Relationship between AvatarManager prefab and Player prefab

[jason-ortiz]

Hi all, I've been trying to figure this out by reading the code, but no luck for me yet. Using the "Start Here" project as an example, how is it that the AvatarManager spawns the Avatar where the Player prefab is and is aware of its existence, or vice versa? It's unclear to me how these reference each other.

[bnco-dev]

Hi @jason-ortiz! The Avatar transforms come from a 'hints' system. You provide a few hints about, for e.g., head and hands positions. Then the avatar makes use of them if it can. You can add or remove hints from the system at runtime. There's no direct connection between the Player prefab and the AvatarManager or the Avatars. The idea is that this way you can be free to use different Player prefabs, and it should be easier to attach an avatar to an existing player prefab from another toolkit, like MRTK.

For the Start Here scene, have a look at UbiqAvatarHintsHelper. It lives on the AvatarManager GameObject and attaches the simple Ubiq Player prefab to the AvatarManager at runtime. Try entering play mode while looking at AvatarManager - it adds a few HintProvider scripts at runtime to that object that do the actual attaching. Also maybe worth a look - the hint collection code is in AvatarHints, and the instance that gets passed to all created avatars is the hints member variable in AvatarManager.

[jason-ortiz]

Thanks for the reply. I realize I was looking at an earlier version of Ubiq locally before the introduction of UbiqAvatarHintsHelper, so I still wonder how it used to work before, but this answer is still great at explaining the current Hints system.

Looking briefly at the Unity project though, it seems like if introducing a new player prefab, it too will need to add Hint transforms then, and seems to depend on looking for objects with XRPlayerController. I am hoping to use Unity's XR Interaction Toolkit instead, so I may just use the UbiqAvatarHintsHelper as a template; I will probably also just update AvatarManager to allow for a GameObject reference to a Player to be passed in.

[bnco-dev]

No problem, hope it helps. In earlier versions hints were standalone Monobehaviours you could place directly on your new player prefab. We moved away from it because it involved editing standard player prefabs (those that come with SteamVR, MRTK, XRITK, etc), which we couldn't then distribute with Ubiq.

We're looking to redo our samples with Unity's XR Interaction Toolkit. It's not quite ready yet but you'd be welcome to the scripts for connecting the avatar to the hint system. I've attached them to this post. Just extract both files to your Assets folder, disable or remove UbiqAvatarHintsHelper on your AvatarManager GameObject and attach XRITKAvatarHintsHelper instead.

XRITKAvatarHintsHelper.zip