AI Libraries for Panda3D



Thanks. I have started setting up bugs in bugs.launchpad.


Added your pursue find to the bug list.

To the community, please feel free to add bugs to this list. Tag them as PandAI for easy searches.


Sounds exciting! I am really interested in looking at this working and the source code.


Nice job Chia_Pet! It would be great if you could post your code to the community so that others can make use of it. And thanks for making use of our libraries.

.csv just means a bunch of comma separated data and is not in anyway an excel format. You can always open it in a notepad or any other text editor for debugging. Excel just recognizes the format and shows it to you in a clean tabular form. So in short the .csv format is not limited by Excel’s limitation. Hope that makes sense.


Well I hope everyone likes the above code. I know I do and again thanks to |Craig| who made this code run in like 2 seconds rather than 6 minutes (origional runtime) lol.

Now one thing you need to know when you can see your terrain the code is done so shutdown and grab your navmesh.csv to use in your real game! (I did it this way so you knew that it didnt just crash on you and i had to load the terrain to make it work with auto number system anyway)


ok new problem, I got the AI working but im not sure what im doing wrong. Ralph can normally move around my terrain just fine using setZ so i figured by making him walk by himself it should be the same but if he is no at 0 height he will fall over i am wondering if this is something to do with PandaAI or maybe my heightmap I generate (as it dosnt include height cause you said to overwrite height). I cannot seem to findout why he will fall when no on level terrain so any advice would be great.

Never mind I figured what i did wrong in the code I made. I designed it for 0 on al z’s so as soon as i went and tried to go above that our code was fighting even though in your demo you overwrite both sets of Z coord’s apparetly this shouldnot have been done. that being said I am working on a fix to my code to work properly for 3d so that this issue dost happen again!


Hi all,

Is anyone else using PandAI with Maya? I’ve followed the tutorial videos but the resulting navmesh.csv doesn’t seem to work. I always get the errors “couldnt find destination” and “couldnt find source.”

Here’s the sequence I used:

  1. Created a 60x60 plane centered at (0,0,0) in Maya 2009
  2. Under INPUTS->polyPlane1 (my plane) I changed the subdivision width and heights to 4 to give me a 4x4 grid
  3. Exported this plane as “env_full.egg” and verified it looked right in pview
  4. Selected three of the center faces and deleted them
  5. Exported this new plane as “env_col.egg” and verified it looked right in pview
  6. Ran C:\Panda3D-1.6.2\bin\egg-trans on BOTH “env_full.egg” and “env_col.egg” to create “env_full_tri.egg” and “env_col_tri.egg,” respectively
  7. Ran “meshgen env_full_tri.egg env_col_tri.egg” to create navmesh
  8. Swapped out my “env_col_tri.egg” and navmesh in the PandAI demo StaticObstacleDemo as a means to test it out. (Note: I repositioned ralph and the destination so that they were inside of my area at the start)

Both ralph and the arrow are definitely inside of the plane, but I get the source and destination errors mentioned above. Any ideas what I’m doing wrong?

Thanks for your help!

Well, I’ve tracked down the source of the problem. Here it is for others to learn from.

The navmesh.csv that’s being generated from my eggs appears to have swapped Length with Height and PosY with PosZ.


Grid Size	3								
NULL	NodeType	GridX	GridY	Length	Width	Height	PosX	PosY	PosZ
0	0	0	0	4.44E-15	20	20	-20	-4.44E-15	20
1	1	0	0	0	0	0	0	0	0
1	1	0	0	0	0	0	0	0	0
1	1	0	0	0	0	0	0	0	0
1	1	0	0	0	0	0	0	0	0
1	1	0	0	0	0	0	0	0	0
0	1	1	0	4.44E-15	20	20	0	-4.44E-15	20

If I swap them by hand, then the navmesh works great.

Root cause:
I was using Maya in Y-Up instead of Z-Up coordinate system. Do’h.


I’m really excited you guys are looking at AI stuff for Panda3D, but I was a bit disappointed by the navigation mesh functionality. It seems as if it’s more of a navigation grid than a mesh, and it looks like it needs to be created manually.

So, I took a look at that Recast project, and ended up getting a small portion of it working with Panda3D. Basically I modified the source of their demo application to export .obj files, which I then imported into Blender, and exported to .egg files. Then I used Panda’s vertex reading utilities to go through the vertices and generate pathfinding data.

I got pathfinding to work pretty well with my own methods brainstormed in Python, but I cut some corners for performance, and it’s certainly not a textbook navmesh implementation. However, it makes me think that someone experienced with the C++ workings of Panda3D could crank out some good code fairly quickly, especially since a lot (if not all?) of it is already done in PandAI.

I think the ability to use automatically-generated navmeshes from Recast is a great feature, and it’s already saved me a lot of time. So, does the current version of PandAI support navigation meshes with different shapes (actually, just triangles)? If not I might look into working on it in C++, but it will take me some time to get up to speed.


Wofire guys also used it: … ion-meshes


@ et1337

Yes you are right it is really a navigation grid.

I think it would be a great idea to get Recast working with PandAI and it was something we really didn’t have the time to integrate into Panda3D but really wanted to.
It is something I have been meaning to work on too. If you wish to try it, let me know if you reach any hurdles on the PandAI side of the code.


Could you please elaborate on which ones you used and an explanation of how.

@ treeform

Thanks for the link.



Here’s my vertex processing code, It’s mostly ripped straight from the manual.

I extract all the edges, and then use them to form “nodes” which are basically triangular areas in the mesh. The edges then link the nodes together, forming a graph which I can traverse with A*.

def _processNode(self, node):
		geomNodeCollection = node.findAllMatches('**/+GeomNode')
		for nodePath in geomNodeCollection:
			geomNode = nodePath.node()
		for edge in self.edges:
			if len(edge.nodes) <= 1:
				# This edge isn't between two nodes, so we don't need to worry about it when pathfinding.
				# But we still need it for determining which node an agent is in.
				edge.navigable = False

	def _processGeomNode(self, geomNode):
		for i in range(geomNode.getNumGeoms()):
			geom = geomNode.getGeom(i)
			state = geomNode.getGeomState(i)

	def _processGeom(self, geom):
		vdata = geom.getVertexData()
		for i in range(geom.getNumPrimitives()):
			prim = geom.getPrimitive(i)
			self._processPrimitive(prim, vdata)

	def _processPrimitive(self, prim, vdata):
		vertex = GeomVertexReader(vdata, "vertex")
		prim = prim.decompose()
		def getVertex(index):
			vi = prim.getVertex(index)
			return vertex.getData3f()
		for p in range(prim.getNumPrimitives()):
			s = prim.getPrimitiveStart(p)
			e = prim.getPrimitiveEnd(p)
			for i in range(s, e):
				v = getVertex(i)
				if i + 1 >= e:
				v2 = getVertex(i + 1)
				edge1 = self.addEdge(v, v2)
				if i + 2 >= e:
				v3 = getVertex(i + 2)
				edge2 = self.addEdge(v2, v3)
				edge3 = self.addEdge(v3, v)
				self.nodes.append(NavNode(edge1, edge2, edge3))

To determine which node an agent is in, I just do a dot product from the agent’s position to the center of each of the three edges. If all three dot products are positive (or negative, I can’t remember), the agent must be inside the node. I do some other stuff for vertical testing as well. It’s all in the A3P repository.


I hope it’s my search skills failing, but I haven’t been able to find a version of the Navigation Mesh Generator for Linux. In the download section of the PandaAI website there’s only Windows exe and source. Is it included in Panda 1.7? And if so, under what name and/or in what directory (of it’s not /usr/bin)? Thanx in advance.



You are right. There isn’t one. But to aid you I have re-factored some of the code and have the source code for the Mesh Generator available to be downloaded at : (MeshGen_Linux)

Unfortunately, I don’t have an executable ready to use, so you will have to build it in your version of Linux using this source code.

The executable should work the same way as the documentation states.

Do let me know if this works fine.


Thanks for the reply. I’ve actually managed to build it in the meantime (had to recall how to use g++, hehe) from the source on the PandaAI download website. It seems to work, but if I happen to hit a wall with it, I’ll try your version.

Still, I think it should be included with Panda itself. It’s kind of a non-sense for PandaAI itself to be included, but not the most important tool to make full use of it.


Is there any progress on the Blender side of things? I’ve tried making the most simple possible navmesh (a sudivided plane) and failed completely, with the character ending up totally confused with the map (as expected given the previous post on the subject). Is there any chance this will get resolved soon? I have no access to neither Max nor Maya and I need PandaAI, so it’s a rather huge problem for me…


Cool. Good to hear you got it working. I will leave this code up anyways since it is a cleaner version and have removed any panda dependencies (since the mesh generator really doesn’t need any).

Sorry, the blender support is still in progress due to time constraints.

Try to use a trial version of Max or Maya till then.


I fully understand that time is a problem, and I really appreciate your work so far. However, is it possible to estimate how long it will take to get it to work? I’m only asking this because I’m working on a rather big project (in which I’m planning to make extensive use of PandaAI), and need at least some indication, so that I can plan my work. Don’t get me wrong, I’m not trying to hurry you up, I just need to know where I’m standing. I hope you understand that.

Unfortunately I really can’t use Maya nor Max, trial included. Max is not an option because I’m on Linux, and I don’t seem to currently meet the requirements for Maya.

Thanks very much.


Sure. I understand.

Give me a couple of days(upto a week) to get back to you on this.



Thanks very much, I really appreciate it.


@ coppertop

I am sorry but I don’t think we can give a definite answer on the Blender support as of now due to time constraints and lack of our knowledge on the EggData side, which I have been researching.

I hope I can get more time to spend on this apart from my other responsibilities (as I am not full time on PandAI anymore). Please assume that there is no Blender support as of now. I hope you still can use other parts of PandAI.

I will post it up when it is fixed.


That’s a shame, but I fully understand the situation. And I will definitely make use of the rest of PandaAI. Thanks.


Good News!!!

We are excited to say that the PandAI pathfinding solution now supports Blender. We have created a separate mesh generation tool for creating a navigation grid from a plane made using Blender. You can download the required files from here:

In the above zip file you will find the following:

  1. A ReadMe file which explains how to use the tool.
  2. The python script required to generate navmesh.csv from Blender full and collision planes.
  3. Sample planes created in Blender which were used for testing.

A few IMPORTANT things:

a. Make sure your the full and collision planes that you make are on the ‘X - Z plane’ of Blender.
b. This is for planes created using ONLY Blender. For Max and Maya please continue to use our previous meshgen tool.

Here is a video of pathfinding working with planes created in Blender:

NOTE: The lag is due to a lot of spheres being rendered as nodes.

Lastly, it would be really helpful if people using PandAI and Blender could give us feedback about this new tool we have provided. If you come across any bugs or discrepancies please report it in this thread.

Thanks a lot for your support!

  • Team PandAI.

Help with Egg File Parsing in Python