Calling All Masters of Bot Pathing...

[Thugdraft]

I've run into a pathing problem in my map that, despite trying various solutions offered by the slew of tutorials out there, I cannot fix. Basically, the bots that spawn in this room do not move at all from the player starts unless they are shot at. Strangely enough, they do move around the room in a team deathmatch game, but still feel off somehow even then.

A couple of notes about the room itself:

1. The entire room is inside of / under a terrain layer (it is a cave inside of a mountain that was made using a sheet of terrain.)
2. The entire room is effected by a gravity volume (GravityZ = -130).
3. On 4 out of the 5 floating rocks in the center is a portal that takes players back up to the arena that is built on top of the terrain layer.

Here's a shot of a debug run as well as shots of the room it self:









Any help at all in fixing this will result in offers of first born children, etc.

Thanks in advance.

[Odedge]

It's hard to second guess why bots won't move around your map.

I believe with gravity volumes, that really changes the way bots move about paths. I think if you have a global gravity that's the same as a volume, they would move better. Try disabling the volume to see if that's better.

With terrain, you should check "bAllowrigidBodyUnderneath". Having it unchecked my be telling the bots they aren't suppose to be walking under terrain (which is normal).

Additionally, bots may not be "motivated" to make the jumps from those floating rocks. But you got to make them move first to find out.

I also find testing with the highest bots are best as you can see what bots can do. Lower level bots aren't as skilled in moving around a map.

[Thugdraft]

OK... Wow... I feel like a moron... The problem is the gravity volume. They moved around just fine when I removed it... You sir, Mr. Odedge, are the man.

Of course, the whole room was designed with low gravity in mind so its now impossible to jump to the portals, etc...

Is there anyway to tell the bots how to properly move around the gravity volume? Its weird because, when the gravity volume was in place, the paths that were drawn seem to perfectly take the lower gravity into effect. Now that the gravity volume is gone, the paths have been reset to only allow movement to the rocks if the bots have jump boots (which makes perfect sense). Is this just a known issue with gravity volumes? Frustrating.....

[Thugdraft]

Here's the new pathing with no gravity volume. The lines leading to the portals are now all light pink (jump boot / translocator paths).

[Odedge]

OK... Wow... I feel like a moron... The problem is the gravity volume. They moved around just fine when I removed it...

It's not a matter of intelligence, just experience.

Is there anyway to tell the bots how to properly move around the gravity volume?

I don't think there is a way for gravity volumes, but don't quote me on that.

Its weird because, when the gravity volume was in place, the paths that were drawn seem to perfectly take the lower gravity into effect. Now that the gravity volume is gone, the paths have been reset to only allow movement to the rocks if the bots have jump boots (which makes perfect sense). Is this just a known issue with gravity volumes? Frustrating.....

Well, what you describe, makes sense. I think it's just an "issue" with gravity volumes. Like I mentioned before, I think if you have a global gravity setting that equals the same as a default gravity volume, the bots navigate it better.

Maybe you can place the rocks a bit closer together, so some bots can double jump to them. I assume they are too far right now without the gravity volume.

[Sly.]

It's not a matter of intelligence, just experience.

^basically this.

I know the first two generations of the Unreal Engine as good as my own home but am a n00b at mapping in UE3. I don't have enough experience in this editor, engine generation and don't know the ideal layout for UT3 maps to make something good looking with good gameplay (yet).

A bridge or some planks to connect the rocks could also look decorative and make bot navigation easier.

[Thugdraft]

Thanks guys... the help is very much appreciated. And yeah, this is definitely my first fully functioning map for the UE3 so the experience issue is very real.

Its a damn shame that gravity volumes break the bots though... The room was very cool to float around in as far as gameplay is concerned. I think I'm just going to build some rock bridges around the room over the lava pit in the middle (sort of like you said Sly) and see how that looks.

I'm finding a couple of other bot retardation areas in my map that involve a double jump and one involving a downwards moving elevator so I may post back here if I can't get those paths working correctly.

Thanks again.

[Thugdraft]

Alright... So I still can't fix the double jump issue. I basically have 4 platforms in the middle of my arena that can be easily double jumped to from the base level.

Here's a quick unlit shot to illustrate the actual jump.



So far, the bots will occasionally use the path nodes wonderfully and double jump as they should. In fact, when this happens, its literally perfect. However... other times they will just run themselves into the side of the platform and not jump at all. Then they back up and run themselves back into the side of it again... repeatedly... and they often ignore enemies as they do this.

Right now, the path from the ground level to the top of the platform is a proscribed path since, before I did that, they didn't try to get onto the platforms at all.

Any advice?

Thanks.

[Odedge]

Any advice?

Yeah... try to think like a bot.

How high is that ledge in which they need to double-jump to? Is it something that can be easily done, or do you have to have the right timing?

Bots want to take the quickest route to get stuff to kill you with and armor/health to help defend themselves as well.

If something is too risky or too far, they may not like that. If bots continually try something and fail, it basically means it's too hard for them to do.

As I mentioned before, lower level bots won't be able to move around the map as much or as well as higher level. For example: I think the bots need to be "skilled" level for them to make a lift jump.

[Thugdraft]

Yeah... try to think like a bot.

Exactly what I've been trying to do!

How high is that ledge in which they need to double-jump to? Is it something that can be easily done, or do you have to have the right timing?

It is VERY easy to pull off. The top of the platform is 64 units up from the place where they should jump from and they have to cross a distance of about 224 units. It seems like you can almost make it with a single jump but you need to double jump to get past the last bit of it, so basically timing isn't an issue... you just have to perform a double jump. That being said, the distance from the dirt to the top of the platform is 112 units... so you have to be standing on the concrete area around the arena to jump to the pillars. I've been trying to figure out if that is the problem actually...

What's hilarious about it is that I've got another, much harder, double jump in the same area where you have to time it almost exactly right to jump across from one platform to another. And the bots pull that one off just fine, every time! Of course they have to be able to make the easy jump up to the first platform to do the hard jump...

Bots want to take the quickest route to get stuff to kill you with and armor/health to help defend themselves as well.

Depending on where they spawn, its very likely that the platforms will be the fastest way for them to get a weapon, so I think I have that part covered.

If bots continually try something and fail, it basically means it's too hard for them to do.

Sure. But they can do the jump perfectly some of the time and then go brain dead and slam themselves against the wall repeatedly the rest of the time. So I know they can do it... I just can't get them to do it consistently...

As I mentioned before, lower level bots won't be able to move around the map as much or as well as higher level. For example: I think the bots need to be "skilled" level for them to make a lift jump.

Yeah, I've been testing on higher skill levels every once in a while for that very reason. It seems like they're less likely to get stuck on these jumps on higher skill levels, but its not that much less... Which makes me think I'm simply doing something wrong.

Could it have something to do with the angle of the jump, or the distance between the nodes? I've moved the nodes around a ton but I could still just not be placed effectively.

Can't thank you enough for the wisdom man. Very much appreciated.

[Odedge]

The distance of the nodes might be an issue. On that point, if there are 2 nodes that are far apart, the bot takes that into consideration. If you had more nodes along that path, that also connect to other paths, the bot might be more willing to take because they have more options.

On your other issue, the terrain might be messing things up for the bots? It's not as smooth as BSP and doesn't provide an "inspiring" path for the double-jump to be made.

[Thugdraft]

The distance of the nodes might be an issue. On that point, if there are 2 nodes that are far apart, the bot takes that into consideration.

Thanks. I'll play around with that tonight.

On your other issue, the terrain might be messing things up for the bots? It's not as smooth as BSP and doesn't provide an "inspiring" path for the double-jump to be made.

The incline of the terrain may also be causing the bots to think that they can get up to the platform node without double jumping... or some other issue like that, as you said.

As far as "inspiring paths" though... I guess I felt like proscribed paths should fix something like that.

For example, the harder, cross-platform jump I mentioned earlier is a proscribed path (in both directions) between 2 nodes (one on each platform), and it works perfectly. When this path was not proscribed, the bots wouldn't attempt it at all.

The double jumps I'm having trouble with are currently set as proscribed as well but only in the direction from the lower level up to the platform (the reverse path from the platform back down is a normal path). Setting both directions to proscribed didn't help and if I clear all of the proscribed paths from these nodes, the bots won't attempt the jumps at all...

[Odedge]

From my understanding. proscribing a path only forces the editor to create one for the bots. It doesn't mean that the bots can or will take it.

[Lord_PorkSword]

Without checking the editor, IIRC proscribing paths tells bots NOT to take that path.
There are also path weights where you make a path 'heavier' meaning that it's a more dangerous route for the AI.

[stevelois]

Indeed, proscribing paths disable the paths, bots won't use it.

[Thugdraft]

Just in case anybody stumbles upon this thread looking for pathing tips... I managed to fix all of my pathing problems after playing around with my path nodes as I've gotten closer to finishing my map. So I wanted to share some of my realizations as far as pathing in case anybody runs into similar problems.

For starters, yes, I misspoke earlier in the thread... It's definitely not Proscribed Paths that you want to use, as they block specific paths. Forced Paths, on the other hand, strongly encourage bots to take that path. I say strongly encourage only because, given certain circumstances (for example if they are being attacked from behind) they won't always take that path, assuming of course that they have other paths available from their current position. I sort of think of it now as a "Highly Recommended Path" as opposed to a "Forced Path".

As far as the problems I was having convincing the bots to perform specific double jumps... What I realized was that I was actually confusing the bots with all of the path nodes that I had placed around the double jumps. Then, when I combined that with trying to use Forced paths to get them to make the jumps, they ended up bugging out pretty badly a vast majority of the time. They also didn't react very intelligently to those portions of the map in general because they were being encouraged, by my forced paths, to do things that weren't really optimal from a combat perspective (i.e. it made them dumber).

At the end of the day, by removing a bunch of my path nodes and placing a few new ones in specific areas, the bots could navigate and understand the layout of the area much more intelligently... Including the double jumps that I wanted them to make in the first place.

I think some noobs (like myself) may initially feel like having more paths in general is a good thing. But I would say that, like most things, its more about quality than quantity.

The thing that ended up helping me the most was to run the map in spectator mode and use the "showdebug" console command to follow the bots around and see how they reacted to my specific path nodes. This way you can figure out exactly which path nodes are causing them to act stupidly and which ones are those "quality" path nodes that seem to help them navigate the map intelligently.

Anyway, I hope this helps people out there and if anybody with more experience than myself has anything to add to the above, I'd love to hear it.

To the people that posted originally, thanks again for all the help.

[Odedge]

Glad you sorted things out. I knew that forcing a path doesn't guarantee a bot to take it, but gives them the option.

There is an art, sort of speaking, to pathing a map. To many nodes, will cause issues as will too few.