With mirror modelling, topology tear with moving a vertex away from the middle

[Cub0use]

What are you trying to do, and what do you expect to happen?

Using mirror modelling.

What happens instead?

Moving a single vertex away from the middle, then doing another transformation to one of the edges of the created triangle creates a tear in the model. Depending on where exactly the connected vertices are moved, the triangular face can have an inverted normal.

https://github.com/JannisX11/blockbench/assets/81629481/69aa6990-cfc6-42e0-bd01-2946a2aef527

Model format in which the issue occurs

Generic

Blockbench variant

Program

Blockbench version

4.9.0 Beta 2

Operating System

W10

Installed Blockbench plugins

N/A

[JannisX11]

Is this still an issue in 4.9?

[Cub0use]

Seems mostly fixed.

There can still be a tear and inverted faces, though the model remains symmetrical:

https://github.com/JannisX11/blockbench/assets/81629481/65714d7e-f8b2-4453-b7a9-c0d128e9671d

https://github.com/JannisX11/blockbench/assets/81629481/79768bd2-a3da-4ee3-a5e6-fb86b2194e3b

https://github.com/JannisX11/blockbench/assets/81629481/d5bd5801-cecf-48e0-afb4-3119d0a59e48

There were 13 faces for this element at the end of the video, one of the faces was collapsed like an edge.