Navmesh isn't created

Troubleshooting ai
1

Hey Guys,
The Issue is basically simple:
I only have rare cases where the NavMesh Generation actually works.
Most of the time I just see that the returned NavMesh is null without decent logging.

This is what I see:

Jun 05, 2016 5:31:46 PM org.critterai.nmgen.ContourSetBuilder removeVerticalSegments
WARNUNG: Contour detail lost: Removed a vertical segment from contour. Region: 5
Jun 05, 2016 5:31:46 PM org.critterai.nmgen.ContourSetBuilder removeVerticalSegments
WARNUNG: Contour detail lost: Removed a vertical segment from contour. Region: 5
Jun 05, 2016 5:31:46 PM org.critterai.nmgen.ContourSetBuilder removeVerticalSegments
WARNUNG: Contour detail lost: Removed a vertical segment from contour. Region: 8
Jun 05, 2016 5:31:46 PM org.critterai.nmgen.ContourSetBuilder removeVerticalSegments
WARNUNG: Contour detail lost: Removed a vertical segment from contour. Region: 8

These are only Warnings but still I have no functional nav mesh. When I change the World it works, but it’s really hard .j3o dependent.
Does anyone have a clue on what to look for?
Changing the LogLevel did not help unfortunately…

2

My guess are invalid polygons and similar, that might look right rendered, but have gaps, not properly indices ect.

Does it work if you build a simple test world from cubes or something other simple?

3

Yep. I even have a “more complicated” Scene, but it’s mainly made out of boxes, with some small adjustments.
The Scene which doesn’t work should be simple aswell actually, I could try to remove the faulty stuff, though.

Shouldn’t unconnected polygons rather lead to a faulty navmesh instead of none?

Edit: That did work. I just removed the grass (which is wrong anyway since it’s not only a textured quad and shouldn’t be nav meshed anyway).

Still it would be good to know which mesh didn’t work, but since the Generator doesn’t seem to recognize a fault it can’t help me with that. (And the warnings were yet another geometry, btw)

4

I do not know how the algorithm works, but if it internally removes vertices in the hope of correcting the model, it might end up with non left.