Saving imported mesh to .tres changes geometry

[aristides86]

Tested versions

v4.2.2.stable.official [15073af]

System information

Win10

Issue description

When importing obj made in Blender, making it unique and saving as .tres geometry becomes slightly warped. Location of vertices changes and meshes no longer align together.

Steps to reproduce

Terrain_01_GEO.zip
Import obj into Godot

Place the mesh into a new scene. From inspector make the mesh unique. Save it as .tres
In the project I collect meshes into a mesh library for a gridmap. Original objs align perfectly, but new treses produce gaps between tiles.

Minimal reproduction project (MRP)

no need

[AThousandShips]

Does this occur with "optimize mesh" turned off?

[aristides86]

Looks like that's the problem. It doesn't seem to warp the mesh with Optimize disabled.

[Calinou]

Looks like that's the problem. It doesn't seem to warp the mesh with Optimize disabled.

I don't see why that would happen, considering that import option does literally nothing: #94100

Are you sure this is not simply because reimporting the OBJ fixes the issue?

[aristides86]

You probably right. I'm trying to recreate it again and it's not happening anymore.