Pathfinding Update Week 23

This was an interesting meeting. I met Horatio, a tiny polar bear AI character. I think Horatio is an excellent example of what Pathfinding can do. He/she is an awesome little polar bear.

Cute Horatio

Horatio will obey commands like ‘come’ and ‘sit.’ Plus Horatio is soooo cute. This is one of Motor Loon’s creations if I understood correctly.


Lorca Linden says they have had a few bugs in the ADITI Pathfinding packages during week 23.

Show & Tell

A bit of a show and tell was done. Horatio and a Rottweiler, named Killer, were shown. The Rottweiler version was using an older LSL AI type script. Horatio was using AI based in Pathfinding. Horatio is quick. Fun demo.

Pathfinding Viewer

The current version available today is: Second_Life_3-3-2-259040_ProjectViewer-Pathfinding. A link is in the left column here.

Lorca is looking for people that have played with the viewer to give feedback. One of Falcon’s questions is whether the viewer has a good work flow for retrofitting existing regions. While Lorca won’t give dates, the release of Pathfinding is getting close. So, get your feedback in or live with what you get.

Sandry Logan has found the workflow reasonably workable. Still updating a region was described as a grind, which is understandable. But, the Lindens are working to make it as painless as possible.

Stinson Linden has built most of the Pathfinding interface in the viewer.

Aerial Pathfinding

In response to a question on aerial Pathfinding Falcon Linden said, “Someday it might be possible to provide aerial Pathfinding, but issues like banking (should characters bank? how?), dynamic updating of the nav volumes, and takeoff/landing make it hard.”

Build Panel Changes

Rex Cronon thinks … the build window should have a new tab with all the properties regarding pathfinding.

Falcon answered, “That’s harder than you’d think. Instead, we’ll provide a right-click option to open selected in linksets/characters floater as appropriate.” I suspect that the Build Panel is already too overloaded and the Lindens are unlikely to add another tab to the panel.

I do think there should be a button or some other hint of how to get to the Character and other Pathfinding settings in the build panel. It seems like a logical path. I know I would expect that and I suspect other people in SL would make the same assumption. Object editing is in the Build Panel (Ctrl-B) and one does not have to use the top menu to get to it. In fact I seldom use the top menu for anything other than the stop animations and landmarks.

But, I understand that a crowded Build Panel can be intimidating and people do over look things they don’t understand. So, a button in the confusion may not help that much.

Falcon exemplifies the problems well saying, “We also think that in German you shouldn’t have to wait for the names of the tabs to scroll by and that the build panel shouldn’t take up the entire viewport. But we can’t have everything we’d like, just like you’re not gettin’ rainbows or ponies.


TriJin Bade reports Pathfinding performance is good in regions TriJin manages. I think we still have a goodly amount of debug code in the Pathfinding  code.


llGetStaticPath() is a new LSL function coming to Pathfinding in the next release, which we should see in week 24.  This function will use Havok to return a list of waypoints between ‘start’ and ‘end’  through which a character of effective radius ‘x’ can pass.

This is a feature a number of creators have been asking for. It is great that the Lindens are providing it. I think I’ve hear the phrasing, ‘Don’t Hold Your Breath’ applied to requests for the feature. So, this is a nice surprise.

Falcon says, “llGetStaticPath will NOT take into account any object not marked as static. I envision three main uses for llGetStaticPath.

  1. In attachments in a fully Pathfinding region (where everything important has been marked walkable/obstacle)
  2. As a fallback method for Pathfinding objects in Pathfinding-disabled regions. (yes, it will work in pathfinding-disabled regions)
  3. For use with llSetKeyframedMotion() to determine waypoints

Mæstro Linden  says, “I guess it would be correct to say that the list of points should roughly match what the viewer’s “Test Path” shows.” Falcon agreed.

Some of the restrictions are: Your start and end points must be within a character radius of the Navmesh. That brings up a bunch of questions about the PF Disabled regions… Falcon explains, “llGetClosestNavPoint(start, [GCNP_RADIUS, radius]) must return a hit. So if your radius is small, you should use llGetClosestPoint first with a bigger search radius to find a better start/end.

The last element in the returned list of points will either be: 0 if the path is good or it will match a PU_FAILURE_… constant (in which case the list will be size 1).

For now there is no cap on the list size, other than memory available. If that proves to be a problem they will add a cap.

Learning Pathfinding

Any1 Gynoid is providing training in-world for those wanting to learn how to script Pathfinding.

The Lindens are making a list of the regions in the Pathfinding Beta. Any1 will soon have it available for students, provided the Lindens get Any1 a copy, which they are planning to do.

Mæstro Linden points out the snack sandbox regions in the main channel are PF enabled.

Lorca announced they also plan to move more of the public sandboxes onto the PF channel next week on AGNI. Premium sandboxes are running the PF enabled code.

Expect to see some Premium Member Pathfinding pets or other critters offered soon.

Joining the Pathfinding Beta

Next week will likely see the last set of additions to the Pathfinding Beta. So, if you want to get in on this email to have your region added.

6 thoughts on “Pathfinding Update Week 23

  1. When are these pathfinding meetings, cause I can tell you with total certainty, that they are missing a bunch of problems. 1 of those being that if an item on your sim is not part of the navmesh, then you can’t change it’s properties and the coding in that object will never be able to work. Did they ever even announce these meetings in the forums. I was part of the beta testing and never got any emails about pathfinding meetings. No, I do not think Pathfinding is anywhere near ready for primetime. Personally, I don’t know if it ever will be. There is just no real way in hell that some average landowner is ever going to figure out the navmesh and I don’t really see how they are going to make that easier. Pathfinding is totally awesome for a themed sim or rpg sim, but not for the vast majority of sims on the grid, IMHO.

    • Pathfinding Meetings: User Groups

      You are mistaken about #1.

      There are about 65,000+ concurrent users most days during Linden working hours. There are less than 30 people that attend PF meetings, that’s 0.046% of the peak daily concurrent users and even less of the total unique users per day. We don’t hear about GM moving to China and their customers pay far more for their products and services than we do for SL services. Plus they are still into US tax payers for billions. It seems a bit arrogant to me for people to think the Lab’s software engineers will take more time away from their job to talk to customers than GM engineers do.

      While you may be right about whether PF is ready, I suspect it is more about someone not understanding Pathfinding than it is the state of Pathfinding. If you had been reading my articles on PF, you would know I’ve already been down that road.

  2. Here is what I’ll say to that – Out of that 65k, how many people earn enough in SL to make a full time living and how many of those people goto the meetings? As I have been to many different meetings, I’d say, not many, if any. It would do LL well to seek those people out and ask them directly, or even better, pay them to test their stuff and give feedback.

    • The Lab is constantly using game testers to test user interfaces and and various ideas. Plus, in the meetings they ask for help and feedback. The last few PF meetings have had such requests. Plus they have about 140 or so regions in AGNI that are Pathfinding Beta test regions. Most of these are volunteered regions. So, they have a good idea what people are experiencing.

      So, what you think would be a good idea for the Lab to do is made from a place lacking information and awareness of what is going on. So, don’t be surprised that they don’t hear you. Your take that they are not getting feedback and input from the less well informed is correct. However, that does not mean they aren’t getting feedback and aren’t talking to SL users.

  3. Thanks Nalates – this is all sounding very positive, I’m looking forward to setting up a navmesh on our estate.

    Was Horatio able to orient himself to the direction he was moving in and adjust his walking pattern when hitting an obstacle? He certainly looks cute :).

    • Horatio did orient himself. Pathfinding AI Characters face the direction of travel. They avoid obstacles, avatars and moving prims. There is some jitter when they are in a crowd. PF is not perfect. One of the things I had hoped for was the ability to bank traveling characters through turns. I made a Serge (from SiFi show Caprica) that I wanted to bank through turns. But, script feed back and a rotation from the PF functions have limits and banking is not possible for now, or I have not figured it out.

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