I updated to 2020.1.2f1 a couple days ago and haven't noticed this issue. I'll keep an eye out. When is it disappearing (in Scene view while the game isn't running, or even while the game is running)? Do you have the latest runtime?

Thanks for reporting. We haven't encountered this problem with Unity 2020.1 so far, also after updating to the latest release did not show this problem. Could you please send us a minimal (if possible) reproduction Unity project that still shows this issue, as a zip package to contact@esotericsoftware.com. Then we can have a look at what's going wrong.

@IndieDoroid @[deleted]

I just had a similar issue, but it doesn't seem to be related specifically to Spine. Ever since updating to Unity 2020 (not sure if it happened on 2020.1.1f1 but its happening on 2020.1.2f1), I've been having issues where I have to "reimport" parts of my project. Just a minute ago my project randomly lost reference to one of my 3rd party Libraries (which are located inside my project, not in Packages or anything), and stopped showing a SkeletonAnimation in my Scene view. I only had 1 SkeletonAnimation in the scene, and was focusing on figuring out why the reference to my Networking Library was gone so I didn't test out too much with why the Spine animation disappeared.

I tried reloading the Scene, and I tried restarting Unity. Neither changed anything. I ended up right clicking on the folder that has my Networking Library assets, and clicking Reimport. Not only did that fix my reference to the Library, it made the SkeletonAnimation in my scene reappear.

The only thing that I can think of that might have linked those two issues: When I run my game, my networking library spawns the Player character by referencing my player-prefab in a Resources folder. All of my character prefabs are in the same Resources folder. When my project's reference to the Networking Library got screwed up and I tried to run the game, it tried to spawn the player and the error I got was essentially "Player prefab not found, try placing it in a Resources folder" (as though it didn't find the Player prefab, despite it definitely being in a Resources folder).

So, not sure exactly what is going on - but maybe you could just try right-click Reimport All on your project @IndieDoroid?

Update: Alright, I'm not sure if this is indeed related to Spine or not, but my artist just had the same issue. The artist was working on a scene, and restarted Unity and when he re-opened the scene, the Spine gameobjects were invisible. Doing a right-click Reimport on the prefab assets made them re-appear (maybe that does the same thing as the forced Update on the SkeletonAnimation?)

Info:
Unity 2020.1.2f1
Recent version of Spine runtime (from a couple days ago)
Artist is using a Mac

@IndieDoroid I doubt it has anything to do with it, but are you using Collab by any chance? Things are being screwy for us with Collab also.

Jamez0r wrote

Update: Alright, I'm not sure if this is indeed related to Spine or not, but my artist just had the same issue. The artist was working on a scene, and restarted Unity and when he re-opened the scene, the Spine gameobjects were invisible. Doing a right-click Reimport on the prefab assets made them re-appear (maybe that does the same thing as the forced Update on the SkeletonAnimation?)

Thanks for the info. When this happens again, could you please create a zip package of the project in the broken state (before reimporting anything) and send it to contact@esotericsoftware.com?

Another question: Do you have partial reload enabled in Project Settings - Editor - Enter Play Mode Settings?

Harald wrote

Jamez0r wrote

Update: Alright, I'm not sure if this is indeed related to Spine or not, but my artist just had the same issue. The artist was working on a scene, and restarted Unity and when he re-opened the scene, the Spine gameobjects were invisible. Doing a right-click Reimport on the prefab assets made them re-appear (maybe that does the same thing as the forced Update on the SkeletonAnimation?)

Thanks for the info. When this happens again, could you please create a zip package of the project in the broken state (before reimporting anything) and send it to contact@esotericsoftware.com?

Another question: Do you have partial reload enabled in Project Settings - Editor - Enter Play Mode Settings?

If it happens again I can zip the project in the broken state - is it okay that the project is a couple GB? I'd be uploading it to google drive. Also, if it happens on my artists computer, is it okay if its a zip of the project from a Mac?

I don't have anything enabled under the "Enter Play Mode Settings"

Jamez0r wrote

If it happens again I can zip the project in the broken state - is it okay that the project is a couple GB? I'd be uploading it to google drive. Also, if it happens on my artists computer, is it okay if its a zip of the project from a Mac?

Sure, no problem, since reducing the project could accidentally fix it. Zipping from a Mac is also fine.

Jamez0r wrote

I don't have anything enabled under the "Enter Play Mode Settings"

Thanks for the info, at least we can remove that point from the list.

Update: No need to send your reproduction packages any more, we succeeded in causing the issue to appear.

There is now an issue ticket here for you to subscribe:
[unity] Mesh not rendering on Unity 2020.1 · #1745

We did not say that it has been fixed yet, you can also see that by looking at the ticket which is still open and not closed. We will post here once it's fixed.

Yeah, I believe the root of some of these issues is that they changed the Asset Import Pipeline (or something like that) with Unity 2020.

I also had that problem with Animator state nodes being blank. There is a fix for it, I'll post it when Im at my computer in an hour or two

IndieDoroid wrote

I do notice 2020 is a bit screwy.. I also noticed today that some animation nodes in the animator controllers are blank when I click on them. :zipper:

The script below adds "Unhide Fix" to the Assets menu dropdown. Select the Animator in your Project window that needs to be fixed, and then do Assets->Unhide Fix.

I think I got the script/info from here: https://answers.unity.com/questions/1736606/animation-state-of-controller-not-showing-in-inspe.html

I might have modified the script a bit, I can't remember.

using UnityEditor;
using UnityEngine;

public class AnimatorBugUnhideTool : ScriptableObject {
    [MenuItem("Assets/Unhide Fix")]
    private static void unhide() {
        UnityEditor.Animations.AnimatorController ac = Selection.activeObject as UnityEditor.Animations.AnimatorController;

    foreach (UnityEditor.Animations.AnimatorControllerLayer layer in ac.layers) {

        foreach (UnityEditor.Animations.ChildAnimatorState curState in layer.stateMachine.states) {
            if (curState.state.hideFlags != 0) curState.state.hideFlags = (HideFlags)1;
            if (curState.state.motion != null) {
                if (curState.state.motion.hideFlags != 0) curState.state.motion.hideFlags = (HideFlags)1;
            }
        }

        foreach (UnityEditor.Animations.ChildAnimatorStateMachine curStateMachine in layer.stateMachine.stateMachines) {
            foreach (UnityEditor.Animations.ChildAnimatorState curState in curStateMachine.stateMachine.states) {
                if (curState.state.hideFlags != 0) curState.state.hideFlags = (HideFlags)1;
                if (curState.state.motion != null) {
                    if (curState.state.motion.hideFlags != 0) curState.state.motion.hideFlags = (HideFlags)1;
                }
            }
        }
    }
    EditorUtility.SetDirty(ac);
}
}