3D Animation play back is wrong when interpolation is cubic

[RichardR01]

Tested versions

Redot 4.3RC1, is present in Godot 4.3 stable

System information

Windows 10 - Redot 4.3 RC1

Issue description

I am creating an animation, with 6 meshes, 3 individually grouped into their own Node3D objects. I am animating those objects for ease, and also because one will be used for the left side and the other right side. I am using the Animation Player to animate these nodes.

My issue starts when I have keys, where the rotation is at Vector3(0, 0, 0), between 2.0 and 2.4. At frame 2.6 there is a key that sets the rotation of these nodes by 90 degrees on the Y axis. When I play or scrub through the animation, the 2 Node3D objects' rotation becomes skewed, when they should remain at 0. The interpolation for all the animation tracks are set to cubic for smoother transitions.

Steps to reproduce

Open the reproduction project, select the animation player, press play, and observe.

Minimal reproduction project (MRP)

reproduction.zip

[RichardR01]

I have tested this when interpolation is set to linear, and the problem goes away. So the issue is only present when the interpolation is cubic.

[Spartan322]

Could you check to see if this issue is reported in Godot's issue tracker? If not would you report it there. You didn't follow the standard to reporting the issue properly either when reporting system info and redot version info, when doing so you should validate this in Godot properly including system and version info using Godot, make sure your MRP works in Godot 4.3 stable and do not use Redot info when submitted there if you do.

[RichardR01]

This is the closest thing I found on the Godot github. https://github.com/godotengine/godot/issues/87637

As for not following the standard in reporting, what did I get wrong? I specified my OS, and Redot version. I also specified the Godot version I initially had the problem with, and the Redot version I am using.

[Spartan322]

The info you gave was not comprehensive as instructed by the template.

Tested versions

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