Tips and tricks link for Navmeshing

[TennesseeTuxedo]

I got the basics down and know where to look for more detail on the more advanced functions of navmesh. But the help I've found mainly goes over how to do things, not necessarily how to do them well. I navmeshed my first little mod and it appears to work but there are some little quirks still like NPCs walking into the work bench for a while before using it, or NPCs jitterring back and forth. I'm looking for an online help resource in the format of a list of:

 

In game problem behavior --> what to check in Navmesh

Edited July 17, 2015 by TennesseeTuxedo

[DaemonGrin]

Build navmesh around items not under give reasonable area from walls and objects you don't want them getting stuck on (there is a little "falloff" for npc's to use navmeshing beyond the actual triangle so if you build right along the edge of something like the workbench they will try to walk through it. Use the find triangle in the navmesh toolbar to find bad spots and finalize. Not much more to it unless you are navmeshing water toggle water off in view > show/hide makes it easier and use the toggle water on in navmesh toolbar if the water area is swimming depth. Those are the tricks I know other then stairs you don't have to do each step (the first time I played with navmeshing I did every stair) after examining vanilla navmeshing I noticed they just went from the bottom to the top with 2 triangles ><.

[TennesseeTuxedo]

Thanks I was wondering about the "falloff" space. I guess you have to be careful with work benches because the legs are setback from bench top a little.

 

What isn't clear is how aligned the triangles have to be. I'm very careful with them of course but sometimes a seam of two triangles appears just a tiny bit off, the seam line is just a hair thicker than others but can't get them perfectly aligned (or maybe there is a "snap to" alignment key?). What is the misalign tolerance and what happens to the NPCs when there is some misalignment? Is overlap bad? Do these make NPCs zig-zag?

 

Is finalize required for small navmeshes? (portable tent kind of thing, probably 50 triangles)

[DaemonGrin]

Are you not connecting the triangles? CTRL + Left click 2 triangle verts and then CTRL Right Click where you want the 3rd nav vert to be. Usually it autofills sometimes you gotta press A to fill. By using existing verts you can build a single navmesh. It sounds like you are making several and overlapping them this is bad you can get some really weird pathing issues from that. You can also ctrl left click 2 verts and merge them with Q (or use the navmesh toolbar.)

 

Finalize use very useful it can make small corrections and in your case might join some of the vert if they are close enough to each other etc.

[TennesseeTuxedo]

Definitely connecting them properly as you describe. I am talking about cases where you might navmesh around a chair or something and for example have a smaller triangle near the chair that needs to butt up against a larger "room triangle". The two triangles share one vertex only and their edges have to align. The smaller triangle's edge length is less than the length of the larger triangle's edge so they can't share two vertices, so I am assuming the only thing you can do is manually line up seams. Curious what the seam overlap/gap tolerance is.

[DaemonGrin]

When you map smaller sections you gotta get creative in the size of triangles. instead of 1 large make 3-4 smaller with the center (depending on how you do it) having 2 verts that you can build from for the chair /V\ <--like that. In my experience there isn't a tolerance they will teleport to a separated navmesh when they walk long enough against the edge of the pathing if they are dead set on going that one way.