4.5.1: Navmesh doesn't work with foliage rocks

I made a simple terrain level, put a large navmesh bounds on it, and then painted some trees and rocks using foliage (set to Block All in collision settings.)

Unfortunately, the navmesh doesn’t build proper polygons around these rocks – it’s as if it sees the rocks in different places than they are.

I have tried re-building geometry, saving the level and quitting and re-starting, and a few other things to try to see if I could provoke it into working, but nothing makes it good.

Look especially at the crescent in the lower-center of this screen shot – that’s my player start location. The player can’t walk very far…

I don’t know if this also affects earlier engines, but it does affect 4.5.1.

Edit: As asked, here are the painting and instance settings (and the Landscape settings):

Hi jwatte,

What are the painting and instance settings you are using for your foliage, can you post a screenshot here for me of each? Thank you!

In addition to adding the painting/instance settings, I think the “ghost” rocks may have been real at one point, and then deleted by un-painting them (shift-paint.)

Hi jwatte,

After removing the rocks, did you rebuild paths?

Hi jwatte,

We have not heard from you in quite some time. I am marking this as answered for tracking purposes. If you are still experiencing this error, please respond with the requested information.