DocFX for Unity

DocFX usage example for Unity projects

DocFX tool generates a clean documentation that looks like the Unity documentation with a manual (written in Markdown) and a scripting API (from the C# scripts of the project).

This repository contains a simple Unity example project which documentation is automatically generated and deployed online: https://normanderwan.github.io/DocFxForUnity/. It references both C# API and Unity API.

DocFxForUnity documentation manual

DocFxForUnity documentation scripting API

Setup your documentation

1. Install DocFX.

2. Copy the Documentation/ folder and DocFxForUnity.csproj to your Unity project:

     .
     ├── Assets
   + ├── DocFxForUnity.csproj
   + ├── Documentation
     ├── Package
     ├── ProjectSettings
     └── README.md

   You can rename DocFxForUnity.csproj to match your project — just update the filename in Documentation/docfx.json under metadata[0].src[0].files accordingly.

3. Edit the following properties in Documentation/docfx.json, keep the others as it is:

     {
       "build": {
         "globalMetadata": // Edit your documentation website info, see: https://dotnet.github.io/docfx/tutorial/docfx.exe_user_manual.html#322-reserved-metadata
         {
           "_appTitle": "Example Unity documentation",
           "_appFooter": "Example Unity documentation",
           "_enableSearch": true
         },
         "sitemap":
         {
           "baseUrl": "https://normanderwan.github.io/DocFxForUnity" // The URL of your documentation website
         }
     }

   It's the configuration file of your documentation. See https://dotnet.github.io/docfx/tutorial/docfx.exe_user_manual.html#3-docfxjson-format for more details.

4. Edit Documentation/filterConfig.yml:

   apiRules:
   - include: # The namespaces to generate
       uidRegex: ^Your\.Namespace1
       type: Namespace
   - include:
       uidRegex: ^Your\.Namespace2
       type: Namespace
   - exclude:
       uidRegex: .* # Every other namespaces are ignored
       type: Namespace

   It tells DocFX which namespaces you want to generate the documentation. See https://dotnet.github.io/docfx/tutorial/howto_filter_out_unwanted_apis_attributes.html for more details.

5. Document your classes and methods. See https://docs.microsoft.com/en-us/dotnet/csharp/codedoc for more details.

6. (Optional) Add your manual pages:

   • Write a Markdown file for each page in Documentation/manual/.
   • Keep a list of these pages on Documentation/manual/toc.yml.

7. (Optional) Add resources such as images:

   • Copy them to Documentation/resources/.
   • Reference them on your docs or manual pages.
   • See https://dotnet.github.io/docfx/tutorial/links_and_cross_references.html#link-to-a-file-using-relative-path for more details.

8. (Optional) Document your namespaces:

   • For each namespace, add a Assets/Scripts/Your/Namespace1/Your.Namespace1.md file:

     ---
     uid: Your.Namespace1
     summary: Description of the Your.Namespace1 namespace.
     ---

   • See https://dotnet.github.io/docfx/tutorial/intro_overwrite_files.html to know how it works.

9. Generate your documentation:

   • On a command line opened on your project, run:

     cp README.md Documentation/index.md
     docfx Documentation/docfx.json --serve

   • The generated website will be visible at http://localhost:8080.

If you want to have a more similar look to the Unity documentation, see this UnityFX template for DocFX: https://github.com/code-beans/UnityFX.

Generate automatically your documentation

If you're using GitHub:

1. Copy the .github/workflows/documentation.yml workflow to your Unity project:

     .
   + ├── .github
   + |   └── workflows
   + |       └── documentation.yml
     ├── Assets
     ├── Documentation
     ├── Package
     ├── ProjectSettings
     └── README.md

2. Configure the Pages of your repository to use GitHub Actions.

3. Commit and push on the main branch: your documentation will be built and deployed to https://<username>.github.io/<repository>.

If you're using GitLab, use the provided .gitlab-ci.yml. Generated website is pushed to a public/ directory. See the GitLab Pages documentation for more details.

Troubleshooting / FAQ

• DocFX outputs: Warning:[ExtractMetadata]No project detected for extracting metadata.

  Solution: Make sure you copied DocFxForUnity.csproj (or your renamed version) to the root of your Unity project, and that the filename matches the entry in Documentation/docfx.json under metadata[0].src[0].files.

• DocFX outputs: Warning:[ExtractMetadata]No metadata is generated for Assembly-CSharp,Assembly-CSharp-Editor.

  Solution: Make sure you included your namespace in Documentation/filterConfig.yml:

  - include:
    uidRegex: ^Your\.Namespace1
    type: Namespace

• MSBuild outputs: Unity managed DLLs not found.

  This means DocFX could not locate Unity's managed DLLs. It looks in three places, in order:

  1. The UNITY_MANAGED_PATH environment variable (see below).
  2. lib/UnityEngine/ at the project root (populated automatically by the CI workflow).
  3. The default Unity Hub installation directory for your OS.

  If Unity Hub is installed at a non-default location, or you want to target a specific Unity version, set UNITY_MANAGED_PATH (see Advanced: UNITY_MANAGED_PATH below).

• If you want to reference a specific version of Unity, change this line on your docfx.json:

  "xref": [ "https://normanderwan.github.io/UnityXrefMaps/<version>/xrefmap.yml" ],

  where <version> is a Unity version in the form of YYYY.x (e.g. 2022.3, 2023.2, 6000.0).

Advanced: UNITY_MANAGED_PATH

By default, DocFxForUnity.csproj auto-detects the Unity managed DLLs from the standard Unity Hub installation directory. Set UNITY_MANAGED_PATH when you need to:

• Use a Unity version installed at a non-default location.
• Pin to a specific version when multiple Unity versions are installed.
• Work without Unity Hub (standalone Unity install).

Point it to the UnityEngine subfolder inside your Unity installation's Managed directory:

OS	Example path
Windows	C:\Program Files\Unity\Hub\Editor\6000.0.73f1\Editor\Data\Managed\UnityEngine
macOS	/Applications/Unity/Hub/Editor/6000.0.73f1/Unity.app/Contents/Managed/UnityEngine
Linux	~/Unity/Hub/Editor/6000.0.73f1/Editor/Data/Managed/UnityEngine

Set it in your shell before running DocFX:

# macOS / Linux
export UNITY_MANAGED_PATH="/Applications/Unity/Hub/Editor/6000.0.73f1/Unity.app/Contents/Managed/UnityEngine"
docfx Documentation/docfx.json --serve

# Windows (PowerShell)
$env:UNITY_MANAGED_PATH = "C:\Program Files\Unity\Hub\Editor\6000.0.73f1\Editor\Data\Managed\UnityEngine"
docfx Documentation/docfx.json --serve

Disclaimer

This repository is not sponsored by or affiliated with Unity Technologies or its affiliates. “Unity” is a trademark or registered trademark of Unity Technologies or its affiliates in the U.S. and elsewhere.