Joshpai
commented
2 months ago I came across this issue having experienced it myself, and was hoping for a workaround that wasn't just "make smaller maps". I did find a source on the unreal engine forums suggesting that increasing CellHeight would help, but this option isn't given to users at all and is hidden away inside the engine, locked to the default value of 0.5f.
UE Forum Post: https://forums.unrealengine.com/t/how-to-exceed-max-height-of-nav-mesh-generation/656748/5
Describe the bug
hi this is sort of a dumb bug and i don't expect it'll get fixed anytime soon, just sort of writing this here so people can figure out a fix if it happens to them
basically, if your map is super tall, nav can break
To Reproduce
i had a giant pit in my map that extended as far down as it could go (for the memes) whilst being inside the grid boundaries. for illustration this is what it looks like now
when i ran my gamemode i was finding that none of the npcs could navigate around anymore. when i looked further it turned out that the nav mesh wasn't generating properly. some symptoms were:
Expected behavior
tall maps work
Media/Files
some before and after pics for the gram
Additional context
also when the map was tall and the issue was occurring i was getting this warning during nav generation:
05:12:53 engine/Engine ClipPolysToHullClearanceInternal - too many non-reducing passes
i was getting this warning much more when my map was tall. i was also getting it when my map was not tall, but a lot less. e.g. tall map:
05:12:53 engine/Engine [39] TestBoxHullForClipDir - polyBack is empty
not tall map:
05:16:08 engine/Engine [3] TestBoxHullForClipDir - polyBack is empty
example log files attached
tall map log.txt not tall map log.txt