Really big navmeshes

Snebjorn

I'm working on a really big outdoor scene (about 3 square kilometres) which I've built as a number of meshes that fit together. My plan is to create navmeshes from these (basically just removing all the unwalkable areas) and then switch between them depending on the location of the player.

My question is: is there a practical upper limit to the size and polygon count for navmeshes that I should take into account for this?

ChrisIceBox

Of course, it depends on the hardware you play on, but the Mesh Collider algorithm's calculations are tied directly to the number of vertices in your NavMesh - size isn't a factor.

Snebjorn

Ran some tests and even with the number of vertices maxed out (65535) the impact was neglible(-ish). In terms of performance, it seems that my time is much better spent on setting up LODs and optimising the scene layout for occlusion culling.

Snebjorn

Here's a short clip of a quick test I ran while testing Unity terrain settings. Please ignore untextured bits et cetera - but I think it runs ok with a combined navmesh of around 500K vertices and point'n'click movement.

The full terrain is as mentioned around 3 square kilometres - and it takes FOREVER to walk through the whole thing!

https://youtu.be/4mBH4O9AgDc

Big_Cow

Very cool!