Install missing modules when opening project with pre-selected platform

[chrisyarbrough]

Use case: Avoid waiting for Library import, then switch platform in Editor GUI and wait again.

But there doesn't seem to be a CLI command for this in Unity, so might be tricky.

[HardCodeDev777]

Unity actually supports launching the Editor with a pre-selected platform via the -buildTarget CLI argument (e.g. win64, webgl, android, etc.).

In theory, this could potentially be implemented in UCLL by adding that argument when opening a project. However, I haven’t deep-dived into how UCLL launches the Editor / integrates with Unity Hub, so I’m not sure how it'll work in practice or whether there are edge cases (missing modules, Hub behavior, etc.).

[chrisyarbrough]

You're absolutely right, @HardCodeDev777!

I read the Unity docs and thought -buildTarget would only apply to building a player, because it's listed under Build arguments. But it turns out, we can simply pass that flag to our open command like so:

ucll open . -- -buildTarget android

This will open Unity in the current directory (dot), then separate the arguments and pass everything after that into Unity.

So, for the basic part (opening Unity on platform x), ucll doesn't need to provide any functionality.

However, now that you mentioned it: We might want to auto-install missing modules, since that's the idea behind ucll: a "fire and forget" command to doing Unity CLI things.

Currently, trying to open Unity with a build target for a module that isn't installed, shows this Unity dialog:

Users would then have to manually install the module. I think it would be a good idea to add the auto-install, since the open command already auto-installs the main editor version.

[HardCodeDev777]

I briefly explored Unity Hub configs and found that releases.json already contains detailed module metadata (download URLs, checksums, destination, etc.), e.g.:

    {
      "id": "android",
      "name": "Android Build Support",
      "description": "Android Playback Engine",
      "downloadUrl": "https://download.unity3d.com/download_unity/ffc62b691db5/TargetSupportInstaller/UnitySetup-Android-Support-for-Editor-2019.4.40f1.exe",
      "category": "Platforms",
      "installedSize": 1818207232,
      "downloadSize": 351883264,
      "visible": true,
      "selected": false,
      "destination": "{UNITY_PATH}",
      "checksum": "274eeea5bc0e0689a955b903bac56bd5"
    },

Platform modules (e.g. Android Build Support) are distributed as separate installers like UnitySetup-Android-Support-for-Editor-<version>, which Hub seems to just download and run against {UNITY_PATH}.

Maybe just replace platform name, version, type of executable and everything will work? Probably it's not that easy, but It can be a potential key for impleteting install-missing-modules command

[chrisyarbrough]

Instead of /Users/christopher.yarbrough/Library/Application Support/UnityHub/releases.json we can use e.g. /Applications/Unity/Hub/Editor/6000.0.64f1/modules.json from each editor installation. It contains all the modules supported by that editor, vs releases.json contains all existing modules. I already use the file here: VersionUsage
For the editor-modules command.

If we were lucky, Unity would use the same IDs to refer to a module/platform everywhere, but I fear, they don't.

So, when a user does:

ucll open . -- -buildTarget win64

We could check if that module has the selected property in the modules.json file (meaning installed).

But:

{
    "id": "windows-mono",
    "name": "Windows Build Support (Mono)",
    "slug": "6000.0.64f1-mac_os-arm64-windows-mono",
    "description": "Allows building your Unity projects for the Windows-Mono platform",
    "category": "Platforms",

The id is windows-mono and not win or win64 as the docs for -buildTarget require.

Some values, like android, ios, or webgl are the same. It wouldn't be pretty, but we could add a mapping, it would just mean that when Unity adds new platforms, our mapping might become outdated.

Is there maybe another way of using the same ids everywhere?

Experiment:

So, apparently, as the docs said, we can't use the module id from modules/releases.json when launching Unity.

But we can use the ids to install missing modules. (docs)

Another question: when to use mono and when to use il2cpp? On my system (mac), my modules.json only shows windows-mono, but for mac it only shows mac-il2cpp. windows and mac-mono are missing for me.

As usual, Unity's API is a mess. :D

[chrisyarbrough]

Did a quick analysis of the releases.json compared to the buildTargets from the docs:

BuildTarget (Unity API)	Module ID (releases.json)	Notes
android	android
cloudrendering		?
ios	ios
linux64	linux-mono or linux-il2cpp	Both exist on mac.
osxuniversal	mac-mono or mac-il2cpp	Running on mac: mac-il2cpp. Running on windows: mac-mono
tvos	appletv
visionos	visionos
windowsstoreapps		I think old and deprecated.
webgl	webgl
win	windows-mono or windows-il2cpp	Running on mac: windows-mono. Running on windows: windows-il2cpp
win64	windows-mono or windows-il2cpp

For IL2CPP vs mono it seems easiest/best to just try il2cpp first, and if not available, mono.
IL2CPP seems to be only available if the host platform is the same:

• mac can install linux-il2cpp and mac-il2cpp because both are unix
• windows can install windows-il2cpp, but only mac-mono

[chrisyarbrough]

Also, a simpler and more relevant use-case: After upgrading a project, the ucll command automatically installs the missing editor, but when Unity opens, it doesn't have the platform e.g. Android installed. That's unlucky, because switching platforms rebuilds the entire library (I think this is still true), in any case, it would be at least nice, to have the current editor platform available (the one preselected in the Unity project).