Hi guys! I was watching the tutorial for Navmeshing, everything is fine... up until he starts to mesh a cluttered room -- I noticed he has edge selection on.. instead of what he was showing us before where he only had vertices on while doing a small empty hall.

So should I always have edge on - or only turn edge on for doors, stairs, and clutter/cluttered rooms?

I always have all three turned on at the same time, it doesn't hurt anything.

Some pointers for Navmeshing:

1. Use the "W" key to quickly switch between NavMesh viewing modes, this is very important as you will see.

2. Use the "B" key outside to show the cell boundaries, which is critical for Navmeshing the cell boundaries correctly in exterior cells.

3. Try to make as large of triangles as you can, but in general (as Echonite points out), don't try to get elaborate as the GECK is going to re-write it when your done. Your key goal with NavMeshing should be to cover the areas where NPCs can go.

4. Do not make too-extreme of angles with the triangles, or the GECK will whine about it.

5. You cannot have more than 2,000 Navmeshes in any cell. More than this, and the GECK will error-out. Furthermore, Joystick Monkey says any more than 2,000 is bad for frame rate.

6. The cell boarders in exterior cells are Tricky. What you have to do is Navmesh each side of the boarder and line-up the edges as closely as possible. Each exterior cell has its Own mesh, and they don't physically connect to boardering cells. If you get the meshes at the boarders close-enough, a fat green line will appear at the boarder when you Finalize (see below step 9).

7. The "Tab" key is Huge. You will see this in the tutorial, it allows you to switch which two vertices from the last triangle that you have selected, so you can quickly "walk" your mesh across.

8. The "Test Cell Navmesh" is fabulous, you click it, then click a To and From spot on your mesh (click triangles), and the GECK will draw a fat line across the mesh where it Would send the NPC if it was trying to get from A to B. Its very effective in letting you know where the game would send your NPCs in specific game settings.

9. This takes time to do right, and I strongly recommend the tutorials from Bethesda. I started with them, and thanks to the short-cuts and methods they use I have since Meshed about 12,000-15,000 triangles. Their techniques and short-cuts REALLY make a big difference.

10. When your done with your mesh, do the following:

a. Save.
b. Click the, "Balance for Optimization" button. This will re-write the mesh in a more efficient form and you'll notice the number of triangles drops.
c. Check the mesh, as sometimes Balance can remove triangles if the space is too-narrow for NPCs or too angled. Fix any missing spots as necessary.
d. Click the, "Find Cover Edges" button, which finds the good corners that NPC's can use for cover while in combat.
e. Click the, "Finalize Cell Navmeshes" button, which will finish things up. If you have any errors, they will show up here.
f. Save Again.

Then to Test the Navmesh:

1. Open the Navmesh feature.

2. Select the Path Test button, which looks like a little path with 3 dots (in the middle).

3. Double Right-click two spots in your cell (give a second between the two spots), and you should see a big Green line showing you where the game will path the NPC. If it's not green, then the path was too-long to be efficient for the game engine.

4. Be very careful with this, as you can very easily crash the GECK if you hit Esc or try to do something else while Path Testing. When your done with a path-test, click the Path-testing button to turn off the feature safely.

Luck!

Miax

As for having Edges on, that simply means you can add a point in the middle of an edge. I have everything off but vertices, but if i need to select an edge or triangle, I turn on the respective function, use it, then turn it back off. This is so I dont try to make a point somewhere, or select two points to add a third (and make a triangle) and accidently select an edge or triangle instead of a vertice.

If you are working on a multi-level navmesh, its very difficult to place a new navmesh 'above' another navmesh.
But, I found that if you "only" have the 'Select Vertices' on you can easily place more navmesh above the others.

Awesome! Fantastic Information

Going to copy and save this in wordpad

Thanks alot

Although it would seem I can't use "Test Navmesh" without it crashing everything D:

ok got it to work... but still, like you said - it's a touchy subject xD

and I always crash when closing GECK after Navmeshing :/... no big deal though, as long as it doesn't happen when I click save

Yes testing of the Navmesh is a "delicate" feature in which you can crash the GECK easily if your not careful. To try and prevent the crashes, always hit the escape key a few times when your done working to cancel any operations or selections that you might not be able to see. Then make sure you un-click the Navmesh button and wait for the Navmesh bar to clear out.

Crashing when closing the GECK is something I have had to live with forever - I've not found a way to prevent it.

I fiound it helpful to use the "Balance for Optimization" button often when navemeshing.

And be prepared to redo many parts to your navmesh. Especially 'thin' areas or on steep stairs.

Oh yea. So many times I say 'Balance for Opt' and it helps alot of my navmesh, but completely screws up chunks of it.

If I stay away from using long thin triangles as the tutorial states, it works good for me anyway.

Yeah thats what I do to. The engine very specifically will remove triangles that create pathways which are too-small for NPC's to pass through. The chances are that if the Optimizer removes some mesh triangles that make a path through a thin hallway or thin space, it's because many NPCs will get stuck on the geometry and won't be able to follow the player smoothly (especially big monsters like Deathclaws and Sentry bots). In these cases I find it's a better idea to re-work the area so that the pathway is wider, and thus passes the optimizers size restrictions.

What I do find annoying is that the optimizer will remove some staircase meshes as WillieSea points out, and while I also think this is because the optimizer doesn't think that all NPCs can path upwards at the angle we're specifying in our meshes. I find that NPCs can indeed path up some stairs that the optimizer wants to remove, but also find that if I re-mesh it carefully, I can get the optimizer to pass it. In general I think the optimizer does more good than harm.

Miax

I think you summed it up well buddy