T-Junctions in CalculateTriangles

Hi,

we're using NavMesh to build the navmesh, and then extract it using the CalculateTriangles function. This has worked well so far, but now in one created navmesh, there seems to be a T-junction, see attached screenshots.

As you can also see from that, moving the colliders out a bit (second screenshot) removes all T-junctions. It appears to have something to do with the colliders touching the x = 0 axis.





Is this working as intended from the NavMesh side (ie. does CalculateTriangulation() allow for T-junctions to exist)?

 

Note on the visualization: we're rendering the triangles slightly inset, with magenta edges indicating exterior edges, and grey edges indicating interior edges with a neighbor. Red lines are the edge normals.

 

Another note: we're using Unity 2020.2.1f1