Navmesh generated perfectly yesterday.
Today it doesn’t.
I wish I had more information, but I simply don’t.
Any help is appreciated. Thank you.
navmesh_issue.blend (670.9 KB)
To clarify, I’m trying to use this as a Navmesh, and generate navmesh data. I am not trying to generate a separate mesh from this to use as a navmesh.
It prints this error:
Error: building NavMeshObject, can't find vertex in polygon
I also had problems with a much simpler Navmesh. Once I got this error I didn’t find any way to correct it.
It’s almost like the mesh it’self is corrupted, isn’t it?
Anyone else have any ideas?
i encountered lot of problems with the navmesh before considering it was junk no one could possibly rely on for a game that hasn’t characters stucked in some corners. So unless you want to make a game on a simple Plane map, like everyone else, you gonna have to go through the programming of your own system
many subjects of this kind on the forum. Otherwise, yes, maybe the navmesh has improved since.
How is the recast technology any different than Unreal’s or any other leading engine?
“recast technology” ? https://docs.unrealengine.com/5.0/en-US/API/Runtime/Navmesh/Recast/
i guess big game engines embeds lot of technologies in their “navmesh” but for upbge/bge it seems more primitive.
I can just say that the navmesh in upbge hasn’t been improved since many years. And that aspect is too often disregarded by people making games on upbge … As you can see on youtube, most people ‘making’ games in upbge is about parenting a gun to a camera and they are happy with that… never a single npc around.
Just saying you don’t wanna rely and build your game on something that bugs already in the early stage of development.
If you really want to stick to navmesh, did you try to create a clean square grid inside blender and use it as the navmesh rather than trying to generate a buggy one ?
Any new geometry I add can properly generate data for use as a navmesh.
The one included in the above blend was hand made, and worked well one day and then didn’t another.
I easily can do a clean start, and it will work, but I want to save my progress.
I’ve exported the mesh as an obj and re-imported. No luck.
If you add geometry to the included mesh, that new geometry generates navmesh data while the rest of the mesh does not, save one or two spots.
So yeah, I easily could do it over from scratch, but I don’t want to do that.
you gonna have to find a way to have it working in 99,99% of cases . Better generate once for all your final navmesh rather than extending it with new geometry …
Maybe make a very primitive version of your final map (basically the plane on which your characters will walk on) , duplicate it , on this duplicate removes all inside vertex (edit - mesh->cleanup->limited dissolve) and then subdivide the plane with some clean aligned vertex again (edit-subdivide) then use it as your navmesh
The question though is why.
I want to understand why my above Navmesh can’t generate data, and to fix it.
not sure upbge’s navmesh system will handle this nicely … you gonna pull your hairs off with silly npc getting stuck at stairs or in corners.
Better use a pragmatic approach : make npc’s use map-node-based system using empties . Each node/empties represents a location the npc will be able to reach in a restricted area . Check again the 2 posts i linked above. You gonna have to learn some python scripting for that.
On the other hand i would be interested to see if you can get any satisfying result out of the navmesh … since i gave up with it after many tries
Thanks for the advice. I do appreciate it.
However, I already have a robust, combination of map-nodes, and the navmesh, and some sneaky tricks.
Yesterday, NPCs organically walked up stairs, didn’t hug the walls, naturaly avoided other moveing NPCs, ect. It worked very, very well.
Which is why the topic of this is fixing the navmesh, not “how to do pathfinding”. 
yeah i’m sorry, i myself know how annoying when people don’t stick to the question and bring their views. It’s just that i tested navmesh like 3,4 years ago. What upbge version are you using ?
2.79.
Archaic, yes, but I began migrating to Unreal years ago. This is just an old project that doesn’t run in UPBGE or 2.8+ that I like to return to from time to time. It works too well to bother re-making it from the ground up in Unreal again.
BGE 2.79 , UPBGE 0.25 or Range 1.0 ?
Sorry, blender 2.79. I never bothered with UPBGE. I reasoned if I was to learn a entire new system, I’d learn Unreal, hence, Unreal.
Range Engine works exactly like BGE 2.79 (since based on 2.79). But performances are really better.
i think you just need to change your .blend into .range … and that’s it
Good to know. This is my first time hearing about it. Thanks.
just dont use integration generation navmesh function - more generation action get errors in buld process navmesh - solution create mesh gride - its looking how make roads in map - and in physics object select navmesh and recalculation navmesh - for edit mode navmesh use quadrantic polygons and not use triangle polygons - because triangle create errors for navigation units, if this not help - need create navigation system pathfinding or imitation unit behavior
How does that fix my current navmesh?