gameplay-ai

[gentle widget]

It gets stuck in the "Move To Location" state

It works all of once, it just never exits the state

[misty wharf]

Are you sure the move to target location task actually finishes at some point?

[gentle widget]

Uh

Hm... actually it might not be

I'll past the task code, opening IDE right now.

90% sure I'm doing something wrong cause it doesn't work lol

{
    FMoveToTargetLocation_InstanceData InstanceData = Context.GetInstanceData<FMoveToTargetLocation_InstanceData>(*this);

    if (AEnemy_AIController* Controller= InstanceData.Enemy_AIController)
    {
        if (APawn* Pawn = Controller->GetPawn())
        {
            UAIBlueprintHelperLibrary::SimpleMoveToLocation(Controller, InstanceData.Location);

            /*
            if (Pawn->GetActorLocation() == InstanceData.Location)
            {
                const FStateTreeTransitionResult TransitionResult;
                ExitState(Context, TransitionResult);
            }
            */
            return EStateTreeRunStatus::Running;
            
        }
    }
    
    return EStateTreeRunStatus::Failed;
}```

I commented out a test case for exit state because that didn't work either.

I'm guessing I might need to change that return from Running to Succeeded? I thought that would also make it stop executing though

Oh and move it into the scope for that if statement checking locations

[floral compass]

I do not use the Tick function so I don't know for sure, but at least the "EnterState" will keep you in that state if you return "Running".
Anything else will immediately move to the next state (or whatever you have set up)

[gentle widget]

For the movement logic, EnterState was not working. The AI Actor wouldn't move at all

I had to use Tick to get it to actually move

[floral compass]

I mean

Override the EnterState and return Running

[misty wharf]

Success and Failure will end the state

[floral compass]

And do the MoveTo on tick

[gentle widget]

Oh I see

[floral compass]

Also there are some bools you might wanna check

[gentle widget]

{
    FMoveToTargetLocation_InstanceData InstanceData = Context.GetInstanceData<FMoveToTargetLocation_InstanceData>(*this);

    if (AEnemy_AIController* Controller= InstanceData.Enemy_AIController)
    {
        if (APawn* Pawn = Controller->GetPawn())
        {
            UAIBlueprintHelperLibrary::SimpleMoveToLocation(Controller, InstanceData.Location);

            if (Pawn->GetActorLocation() == InstanceData.Location)
            {
                return EStateTreeRunStatus::Succeeded;
            }

            return EStateTreeRunStatus::Running;
        }
    }
    return EStateTreeRunStatus::Failed;
}```

[floral compass]

    /**
     * If set to true, the task will receive EnterState/ExitState even if the state was previously active.
     * Generally this should be true for action type tasks, like playing animation,
     * and false on state like tasks like claiming a resource that is expected to be acquired on child states.
     * Default value is true. */
    uint8 bShouldStateChangeOnReselect : 1;

    /** If set to true, Tick() is called. Not ticking implies no property copy. Default true. */
    uint8 bShouldCallTick : 1;
    /** If set to true, Tick() is called only when there are events. No effect if bShouldCallTickState is true. Not ticking implies no property copy. Default false. */
    uint8 bShouldCallTickOnlyOnEvents : 1;

    /** If set to true, copy the values of bound properties before calling Tick(). Default true. */
    uint8 bShouldCopyBoundPropertiesOnTick : 1;
    /** If set to true, copy the values of bound properties before calling ExitState(). Default true. */
    uint8 bShouldCopyBoundPropertiesOnExitState : 1;

    /** If set to true, TriggerTransitions() is called during transition handling. Default false. */
    uint8 bShouldAffectTransitions : 1;

    /** True if the node is Enabled (i.e. not explicitly disabled in the asset). */
    UPROPERTY()
    uint8 bTaskEnabled : 1;

[gentle widget]

Refactored to this and it still doesn't work so I'll try some more

[misty wharf]

You could also just use the delegate-based moves instead of SimpleMoveTo

If you make a UObject-based ST instance data, you can bind delegates to it

[gentle widget]

I may have to do this. Doing more debugging shows the AI Actor is not reaching the target location exactly, so the succeeded case is never being called

Is there a built in movement delegate you're referring to or would I just make my own on the actor class?

[misty wharf]

look at how stuff like AITask_MoveTo are implemented

[fathom dome]

Could anyone here share some links that expand on how to read visual logger info?

what I'm finding is leaving me very... wanting

[misty wharf]

the vlog stuff is kinda contextual, you have to read what it says and understand it

bit difficult to say exactly what everything you might see can mean since there's a lot of different systems that log into it

but in general, yellow=warning, red=error

[fathom dome]

I see

the single lines

that's just a tick of logging right?

[gentle widget]

Also the vlogger is like a timeline, you scrub through it. Something I didn't realize when I first started using it lol

[misty wharf]

Yeah the vertical lines in the vlog timeline are the points in time when something was logged

[fathom dome]

ok

when it comes to Ai, like the move to node

it will tick multiple times saying something like "moving directly to goal"

is this telling me that it just picked up a new instance of attempting to move

or just the same instance over time?

does that question make sense?

[misty wharf]

if it logs that a lot it kinda sounds like it might be restarting the move again as a result of a new move request

but I recall if a new request comes in, it should say something about it and aborting the previous request also

[fathom dome]

ah ok then if that's the case it may be the same call

this is what i'm trying to interpret

specifically the top line which is all blue ticks (the second line is an actor outside of the navmesh so fails every time)

this last segment to actor visual thing

is that where the actor wants to be or where it is?

or is it the red arrow?

[misty wharf]

I think the red arrow is where the moving actor was at the time

[fathom dome]

ok

that makes sense

[misty wharf]

You should be able to see it if you look at the different logs when it's moving, the red should move with it then

[fathom dome]

ok that makes sense

I'll try to do that

I'm also trying to figure out how to see the target its moving to

is there a button to see these visuals as its logging?

instead of just as snapshots?

[misty wharf]

iirc the gameplay debugger has a navigation category which shows the navigation stuff as it occurs

' should open that one when you are in PIE

if it doesn't enablegdt in console opens it

[fathom dome]

ah yeah

i guess I was trying to see it after though

but that's ok

neoexcidious gave me some advice but i'm not really sure how to execute on it

I think I need to understand these tools better

ok after looking close at how the behaviour tree runs I don't think it is having issues of overwriting ongoing tasks

[uneven cloud]

I actually got an interesting recruitment email from id that I was considering before the last round of Microsoft layoffs. Glad I didn't pursue it.

You want to block pathfinding. How you do that depends on if you are using C++ or not.

Well you are using pathfinding which is constrained to the ground.

[dire fable]

we're using c++

[uneven cloud]

You should not be requesting a move on tick.

[uneven cloud]

The first go to is to lock logic. The BT and path following component both have functions to lock the logic.

[dire fable]

I don't want to lock logic, I still want the BT to run

because movement can be blocked, but the AI can still attack or rotate

[uneven cloud]

You can lock the path following component without locking the BT

[dire fable]

i tried to search but i didn't find where

do we have a method to pause path following ?

[uneven cloud]

LockResource

[dire fable]

[gusty maple]

I'm calling Ai MoveTo every tick, is this bad for performance? Should I just use add velocity for basic enemies?

Im talking 50-100 running at once

[dense owl]

Build, profile, adjust

There are optimizations you can make if your perf suffers

[gusty maple]

Is there an alternative to AI MoveTo that doesnt bug out with launch character?

wait nvm

[tawdry zephyr]

Hey @crystal hatch I can't DM you since the server changes. You put me onto a good contact for the animation stuff and we got fixes in for 5.4.

I'm using the Mutable plugin in production and the initialization path is undocumented and broken. I've made a plugin that handles initialization but a lot of this should probably be incorporated into the base plugin. The plugin works with all net modes. I've made a few PRs too since you literally can't initialize in a sane manner without it.

I do have UDN access but we don't use Mutable for work so probably better not to use it for that.

Could you pass along my plugin to see if they want to use it as a resource for fixing or improving Mutable?
Links:

https://github.com/Vaei/MutableExtension
https://github.com/EpicGames/UnrealEngine/pull/11859
https://github.com/EpicGames/UnrealEngine/pull/11864
https://github.com/EpicGames/UnrealEngine/pull/11870

[undone stream]

So what i have to use?

[uncut rune]

Is it ok generally to use 1 blackboard for all different kind of characters and different behavior trees? Or should I create own bb for each even if they share some keys, but other characters don't use them and use others?

[gentle widget]

EnterState didn't work, tick was the only thing that worked.

[gentle widget]

Tried to implement this but I can't figure out how to bind the delegate for OnMoveFinished. Just keep getting errors or making my IDE mad.

[misty wharf]

You would need to make your instancedata an Uobject and then bind to that

there's some builtin ST tasks which do this

[floral compass]

I think making use of the hierarchical feature of blackboards in UE is a good approach
Have 1 root blackboard that has very generic info
Then derive more blackboards from it that extend with more specific info

[gentle widget]

Finally, got it -almost- working.

Basically rewrote the StateTreeMoveToTask to do it, albeit a slightly simpler version.

Just kidding, I broke it again 😄

[uneven cloud]

Why didn't EnterState not work? Right now you are requesting a move every tick, which not only doesn't work it's very bad for performance.

[uneven cloud]

The simplest way is to use move directly towards

[dim lynx]

hi, how can I take the point where the AI ​​goes without setting it in a variable?

is this even possible?

[uncut rune]

Anyone has time to brainstorm idea with me ? 😄 Sorry for bad pictures I'm not artist. I'm trying to create behavior tree for ranged unit that when commanded to attack, will go to attack range and attack. After thinking a little, I think I have to use EQS to make that and I would just make the ''location to move'' based on furthest distance from the enemy and the shortest path to that point from my unit. Is this correct approach?

[frigid plinth]

can yall help me with a problem im having.... I have a mesh as the floor and its all one mesh but the NPC can only walk on one side????? I have 2 nav meshes for both sides so i have no clue on to why They can attack but they dont walk on the one side but they can on the other

[misty wharf]

If you are using pathfinding you could just have it move to the enemy and if it reaches attack range have it stop moving any further

[uneven cloud]

What is wrong with having variables? That's the basics of programming.

[uneven cloud]

Shortest path is usually unnecessary. You can use the dot product for more intelligent location selection.

[deep grove]

Are you wanting to send it to another actor? You could send it via an interface or event dispatcher depending on what and how you want to send that data or you could use a variable there's nothing wrong with them like Luthage said lol

[lament bramble]

Hi, how to make an AI that can walk on walls and ceilings. I want to create an AI spider. Thank for your help

[dense owl]

Good question. Not sure if you can do this with anything built-in

[floral compass]

I wonder if you could change the direction of the navmesh internally somehow? Surely it's doing a floor trace/scan downwards somewhere, no?

[dense owl]

I guess, but normal navigation is tied into the CMC/PMC so not sure how deep you’d have to go to achieve this

[floral compass]

True, down is the assumption across the entire nav system.
But for a spider (assuming no obstacles on the walls) you could do something manual with BP instead maybe?

[dense owl]

I mean, yeah. You could hack your way around it, turn the mesh upside down, and use a trace to set its relative location so that it looks like it’s walking on the ceiling

The old smoke and mirrors can work, depending on how contained the scenario is

[uncut rune]

Would you mind telling a little bit more details? Do I still use EQS for that or it's something else? Currently I have behavior tree that when clicked it moves to target and then attacks, but even if someone has attack range, it will move 100cm from the target.. im looking for a way to stop it in inteligent way at the range of target and at the same time don't make it always run to max range when clicked to attack.

[floral compass]

Actually. crazy idea, just rotate the room lmao... duplicate the room out of sight and flip it 90 degrees, then do navigation with a proxy actor on that. Map the proxy actor's position to the original room, just rotated -90 degrees. No performance guarantees 😄

[dense owl]

Not 180?

[floral compass]

For ceiling 180 yup

So duplicate the room 5 times, for each wall and ceiling. I'm sure this has no performance hit at all...

[misty wharf]

You can have a decorator that checks distance to the target and aborts the move to branch of the BT

[uncut rune]

If I want to change the circle radius based on what is unitRange, i have to run task before that query to set that?

I think I found it

will this make the value as UnitRange blackboard key?

[uncut rune]

ok I made it work ! 😄

[signal island]

Guys im making a utility system, do you guys know any reference doc of the system in unreal?

[misty wharf]

You probably should ask the author of the plugin

First time I see that kind of thing

[misty wharf]

AI Controllers don't have a "parent" character... I assume you want the character the controller is possessing, which you can do via GetPawn and then cast it

[static pagoda]

hey does anyone have an idea what i need to do so the character can step up on this Stage? I tried adjusting the Cell Height, Agent Max Step Height and Max Slope and nothing seems to work for me, the collissions for this object are complex so they shouldnt be the problem

[prisma sun]

Hey,
I have a bug when using AIController with FloatingPawnMovement, I don't have this bug when using DetourAICrowdController

When I do a MoveTo, the Pawn is going up and not staying on the floor.
Capsule collision is set to BlockAll, setting it to no Collision does not change anything.
Mesh collision to no Collision

Anyone having an idea on why it could happen or how to fix it ?

[uncut rune]

Check if you have checked ''actor can step on it'', maybe they are stepping on each other?

[prisma sun]

Yes tested but not fixing it :/

[uncut rune]

Why you don't want to use Detour btw?

[prisma sun]

I don't but its the only one not making it bug

[uncut rune]

I think it's because they are all trying to reach the same location and are stepping on top of each other

which may be something with normal AIController just not properly avoiding other units

meanwhile Detour just does everything better if you have ''crowd''

I see you are doing something like rts, then you might want to use Detour AI anyway

[prisma sun]

Yes totally, but the detour is also not working probably like the Avoiding feature is not working 😉

Also every component is having "actor can step on it" to false

[dense owl]

I’ve seen that before, I think it’s because you’re giving them the same destination as was previously said. You can use an EQS context to give them different points around the same point to go to, otherwise if you don’t want to use EQS you can prly do it yourself with a bit of math

If you were using chars I’d say also increase the capsule radius so they can avoid each other better but yeah

[uncut rune]

Also try to use AI Move to and not Move To node, I think it's better for character movements

[prisma sun]

I'm using the node from the behavior tree but I can try a custom one

[uncut rune]

Yeah, I recommend doing custom one, it's much better and you can be more flexible if needed.

Also you can check Acceptance radius to be bigger to like 100 so they will eventually stop before reaching ''exact'' location, but I guess you have it done.

[prisma sun]

Yes tested already and they are going up also

[uneven cloud]

There is no built-in utility system in UE.

[uneven cloud]

Navigation settings only work for asking "can I move here?" In order to actually move there, you need to adjust the character movement component.

[uneven cloud]

How exactly do you think it's better for the character movement component? How the move works is exactly the same.

[uneven cloud]

This is bad advice.

[prisma sun]

So do you have any advice for this bug or hint ?

[uneven cloud]

You're using the floating pawn movement component and trying to get them all to go to the same place. That's not a bug, it's bad logic. If you want them to stick to the ground, you have to actually add that functionality.

[prisma sun]

Nop asking them to move to another actor, and its working totally fine with the AIDetourCrowdController

[uneven cloud]

Of course it is. They aren't trying to go to the exact same spot.

Detour crowd changes the path so that they aren't going to the exact same location.

Having them move to another actor means that they are all trying to go to the same location, that other actor's location.

[prisma sun]

If A move to B and B move to A this is not the same location or I'm missing something

[fleet coral]

Hey, I have pawns that have variable step heights. They can have it increase/decrease dynamically.

I baked my navmesh with the max step height possible in the game, and now my agents don't treat steps that are within that max range, but above their individual current step height, as an obstacle. Leads them to get stuck in those steps, continuing to apply movement as if the path is clear but they can't step over the obstacle.

Any solutions to something like this? I'd ideally want them to treat steps above their current step height as obstacles.

[uneven cloud]

If A moves to B, then it's trying to move to the same location as B. If B moves to A, then it's trying to move to the same location as A.

[uneven cloud]

You can't change the step height dynamically for navigation. You'll either need to use area classes and filters or nav links to change where they can navigate dynamically.

[fleet coral]

So in any project, all agents must share step heights for a given navmesh setup?

[uneven cloud]

No. You can make different agents settings in the project settings.

You shouldn't make a lot of them, because each one creates a new nav mesh.

[fleet coral]

So if I have multiple agents setup, I'll have several navmeshes baked, to fit each agent.

And then if I modify an agent's max step height they'll still be bound to their specific navmesh?

[uneven cloud]

They aren't bound to a nav mesh. Each time they use the navigation system, it gets the correct one based on their agent settings in the movement component.

[fleet coral]

What's it using to get the correct one? Just the best fit based on parameters like radius, height, step height etc?

[uneven cloud]

Definitely radius and height. Maybe the others, but I haven't looked at that code in a while.

[fleet coral]

In theory then, I could setup 2 different agents with 2 step heights, and then if I modify step height dynamically it could select another navmesh to use?

[fleet coral]

I'll test some things, thanks a lot for the help!

[tough ermine]

questions for ai controller and getting an ai enemy, i got a smash bros like fighting platformer, so all the characters are made, my question is how should i get the ai to work, there are no nav mesh bounds as its a sprite based game and is made based of paper 2d is there a way I can write code into the controller to identify which actions the character to take or should i write bp into the character or what

[uneven cloud]

You need to store that animation somewhere and then have a way to get it. There are many ways you can do that.

[uneven cloud]

Do the introduction to AI course that is pinned here. That will go over the AI systems.

[tough ermine]

well thats the problem, i dont use a nav mesh

so im trying to work around that

[harsh storm]

There is more to the AI systems than just the navmesh

[dense owl]

1. IGenericTeamInterface
2. Detection by affiliation
   Tutorial over.

[misty wharf]

You mean this handy dandy page with links to more info also? https://zomgmoz.tv/unreal/AI-Perception/Perception-Detection-by-Affiliation

[copper grotto]

I'm curious how many people use blueprints vs c++ for ai setup? I started with using blueprints for ai as it seemed fairly easy, but I wonder if it quickly becomes a bit overbearing given all the different components of it (i.e. blackboard, behavior tree, ai controller, etc).

[floral compass]

I use both depending on what makes the most sense

Don't think there's a clear cut answer, it always depends on the circumstances and context

Also all those components exist in c++ too

[copper grotto]

Yea that's fair. I'm having a problem with my ai and I'm having a hard time figuring out how to fix it in blueprints. Not sure if it will be easier in c++ or not. I can't seem to get the ai controller to take over the player character when I need it to.

[floral compass]

I doubt doing it in c++ will magically fix it

Have to figure out what's wrong with it

[copper grotto]

Well yea I know that I just am wondering if it might be easier for me to figure it out that way. Debugging in blueprints always feels clunky to me. I can't for the life of me figure out where the problem is. All my googling is showing me what I'm already doing. All of my debugging is showing as all correct up until it's... not. lol. And no idea why.

[floral compass]

My approach would be to first unpossess from the player controller, then possess from the AI controller

You can debug the blueprint function in C++ too

[copper grotto]

You have to unpossess first???

[floral compass]

I'd think so

Since the player pawn is being possessed by the player controller

[copper grotto]

Well shit, that might be the problem. I thought when you called Possess it would just put whatever you're trying to make possess it in control. I'll try that. Would be fantastic if it's that simple, if not a little frustrating that I've been pulling my hair out on this issue. lol.

[floral compass]

Never make assumptions, need to be pragmatic about it.

Never is a strong word, but you get what I mean 😄

[copper grotto]

lol yea. Well, that didn't seem to work right off the bat, but it gives me some ideas of new things to try at least.

[floral compass]

Also I don't think AI controller starts its logic automatically on possess, you might have to manually start it.
But that would be the next step after successfully possessing

[copper grotto]

Yea I've got that stuff in there to run the behavior tree. but for whatever reason the unpossess and possess doesn't seem to be working. I put print strings after each execution node here and each time it's still displaying the BP_ThirdPersonController. I've gotta be doing something wrong but I don't know what?

[floral compass]

First off I'd get the controller from the player character instead of calling "GetPlayerController"

That would at least assure that you're trying to unpossess the correct controller

Next you can check if your player character is actually being unpossessed by debugging their "Unpossessed" event

Also your "Third Person Character Ref" variable doesn't seem to actually have any value. At least not from the screenshot alone.

Since you're doing a "Get Actor of class" I assume you'd have to set that into the var first

[copper grotto]

Ah ok now we're getting somewhere. Ok so let me ask you if you don't mind, why did the GetPlayerController not work? My understanding was that Player Index 0 should always be the player if it's a single player game. To my knowledge, I don't have any other player controllers in the game (if I do maybe that's a problem to investigate) so why wouldn't that work the same as getting the controller from the player character?

[copper grotto]

That's the BP_PlayerCharacterAIController and that's the one getting passed into the Possess node.

[floral compass]

No idea, just a shot in the dark

[floral compass]

But you're passing it into InPawn. Why would you pass a controller into a pawn variable? Does that even work?

[copper grotto]

no, i'm passing the BP_ThirdPersonCharacter into the InPawn.

[floral compass]

Controller should go into the Target pin

Oh ok!

That's your player pawn, right?

[copper grotto]

Correct

[floral compass]

Then why do GetActorOfClass if you already have it?

[copper grotto]

The GetActorOfClass is getting the ai controller, not the player character.

[floral compass]

Ooh, gotcha. It only says "Player Chara-" so I thought it's the player pawn

[copper grotto]

And maybe that's the problem? maybe i'm getting the ai controller in a way that's incorrect? I see one in the outliner though and i assume that's the one I want to get, right?

[floral compass]

I mean

Is the AI controller spawned in the level?

If you haven't spawned it then you can't get it

[copper grotto]

Yea it is there, I've looked to verify that it's there (in the outliner) and I've also debugged the return from that isValid to ensure that whats getting returned from there is the ai controller.

[floral compass]

And that AI controller is not possessing anything else right?

[copper grotto]

uuum it shouldn't be. is there a way to debug that?

[floral compass]

I guess gameplay debugger? Backtick is the hotkey for it I think

[copper grotto]

So I've never used this gameplay debugger before, but if i'm understanding this correctly, it looks like the ai controller is possessing the player character? So I'm not sure why it doesn't read with that when I print out the controller.

[floral compass]

Looks like it to me!

Again, you'll have better info if you debug your character's "Possessed" event

[copper grotto]

Yea that appears to show the ai controller. so, that's working but I'm still getting "none" when trying to get my blackboard.

[floral compass]

How and when are you getting the blackboard?

[copper grotto]

In the BP_ThirdPersonCharacter, I have a custom event that gets triggered after the controller is switched. On that event, I have a GetBlackboard node that takes a Target which I've tried several different ways of passing in the target. I've tried GetController, GetPlayerController, GetAIController. None of them seems to work.

[floral compass]

Have you tried this event in your character BP?

And then getting the blackboard from that controller?

[copper grotto]

No, but I suppose that makes more sense than how I'm doing it now. I'll try that. I gotta run real quick but will be back to this in a bit. Thanks a ton for your help!

[wraith charm]

Does anyone have any cool resources for how to think about NavMesh when working in large open-worlds? Both regarding dynamic generation (such as with the NavMesh invokers) but also NavLinkers, and just general landscape construction to make the process less painful?

[misty wharf]

The builtin systems for this are unfortunately not implementable in bp. You would need to make some custom system which for example casts the detected actor and looks at a variable on it to determine whether it's friendly or not

It depends on what the problem is really

When it sees an enemy you probably would want to assign it to a variable and have it keep chasing that one instead of choosing a new one to chase when it perceives another

[lyric flint]

I can't get AIPerception hearing to work

Hearing config is added to the senses

with a 3000 range

The pawn that makes the noise has both "AIPerceptionStimuliSource", and "PawnNoiseEmitter" components.

What am I missing?

[floral compass]

Probably want to check "Detection By Affiliation" in your sense config

[lyric flint]

All are set to true

Doesn't work.

OnTargetPerceptionUpdated I hooked up a simple print string, to check if hearing triggers at all. It doesn't. So it's not like a complex system where somewhere along the way something goes wrong.

The most primitive possible setup.

Sight triggers, hearing doesn't

The N definitely works, checked with print string.

But hearing doesn't trigger.

Also tried the same nodes hooked up to an event on character jumping, because I thought that N input making the noise might be the issue. The event works, the hearing still doesn't.

[distant pollen]

Can someone explain to me the Difference between these two nodes?

Just one is a Function and one is a Variable?

[obtuse igloo]

Anyone know how to or have resourceful links on creating a Utility AI behavior tree? For example having the selector nodes switch task actions based on the Utility Score of the AI?

[misty wharf]

If you want it to stop when sight is lost, check the successfully sensed value on the stimulus. This will be false when sight is lost to something, so you can use this to remove the active target or choose a new target from the other perceived enemies (you can use get perceived actors to get a list)

[misty wharf]

The only one I've seen is this, which adds a new type of composite into the BT to allow doing utility value selections https://github.com/kamrann/BTUtilityPlugin

[misty wharf]

It's possible there's no difference beyond function vs variable. You would need to look at the C++ code for the function to find out if it does something else

[obtuse igloo]

I'll try this out! Thank you! 😊

[light void]

Here for advice on what would be the clean way to do it: I hae a building with multiple rooms and I need NPC to wander from room to room. Most rooms will have a default "wandering" inside but for some I'd like something more specialized.
Would it be better to swap their behavior tree when they enter a room? Have one BT for wandering outside, one for wandering in room and one for acting in rooms?
Or is there something more appropriate to do?

[misty wharf]

Seems entirely up to you. You could for example use smart objects in the room and have it use a behavior tree on the SO or something, or use gameplay behaviors instead of BTs, or not even use smart objects

[uneven cloud]

There's a significant amount of functionality that is not exposed to BP, so only using it can cause a lot of problems. Plus you have all the normal issues with BP.

[uneven cloud]

Then why are you unpossessing the AI controller? You need to unpossess the player controller from the player character first.

[copper grotto]

That's exactly what I'm doing.

That AI controller wire does not go into the unpossess node if that's what you're thinking. I just hadn't taken the time yet to clean up the wires, so it's straight across, I noticed after the screen shot that it might look confusing.

[uneven cloud]

There's an article in Game AI Pro for a BT/Utility hybrid that works the way you are looking for.

[uneven cloud]

No you are not according to the image you posted.

[floral compass]

Some redirectors would help :p

[uneven cloud]

Ugh. I hate BP.

[copper grotto]

agreed. I just hadn't noticed before posting the picture.

I tend to use both bp and c++, but ai is fairly new to me so I'm trying to get used to a bit. I'm sure at some point I'll move to c++, but it's a lot to take in all at once.

[uneven cloud]

Run behavior tree should also not happen outside of the AI controller. It should be done in the AI controller's possess function.

[copper grotto]

That is the ai controller.

[uneven cloud]

Why are you doing any AI work on the character? That should be done in the AI controller. Likely what is happening is that you are running the BT after the possess function while you are trying to access it when it's being possessed.

[uneven cloud]

You are unpossessing the player controller in the AI controller?! That should be done in the player character.

[simple wagon]

Heya folks, I feel like a dummy but I'm trying to follow: https://dev.epicgames.com/documentation/en-us/unreal-engine/behavior-tree-in-unreal-engine---quick-start-guide .

I finished it, and ... nothing really works aha! Watching my BT, it tries to find a random position, triggers a moveto, but the value stored for PatrolLocation is null everytime. Breakpointing to look at the value being assigned, screenshot shows that the Key struct seems to be trying to assign EnemyActor key type, not PatrolLocation key type.

In the tutorial it simply says "Promote the key off of Set Blackboard Value as Vector, and rename it". That doesn't appear to be enough to actually have this BTT tell the BB what key to assign? I simply named a variable, and I don't see a way to tell it what key type to choose unless I go through constructing a Key struct fully. Is the tutorial simply wrong here or have I overlooked something?

Thanks rubber duckies haha. If I instead do this and construct my own key struct then it works as intended.
I'll read through again but it sure seems like the tutorial is missing this?

[misty wharf]

The tutorial is correct but it's missing a step where it says you need to make the patrol location instance editable and then assign the BB key to it from the BT editing view similar to the other variables you can edit there

[simple wagon]

Oh I see! And it kind of autograbbed it, interesting. That was definitely the intention they had

Thank you

[misty wharf]

I don't think it'll autograb anything so if it got some value to it by default it was a coincidence lol

[simple wagon]

I think that because you name it identical to the key in the BT it's picking it up once it's instance editable. When I tabbed over it changed the BTT_RandomPatrol node value "PatrolLocation: None" to "PatrolLocation:PatrolLocation".

[misty wharf]

Oh really, it didn't use to do that at least I'm fairly sure

[uneven cloud]

You need to set the default value to the BB key name. While promoting it to a BB key selector works, it's completely unnecessary. BB key selectors should be used as variables to set the key in the BT, which is a better option than hard coding the key name.

[simple wagon]

I agree yeah. Seems odd they chose to do that in the tutorial, it was a really confusing part for me

[uneven cloud]

Then it sounds like you have a nav mesh problem.

[uneven cloud]

It's a quick start guide, not a best practices guide.

[simple wagon]

True

although it does continuously say best practices through it which gives the impression that it is trying to be : P

[foggy moth]

I have a GameplayAbility that i'm using to drive a MoveTo task - and at any given point I need to PAUSE this movement... for certain cinematic effects, which afterwards I'll be resuming movement on the cinematic completed.

I cannot use CMC->StopMovementImmediately() - because this will trigger this MoveTO() task OnMoveFinished() branch :/

Any other solutions out there? I've been searching at all forms of AIController, CharacterMovementComponent, even pausing/cancelling the GA ... but none of these methods are working :/

[dense owl]

What’s wrong with the move finished triggering ?

If bCinematicInterruption -> MoveTo previous goal

[foggy moth]

because in all honesty i want to cancel this ability - but i'm having the HARDEST time of doing this....

Its a turn based strategy game.

Logic:
1: MoveTo (as seen above)
2: Overlap enemy sphere (detection)
3: Play cutscene on overlap, pausing movement (desired) OR cancelling ability as i'm caching the destination that hte player SHOULD go to...
4: OnCutsceneFinished - resume movement OR do a new MoveTo ability with the destination from teh cached location.

[dense owl]

I would ask #gameplay-ability-system if you need to cancel a GAS ability

The movement part can be easily resumed with another move order

[foggy moth]

been there - tried it. i'll work with Khaos - because hes got a doc that says how to do this.. simply put my UGameplayABility* is NOT VALID (CDO) - which shouldnt be the case.

[dense owl]

There’s also time dilation or pause game

[foggy moth]

pause game - wont allow for cutscene to play no?

i should say ...

this is NOT a rendered cutscne

rather...

[dense owl]

I honestly don’t know. I know some things can be set to run while paused but idk about cinematics

[foggy moth]

camera switch to the enemy overlapped camera and play a AnimMontage + audio clip

so.... i dont think PauseGame will be a solution

[dense owl]

Fair enough

[uneven cloud]

Why are you trying to do AI logic via GAS?

[foggy moth]

AI use gameplay abilities - yes?

[uneven cloud]

That's not what I meant. It looks like you are trying to do the actual decision making in an ability.

The answer to your question is to lock the path following component while the cutscene is playing.

[misty wharf]

It works just fine. If it returns an empty array then the NPC isn't currently perceiving any other actors

[stiff gale]

Is there any new feature in UE5.4 that will reduce the cost of 100s of regular AI?

[misty wharf]

I don't think there's a magic bullet that will optimize your game for you

In order to determine how to reduce their cost you would first need to find out what part of the AI has the performance cost

just saying "AI" means very little in terms of what it could be (could be CMC, could be skeletal animations, could be perception, etc. etc.)

[desert parcel]

Hello guys im seeking help and advices from you. If anyone can give me a hand, tip , advice , information or anything please do .
I need to finish working on this project and i still dont know how.
I need to make an AI that learns from the player gameplay and then plays just like the player and i dont know how or where to start (im using ue5).
I have reduced my task it to just a bossfight to minimze the complexity of the project

[floral compass]

There's the "learning agents" plugin but it's relatively new. No idea how stable it is.

[uneven cloud]

Is the actor affecting the nav mesh? You can use the visual logger to see if it's failing to project the goal location.

[desert parcel]

Yeah i have read some about it and i dont think it can help me achieve exactly what im trying to do here.

[uneven cloud]

That's a very large topic with no easy solution. Like PhD level research.

[desert parcel]

exactly what im doing 😭
im doing this for my engineering final study project

[uneven cloud]

I honestly wouldn't recommend it if you are looking to get into the industry. We don't use it for agent behavior, because it doesn't make fun player experiences.

There are 2 good GDC talks about it. One from killer instinct and another from Warframe.

[desert parcel]

is this for me ?

[uneven cloud]

Your AI can't navigate to something not on the navmesh.

[uneven cloud]

Yes.

[desert parcel]

well its not about "FUN" player experiences. Its more about how far or if it is duable at all

[obtuse dome]

Is there a way to make Nav Link Proxies treated as 0 distance? I have a teleport door that NPCs can use, but having issues where if the distance between the NavLinkProxy start & end + distance from NPC to start is >the distance from the NPC to the end, it will walk the long way around rather than taking the instant teleport door

[uneven cloud]

The 2 talks I recommended are from games that shipped using it. There are more talks that are theoretical, but those are the only practical ones that I know of.

Making games is about creating fun player experiences. When I'm hiring, I prefer resumes that have projects that understand this.

That has absolutely nothing to do with it.

[desert parcel]

Dont get me wrong i totally agree with you. Afterall we are doing this for ... FUN. 🙌

[uneven cloud]

You affect the weight of pathfinding by using area classes.

[uncut rune]

What would be the best way to toogle ai senses on character? Like Imagine I can click A and S, and they will turn on and turn off, so:
if Ai can sense again, will get targets around it and attack
if Ai cannot sense, will lose targets and stop everything
and then again

Does AI Perception works on tick?

1. Could I use boolean after AI to tell it if it senses or not?
2. I also tried with this enabled node

So far I'm able to ''stop'' character, but I'm not able to enable it again so it will start looking around again (like if he is in range, he should get them imidiatelly).
I will keep trying but if anyone has hints what to use for this I would appreciate it.

Currently I'm testing so this is how it looks

keep in mind I'm changing it all the time as I work on it right now but if anyone can give me hints I will be thankfull

[misty wharf]

I would try to toggle the sense off and see if it causes on actor perception updated to trigger

If it does, then you could use that to update your logic (eg. when sense is disabled, it would probably lose sight and successfully sensed would be false)

But if toggling the sense doesn't trigger on actor perception updated, then I would just sort of fake it. Basically whenever you toggle it off, you would remove the current target it has or whatever and stop reacting to sense events. When you toggle it back on, you would check get perceived actors to see if you should update the target immediately, and again react to perception events as normal

Also I see you are using on percetion updated - I would generally suggest using on actor perception updated as it will trigger once per type of stimulus received for an actor, which is usually a lot easier to work with than the array

[elder jay]

isnt this updates only on "trigger"?
once your target is seen will remain seen until its not seen again?

[misty wharf]

Yeah this triggers once per sight / loss of sight. While something is actively being perceived, it does not trigger again for that particular actor until sight is lost

[elder jay]

https://docs.unrealengine.com/4.27/en-US/BlueprintAPI/EventDispatchers/OnTargetPerceptionUpdated/

[misty wharf]

On Target Perception Updated is called when something becomes visible, or when it is no longer visible

And only on those occasions

If you need to do some logic while something is visible, then you would need to use Tick or a timer

(If you need to run it repeatedly like that)

[uncut rune]

Do you mean On Target Perception Updated? I don't have actor. And yeah toogling it, doesn't print anything from the on Perception Updated.

[harsh storm]

Yes, The Target Perception Updated one

It's far more reliable than On Perception Updated

(At least in my experience)

[floral compass]

Also contains more info, no idea what you would even use "OnPerceptionUpdated" for aside from very simple logic? Also having to wrangle that array of actors seems like a pain

[uncut rune]

I think i miclicked it when I started building logic 😄

i will try some things

[misty wharf]

Yep target perception is what I meant :)

[stone walrus]

guys anyone can share me their door bp for ai that open door when player is seen and when not seen it moves to its location as usual

and i am not using behaviour tree

[floral compass]

I doubt anyone will have that for ya

[stone walrus]

can u give me good video for that i am making game like granny

so

specfically

door are main issue i am facing

[elder jay]

🙂 than there will be way more to come.

[lament mortar]

Problem: AI not moving in package/build game

The AI works fine in editor but when I pacakge the game, it does not move from its current location.
Does anyone know why that might be the case?
I am assuming this is to do with nav mash not being build? not sure.

[stone walrus]

nah i have all the game i made

all way till

end i have most of the trash

doors are the main issue

[misty wharf]

The solution depends on how you want it to work

The simplest solution is to have the door open automatically based on an overlap

[uncut rune]

I came up with something and just want to ''write it out loud'', so you can analize with me if you want. For now, I think toogling sense isn't the best, because it seems a little bit complicated, because for example, let's say I have 5 enemies around me, I sense them all, and they are probably put in the array in some kind of order. Now, let's say I switch my character to ''fake not sense anything'', let's say in these 10seconds, enemies regrouped and the one with index 0, that was the target, is the most far away. If I turn back sense on, it should ''recalculate'' and find the closest target, at least this would make it more organic, than if it sudenly went for that guy in the back. Possible fix? When sense back on, check array, get distance to every target and choose the lowest one + check first if the old target is still in the sense area?

2nd solution I'm thinking is to have states of my unit like:
Stop , Hold, Attack and these would be linked to the behavior that it should be doing while in that state. So like in Stop, I would have only Wait 5s looped.
In the Hold, I would have task that checks if are there any sensed enemies? Wait 0.5s and check again and loop, if enemy is found, it would go and attack, with addition, that when first enemy was sensed, i save current position, and if the distance from ''starting position'' is let's say over 2000, then it should not chase anymore or just simply, lose target? what would happen if the target came back, it should find it again, gets complicated a bit
and while in Attack, it would just have sequence that if any target is in the sense area, go attack it and chase it to death, and if dead, check targets around and just continue find targets and kill them (in the sense range?).

Any flaws?

[floral compass]

Probably some, but I can't get what you're saying easily into my head xD

[uncut rune]

more or less, i'm prototyping and i will watch some video to check if it makes any sense xD

just making notes

[misty wharf]

I would suggest just trying to implement it and seeing how it behaves

Sometimes the behavior is better to actually see in action at least when it comes to gauging whether it behaves in the way that works well in the game

[uncut rune]

I will try 😄

[quaint wedge]

Hey, I can see that 5.4 includes updates for the NavMesh generation.
Does anyone know if it includes some changes related to NavMesh streaming ?
Or on-demand tiles generation ?
(As far as our problems go in 5.2, we're using world composition, Level streaming, with ModifiersOnly NavMesh generation which randomly doesn't generate the NavMesh properly in streamed sub levels)

We chose not to use Dynamic generation for performance reasons.
Requesting periodic NavMesh updates would be a way to go, but we never managed to make it work.

[uncut rune]

oh god, my engine bugged and wasn't printing anything and I was looking for mistake in code while everything was fine.. just needed to reset it ugh xD

[uncut rune]

What would I have to put or change to make AttackTarget be set to none, when it leaves the IsInChasingRange? Or maybe I should put AttackTarget not set on the WaitForTarget, and execute node IsInChasingRange to clear AttackTarget when it's true or false. I will try. xd

[simple wagon]

Cross posting in case someone here has run into this #animation message

Basically my animation blueprints are not firing properly when the controllers are controlled by an AI Behavior Tree. The ABP never seems to understand that the controller is moving or rotating, it never fires its sequences to even check anything. It's like the ABP doesn't exist, although Idle is firing the whole time.

[simple wagon]

(figured out some of it, by default it seems the CMC will not get acceleration data from the MoveTo function used here, have to enable Use Acceleration for Paths. This does not fix the rotation issue though)

[uneven cloud]

Did you just remove the collision? If so, that's a hack and not a solution.

[simple wagon]

Solved mine, #animation message for posterity in case someone searches for it in the future haha.

[uneven cloud]

Forcing a BT into acting like a state machine is never a good idea. Also your first one is completely overthinking the problem. Just use the EQS to find targets. There's a built-in generator to get them.

[uneven cloud]

This is incorrect. The path following component doesn't do anything with acceleration. The CMC doesn't use acceleration unless it's turned on.

[simple wagon]

I'm not sure how it works under the hood, but, I do know that if it's disabled, Get Current Acceleration from the movement component will return a null value to the ABP, resulting in all animations that rely on that changing to never fire

The CMC won't have a valid acceleration unless the value "Use Acceleration for Paths" is checked?

[misty wharf]

Correct

[uneven cloud]

Because the CMC doesn't use acceleration for paths unless it's checked.

Which is completely different than what you said. That it doesn't get the acceleration. You might think it's not an important distinction, but it is.

[simple wagon]

Thanks for helping me understand, I think I don't understand enough of the underlying systems. So "use acceleration" to me sounds like I have a variable called acceleration, and I am going to use it, for a path system.
But I actually don't have a variable at all until I check that box

it's null

I'm sure a large part of this is "For paths" I don't fully get the implications of. I assume paths along a navmesh

[uneven cloud]

There are 2 solutions to that problem. 1. Turn on use acceleration for paths or 2. Use velocity in the anim bp. The first one does change how things work, which might not be ideal for every project.

[simple wagon]

I've solved the problem

I'm just trying to understand why that button solves it

[uneven cloud]

The CMC doesn't use acceleration for following a path without it turned on. I'm not sure how to make you understand that.

Do you understand what acceleration is?

[simple wagon]

I think you're not understanding my question, so, that's okay I'm gonna move on. Thank you though

[uncut rune]

Oh wow, thanks for the tip with the finding actors. I will change to that definitely. For the other aspect, well I don't have any other idea how to make it so it will behave the way I want. And FOR NOW, it works as I have Attack and Hold ''states''. I will see what problems will be in the future, but so far, it's ''ok''.

If you want to tell me alternative I will be happy to take feedback, but any examples?

so far I made Hold like this and attack, which can be switched with A and S key

[uncut rune]

I just called it States but it's more like Commands, I don't understand what is the real problem I should study

[uneven cloud]

See the pinned messages

[uncut rune]

I watched them all. Still don't see problem with what I'm doing.

[uneven cloud]

It's not a video

[uncut rune]

I don't believe this works in my case because I need to connect commands with behaviors. It's not computer ai thing that will get blocked, but units should do what players tell them, and nothing else.

[floral compass]

I wonder since so many people post pseudo-state-machine behavior trees here:
What would be an appropriate, beginner-friendly model to handle a set of complex behaviors with behavior trees (since they already exist in UE) that does not result in a huge mega-tree?

I mean

Surely you would have to at least split your BT up into multiple smaller trees, right?

[uneven cloud]

What people don't seem to understand is that forcing it into a FSM actually causes the huge mega trees

[uncut rune]

So what instead? Make custom events and put logic in there because of that? or what

[floral compass]

Well true. But that's something you only know if you know.

Wonder if there's something inherent to BTs that makes people go "oh yeah let's put some states in here"

[uncut rune]

like you are saying it's bad, but you won't tell example (even simple) how to do it other way

[floral compass]

Aside from bad youtube tutorials lol

[uneven cloud]

It's not inherent to BTs. It's the tutorials.

The main problem is that people have a hard time understanding the flow of a BT. Another problem is that they tend to completely over think it, instead of starting with the simplest version.

Yet another problem is that there isn't one way to do anything, but that's what everyone is looking for.

[floral compass]

Especially so with AI it seems!
How could you then reinforce the fact that priority is key instead of arbitrary transitions across the whole tree?

The latter being what I assume to be the motivation behind shoehorning states in

[uneven cloud]

People want arbitrary transitions across the whole tree.

Which is fine, make a FSM. It shouldn't take more than a day.

[floral compass]

In other words: At some point the way a BT flows might not be the right tool and you need to switch tools, right?

[uneven cloud]

Yes

[floral compass]

Well there you have it @uncut rune 😄

Thanks for the insights

[uncut rune]

Switch tools, means to do Events in blueprints instead of behavior trees?

[uneven cloud]

You can also use the state tree if you want

[uncut rune]

Ok I will check out state trees

[grim tartan]

Is there any way to learn why a Move To Location or Actor, or AI Move To might be failing/ aborting?
Some like in-depth logging?

Currently fighting an issues.
Nav mesh exists, I can move to other nearby points, but not that specific point

[uneven cloud]

I use a utility/ BT hybrid, because I need some things that the BT doesn't work for.

[harsh storm]

Just because UE offers it, doesn't mean you have to use it

Realistically, if you only have a handful of states - FSM's are more than adequate

[uneven cloud]

The visual logger

[grim tartan]

I'm not familar with that?
Context?

[harsh storm]

It's the tool to debug why the movement failed

[floral compass]

True, but at least BTs are more stable that StateTrees right now at least

[harsh storm]

I didn't say to use StateTrees

[uneven cloud]

https://youtu.be/FiJTBUNJMQk?si=4kSWTx0CYe0g-P77

[harsh storm]

I have my FSM right smack dab in one of my units. I don't do anything fancy. Because I don't need anything fancy.

[obtuse igloo]

Hey all! I've been trying to install this plugin but it's not working (probably not compatible with 5.3?) https://github.com/kamrann/BTUtilityPlugin?tab=readme-ov-file#readme

Are there any other sources or ways I can set up my behavior tree to simulate Utility AI? For example the selector would calculate utlity with each selection then execute based on the score of an action?

[grim tartan]

How does that tell me the abort/ fail reason though?
That involves me logging in my own logic, which doesn't provide a good fail reason.

[uneven cloud]

Can you reach out to the creator of the plugin

[uneven cloud]

The navigation failures are already logged. Along with all the other AI systems

[harsh storm]

It logs the move stuff already. So you just look at the log.

[obtuse igloo]

Unfortunately not, even the inprogress mod they were working on does not exist anymore

I'll have to do a work around for the way i wanna do the AI then 🤔

[uneven cloud]

What are you trying to score?

[grim tartan]

Weird.
Says it fails to project to a nav mesh, but I'm staring at the nav mesh all around.

[obtuse igloo]

Currently I have these actions for my AI; Roam, Eat, Sleep, Play (virtual pet AI in progress lol)

I have it set up in blueprints where it works and selects actions based on calculating a score, but would like to put the core logic into behavior trees (selecting what task to perform)

[uneven cloud]

My utility/BT hybrid works differently than that plug-in. The utility selection happens outside the tree and each one has it's own BT.

[obtuse igloo]

Ohhh like a function that the BT executes in the controller? does it use an enum to switch the current action?

[uneven cloud]

No. The main BT only has the run behavior dynamic node. Then the utility action sets the tree to use.

[obtuse igloo]

Ohhh that's an interesting way to do it actually

so you just create multiple BTs for each action?

i think ill try that out 👀

[uneven cloud]

BTs aren't really made to jump around.

Each action only has 1 BT unless a different character needs different behavior.

[grim tartan]

Hmmm.
I found the issue, but I'm usure how to handle it.
I move to an actor, but I also have a collision on that other actor to block the nav mesh, so that AI know to path find around it.
But, since it tries to move to an actor location that isn't on the navmesh, it fails.

[uneven cloud]

Does that actor move? Because doing that on a moving actor is really expensive. There are better ways to do dynamic obstacle avoidance.

[grim tartan]

It does not move.
Its just static

[uneven cloud]

You either need to not block the navmesh or find a location on the nav mesh that is close to the actor. For the 2nd one, I recommend using the EQS.

Or you can calculate it yourself using math and project location to navigation function.

[grim tartan]

I thought this would've helped for the 2nd possibility.

I may need to use EQS then, never touched it.
Brand new to AI in general

[uneven cloud]

Random is not a good way to do it. You'll get points on the other side of the actor, which makes the AI look dumb.

[grim tartan]

Its better then my AI actually being dumb right now. 😛
But, also didn't work

[uneven cloud]

It doesn't work because the origin is not on the nav mesh

The EQS generates a bunch of points around a location, can filter out any not on the nav mesh (projection) and run tests to find the best one.

[grim tartan]

I assume EQS is performant?
It does say its experimental, and not to use. 😛

[uneven cloud]

It's been experimental since at least 2016.

Yes, the EQS is performant. It's time sliced so it only does so much work each frame.

[grim tartan]

Guess its time to learn EQS, and AI stuff. 😛

[uneven cloud]

The intro to AI course that is pinned here is a great place to start.

[floral compass]

Is that better than switching the entire tree at runtime?

I do something similar but so far always switched out the whole tree

[grim tartan]

Cool.
I shall check it out. 🙂

[uneven cloud]

It's more performant and causes less bugs. If your way is working it shouldn't be a big problem.

[floral compass]

I'll know what to look out for in case of bugs tho!

[uneven cloud]

I shipped one game doing a full switch out. It was fine, but I found that the dynamic subtree just worked better.

[floral compass]

Can you inject trees into subtrees?

[uneven cloud]

Oh! The biggest reason is because you have to set all BB keys.

[floral compass]

Ah, true I do that every time

[uneven cloud]

What do you mean?

[floral compass]

Like using a "RunBehaviorDynamic" within a tree that itself is a subtree if the main tree

Nesting subtrees at depth >2 I guess

[uneven cloud]

Yes you can. Not sure how deep you can go.

[floral compass]

Okay good to know 👍

[obtuse igloo]

So to make sure i'm not too tired, You're using one BT for the core of the AI, then run other BTs for the actions it selects in the core BT in one AI Actor?

[uneven cloud]

No. I'm using one BT that only runs a subtree. That subtree is selected based on the utility selection that happens outside of the BT.

[obtuse igloo]

OOHH SUB TREES of course dfkfdjgkfj

gotcha, i'll keep that noted then! Thank you lots

[uneven cloud]

Run behavior dynamic is a node that runs a subtree that is set dynamically at runtime

[undone heron]

For some reason the AI are moving to completely different locations than the given transform. If I draw a debug sphere on the transform it shows the exact place I want them to go, yet they don't. It doesn't fail either, it goes to the On Success with a movement result "Success"

Any ideas why?

[misty wharf]

Hard to say, I would try using the visual logger to see what's going on with the path and navigation

It's possible that your goal location is not directly navigable and it ends up projecting the point into a weird location for some reason... can't really think of much else

[undone heron]

how do i enable the visual logger?

[misty wharf]

It's under Tools->Debug

Press the start button on the vlog window, then run PIE and it should show stuff for you

[undone heron]

Thanks 🙏

[uncut rune]

Evaluators in ST are kinda like services or eqs in bt?

[coral mesa]

i could be dumb but whats the basic needed for StateTree to work?

like where to add components exactly?

[floral compass]

There's a StateTreeComponent which you would add to your AIController if your intention is to use it for AI. Then you configure the StateTree asset on that component. Just make sure that the asset has "StateTreeComponent" schema selected.

Also make sure you have no other BrainComponent on your AI Controller, otherwise you'll have to resolve it yourself

[open swift]

When you guys have a melee enemy pursuing the player, and are using EQS to determine where to stand, how often do you re-run the query? Every frame? On an interval? Only when the previous position is no longer valid (the player moved a certain distance)?

[misty wharf]

Every frame is probably not a good choice because the query might not resolve in a single frame always

But in general it sounds like this depends entirely on how you need it to function. For example what is the point of querying for a new position often if you're not going to move into it?

[uncut rune]

Why there is so little about state trees on youtube 😦

just 1 example from epic's officials that is repeated across 4 tutorials xD

[misty wharf]

Too new system and it's complicated to understand unless you dig through the code which the average UE youtuber doesn't seem to do much

I wrote a few odds and ends on it here https://zomgmoz.tv/unreal/State-Tree/

[uncut rune]

Is that thing with the Succesfull enum node still bugged where you have to go around ?

[misty wharf]

Huh?

[uncut rune]

That you have to manually tell the task to finish because it will get bugged

so you create fake Succesful thing

[misty wharf]

I have no idea what you are talking about lol

[rustic pond]

hello, I have pathfinding problem that causes AI controlled pawns to get stuck almost always in this particular layout
so basically pawn #2 tries to reach its destination but is blocked by prop on the one side, and pawn #1 on the other side
RVO is enabled on both with 140cm radius, navmesh settings are pure default
can something be done about this?

[narrow mason]

I just implemented it in my project. Not using the Gameplay State tree plugin.

I read the source for Mass StateTree, Gameplay StateTree, and the StateTree plugin

It may just be my first unreal engine blog post 😂. It's a bit complicated to get into, but quite easy once you understand it

[uncut rune]

Is it possible and easy to do to switch these states with keys on keyboards?

[floral compass]

I'd use state tree events for that

[uncut rune]

Tree events? 😮

this is something inside State Trees?

how do I contact from playercontroller to there

[floral compass]

    UFUNCTION(BlueprintCallable, Category = "Gameplay|StateTree")
    void SendStateTreeEvent(const FStateTreeEvent& Event);

This function

[narrow mason]

What melon said

[uncut rune]

wait I have to use C++ for state trees, fuck me

[floral compass]

Nope

BlueprintCallable

It triggers event transitions such as this

[uncut rune]

do you mean there is node for this?

tat I can use in playercontroller

[floral compass]

BlueprintCallable means there is a node yes

[uncut rune]

ohh xD

[floral compass]

Even if you don't know C++ it's always useful to have a look at a component's header file just to see what else it can do

[uncut rune]

How do you structure folders in project for that? Like AI > StateTrees/BehaviorTrees ?

[floral compass]

However you prefer

Has no bearing on how things function

[misty wharf]

There's two schools of thought for it in general

1. Organize by type
2. Organize by relationship

by type just means you'd have something like AI / BehaviorTrees and all your BTs go there

[uncut rune]

For now I had like AI > BehaviorTrees, Tasks, Decorators, EQS

[misty wharf]

by relationship means you'd have something like NPCs / NPCGuy which would contain all kinds of assets related to this particular npc

[uncut rune]

not sure where to put StateTrees 😄

well its the least problem, ill figure it out

btw can I fully translate something like this to StateTree and not have anything in behavior tree or I will have to divide this a bit?

[floral compass]

No problem

[uncut rune]

so I fully can use StateTree and forget about behavior trees?

[floral compass]

Depends. Pick the right tool for the job

Some people use both

Some neither

BTs are more flexible at the moment. But if you don't need such flexibility it's not going to influence your choice

Also StateTrees are quite buggy when you dig deep into property bindings, but otherwise work

[misty wharf]

I would advise trying to build something in STs first before committing to moving anything to it

[uncut rune]

doesnt sounds inviting xD

[floral compass]

For simple things it's really no problem!

[misty wharf]

As far as I know there's only one kinda annoying bug with the prop bindings

[floral compass]

Also supposedly will be fixed by 5.5

[misty wharf]

But it has a ~reasonably easy workaround

[narrow mason]

What's the bug, cause I just threw all my eggs in for my RTS game

[misty wharf]

It won't let you access nested properties unless it's the context object

Eg. SomeActor.SomeProp won't work

The workaround is to make a task which takes SomeActor and pulls SomeProp from it, then you can bind to the task's output

[uncut rune]

I'm trying to make first thing in state trees for testing and learning, since I don't need the actor to be character or even have aicontroller, i could maybe use StateTree for something like Tower?

[misty wharf]

Yes, I think even UE's own docs show state tree used for some moving target thing

[uncut rune]

i feel like soon I will transition all my blueprints into state trees and the game will be only statetrees lol

[narrow mason]

Oh I see. I should be fine then. I'm not really using objects besides a subsystem

[floral compass]

There's also a 100% crash in case you're using BP structs
And binding in container elements is problematic (e.g. binding to the first element of an array)
And some linked subtree bindings are wonky

I imagine the new linked subtree asset feature won't be spared from a few bugs with binding, too

[narrow mason]

Oohh. This is quite a number of bugs. For BP structs, I think you have to create a custom schema that accepts UUserDefinedStruct

I'll tread carefully and limit my use of bound data for now

[misty wharf]

BP structs should generally be avoided anyway

[harsh storm]

I just avoid the plugin altogether. Wasn't a fan of having to recreate my ST when it would bug out.

Not too terribly difficult to write a FSM either

[narrow mason]

Now that I think of it, it did bug out on me once. I had to delete some states. Something with serializing a previous version of the tree and running that instead

[uncut rune]

ohh, wait do I create individual statetree of every state?

[narrow mason]

Nope

[uncut rune]

I thought I would put like Attack, Stop, Hold, in 1 state, but it turns out it's all alone?

[narrow mason]

These sound like states that you'd have in a single state tree. Each state then has a bunch of tasks.

You don't necessarily create a new state tree for Attack, Stop, Hold

[uncut rune]

oh ok

[floral compass]

This was the worst.
Luckily it seems to be fixed

And I'm too dumb and lazy to implement anything that approximates the comfort of property binding in a custom FSM

[narrow mason]

Yeah, the custom UI is quite convenient. Although I think there's a lot of indirection with objects. The entire setup could be made a lot more simpler

Too many proxy types and containers within containers

[floral compass]

And also you just can't bind UFUNCTIONS like you can with property access nodes in the Anim BP
Which really sucks because now all the variables that your ST needs have to be cached somewhere instead of just being able to call a function to get them..

[calm knot]

is there a way to bake recast in midair?

[uncut rune]

About the bug I was talking before, Is it still bugged that these nodes doesn't trigger Succesfull in the tasks?

and you have to go around

by creating branch in Tick ?

[misty wharf]

🤔

If it's a latent task then I could see it potentially working that way

But if it isn't then it seems like it shouldn't need to be set up like that and returning from EnterState other than running should end the task

[shadow sapphire]

Is there a max number of navmesh volumes you can have on one level?
Is it better to have multiple navmesh volumes over only the specific playable areas, or one large volume covering everything?

[keen crow]

Rather a theoretical question. How does one implement stealth based on environment illumination using UE's built-in sight sense without manually placing volumes everywhere which denote how bright this piece of map is? 🤔 I mean so I can handle the situation when my NPC sees someone in a restricted area, I have my custom logic to build up the detection meter, but how do I take into consideration how illuminated the threat is?

[uncut rune]

I don't think there is limit and also it might be better to have multiple navmesh, reallly it's up to you how you prepare it so player can move or not move to certain areas

[light void]

What is the default cost of the NavMesh?

[floral hound]

Is there a way to receive an event when bot reach any point of navlink?

[uncut rune]

@uneven cloud just wanted to thank you for pointing me to StateTrees, I started to understand them a little bit more and seems like it's gonna be much easier and more flexible to do what I want with them, also thanks @floral compass and @misty wharf for notes, very usefull

[uncut rune]

Hmm, did they changed something in 5.3 + ? I'm trying to override function in the task, and it gives me event instead of function?

Shouldn't I have it like this?

[misty wharf]

There's been some changes to ST's in 5.3 I think, so it's certainly possible that changed

[uncut rune]

Okay

So How do I call now return node with the succesfull or running or failed?

I changed event to the Function

but I'm not able to edit Return Node like in tutorial

Does it mean that you don't have to specify right now that it finished?

Just when the whole event finishes it counts as done

[misty wharf]

If it gives you an event by default when overriding it then it means you can't really return any value from it directly

I recall you might have to call Finish Task when you want to finish it

this can be done from EnterState or from Tick or such as well

[light void]

I always have doubts, is the AIcontroller and the blackboard different for each AI, or is it the same for every AI?

[misty wharf]

One controller is spawned for each pawn and one blackboard is created per controller

Blackboard properties can be configured to be shared across all instances of the blackboard in its settings, but other than that they are not shared

[uncut rune]

So they removed these nodes with enum On Succesfull, On Failed etc?

and now it's this one

so this will either fire Sucess of on Failed

[misty wharf]

Yeah

You can't really finish the task with any other state anyway so I think this makes sense

If you want to keep the task running, you just don't call finish

[uncut rune]

Okay... so this is it. Finish task will lead to On State Succeeded or Failed

and what about State Completed?

[misty wharf]

Completed is either success or failure

[uncut rune]

Oh, okaaaay

[misty wharf]

I guess it's mostly a convenience feature so you don't have to configure the same settings for both success and failure if you want them both to result in the same transition

[uncut rune]

So I would basically call it like Event Start > Finish Task and then EventOnCompleted and add logic here? 😄

[misty wharf]

I don't know why you would need to add logic to event on completed unless you need to do some kind of cleanup but yes

[coral mesa]

Alright I wanna make a simple state tree with custom function. Basically would be something like

1. Check if Player is valid
2. If Valid then go to player
3. If close enough to player then attack otherwise move close to player again
4. If dead then go to Idle

dunno where to look for to make something like this

[misty wharf]

Look at the state tree docs, it shows how to set up a state tree with some tasks and things in it

[coral mesa]

https://dev.epicgames.com/documentation/en-us/unreal-engine/overview-of-state-tree-in-unreal-engine?application_version=5.3

Saw only this

didn't saw API or indepth talk about making custom states and more details about how to use it

it does say something but im mostly confused on this one

[uncut rune]

I think you can make it with Behavior Tree

[misty wharf]

https://dev.epicgames.com/documentation/en-us/unreal-engine/statetree-quick-start-guide?application_version=5.3

[vivid drift]

is it expected behavior that Finish Execute does not end execution of a task immediately? Like, calling it in a for loop does not break the for loop?

[misty wharf]

Yes, nodes cannot just exit out of the code with the exception of the return node when you are in a function

Nodes are effectively just function calls as you might have in C++ or other languages, so they have no capacity to exit the calling function. The Return node in case of BP functions is the equivalent of the return keyword, so it has this capability in that particular case

[vivid drift]

alright thanks

[coral mesa]

USTRUCT(DisplayName="DoTask")
struct EXAMPLE_API FSTT_DoTask : public FStateTreeTaskCommonBase
{
    GENERATED_BODY()
 
    using FInstanceDataType = FMyInstanceData;
 
    virtual EStateTreeRunStatus EnterState(FStateTreeExecutionContext& Context, const FStateTreeTransitionResult& Transition) const override;
    
    virtual const UStruct* GetInstanceDataType() const override { return FInstanceDataType::StaticStruct(); }
};

Saw this from your page @misty wharf didn't got this part about GetInstanceDataType. Why exactly you require that anyway?

[misty wharf]

It's just required for it to work

If you use instance data in your task

[floral compass]

Allows you to get data like this:

const UStruct* FSTTask_StateConfig::GetInstanceDataType() const
{
    return FSTTask_StateConfigData::StaticStruct();
}

EStateTreeRunStatus FSTTask_StateConfig::EnterState(FStateTreeExecutionContext& Context, const FStateTreeTransitionResult& Transition) const
{
    Context.GetInstanceData<FSTTask_StateConfigData>(*this).Enter();
    return EStateTreeRunStatus::Running;
}

void FSTTask_StateConfig::ExitState(FStateTreeExecutionContext& Context, const FStateTreeTransitionResult& Transition) const
{
    Context.GetInstanceData<FSTTask_StateConfigData>(*this).Exit();
}

[coral mesa]

what data FSTTask_StateConfigData should contain @floral compass ?

[harsh storm]

Whatever data you want that pertains to the task

[misty wharf]

It's probably worth noting that the Enter and Exit things in there are custom functions in the StateConfigData struct and are not something that's built in - the instance data is just a custom struct that you define yourself

[coral mesa]

is there any superspecific rule like must be derived from some class?

[floral compass]

In my case it looks like

USTRUCT()
struct MUGENTEMP_API FSTTask_StateConfigData
{
    GENERATED_BODY()

    UPROPERTY(EditAnywhere, Category="Parameter")
    UAbilitySystemComponent* AbilitySystemComponent;

    UPROPERTY(EditAnywhere, Category="Parameter")
    UAnimInstance* AnimInstance;

    UPROPERTY(EditAnywhere, Category="Parameter")
    TArray<FStateTreeStateConfig> Configs;

    TArray<FGameplayAbilitySpecHandle> AbilityHandles;
    TArray<FActiveGameplayEffectHandle> EffectHandles;

    void Enter();
    void Exit();
};

No such rule no

[misty wharf]

https://zomgmoz.tv/unreal/State-Tree/StateTree-InstanceData

[light void]

Does it still require C++ to put characters in teams? For perception of Ally, neutral and enemy?

[misty wharf]

Yes

At least for the builtin detection for it

[analog mural]

I have this issue with my AI where they stop detecting the player. This seems to only happen when I spawn them with SpawnActor. AI placed in the level functions fine. I printed successfully sensed in the bp and it's not false unless the player gets out of range. Yet the bt says that HasTargetActor is false.

[coral mesa]

#include "CoreMinimal.h"
#include "StateTreeTaskBase.h"
#include "SOM_StateTreeMoveToTask.generated.h"

//USTRUCT()
//struct FMyInstanceData
//{
//    GENERATED_BODY()
//
//        UPROPERTY(EditAnywhere, Category = Input)
//        int32 Foo = 0;
//};

UCLASS()
class UMyInstanceData : public UObject
{
    GENERATED_BODY()
};

USTRUCT(DisplayName = "SOM_StateTreeMoveToTask")
struct ALSV4_CPP_API FSOM_StateTreeMoveToTask : public FStateTreeTaskCommonBase
{
    GENERATED_BODY()

    virtual EStateTreeRunStatus EnterState(FStateTreeExecutionContext& Context, const FStateTreeTransitionResult& Transition) const override;

    virtual const UStruct* GetInstanceDataType() const override { return UMyInstanceData::StaticStruct(); }
};

Why this code results in error @misty wharf ? Am I doing something wrong here?

[misty wharf]

You are using a UObject, they don't have a StaticStruct member. Use StaticClass instead

If you want to use a UObject based instancedata, there's a builtin task or two that use it as well, check those for more examples of how it's used

[cinder crag]

Hello AI's Does state trees have debugging tools ?

[misty wharf]

It has a debugger in one of the menus when you have an ST asset open, and it logs into visual logger

[shy hare]

hey devs , please help , this ai should chase u and attack when he is close to the player but somethimes it is tryying to move but stuck at some points with some objects , u can see how he stops movement and jitter a bit (he is trying to move but can't ), as an example 0:17 or 0:41
why is that happening and how i can fix it? can EQS be a solution may be?

[harsh storm]

Looks more like nav agent properties aren't set up to support the larger character

Search for agent properties from Luthage in this channel. She talks about it from time to time.

[shy hare]

Luthage is a person? how can i find this properties?

[harsh storm]

You go to the search box of Discord, do From: Luthage and then search agent properties

[dense owl]

https://tenor.com/view/movies-the-heat-melissa-mccarthy-book-throw-the-book-gif-14851681

[primal vigil]

guys this is how my behaviour tree looks, is it not wrong ? it is blicking and idk why I think it should be just white and not blick or?

oh on video its not as visible but on my screen its blicking af

[floral compass]

If the task finishes immediately then the tree will restart search, that's the blinking

[light void]

I kinda need NPC to walk on these. Any easy solution?

[floral compass]

NavLinks maybe?

Just a guess, not sure about it

[dense owl]

More than one problem there I think

You would also probably need to add supported agents and lower the agent radius, if you want the navmesh to encompass the whole width of the escalator

[light void]

I presume this is in the capsule component?

[dense owl]

Project settings, navigation system iirc you should see supported agents

Capsule component does also come into play if it’s a char

I believe Luthage said capsule radius has to be at least 2 higher than the nav agent radius but I could be mistaken

[light void]

If I give an interface as a base class for a blackboard key, does it mean any class that inherit the interface?

[floral compass]

Might be tricky, would definitely try it first. Especially with BP interfaces

[desert parcel]

After installing Learning agent plugin and restarting UE5.4 it stucks here loading python script plugin at 75% any idea guys ?

[light void]

I got the BP interest spot
Which is inherited by the BPI InterestSpot
Move target in the Blackboard is a Bp_Interest Spot
I have a task with the variable InterestSpot which is exposed
But the Task in the behavior tree does not see the Move Target in the blackboard. Did I miss something?

[floral compass]

How are you trying to access the MoveTarget from the blackboard? Can't see that from your screenshots

[light void]

Move target is a BP interest spot and I'm trying to pass it to the BTT_Handle_InterestSpot Task. The other tasks I created managed to pass a blackboard key without issues simply by adding it as a variable for the task. But here it doesn't work.

Move target is setup when a character is created.

[floral compass]

Yeah but I can't see "MoveTarget" being used anywhere in those screenshots.

So I'm wondering how you're trying to access it, cause I can't see any reference to it.

[light void]

In the AI Controller, I add it. To then be Passed by the blackboard to the Task

[floral compass]

That's where you're setting it, what I'm asking is where and how are you getting it in your task?

Because all I see is the variable "Interest Spot" in your task which does not seem to be populated ever

What I would expect is something like

[light void]

That's the issue I'm trying to figure out why Behavior tree doesn't see "MoveTarget" as a valid value for "Interest spot"

[floral compass]

How do you expect "MoveTarget" and "Interest Spot" to be connected?

Those are 2 different "variables"

Not connected in any way according to your screenshots

Interest Spot, at least from your screenshots, is always empty

Btw don't copy paste the example I posted, there is a better way to access blackboard variables than "Make Literal Name"

[steel patio]

When i add a character with a custom orientation to a level, if it has an AI Controller (even a default one), the pawn get its orientation reset when i play the level. How can i avoid that ?

[light void]

I was under the impression that I had passed the blackboard key "Movement speed" in that manner to my task in the past. I just realized that I didn't pass the blackboard key at all but hard set it and moved on. So I was expecting the other thing to work the same way.
Problem solved.

[floral compass]

Would also be good to check whether the blackboard entry now really only allows objects that implement your interface..

[shy hare]

hey there guys , is there a way to make so that some AIs use one navmesh other AIs uses another navmesh? i got big and small ais

[flat sand]

Maybe a weird question but how do you organize your blackboard values(using blueprints)? Like if I want to access a blackboard value I have to use a name. I was thinking of a way to mitigate this because using names seems kinda problematic, especially if you wanted to make a change for whatever reason

[floral compass]

There are FBlackboardKey structs specifically to avoid having to hardcode names. Check how it's being used e.g. in Blackboard Condition Decorator

[flat sand]

ohh okay

thanks i'll look into that

[flat sand]

oh wait I think you meant something c++ related

[floral compass]

They're not exclusive to C++

Sorry I did use the wrong name though, you're right

[flat sand]

ahh I see yeah it happens haha thank you

🫡

[golden orbit]

Hi, why my RecaastNavMesh reset it's parametrs? Like Agent radius and Height

And every time it recalculates, will it do so in build version?

[misty wharf]

Did you configure the settings from project settings or directly on the recast navmesh actor?

[golden orbit]

Directly

[misty wharf]

Yeah do it from project settings. The settings on the actor are configured from there when the navmesh gets regenerated

[golden orbit]

Ah, i see

Thanks!

Btw, can i bake them somehow?

Like to generate them only one time

[misty wharf]

I recall there should be a setting somewhere which prevents it from being regenerated automatically in the editor

Meaning when you want to regenerate it you need to go through the Build menu to do it

[golden orbit]

Okey, i ill check, thanks!

[misty wharf]

They do get baked in that sense though so it won't regenerate in packaged games, unless you turn on runtime navmesh generation

[golden orbit]

Yeah, that's what i was curious about

Thanks again!

[dire jungle]

With EQS, is there a way to make a line of points to the left and right of an actor only (without front and back), so basically a grid that only extends to the sides, if that makes sense?

[misty wharf]

With a custom generator sure, not sure if there's a builtin one

[dire jungle]

yeah i was looking at the built in ones, they all seem to have some kind of radius

i guess i gotta look into making customs, thanks for stirring me in the right direction

[misty wharf]

If you use C++ you can check the code for the builtin generators, you can probably pretty much just copypaste one and modify how it generates the points

I'm not sure if it's possible in BPs at all

[dire jungle]

will have a look at this

[light void]

https://www.youtube.com/watch?v=vUy-UIEHqFA
I was checking this video, which uses an experimental plugin (GameplayBehaviorSmartObjects). Of course the video ignores it, since the video is about that plugin, but should I avoid it and give up on that tutorial? Is there somewhere I can check the feedback on that plugin and see if many people got troubles with it?

[misty wharf]

I use GameplayBehaviorSmartObjects in my project and it works fine

It doesn't do a whole lot as far as I can tell, basically you just get a GameplayBehavior class which you can use to create logic for how something uses the smart object

Since you're just working with standard blueprint stuff I wouldn't worry about it too much. If for whatever reason you need to replace it with something else, it should be reasonably straightforward

[light void]

It's weird. I know it should be safe, but the simple fact it told me to be careful stops me dead in my tracks :p

[bright timber]

Is this still the same in 5.4?

https://forums.unrealengine.com/t/ai-perception-sight-only-traces-to-middle-of-actor-capsule/875516

I'm in the same situation, need enemies to be able to detect the player if their head is poking above a crate but it seems they need to see the origin point of the player before they react ... would prefer to use the stimulus system but will default to a cone trace if I have to!

[misty wharf]

I vaguely recall there is a eye offset head offset or some other such value on characters which affects this but it might only affect the start position of the trace... otherwise you need C++ and IAISightTargetInterface (which is fairly trivial to implement if you know C++)

[coral mesa]

I always wondered what does EPathFollowingResult means?

Does it refer to finding the path and returning it? Or actually moving the Actor?

[uneven cloud]

You are incorrect. The capsule radius needs to be 1 less than the nav agent radius.

[dense owl]

Ah, sorry thx

[uneven cloud]

The step height on those stairs is way too high.

[uneven cloud]

The navigation system automatically picks the best fit nav mesh based on the agent properties.

[foggy moth]

I need to abort this selector from the blackboard BOOLEAN value - but its still executing it... what is the logic here?

my boolean values are false - is there a more appropriate way to handle this?

[dense owl]

Set != True

Set means it holds a value other than nullptr

Iirc there’s a Boolean decorator you can use instead

[lyric flint]

@uneven cloud You mentioned awhile back defining custom EQS / Blackboard code for selecting abilities. I imagine you set up a custom Blackboard key type -- if it's not too prying, did you also edit EQS so it could return something other than an Actor or FVector?

[uneven cloud]

I made a BB key for holding the ability handle. Then made an EQS item type for it. It's a lot of boilerplate code, but if you follow how the others are set up it's not that difficult.

[light void]

They're not stairs, they're escalators. I don't need the NPCs to step up to them, I just need the NPC to stop and wait at the bottom.

[uneven cloud]

Then you need to use a nav link proxy.

[light void]

Yeah, but then the AI doesn't stop there.

[uneven cloud]

It will if you add that functionality when they get to the link

[light void]

Interesting... Now the issue is to make it wide enough for them to reach the moving part of the escalator.

[coral mesa]

speaking of which

how do you make navigation agent

without touching the actor system?

Like making it for something like Mass/Other ECS solution?

[uneven cloud]

You need to have the agent properties struct.

[coral mesa]

explain? So far I know simple FindPathAsync but doesnt feel too good lacking avoidance and other stuffs

[uneven cloud]

There's a struct called agent properties. I'm not sure what is confusing about that?

[coral mesa]

i mean like using the struct like where to put it and how to call onto navigation system with all those avoidance mind

[uneven cloud]

It's on the movement component by default. If you aren't using the UE paradigm, then you need to figure out where it makes sense to put it.

[dense owl]

See what I told you about supported agents, with this correction #gameplay-ai message

[misty wharf]

Ugh, I'm trying to come up with a formula for calculating "item desirability" for my game and it's such a pain in the ass 🤦‍♀️

I guess it's basically similar to a utility score but trying to think of good ways of incorporating all the factors into it so they work in a way that does what I want is so complicated

Need to have like a "base score", eg. does the AI want the item at all to begin with, another score for outside factors that can affect it, and a situational score based on where the item actually is... and then it needs to also take into account the price of them item and whether it's considered to be too high

...and ideally this should also be slightly chance-based so that it's not a guarantee that the AI will always want it

oh yeah and there's also items of different types that could satisfy this score by different amounts

[floral compass]

I am entirely ignorant on the matter, but is it so that the more utility calculations you do the less "control" you have?
Since you're setting up fuzzy rules it's gonna get increasingly harder to get desired outcomes the more variables you have.

If so personally I'd probably try to keep the number of variables as low as possible. Otherwise my brain would explode trying to reason about all the possible combinations.

[misty wharf]

Yeah that's true, however the things listed here are generally something that would be part of the gameplay considerations the player would do to get some result they want... Eg. an advertising campaign or such is an outside factor the player could trigger, and placing drinks into a cooler would make the AI more likely to want to purchase it as opposed to it just sitting on a shelf

But there is certainly a possibility that maybe these things make it very complicated for no reason and the player agency from these things could be implemented in some other fashion into the system

[light void]

If I have a building with multiple floors, is there any particular reasons to split it in multiple navmeshes volumes? Or should I just keep it all on a single one?

[misty wharf]

As far as I can tell you'd mostly want multiple volumes if you have parts of the map where you don't want a navmesh generated

So by using multiple you can shape the area where it generates better or such

Or other design reasons, eg. maybe it just makes it easier to work with a volume for each area of your map as opposed to one ginormous one

[oblique basin]

I personally quite like to throw a bunch of variables in there to make things more unpredictable. The one thing I would say is to make sure you capture data when decisions are made so you dig in to how the decision was made, and make sure it's more or less what you had in mind.

[misty wharf]

Yeah I'll probably need to do that, currently I'm mostly playing around with ideas in spreadsheets to see how adjusting the values with different formulas affects the result

[oblique basin]

That's a good idea. Creating a control group.

We made an attack target system that took in 37 data points

Perhaps a little on the excessive side

[misty wharf]

:D

Yeah that sounds like a lot

In my fps project making the AI more complicated in that regard had a tendency of making the behavior worse for the type of more straightforward shooter it is

[oblique basin]

I read a study once on player reaction to various AI approaches to decision-making. They programmed about 10 different strategies from "target the least health" to "closest to me" to "random". 1) the players were terrible at inferring what the strategy was (the go-to was that the AI was somehow cheating). 2) the strategy deemed "most fun" was the random one. Take from that what you will.

[misty wharf]

lol, yeah there's always something like that... but I think it largely depends on the type of game. For something where the goal is to just let you shoot a bunch of guys and give you like a power fantasy thing you probably don't want the AI to be trying to be super smart, but in something more "tactical" in feel it would make sense for the AI to be like that

[floral compass]

If reducing the amount of variables is not an option then maybe their cardinality?
So just categorizing like low/medium/high and then mapping those to static score points for the selection

[full oyster]

Hi we're using a dynamic navmesh with navigation invokers on a map with world partition enabled. (UE5.3.2)
I keep getting warnings that meshes add an oversized dirty area and I have no idea why that happens or how to fix it without ignoring those obstacles in navmesh generation. Most of them aren't even very big

LogNavigationDirtyArea: Warning: (navmesh: RecastNavMesh-Default) Added an oversized dirty area | Tiles marked: 1 | Source object = StaticMeshComponent /Memory/UEDPIE_0_M0ZDOAAVNOC97P5GS7W72J6FD3.Worldmap:PersistentLevel.sm_Prop_185.StaticMeshComponent0 | Potential comp owner = StaticMeshActor

this is doubly interesting to me because almost all of the actors referenced aren't even close to the invoker range, it seems it's just whenever world partition loads or unloads tiles it throws warnings no matter if they affect the current navmesh area

[misty wharf]

I think crowd avoidance should work with any kind of pawn

maybe

Yeah not 100% sure - but I think if you use the crowd avoidance controller, and implement the crowd agent functionality so that it works correctly with your pawn type, it seems like it should work

[misty wharf]

C++

I would try it first with the crowd avoidance controller and see what it does with a non-character pawn

[signal island]

im having this bug messege using StateTreeAIComponent on cpp, LNK2019: unresolved external symbol "private: static class UClass * __cdecl UStateTreeAIComponent::GetPrivateStaticClass(void)" (?GetPrivateStaticClass@UStateTreeAIComponent@@CAPEAVUClass@@XZ) referenced in function "public: __cdecl ASpyAIController::ASpyAIController(void)" (??0ASpyAIController@@QEAA@XZ)

i added the module and all

[floral compass]

You need both

            "StateTreeModule",
            "GameplayStateTreeModule",

[signal island]

                "GameplayStateTreeModule"``` its already added :c

i tried to put on character and aicontroller but doesnt compile

[floral compass]

Did you refresh project files?
Other than that I have no idea :/

[coral mesa]

alright how exactly you pass actor data to state tree?

like I want to ref my player on state tree

[floral compass]

By using an evaluator

Or if you have the player stored in a variable somewhere you can property bind to it

[coral mesa]

how exactly I cant directly ref actors on level on the state tree

[floral compass]

Doesn't have to be on the state tree, can be anywhere

[coral mesa]

any good example?

like some sorta code?

[floral compass]

The AIController's PerceptionComponent could be one such place. It entirely depends on your use case and how you're getting the player.

Also whether you only have 1 player or multiple

[coral mesa]

just 1 player. Regardless i mean I am not seeing good ways to pass stuffs onto state tree. Atleast from what I know of...

[floral compass]

Evaluators and property binding. The latter being a very comfortable way to get anything into your StateTree.

[coral mesa]

basically just get something on runtime

[floral compass]

Here's an example for an evaluator

And here's how you use property binding to access anything your evaluator spits out

Bit buggy atm since you can't access nested properties, but that should be fixed by 5.5

[coral mesa]

alright alright what's the base C++ class for it?

[uneven cloud]

You do this by not having different scores as that makes it really complicated, but having things that modify the score.

[misty wharf]

Yeah I mean that's the gist of it but you have to determine how they modify it :)

I think I figured out a not terrible method of determining whether the AI thinks the item is fairly priced or not so at least that's something lol

Although now that I mentioned it, it occurs to me it would probably work better if that's a separate check all things considered 🤔

[uneven cloud]

RVO is in the CMC. Detour crowd is not.

[misty wharf]

But the problem with it is also partially that the level of how desirable the item is could potentially be used to allow for a higher price to be charged.... so you can probably see why this is annoying and complicated

[uneven cloud]

RVO and detour crowd are 2 different avoidance implantations. They are completely separate, but both do avoidance, just in different ways.

[floral compass]

FStateTreeEvaluatorCommonBase

[uneven cloud]

No. You should use one or the other. Detour crowd should work fine with a pawn.

[old plover]

I think I have the same problem, I understand that OnTargetPerceptionUpdated performs an execution pulse so it will not keep anything running until something changes, what keeps running and updating is the sense,(vision, audition etc.) I also need that once detected, a function keeps running until it goes out of the vision range.

[misty wharf]

Have a variable like CurrentTarget in your class, assign the target that's perceived into it. Then in Tick check if CurrentTarget is valid and if it is, do whatever you need on it

[open swift]

does the "abort lower priority" option work for a branch in a dynamic subtree to cancel a lower priority branch in the overarching tree that's running that subtree?

like if i have a sequence or selector, where the leftmost option is "Run Behavior Tree Dynamic" and a branch in that tree is set to abort lower prio

[dense owl]

No, branches above are higher priority

[open swift]

even branches to the right of the dynamic tree task?

[dense owl]

Not in regards to the run BT task itself but your decorator would have to be on the Run Behavior Tree task

Outside the subtree

[open swift]

hmm

im trying to make ability selection a dynamic subtree, so that the general flow of "use ability -> move to position -> cast ability" is on behavior tree that everyone uses, and the different ai just have different ability selection subtrees, but im having trouble with implementing a system where some ability selections should override the current running ability but others shouldnt (and should just wait until the next time we run the tree to select a new ability)

just having trouble figuring out how to let some branches abort the main tree but others not

[old plover]

Thanks, I was trying to avoid an Event tick, since in my detection I calculate illumination values and it is a bit costly, I was thinking of having a reference of the sphere that appears in the debug view, that way I can make calculations etc when the sphere changes position. That way along with the auto success range from last seen location it would update within the view range, but not on every tick. Any idea if the sphere is accessible in BP or c++?

[uneven cloud]

Why are you putting ability selection directly in the tree like that instead of a task or service?

[open swift]

i was writing it in c++ but i found that the ability priority system i was writing i was just remaking a behavior tree.

so i figured i would just make it a little tree dedicated to only ability selection

and just run that as a dynamic tree within my generic combat tree

[uneven cloud]

The sphere in the debugging is just getting the data from the perception info. You should be using the real data (perception info) and not the debug dump of it.

[uneven cloud]

How could that be even remotely remaking a BT? Now you need a BT for each AI instead of being able to share one.

[open swift]

i mean i have to make ability selection for each different ai regardless, why is it worse to make it a behavior tree than to make a stack ranking of abilities with different requirements (which end up jsut being decorators by another name) for each one?

[uneven cloud]

Why would you need to make an ability selection for each AI?

[open swift]

because they all have different abilities and different requirements to use them

[uneven cloud]

So?

It doesn't make sense to hard code that in the AI, when the different abilities can do that just fine.

[analog mural]

Right, but in my code I set the TargetActor variable in the BB when the AI senses the player. So while it's in range of the player, it should always be able to detect the player.

[open swift]

what do you mean? when i say ability selection for the ai, i mean the priority list for each ai for what abilities they should use. Like if I have 2 enemies that both use some generic "Arcane Blast" spell, they don't necessarily both want to use it in the same scenarios and at the same priority level. One of them might have other higher priority abilities and only use it as a last resort, while the other just uses it occasionally and has some melee abilities if it gets too close to its target. For boss enemies they might also only want to use it in specific phases. All of that kind of logic seemed like it would make sense to write as its own priority list, but when i started writing the priority list, it essentially just turned into "if this condition and this condition are met, use ability 1, if this condition is met instead, use ability 2" etc. which just ends up basically being a selector node with a bunch of decorators on the various branches, is it not?

[light void]

Alright, first time working with Navlinks here. I have an escalator. I want NPCs to only go 1 way in it, so I created a navModifierVolume on the elevator itself to remove the default navmesh that was built on it, added a Navlink that went from bottom to top, making sure Left was at the bottm and Right at the top. I set the Link on Left to right. I kinda expected the AI to just walk straight "toward" the Right link and thus scale the escalator, but it didn't. The AI stopped, not sure of what to do.
What am I missing?

[misty wharf]

Afaik you always need to implement the logic to navigate the link yourself

Just having the link just tells the AI "go here to get there" but how that happens is up to the smart link to implement

[light void]

According to the video I'm watching, no. As soon as the link is built, the AI just start walking.

[misty wharf]

🤔

Which video is that?

[light void]

https://youtu.be/iu7cjp1Gg7U?si=rTt8XI9KO4WBW1Cx&t=77
Granted it was UE4 and the ground is flat, but the dude has no navmesh in between, just places two links, and the AI start going through.

[misty wharf]

Where does that walk through the navlink? I see it jumping but that's been programmed into the navlink

Wait it was right in the start was it? lol

[light void]

At exactly eh timing the video should start (about 1.17).

Is it because the two spots have the same elevation?

[misty wharf]

Are you using the navlink proxy like he does or a custom link like later? 🤔

I definitely recall the proxy not really doing anything but maybe I'm mixing it up with a custom smart link

[light void]

I believe a Navlink Proxy

Now, I don't really mind, I setup a system where the NPC "Walks" straight toward the direction of the other link for a bit, wait for a bit then resume (while it may be unclean, it'll ensure the AI will start moving again if it gets stuck) but I expected it to...

https://tenor.com/view/it-just-works-tod-todd-howard-тоддговард-fallout-skyrim-gif-14803660

[misty wharf]

heh

yeah I mean I don't think anything's really changed with the navlink stuff since UE4 so it seems like it should work like it does in the video in that case

[light void]

Alright, at least I'm reassured it's not just me seemingly not being able to follow a 40 second explanation.

Worst part: It was working without the link and the Bound volume to remove the Navmesh :p But they could also go down. And it's supposed to be one way.

[misty wharf]

Well you might want to do it via a custom smart link anyway right? Cause you can have the AI actually step on the escalator, do a lil animation, etc. instead of just walking it down

Oh I see you just posted about this on the ue subreddit lol

[light void]

yep. While yes, I might actually wanna do it myself, I also want to understand how things work. If my assumption of something is wrong, I kinda want to learn still.
And also yes, I do post on the subreddit when I don't find an answer quickly here.

[misty wharf]

Yeah I'm kinda curious also 🤔 It seems strange it would behave differently like that

[odd violet]

Hello, don't know if anyone can help figure out how to get around this, I've been trying to create a small isometric game, with two player-controlled characters, one of them was going to have the ability to knock down destructible barriers. I've created a geometry collection for this door and added an Anchor field at the top, but after despawning the fractures the navmesh doesn't rebuild correctly, giving inconsistent behaviour when trying to go through it.

I've been looking into the RecastNavMesh class to understand how the navmesh building occurs, is there anything in this that can help me get a more reliable result? Thanks to anyone who's willing to land a hand in this 😄

[misty wharf]

I would try disabling can affect navigation on the destructible part

And/or set it up such that it generates a nav area which blocks the other character from navigating through it and only allows the correct one

Although it seems if you have runtime generation enabled for the navmesh it should regenerate

[odd violet]

Yes, I set it to dynamic, and I can see it regenerating the navmesh, but for some reason it never gets rid of those gaps even though the fractures are gone.

[odd violet]

Yes, that was going to be the next thing I was going to do, but the issue I've got right now is that no character can go through the navmesh when it is like in the picture.

[misty wharf]

Yeah if you turn off the affect navigation from the mesh it will allow it to generate the navmesh under it

[odd violet]

Wouldn't that cause the AI to try to go through the door even when it's still intact?

Oh wait, the collision with the door and the Character capsule collider would stop the character from moving though..

I'll try it right now

It seems to have worked although the character keeps trying to walk through the intact door and playing the walking animation. 🤔

[misty wharf]

Yeah it depends on how you want it to work. If it bumps into it you could have it stop movement, or set it up with a different nav area so that it won't even try

[odd violet]

I'll try setting up a new navmesh area inside the walled section of the level where the Character can't go, but I'd have to find a way to change this to a walkable area once the wall is destroyed.. 🤔 , is there maybe a way the Chaos system can tell the rest of the game when the geometry collection's fractures have finished moving/gone to sleep?

[misty wharf]

I would just do it with the wall piece itself

So you'd have f.ex. a collison box in the wall piece actor which is set to use a nav area that makes it impossible to navigate through it, and you hook up the events from when the wall gets destroyed to adjust the nav area to a navigable one again

[odd violet]

hook up the events from when the wall gets destroyed
Is this a chaos event I can bind code to from the geometry collection actor?

[misty wharf]

I have no idea but I would assume there must be some way to do it

If it doesn't have an event to tell you when it happens, then you could probably just trigger it simultaneously when you destroy it

[light void]

If anyone has any idea why this doesn't work, I'm all ears. I tried more complex ones as well, to no avail. I got two of them, one simple and another smart. Both are configured left to right, left being downstair. Just for trials, the smarter one has a function that makes them jump rather than move toward.
I'm also interested if anyone has a way to check if the AI at least tries to path with it. Thanks

[odd violet]

I'll look into this. I'm hoping there is, but I'll live it I can't implement this the way I want ahah 😄 . Thanks for helping, really 👍🏻

[open swift]

any way to debug a behavior tree being run by the "run behavior tree" or "run behavior tree dynamic" nodes? if i open the asset while the game is running it just says "no matching actors found" even though the main tree is running and is on the branch where i'm running a subtree

[gray minnow]

Is there any way to edit the parameters of AI Perception (Sight) at runtime with Blueprints? Like increase the radius if a stimulus is detected or enable/disable the perception when needed ?

[open swift]

to expand on this, i have a parallel node where the left branch just runs another behavior tree, and it doesn't seem to actually do anything

[misty wharf]

Try placing breakpoints on the nodes, and when running in PIE, try using the dropdown in the BT editor's top bar to select the appropriate controller. Sometimes it won't detect it right away. You can also try detaching from the pawn, and selecting the AI character you want to debug as this should also track the appropriate one in the BT editor

[misty wharf]

Not with blueprints, but it's fairly easy to expose this functionality to BPs via C++

Although you can enable/disable, just not tweak the individual settings

[open swift]

I tried all this, the main tree is running, and is on the correct branch in the debugger, but inside the subtreethe dropdown shows no options. chatgpt says that you can't use the RunBehavior or RunBehaviorTreeDynamic nodes as part of parallel nodes, so it seems I'll have to do something else

[misty wharf]

I wouldn't trust anything ChatGPT says but this seems plausible if it isn't working

[open swift]

i havent really found any other answers, but the chatgpt answer lines up with what i'm seeing 🤷‍♂️

[misty wharf]

I would try placing the Run subtree node outside of the parallel... if it works, then it seems the parallel is the issue

And yeah ChatGPT is occasionally correct but I would treat it as "assume it could be wrong, so verify its claims yourself to be sure" lol

[open swift]

yeah if i move the node outside of parallel and into a regular sequence it works

:/

bummer

dunno why i can't wrap my head around how to get the system i want working with behavior trees, its been months of trying to make something work, failing, and then just doing something else until I get to the point where I need AI in the game to test what i've been working on

[misty wharf]

What are you trying to make it do?

I've still not found any use for parallel in any of my projects :P

[open swift]

the way i want the ai to work is basically: each enemy has a priority list of "combat choices" which are just made up of an ability to use, an EQS query to run to get a move to location BEFORE using the ability, and an EQS query to run to get a move to location DURING the ability usage. both of the queries are optional, so if they aren't set for a choice, then the enemy just defaults back to some default movement logic. so basically Select Ability -> Pre-CastEQS -> Move -> During-Cast EQS -> Move/Use Ability (parallel) -> Restart

I wanted to run the ability selection in parallel so that I could mark certain choices as "high priority" which means if they become available while I'm doing a lower priority choice they just abort the whole sequence, while other choices won't do that and will just be chosen later. this seemed to me like I should just use the built in observer aborts stuff that decorators have, so i would just make the ability selection for each enemy a subtree that gets injected into the generic "use ability -> move -> etc." tree that everyone uses

luthage said this is a bad idea but i'm not sure how you get around doing either that or just writing the same logic but without a behavior tree, which seems silly since the ability priority functions like a selector node with a bunch of decorated branches that can abort or not (to me)

i've used this example before, but I would like to be able to write enemy ability selection like a wow priority list, where the same ability can be in multiple places with different conditions

[floral compass]

Behold my probably completely-unnecessary-but-I-can't-think-of-how-else-to-do-it parallel node usage and despair!

[misty wharf]

Didn't we talk about this lol

[floral compass]

Oh right that was you

Hope you still despair a little :p

[misty wharf]

As long as it isn't in my codebase it's not a problem

[misty wharf]

Hmm yeah hard to say, you could also run the selection as a service or such I think

[open swift]

maybe, i dont really want to select abilities on an interval though, i only want to select when i'm finished with the previous ability OR a "high-priority" ability becomes available and wants to interrupt the current ability

[misty wharf]

How would the high priority ability become available unless you're checking whether it's valid on some interval or such?

[open swift]

well ideally i would just have some delegate fire off so i don't have to check stuff on an interval or every frame

(if im not just going to use decorators on branches)

[misty wharf]

Right, well I mean the service could just listen for those delegates, or you could use something to update the BB which causes some decorator to trip

[open swift]

maybe, i think im just dumb but at this point i feel like it would be easier to just write the whole thing in c++ than try to contort what I'm trying to make to fit the behavior tree architecture that i apparently just don't understand

[misty wharf]

heh

[devout axle]

Hey guys. Any idea why RVO avoidance is not working with my npcs?

[rugged cloak]

Hello guys, I'm making a simple AI system with the PawnSensing. The issue is that, when the player go out from the Perphal vision angle, the AI instantly stops to chase the player, freezing completely on its local position. So how can I fix that? How can I avoid this? Could somebody help me please?

[latent cradle]

hi there, i m trying to make basic example with state trees in ue 5.4, and i canot get to work move to premade task, in debug alway says fail to move to, but dont know why, i tried, put vector or target actor both the same problem

[gray minnow]

Remove the sequence and place the delay and what follows after the AI Move to, basic out exec

[rugged cloak]

Something like this?

[gray minnow]

Yep ! Think about setting up your speed too, but that's how I did it, and it works, when I'm not detected anymore, my enemy goes back to patrolling

[rugged cloak]

Yes it works. However it follows me but it still freezes itself instantly when I go out from the pawn, like forgetting to see the player. It seems innatural. What I'm trying to do is to make the enemy AI remember my last location when I just came out from the pawn

[rugged cloak]

Do you have any idea? 🙈

[gray minnow]

Oh, I thought you just wanted to make it go back to walking after losing the player

[rugged cloak]

Ok wait no

[gray minnow]

then why do you need to remember the last location?

[rugged cloak]

I make you a video

[gray minnow]

to have it walk there before going back to patrol ?

[rugged cloak]

to show it

[rugged cloak]

Here we are sorry

This is what happen

When i go behind the pawn visual cone, it behave like lagging and then restart to move in a random location

[light void]

I think I finally figured something about my Navlinks. I managed to get it to work. The important part is the thin black arrow. Here I have the navlink set to Both ways, it works. They can go up AND down without too much troubles.

If I set Left to right, it works, they can go up without troubles.

If I set right to left, the arrow disappear (and does not appear on the other side) and the link does not work. For some reason, the game cannot understand it. It feels like something prevents the arrow from being created.

I'm starting to think that the issue is collision. The game probably tries to generate the arrow as the path of "the jump" and realize that there is something in the way and does not generate it.

[rugged cloak]

I solve it! Wire the ‘On Success’ pin back to the ‘Cast To’ node. So that whenever it succeeds it is re-triggered.

[tulip shard]

Hey guys, so I am trying to make an enemy move continually towards the player, I do this but rapdily firing off ai move to calls and this works fine as long as the enemy can reach the player. One problem I'm having is that as soon as the player is in a place where the ai can't reach, even just on top of a tiny rock, the ai will stop moving. I'd rather them still keep moving towards the player even if they can't reach them. I could probably brute force this with some logic that makes them go straight in the player's direction if the ai move to fails or something, but I just wanted to know if there's a way to do this with ai move to or some other node instead? Thanks in advance for the help!

[hasty basin]

pulling my hair out a little here. I have an AI state machine, as below. for whatever reason, it never begins running. it's assigned to the AIController, as I'd expect from that class (i.e. the AI specific state machine class) and set to start automatically. but it just never does.

docs are naturally missing for the component, but figured I'd see if anyone here knows what's what.

[uneven cloud]

What I mean is that it's certainly not the only way or even the best way.

[uneven cloud]

Why are you using pawn sensing, which was deprecated in 2016?

[uneven cloud]

Your problem is that the AI is moving to the target actor's location. Instead of finding a location close enough to the target they can reach. A better solution is to use the EQS to find a location near the target and update it on an interval.

[stray bobcat]

Hi All - I've got a problem where I'm using AI Move To function in a behavior task but when I switch to another behavior task the AI still keeps moving to the original Move To destination from the previous task even though it's aborted and is no longer running. Any ideas why the AI Move To is still functioning after the task has been aborted and how I can fix? Thanks!

[dense owl]

how are you aborting it?

[stray bobcat]

In my AI Controller. If my player is too close and in sight the AI should switch to a new branch "RangeAttack". When playing, it shows that the tree correctly switches to the new branch, but the AI is still moving to the desination of the old branch ("Return"). Here's the screenshot of my "Return" condition which has the Move To function in. Am I aborting it properly or should I do something else?

[dense owl]

call StopMovement if you want the Move to abort immediately. Otherwise all you're telling it is "don't move on to the next task, stop the branch there and move up the tree"

there's also a BT MoveTo task but afaik you can't change the acceptance radius dynamically, out of the box

[stray bobcat]

This seems to work, thanks. I just put stop movement at the start of my RangeAttack. It's weird as switching to other behaviors doesn't seem to have this issue. Anyway, appreciate the advice.

[dense owl]

other behaviours such as?

[stray bobcat]

Seek, Investigate, Idle etc. Anyway, no worries, the stop movement works great.

[floral compass]

What approach would be best for selecting the most fitting ability out of a set?
Almost sounds like utility thing already

[rugged cloak]

And what should I use?

[dense owl]

AI Perception System

[devout axle]

Hey guys. Any idea why RVO avoidance is not working with my npcs? I don't know what to try anymore, they keep bumping into each other and they get stuck. I can't get on with my game with the npcs like this

[brittle lynx]

Make them pass through each other and get on with the more important parts of the game. You can go back to this later.

[light void]

I'm now looking at having NPC interact with objects in the world. Sit in chairs, inspect stuff in shops, etc. Tutorial I've seen is about smart objects, but I've seen that it's still in beta. Is it safe enough?

I also saw the option of using components, but I am not sure of the limitations.

[obtuse igloo]

Hi guys! I'm trying to set up a smart object bed that my ai can use to sleep in but I'm unsure how I would implement the gameplay behavior of the object to add energy to the ai as they use it (ai is constantly getting energy replenishment from the bed as they use it)

Anyone have any ideas as to how I can structure this?

[potent loom]

If you're using GAS, I'd add a buff to the character for sleeping, and have a persistent AoE ability for the bed to replenish energy if they have the sleeping buff applied.

[devout axle]

Hey guys. Any idea why RVO avoidance is not working with my npcs? I don't know what to try anymore, they keep bumping into each other and they get stuck. I can't get on with my game with the npcs like this

[undone heron]

My AI is walking through the landscape like this. I'm using floating pawn movement

how can I fix this?

and they also like to float

[floral compass]

My first guess would be to not use floating pawn movement? Why was there a need for it?

[undone heron]

There can be hundreds of ai moving at the same time in my game and charactermovement was too expensive

floating pawn is a lot cheaper

[floral compass]

Not sure how to help there. I think the floating pawn movement is working as expected there afaik.

[undone heron]

is there another way to deal with optimization while using charactermovement?

when having loads of AI

[misty wharf]

There are a number of things that can be done to speed up CMC, in particular you can change it to use NavMesh Walking instead of standard Walking and some other things like that

But to make floating pawns stop floating, you would have to implement some kind of mechanic on them that "grounds" them, eg. keeps track of where the ground below them is and makes sure they stick to it

[vivid basalt]

Hi, my AI NPC perception has this issue, if my player roll quickly into a cover, the AI perception lost sight and then gain sight again, and stuck in a move to loop. But if i move into cover at regular speed, the AI can lose sight normally. Has anyone encountered this problem??

[undone heron]

Thank you!