NavMesh bake producing strange unwalkable areas around trees

I made some trees using Mtree, saved it to a prefab, added to my terrain trees and painted them on the terrain in my project (and recreated in a fresh project). I then baked the NavMesh and I get this:


I am getting these random crosses under my trees. They are making my forests impossible to navigate. The issue only exists when I paint the trees using the terrain editor, if I drop a tree in manually it works fine but all my painted trees produce this. If anyone knows what's going on here or how to prevent it I would really appreciate your input.

 

Well. Looks like the raycast or whatever it uses to detect the obstacles is hitting your trees billboard foliage.
Im not really that much into the nuances of terrain, but does it somehow change the collider type in those objects when you paint them?

 

I'm hitting the same issue. did you end up resolving this?

 

Check out this thread: https://forum.unity.com/threads/does-the-component-navigation-work-with-terrain-trees-yet.488074/

 

I had the same problem and this was the only page I could find describing it. The solution I found was actually super simple. When creating a tree, there's a field that reads "NavMesh LOD Index." By default, it goes to last. My issue was that my last LOD layer was the cross-shaped billboard. After setting the Index to first, it fixed this annoying issue.

 

This worked for me, thanks! Just to clarify that post, you pick the LOD index when adding the tree in the terrain settings, not when creating the tree mesh itself.

 

Thanks for the fix. That worked for me. I set the NavMesh LOD Index to First instead of Last which had the billboards.