Is there a maximum nav mesh bounds volume size (particularly large Z) after which dynamic navmesh generation start to break?

I’m not sure if I have some incorrect settings with my navigation or if I’m hitting upon some limitation of the engine/recast.

I am attempting to use dynamic navmesh generation and using navigation invokers, my terrain is very large about 300,000 unreal units by 300,000 by 50,000 units tall. 300k x 300k x 50k.

When I make my navmesh bounds volume smaller than that, the default navmesh generates perfectly.

But when I size up the navigation bounds volume to 300k x 300k x 50k the navigation invokers aren’t triggering anything and the navmesh never generates. If I change my cell size and cell height to 700 though then I do get a navmesh generating even with the very large nav mesh bounds volume, but the resulting navmesh is very inaccurate to my terrain. See the images below for that inaccurate navmesh (those peaks shouldn’t be there as the terrain is flat).

Is there some setting I need to change to get more accurate navmesh with a large world and large navigable area?

Example:

I’m Having exactly the same problem, im doing a level streaming with nav mesh invokers, using spawn triggers to spawn my AI Actors.

If i set my nav mesh to 10k x 10k x 10k (x || y || z) Nothing generates, if i make my nav mesh 10k x 10k x 800 it generates perfectly, so i thought maybe all i need is to take away my Y and add to my Z (since im doing a side scroller) but it wont work, basically any nav mesh higher than 800 wont generate.

Anyone knows about this or can help with it?

I just ran into this problem myself and found your discussion.

Our producer of all people fixed it by messing around with the RecastNavMesh settings and discovered that the solution was to increase the Cell Height value. In our scene he raised it from 1 to 10 and the problem was solved.

We don’t use navigation invokers though, so YMMV, but try it out and see if it works :slight_smile:

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Very old i know, but still the best answer I’ve found for this. I linked Jonas’ solution in another thread as well. Thanks!

How long does it take you to generate a navmesh for such a big terrain?