ERROR: get_child_count: Caller thread can't call this function in this node.

[Hanshattori]

Godot version

Godot v4.1.beta1

System information

Ubuntu 20.04.5 LTS (Focal Fossa) - Vulkan (Forward+)

Issue description

Hello,

I just tried to migrate my project from 4.0.3 stable to 4.1 beta and I have a very similar looking problem to the issue #77780, but the solution does not work for me and there is also the thread error.

Solution in the linked issue was to add the reference to the skeleton, but this was there all the time in my case. This is for a project going back to 4.0 alphas and upon upgrading all characters are locked in place with just the animation playing. Characters and bonemap are from Mixamo. I am not using threads anywhere in the project. I am not calling get_child_count anywhere in the project.

Steps to reproduce

"N/A"

Minimal reproduction project

"N/A"

Complex project, unable to reproduce the issue with minimal reproduction project.

[AThousandShips]

You need to set up thread safety for your nodes in 4.1, see here, you'll need to eliminate that the threading is the cause before we can really investigate I'd say

[Hanshattori]

Everything is set at default (inherit) so as per documentation it should then be in a main thread with group order 0.

Few more information :

• All other scenes seem to be fine, SplashScreen, Startscreen, Loading Screen, Options, GUI, simulation control, other actors, just the characters are locked in place.
• All functions of the locked characters seem to be fine, process delta running and AnimationPlayer OK and running animations.
• Remote scene tree seems fine.
• Not messing with threads.
• I tried disabling the Thread Model Avoidance in Navigation Project Setting and nothing changed. The same with other thread project and editor settings.
• Project was updated with every 4.0 beta and I just skipped the 4.1 Dev versions - this error only happens in 4.1.beta

[AThousandShips]

Then it sounds like a threading bug probably in the editor, the skeleton plugin possibly

[Hanshattori]

So I did one more test, I removed all the locked characters scenes from the world tree and expected the errors to go away, but I got:

• the skeleton RID errors are gone as expected.
• ERROR: get_child_count: Caller thread can't call this function in this node: error persists and prints to the console every 2 seconds.

[AThousandShips]

Yes this is probably due to a threading bug in the editor, unsure what or why, but it is related to recent threading changes in 4.1

[Hanshattori]

I tested with 4.1 Stable and the issue seems to be solved.

There is a new problem with baking NavigationMesh3D at a runtime which is extremely slow to the point of stopping the simulation for a second, but I do not think it is related to this issue and I will open a new issue if unable to resolve with further research.