Exterior world cell navmeshing question.

[kingbeast88]

So I watched & read through a few tutorials on navmeshing and all of them were on interior cells.

I have been working on exterior world cell edits and came across something that I assume is a cell divider?

 

 

But I can't find any information on this. I want to know how to work around or with these, I have found that the nodes often overlap right on top of one another on these lines and red triangles always seem to touch edges though they don't seem to be connected like usual merely side by side.

 

I wanted to delete and maybe move some of the nodes on that green line, and manually created a new navmesh. However I don't know how to make the green line. I can make the nodes overlap, and set the red triangles edges to be touching however I don't know if the navmesh would be usable by npc's without that green line which I have no idea how to create. I know if I move the nodes on the green line the line moves with it which I'm sure is a bad idea. Any info appreciated.

[EPDGaffney]

Have you tried using Finalise? I don't remember having to do anything with that line myself. If the edges are touching, NPCs should not have a problem traversing it (just did this with three exterior cells last weeks and that seemed to be the way it worked). But test it to be sure. I don't believe cells are actually determined by the navmesh in any way, so just make sure everything touches and test it in-game. Use GECK Power-Up, or GECK with NVSE, and it should give you warnings. If it gives you a warning about this, you can google it and/or post it here.

[kingbeast88]

I do have GECK Power up and with NVSE, I'll use Finalize save my edits and reload back in GECK and test to see how it goes.

 

Edit: Cleaned up all navmesh errors and used finalize however the thick green line didn't reappear upon reloading in the GECK, no errors though.

 

Edit 2: Npc's will not cross over the navmesh where the green line was but now no longer is they immediately repath.

Edited January 12, 2018 by kingbeast88

[Deleted1205226User]

This might have the info you need:

https://www.youtube.com/watch?v=q2pZmWgJ0FE

[EPDGaffney]

Weird, because I didn't have any problems like that. If you can't revert to before this happened, you can use FNVEdit to delete the edit to the navmesh. What I'm getting from the video is basically not to break the green line.

Never mind, this appears to be unnecessary.

 

 

My only other piece of advice that I can offer is that if you prefer not to revert, just check your Z axis; it's possible the verts look as if they're touching but one my be much higher in the air, or at least enough that your NPCs aren't interpreting them as connected. I honestly don't believe that NPCs care about the green line. I could of course be wrong, but my NPC is chasing me all over the place as long as the verts are actually touching.

Edited January 12, 2018 by EPDGaffney

[madmongo]

Outdoor navmeshes work mostly the same as indoor, except that they can't cross cell boundaries.

 

When you finalize your outdoor navmesh, it will attempt to link up with the neighboring cell's navmesh. Any line segment along the edge of the navmesh that successfully links to the next cell will turn green. Navmesh triangles will often end up being automatically split by the GECK so that it can match up vertices. If part of the cell border isn't green, then the navmeshes between the two cells in that location aren't linked and NPCs won't cross from one cell to the other properly.

 

You don't have to be exact when lining up vertices on your navmesh, but you have to be reasonably close. If your navmesh triangle edges are too far away from the triangle edges in the next cell, the GECK won't be able to match them up. You don't have to match vertex for vertex, but if you don't match vertex for vertex, what can often happen is that part of the triangle is too far away vertically from the triangle in the next cell and the GECK refuses to link it. So matching vertex for vertex will generally give you the best results.

 

If the line isn't turning green, delete the navmesh triangles along the cell border and redo them so that the vertices are closer, then finalize your navmesh for that cell again. Remember, any cell that you change the navmesh in needs to be finalized. Just making navmesh triangles isn't enough.

 

I haven't watched the video so I don't know what you are referring to when they say don't break the green line. You can change landcsape and navmeshes around all you like, just make sure you edit the navmeshes of any cell involved, make sure you get your new navmeshes to line up well enough that all of the lines turn green, and make sure you finalize any cell that you modify.

[kingbeast88]

Thanks for the video pixelhate & the info madmongo. Gonna give this another ago when I get the chance.

[EPDGaffney]

The video seemed to move verts that were on the green line but not delete any, in order to make the navmeshes of two cells circumscribe a house he'd added that was half in one cell and half in the other. So I thought that may be the best way to approach it. But what you're saying is basically what my experience indicated, which is that as long as the verts are touching, finalising the navmesh will preserve the green line. That and check the Z axis.

[madmongo]

In my experience, moving vertices is not the best way to go about something like that. If you're not careful you can accidentally end up with triangles that have flipped normals and a navmesh for that cell that doesn't work. You are better off deleting any triangles that go under your house (in both cells) and then add new triangles to circumscribe the house.

[Mktavish]

In my experience, moving vertices is not the best way to go about something like that. If you're not careful you can accidentally end up with triangles that have flipped normals and a navmesh for that cell that doesn't work. You are better off deleting any triangles that go under your house (in both cells) and then add new triangles to circumscribe the house.

 

+1 Ya that is my experience ... don't be afraid to start selecting triangles and punching up delete. And I would add ... it is always a good idea to hit the balance button to see where it wants to shift stuff ... then in the final ... if you really need stuff a certain way ... don't hit balance.

Edited January 12, 2018 by Mktavish