reported 2.8 AI Ground Unit 'On Road' Pathing completely broken; even worse if you use HOLD/GO on ground units.

[TEMPEST.114]

I have a convoy sent to ON ROAD. I am using two flags and the radio menu to stop and start them, using an advanced Trigger Action of HOLD /? with a STOP CONDITION of the GO flag being true.

Nearby this convoy I have a CLIENT helo with 14 infantry spawned stationary right next to the helo for boarding. 

As soon as the mission starts the first unit in both groups goes for an extended walk / drive about - despite the infantry having no waypoint to go to prior to embarkation and the front car of the convoy going in circles in the opposite direction of the first waypoint.

The first infantry stands on the opposite side of the helo from the stationary other 13 members of the group and runs around in a small circle forever - at least until instructed to embark.

 

The car eventually drives towards waypoint one and the ones behind eventually get the idea to follow, but then when I issue the stop command, instead of them all stopping, they drive OFF ROAD through gardens, across railway lines and other roads that weren't on the waypoint list in order to 'stack closer' to the lead vehicle, but then they screw that up and break into about 3 groups, some not moving, some getting stuck in the scenery and some eventually getting closer to the lead vehicle than the default starting spacing forced upon us all.

When you send GO again, the front ones follow the waypoint on road (mostly) but the back ones don't know what to do or where to go, eventually the start moving and then when you say stop again they cross country, through buildings, gardens, car parks and everything and again, get stuck.

HOW is this correct and acceptable? If they were all set to OFF ROAD, whilst still utterly awful, going direct to 'stack up' (which they still shouldn't do) would be slightly more acceptable, but when they are constrained to 'ON ROAD' this type of behaviour shouldn't even be possible. 

Here is a video of it on YouTube showing just how broken and screwed up the pathing is:

https://youtu.be/8H3vcy--B-g

And how unreliable it is when you have a convoy and need it to stay together as it moves into the target zone. You can't even trust your units will make it there to be fighting efficient!

 

[Rudel_chw]

This looks more like a rant/complaint than a proper bug report ... how do you expect the developers to attempt to study and reproduce the issue in order to find a solution if you don't bother to attach the mission or a track file? are they supossed to recreate the mission file starting from your video? 

[Grimes]

There are two facets to this. One is an easy fix and the other is similar to an existing bug report for ground AI and the hold task. 

1. For one reason or another the ground AI always face the direction of their next waypoint even if starting on road and if that waypoint is on road. As you can see in the video all of the ground AI drive south slightly and then some chaos ensues due to pathfinding issues in object dense locations like cities. Which is a whole subset of other issues. Anyway its an easy fix by adding a waypoint on that road or by ticking the "Initial" box to force AI to orient with the road. If you add a waypoint then you'll note that the rear of the convoy will drive west-ish toward it, but probably won't meander because its an empty field with no obstacles. 

2. For the hold task the AI want to stop where they are expected to be in a given formation. The bug being that they will go off road to get there. Due to the chaos, in general the unavoidable concertina effect of convoy movement, and the road layout results in the AI near the back of the convoy will be out of position. Said AI then make a B-line for that coordinate rather than following the road to get there. Then the aforementioned issues with AI driving through cities kicks in. 

I updated the existing bug report. In it they did the same thing but the difference was they formed a line based on the heading of the leader, so you got results where there is a line of AI stretching off road. That part appears to have been accidentally fixed, but the "going off road to get there" is still around. 

[Rudel_chw]

1 hour ago, Grimes said:

There are two facets to this. One is an easy fix and the other is similar to an existing bug report for ground AI and the hold task. 

 

Thanks a lot for explaining this, I will take note on my FAQ and be sure to apply your tips on my missions when needed. 

[TEMPEST.114]

What about the first unit doing stupid things?

In my video you can see the first infantry goes for a walk bout and then later stands on the other side of the helo and spins in a small circle forever. That’s clearly a crazy bug.

 

same for lead car which turns around, goes off road and drives around car 2 

neither of your explanations account for this new issue since 2.8  

 

And regardless, they shouldn’t cut across country - it’s clearly not working as not all manage it and get lost/stuck, but if they are set to 'on road', they should STAY on road. 

Edited December 19, 2022 by Elphaba

[TEMPEST.114]

INITIAL didn't work.

Unit 1 of group still turned around drove (walked) circles around and ended up out of position and facing the wrong way (car) or walking in circles perpetually (infantry).

[Grimes]

Donno about the infantry since the video didn't really focus on them and I can only do so much to recreate a mission without a miz or track file. It is a moot point anyway due to there being units from mods in the mission. The unit type does matter because units have different sizes and turning capabilities. 

6 hours ago, Elphaba said:

neither of your explanations account for this new issue since 2.8

What? I said the units are oriented south, object avoidance kicks in, and thats why there is some general weirdness with their pathfinding. 

In 2.7.18 the initial setting doesn't work, but in 2.8 it does. In both version you can insert a waypoint for the AI to be pointing toward. Which allows for the AI to start facing the direction down the road and generally avoids the problems with the off road collision detection. 

6 hours ago, Elphaba said:

And regardless, they shouldn’t cut across country - it’s clearly not working as not all manage it and get lost/stuck, but if they are set to 'on road', they should STAY on road. 

Yes and I said that was a bug. For reference this is what they do in 2.7.18 when told to hold. They want to form a line based on the heading of the lead unit. In 2.8 the points they want to park at is correctly on the road, but don't follow the road to get there. I'd imagine the only change made is that they corrected the point where to go and nothing changed with how the AI try to get there. 

 

[TEMPEST.114]

1 hour ago, Grimes said:

Donno about the infantry since the video didn't really focus on them and I can only do so much to recreate a mission without a miz or track file.

You can see the single lead infantry unit spinning on its own broken away from the rest of it's stationary group, in the video at 01:46+

Yes, these are mods (liveries actually for the M4 soldiers) because DCS doesn't have civilian or police uniforms, nor does it have civilian aircraft/cars/police/unarmed units from which to build a CAS style / Rescue mission. Perhaps if DCS did, people wouldn't need mods so much to make missions that aren't just blow X up or shoot Red Y? 

But as they're just liveries and not anything more than that, that shouldn't discount them.

I'm happy to send you the miz, but as you require all the mods to be removed then it would be pointless. I'd hoped a video capture would suffice. Although I have a convoy in another mission that uses standard DCS assets and it's doing the same craziness. 

And I can make another to show that the initial heading is due East along the road and yet the LEAD UNITS of both the vehicles and infantry STILL TURN AROUND AND DO STUPID STUFF by themselves, like crash into and explode DCS AI parked cars or crash into Unit 2 and 3 before facing the wrong way and stopping or walk for miles before returning and spinning on the spot...

Would that help, or could you trust me on that? There is no scripting going on that's affecting these, except for the STOP and GO commands in the ME Trigger system.

Why is it that the spacing we can't change for a convoy (to make them closer or further apart) but when you issues a HOLD action, then the spacing reduces a great deal? Is that a separate bug or part of the broken pathing algorithm that's already known? Because the whole thing about convoys is that for some strange reason ED forces a spacing that we have no control over and it almost always sticks to that - unless given the hold command...

[Grimes]

Yeah you can see the infantry doing something weird, but its a blob on the map. It isn't unheard of for AI to do something strange purely out of weird object placement, but I can't tell what is going on, and that is where a mission file would be really helpful. Yes videos can provide some insight into behavior, but seldom as the primary source. Without the mission I had to figure out which map it was on and the location based on different clues. Thankfully the city name "Arizona Village" and a river were visible so I could narrow the search to southern NTTR. However attempting to recreate the mission has its own flaws like not precisely matching unit placement, waypoints, tasking, and other parameters. 

At the point of coming off as rude its why you see people ask for a track or a miz file. At best the same behavior happens on our end and its an easy bug report. At worst we can see the general idea of what might be happening and experiment on a mission where it has been known to occur. 

5 hours ago, Elphaba said:

And I can make another to show that the initial heading is due East along the road and yet the LEAD UNITS of both the vehicles and infantry STILL TURN AROUND AND DO STUPID STUFF by themselves, like crash into and explode DCS AI parked cars or crash into Unit 2 and 3 before facing the wrong way and stopping or walk for miles before returning and spinning on the spot...

Would that help, or could you trust me on that?

By all means if you get the behavior to occur with default units then upload the mission. But I was under the impression the AI are intending to drive west...

https://gfycat.com/singleannualcarp

4 hours ago, Elphaba said:

But as they're just liveries and not anything more than that, that shouldn't discount them.

nullLiveries won't change AI behavior, but there are clearly unit mods in the mission. You can safely upload missions with missing liveries anyway. My game will just choose something by default. Mod units are another issue and I can't debug a mission where they are the source example of a bug. If there were static object sandbags someplace that were left in I'd just mod the editor or delete the file requirement to load the mission. Hence why I've asked for a file with default units showing the problem. 

[TEMPEST.114]

3 hours ago, Grimes said:

Yeah you can see the infantry doing something weird, but its a blob on the map. It isn't unheard of for AI to do something strange purely out of weird object placement, but I can't tell what is going on, and that is where a mission file would be really helpful. Yes videos can provide some insight into behavior, but seldom as the primary source. Without the mission I had to figure out which map it was on and the location based on different clues. Thankfully the city name "Arizona Village" and a river were visible so I could narrow the search to southern NTTR. However attempting to recreate the mission has its own flaws like not precisely matching unit placement, waypoints, tasking, and other parameters. 

At the point of coming off as rude its why you see people ask for a track or a miz file. At best the same behavior happens on our end and its an easy bug report. At worst we can see the general idea of what might be happening and experiment on a mission where it has been known to occur. 

By all means if you get the behavior to occur with default units then upload the mission. But I was under the impression the AI are intending to drive west...

https://gfycat.com/singleannualcarp

nullLiveries won't change AI behavior, but there are clearly unit mods in the mission. You can safely upload missions with missing liveries anyway. My game will just choose something by default. Mod units are another issue and I can't debug a mission where they are the source example of a bug. If there were static object sandbags someplace that were left in I'd just mod the editor or delete the file requirement to load the mission. Hence why I've asked for a file with default units showing the problem. 

I misspoke (typed?) I mean I had them set to INITIAL west but the lead still turns EAST for no good reason. 

Here is the mission file with all the liveries / mods / scripting removed.

AndTheHorseYouRodeInOn.miz

IT DOES THE SAME STUFF; just lke I said - the liveries and the civilian car models vs ED military vehicles have NO EFFECT on the broken pathing.

Nor the stupid behaviour of the first unit in ground units. 

I don't have a 'track' file, but if you run this multiple times you'll see it does something different every time, but always stupid (blowing up parked cars by turning away from INTIAL heading when not instructed to move) and Infantry going for walkabouts for no reason. 

[Grimes]

Case in point with something critical being different, you started the convoy with a hold task while I didn't notice that and never added it in my attempt to recreate it. Thankyou for posting the mission file it has made things easier to diagnose. 

It is a little weird because with your mission it took about 5 minutes to test a few theories and find a possible solution. Then followed by at least 20 minutes trying to re-create it on another map and completely failing to do so. Such is DCS AI and who knows what other contributing factors.

What I can gather is that speed appears to be a heavily contributing factor. This worked on your mission but not in another test mission I created for that specifically, but simply adding a waypoint at a slower speed prevented the convoy lead from meandering. For one reason or another that change didn't apply to my isolated test mission. I ended up moving the hold task to a waypoint just after the start in order to show the problem. Which might be a more reliable solution until the bug with hold on initial waypoint is addressed. 

https://gfycat.com/welcomelimitedlabradorretriever

As for the infantry, I'd have to experiment with it some more because I don't use ED's built in tasks for troop transport. Best guess is that the embarking task isn't treated as a hold task and they are actively looking for a transport which requires some initial movement. 

[TEMPEST.114]

4 minutes ago, Grimes said:

Case in point with something critical being different, you started the convoy with a hold task while I didn't notice that and never added it in my attempt to recreate it. Thankyou for posting the mission file it has made things easier to diagnose. 

It is a little weird because with your mission it took about 5 minutes to test a few theories and find a possible solution. Then followed by at least 20 minutes trying to re-create it on another map and completely failing to do so. Such is DCS AI and who knows what other contributing factors.

What I can gather is that speed appears to be a heavily contributing factor. This worked on your mission but not in another test mission I created for that specifically, but simply adding a waypoint at a slower speed prevented the convoy lead from meandering. For one reason or another that change didn't apply to my isolated test mission. I ended up moving the hold task to a waypoint just after the start in order to show the problem. Which might be a more reliable solution until the bug with hold on initial waypoint is addressed. 

https://gfycat.com/welcomelimitedlabradorretriever

As for the infantry, I'd have to experiment with it some more because I don't use ED's built in tasks for troop transport. Best guess is that the embarking task isn't treated as a hold task and they are actively looking for a transport which requires some initial movement. 

 

I'd added the hold task to try and get lead to stop going off on it's own. And I needed to set a high speed for timing purposes for the rest of the units.  Sure, I could add a very close by initial 1 waypoint at 20mps and then go 'full throttle'. 

If it was that difficult and the vagaries of DCS AI are such that it's unreliable - that itself is a bug/reason it needs a *serious* re-write and fix. 

[Grimes]

Lead unit on hold task behavior is now reported. 

[TEMPEST.114]

On 12/20/2022 at 12:22 PM, Grimes said:

As for the infantry, I'd have to experiment with it some more because I don't use ED's built in tasks for troop transport. Best guess is that the embarking task isn't treated as a hold task and they are actively looking for a transport which requires some initial movement. 

Then why is it usually only the lead unit that goes off on one, and most just stay put where placed?