NavMesh fail to rebuild at runtime dynamic obstacles

Hi !

i came to hit a strange bug with dynamic obstacles, when an obstacle moved, the nav mesh has to rebuild the area, so it discard it, but never rebuild it…

at runtime :

By luck, i found that if i make the area to be rebuild in editor and try again, it does work (only for this area, other still buggy) , and after rebuilding the full mesh, everything works again.

The nav mesh rebuild is buggy on one of my coworker computer, so we disabled the auto one, and only i rebuild it from time to time, so the mesh was few weeks old ( but it was already a 4.17.2 one ). so the lvl had changed a bit, but not that specific part of the lvl

So i’m not asking for a fix as the workaournd is good enough and 90%+ of people probably have auto nav mesh generation. But just posting this so you guys know it exist, and if somebody has the same problem he doesn’t loose half a day thinking he broke something :stuck_out_tongue:

have a good day ! :slight_smile:
Additional infos:

-c++ project, 4.17.2, from luncher binaries

-my “runtime Generation” Setting is “Dynamic modifiers only”

-it does work on an other smaller test map in the same game with similar settings

-it does work if i set Runtime Generation to “Dynamic” but i don’t want a full rebuild of areas


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