Navmesh won't build over a specific area?


Hello everyone. This square in my Navmesh appeared for seemingly no reason today and I can’t find how to get rid of it.

There’s obviously no volumes blocking it here.
Here’s what I checked/tried:

-Moving the landscape moves the square with it (so it’s probably tied to the landscape itself)

-Moving the NavmeshBoundsVolume doesn’t change anything

-Deleting then Adding back squares of the Landscape doesn’t make the bug dissapear.

-Deleting and creating a new NavmeshBoundsVolume doesn’t change anything.

-Sculpting in the square without navmesh doesn’t trigger any navigation rebuild.

-Making a copy of the Landscape, moving it and trying to build a new Navmesh also creates the same problem.

-Restarting UE4/PC as a last resort didn’t work either.

-Working with the NavmeshRecast parameters didn’t change the problem.

I’m now running out of options, I tried everything I could think of but nothing makes this ■■■■ square dissapear.

If anyone has an idea as to what’s going wrong with my Navmesh I’d be more than happy to hear it !

EDIT: After further testing it seems that the Navmesh around the square is going bonkers when I use any terrain tool near it. Here’s what happened when I used the Smooth tool near the outside of the square :


It pretty much removed the navmesh anywhere I used the smooth tool.

Not long after this post I finally found a workaround but not what’s causing the problem.

Here’s what I did :

-Save my map’s Heightmap on a png file

-Delete the old Landscape and Gizmo

-Create a new landscape with the heightmap and the same size parameters as the previous Landscape.

And this worked. In the end this is probably a bug, maybe the Landscape itself contained corrupted data ? I’m moving this post to the Bug Report section.

Here’s the result anyways:

Hey RomsIsMad,

After some investigation, I came across a similar issue that was marked as resolved in 4.16, but I’m not sure how related it is, as the description was fairly vague. Unfortunately, this issue cannot be made public due to it containing sensitive information.

I’d recommend upgrading a copy of the project to 4.16 Preview 1 just for testing purposes to see if it resolves the original issue if possible.

Otherwise, in order to investigate I’d need a way to reproduce the issue in a clean project on my end.
Could you give this a shot in a clean project, and provide a detailed list of repro steps or a test project that showcases the issue so I can determine if I need to get a ticket in for this?

Thanks

Hi guys,

having the same issue with the same symptoms
-4 components of the landscape didn’t have nav mesh on it

  • deleting them and adding, missing nav mesh starts to spread to adjusting components
  • using smoothing tools makes nav mesh desapire
    -ect

I found a workaround that worked for me. In the landscape menu, go to manage and to resize then just click apply with the same size. After that nav mesh got fixed for me, I didn’t lose foliage, height map, or vertex coloring on the terrain.
Unfurtantly, I don’t know how to reproduce to give you clear steps. My guess is that previewing height map on the components gets bugged for the nav mesh.
Am using Unreal 4.27.1 so it seems the bug is still there

Hope this help!

image