Data/Managed (especially Assembly-CSharp.dll and UnityEngine.CoreModule.dll). It is a good idea to find a mod which does something similar to what you're attempting to do and look at the code for that mod. There is a modding tutorial available on the RimWorld Wiki. A list of tutorials and resources is available on spdskatr's website. If you can't find something, ask for help on the Ludeon Forums.
The following table lists the recommended Harmony version for each version of RimWorld. The column titled "Include Harmony" includes a value of "Yes" for versions of RimWorld that should include 0Harmony.dll in their Assemblies folder, or "No" for versions of RimWorld that should depend on the Harmony mod instead.
| RimWorld | Harmony | .NET Framework | Include Harmony |
|---|---|---|---|
| 1.0 | 1.3.0.1 | 3.5 | Yes |
| 1.1 | 1.3.0.1* | 4.7.2 | Yes |
| 1.2 | 2.2.2 | 4.7.2 | No |
| 1.3 | 2.2.2 | 4.7.2 | No |
| 1.4 | 2.2.2 | 4.7.2 | No |
| 1.5 | 2.3.1.1 | 4.7.2 | No |
*There is conflicting information about which version of Harmony should be used with RimWorld version 1.1. According to Harmony's developer, you should use version 1.3.0.1, but it was standard practice at the time of its release to use version 2.x.