jME Plugin NavMeshGen


Could anyone tell me if this plugin was recently added? Some information about it would be nice!

yes it was recently added.

It will generate a navigation mesh.


ok some real info: so it uses the critterAI library to generate the navmesh. It needs a little more polish with the parameters, but essentially just right-click on a node and select generate nav mesh. This creates a spatial triangle mesh that you can use for navigating from all the geometries on that node and its children. The nav mesh will be added as a child to that node.

The actual navigation code is not available yet. However MonkeyZone has some decent nav mesh pathfinding code (it has some bugs) that can directly use this generated nav mesh.

We haven’t announced it yet cause it kind of needs the pathfinding code with it and it needs some work. Normen and I are tinkering with it still.

Oh ok, I’m just asking because I am inteterested in Navigation Meshes, as I’ll need them to acomplish my final course job. I started using Recast, now I’m retrieving the data from the C++ to the Java, wich was harder than I thought it would be.

Right-clicking a spatial sounds easier yeah xD It works quite well, you might have to adapt the cell size and execution timeout depending on your terrain size.

So the plugin is already avaliable it it doesn’t do anything yet :stuck_out_tongue: Although I didn’t see the Right Click → NavMesh stuff in the Scene Editor

It works. It’s only on trunk right now so if you are using the beta SDK you won’t see it.

Right click → Add Spatial → NavMesh

No its in stable but you have to install the plugin. Its in the SceneExplorer

ah cool, didn’t know you moved it over already.

Oh right, of course. I installed the plugin on the Windows but not on the Linux, I’m so dumb. I’ll take a look again when it begins to generate things properly. I’m curious about the data structure you are going to use and how you going to navigate over the mesh.

It does generate it properly. It is just a navigation mesh though, not a pathfinding routine.

The mesh is just that, a triangle mesh. The MonkeyZone code will look at that triangle nav mesh, and build up a data structure from that: triangle objects with links to neighbour triangles.

Well, I was selecting the Terrain Node with a high hill and put to generate the navmesh, and the SDK was crashing. Now I have properly selected a node that contains all terrain, doodads, structures and everything else and properly works.

Sometimes it crashes the SDK, even selection the parent node, even with the same parameters it crashed and, after restarting the SDK, it did not. But besides that, tweaking the parameters a bit generates a good mesh indeed =]

yea it is the parameters that can cause issues, they need to be constrained some more. They are set to constrain to the values that the API specifies, but there are some combinations that are disastrous.

Thing is that it has to stop the thread of the navmesh generation in a pretty harsh way, if the navmesh generation library gets a timeout built-in that shouldn’t be necessary. Probably it crashes after the timeout.

Edit: Oh btw, what do you consider a “crash”? Crashing means the application just quits and you maybe get an error message of the OS.

On my side, crashes instatanly after I press the Finish button.

When I tried to generate a really detailed nav mesh it did timedout, so I extended it. But the crash I said was instantanly.

That sounds like an issue with the graphics driver, did you have the OpenGL window open at that time? Any messages from windows?

Just the Scene Composer windows, if that’s what you asking for. No messages at all, I’m under Linux and the SDK just closed instantanly.

Yeah. So it was open? Then its the OS/graphics really, no way the code in the application has problems w/o just throwing errors. Maybe try changing the look and feel using the --laf option, seemed to remedy some issues on some linuxes. Generally linux (especially ubuntu’s) support for java is a bit wonky right now.

Yeah I’m under Ubuntu currently, as none of my software (except for this case) crashes, nor it freezes my pc, neither one of my drivers just refuses to work or I get a pretty blue screen of death.