gameplay-ai

[opal bolt]

I am not sure. I currently thing I do not want that.
So. In the end your are right, totaly. In the end, I want ANavigationData.
But ... EQS as I see, is using filter for this. Or I missunderstand the concept.
I think it works like that:

one moment

^^something I can select in this box. And as I understand, these are filters.

[pine steeple]

right but like i said, filter does not have a concept of NavigationData

[opal bolt]

So, you think it's not possible?

[pine steeple]

i can see its not possible using just a filter

[opal bolt]

hmm, ok, I still wondering but I know you have big knowledge. I have to think abou it.

[pine steeple]

what is running this EQS?

the pawn with the different navmesh?

[opal bolt]

Normaly I make much use of EQS Test pawns which are built in in ue4 to make the EQS ready. Then yes, it will run by and agent which is an AI pawn character.

Or... one moment. Perhaos I thought the wrong way around, and when the AI pawn is executing the EQS, then it simply use the NavMesh which fits to the supported agent by default...

of man, perhaps I simply have do do nothing right?

[pine steeple]

^

it should pull the correct navdata for that pawn

[opal bolt]

oh, f**k, hours for nothing. Just a misconception in my mind perhaps. Yes, UE4 could have built in to take the appropriate nav mesh when executing EQS with AI pawn. You are right. I am not sure, but I have to test.

Sadly, I can not test it with EQS Testing pawns then. But that's not so important.

[pine steeple]

yes you can

adjust the agent props for it

to match your bigger AI

and it should use the correct data (can breakpoint the function in the generator)

[opal bolt]

Did you every used a custom Recast Mesh for a supported agent?

Or do you also use the default ones?

I aks because I think, if I understand how to use this, this is also somethig I could use to determine on which navmesh EQS is running. Because in EQS Testing pawn I can select the same as in "Supported agent" configuration. But I did not find any good documentation and examples about this "custom recast" navmeshes and when/how to use

[fresh remnant]

any tips on optimizing behavior tree ticks when idle? The ticking is costing about 3-4ms of my frame time with 600 characters.

ideally I would want that down to 0

all its doing is waiting for an order/blackboard order set, but it's taking so much time

[ocean delta]

is there a way to get the AI to keep chasing the player even if losing sight of the player?

i'm looking at prediction sense but i'm unsure if that's what it is

[feral marsh]

Hey guys, how are you all doing today? I have a question and I don't know if that's the right place or not, I have an Ai that moves randomly and the animation plays normally but when added a statement to the move to it doesn't play the animation like for example its T-posing hovering to exact location, Now I don't know if that's a problem with the animation or not, thanks in advance | TLDR: Ai's animation plays normally but bugs out when added statement | Update: I tried this fix: https://answers.unrealengine.com/questions/821053/how-to-use-paragon-assets-for-ai-character.html but nothing... I do think its something wrong with the BT but I am not sure

[ocean delta]

anyone know why this AI's rotation is instant? it doesn't seem to be obeying bOrientRotationToMovement

[lyric flint]

Most likely the rotation works correctly, but your RotationRate is too high, so when applying the Delta, it appears to snap. I may be wrong.
As for chasing after losing sight, most likely you would need to fiddle with OnTargetPerceptionUpdated, and if the Stimulus.IsActive() is false, add some code to randomize some frantic patrolling on random points around the location when it lost sight

[ocean delta]

i'll check the rotationrate but i think it's rotating instantly regardless of my rotation rate. thanks for your suggestion regarding OnTargetPerceptionUpdated, i'll likely need to stop it from losing threat behind corners

okay, so i was able to get it to stop losing threat when it loses sight. my next problem is just the rotation rate but i guess i can tackle that at another time

Use controller rotation yaw was enabled 🙄

it's all fixed, thanks @lyric flint

[brittle coyote]

Hello guys! I'm trying to simulate the bee behavior and I want to increase a variable from the Blackboard of the behavior tree each time that a bee (getting the index value of the actor of the class array) hits a flower! I thought I've done it properly but still I get an error! This is the screen of the Blueprint. Does anyone know how to fix this?

this is the error I get BTW

[brittle coyote]

nobody knows?

[pine steeple]

Please be patient when asking questions.

[brittle coyote]

Sorry I'm just struggling 😄 I'll be more patient next time

[dawn crystal]

What is needed to create a Nav Mesh Bounds volume? I have a Cartoon Water Shader and I would like to make a Nav Mesh on the water

but the water doesnt have any collision by default

[dawn crystal]

or in other words, Is it possible to create a Nav Mesh Bound Volume at surface which doesnt have a collision???

[lament linden]

You said bee but all of these classes read ape. Is that intended?

[brittle coyote]

yes! Ape is the Italian word for bee 😛

[lament linden]

Ooh, nice ahahah

Looks like the blackboard is not initialized when you are trying to do the update

Can you print the blackboards first to see if this is the case?

[brittle coyote]

Yeah, Nav Mesh Bound volume doesn't have collision! For water you may use Physics volume

[brittle coyote]

Blackboard is running fine if I debug it in realtime mmm

[dawn crystal]

I will try this out

[dawn crystal]

Does Physic Volume correspond with Ai?

[brittle coyote]

yes

[dawn crystal]

great

[brittle coyote]

oh sorry nope! I've though about nav mesh volume

[dawn crystal]

yes

I have currently a nav mesh bounds volume

and I would like to make a Ai for ship with using a Cartoon Water Shader

[brittle coyote]

it should by default be set without any collision!

[dawn crystal]

the "water/ocean' doesnt have a collision

and my Nav Mesh cannot be created

thats why I am asking

[lament linden]

And is the blackboard key name also correct?

[dawn crystal]

Is there a possibility to make a something like nav mesh, which can allow the Ai to move to location within the Nav Mesh

[brittle coyote]

I guess so! Let me double check it

[dawn crystal]

I cannot have a collision set up at Water shader

Water actor etc.

[brittle coyote]

never tried a Nav Mesh and physics volume together so I'm not sure what happens

[dawn crystal]

hmm

ehhh, so I am gonna to test a kind of cases

[brittle coyote]

I'm sure the litteral name is right because if I decide to use a specific index for the class such as "0" it perfectly works

[dawn crystal]

maybe something will works

[lament linden]

Hmm. Why do you increase the blackboard value for all bee's when one bee hits a flower?

[brittle coyote]

because I need the bee to get back to the beehive as soon as it gets enough pollen

but I want to update only the specific index of the bee who's hitting not all of them

[mighty mesa]

Hello. I can use the blackboard and the behavior trhee using a pawn and not the character?😬

[vast relic]

Yes

[earnest kelp]

I'm trying to get the ai to predict where to shoot the player so I've implemented this code but it doesn't seem to work. The code is fired straight from the behaviour tree, it fires but it doesn't see to predict where the player is. Thanks!

[pearl flint]

So i have a auto generating map but my ai cant go till the and and stucks at the second room and cant go more but i did nav mesh bounds at the whole map so why is this happening?

not moving more than this

this is the bp of the ai

[misty wharf]

Check if your navmesh is generated on the new areas of the level

[pearl flint]

@misty wharf it generates the level map when i touch to a trigger box so idk if it updates to that place or not

but i did nav mesh to the whole map

[misty wharf]

Okay, you can detach while you are in play mode, then click the "Show" button on top left of the window

choose Navigation from the Show menu and you should see an overlay where the navmesh is generated

[pearl flint]

lemme check

nope it isnt generating for the new levels

[misty wharf]

If you haven't enabled it, change the navigation mesh Runtime Generation option to Dynamic in your project settings, that should probably fix it

[pearl flint]

lemme check

@misty wharf is this alright?

[misty wharf]

Yeah, Dynamic should make it regenerate it at runtime when geometry changes

[pearl flint]

it works tysm :)

[pine steeple]

glad you sorted it :), be wary that adding new navmesh tiles can cost a bit, so tweak your tile size and cell sizes to get the biggest values that still allow for good pathing

to reduce the generation time

[misty wharf]

Does that get worse with overall size of navmesh, or is it primarily affected by size/complexity of the newly generated areas?

[pearl flint]

wdym as cost?

[pine steeple]

generating navmesh costs game thread time

so if you generate a lot of areas, you will get hitches

[pearl flint]

owhh

sorry im new at this but i will take your advice thx :)

[pine steeple]

yes, the quicker your navmesh generates, the smoother for players

[misty wharf]

Sounds like it's maybe more constrained by size of the changed areas 🤔

My game will have to do a whole bunch of regeneration since the player can build and move things about, so far it really isn't noticeable at all :D

[pearl flint]

mybe ur pc is powerful?

[clever skiff]

anyone able to take a look at my ai. i have it set to play an animation if it at a certain distance. the behavior tree fires the branch where the montage is set to play but the montage does not play. do i need to set up the montage in the animation blueprint where i have the walk and run state.

i cant seem to find a solution

[misty wharf]

Not really an expert on animations, but maybe try disabling the other animations so there's no animations whatsoever, and see if the montage plays then

If the montage plays when the rest of the animations aren't ran, then it seems to suggest that the other animations are taking priority over the montage and you might need to do something about it

If it doesn't play, then it seems that your BT task most likely isn't actually triggering the montage correctly

[pine steeple]

@misty wharf on my pc the navmesh generates fast, but on older pc's they will feel the hitch

which is why we have testers with different spec pc's

[misty wharf]

Okay, good thing some of our testers aren't running the fastest PC's so we can ask them to see if they notice anything :D

[pine steeple]

yeah best way

[misty wharf]

It probably shouldn't be too bad even if it hitches a bit, since it would be only done when you place something down, so you're kind of completing an action and it probably hides it a bit if so

[pearl flint]

i use 8gb ram and i think it can effect a lot in generally unreal sometimes crashes when calculating things

[pine steeple]

8gb ram is pretty low for UE4 development

[pearl flint]

ik

[pine steeple]

my pc runs at 20-32gb ram use majority of the time 😄

[pearl flint]

my pc is 6yr so LOL

[pine steeple]

ah, time for an upgrade? 😄

[pearl flint]

yea :D

[pine steeple]

@clever skiff your animation BP, has to have a slot node

montages play through this slot node

[misty wharf]

My PC's 4-5 years old at this point, but it was pretty high spec when I built it so it's still fine :P

[clever skiff]

ok uk. i believe that the only part i miss was setting up the slot for it.

ill try to do that now and see where it get me.

[lyric flint]

can you add actors to rvo avoidance?

ive got actors I want my ai to move to but theyr blocking themself with the navmesh

see chair barrel and trees

[fresh remnant]

@lyric flint you can add blockers with crowd avoidance. What do you mean they are blocking themselves? Are they set to generate navmesh obstacles?

[lyric flint]

they are yes

of I dont my ai will just walk into it

do i just turn off navmesh gen and use blockers?

[fresh remnant]

what do you mean blocking themselves though. Which ones are set to blocking, the trees or the people?

you should do navmesh gen on the trees, RVO isn't enough to block fully. But on the people, you should turn off nav mesh gen if you have them on

[lyric flint]

stuff like chairs

it cant move to the location cause its outside the navmesh

crude way is to add 100 to the Y Location so the location is inside the nav mesh

[fresh remnant]

you can add that as a blocker for RVO still

as well as navmesh gen

[lyric flint]

how do i add it as a blocker?

is there a node?

[fresh remnant]

I think they also need to be nav agents

but kind of forgetting

yeah if I'm remembering correctly, you need it to be a nav agent and set its flags to obstacle only

I'm not sure if there's a node for that, I set it in the crowd following override of an object. These are the states: enum class ECrowdSimulationState : uint8 { Enabled, ObstacleOnly UMETA(DisplayName="Disabled, avoided by others"), Disabled UMETA(DisplayName="Disabled, ignored by others"), };

void UNovaCrowdComponentOverride::RegisterCrowdAgent()
{
    UNovaCrowdManager* CrowdManager = UNovaCrowdManager::GetCurrent(GetWorld());
    if (CrowdManager)
    {
                SetCrowdSimulationState(ECrowdSimulationState::Disabled); <-- Set Simulation State here
...

[lyric flint]

oh

[keen crystal]

what can I do to prevent pathfinding on this couch?

I feel like I already set the relevant collision flags

alternatively I can set the agent step height lower but I get other problems

like I've no idea why this mesh gets this pathfinding

[fresh remnant]

@keen crystal make it a navmesh occluder

@keen crystal https://www.youtube.com/watch?v=wpyOZbyxQE8

[lyric flint]

@fresh remnant youre good with AI I guess? 😛

[fresh remnant]

no I just happen to have dove deep into this navmesh stuff

[lyric flint]

aah

[keen crystal]

thanks, I gave that a try and it didn't work, I ended up solving it by reducing the granularity of navigation

[fresh remnant]

I don't think that's a great way to approach it, that means if you have a bigger object, it's still going to do that. You definitely will need nav modifier volumes working in the long run

[keen crystal]

well, it's weird, I added a navmesh modifier and tried null, obstruct, etc, none of it did anything

[fresh remnant]

you may have to rebuild ur navmesh, depends if you have dynamic navmesh generation on

[keen crystal]

yeah I've been rebuilding navmesh after trying every option

[fresh remnant]

What are you using as the collider @keen crystal , maybe you can also move it closer to the navmesh (Z coordinate wise)

@lyric flint that's typical of RVO, rvo doesn't care about nav mesh bounds

@lyric flint are you using regular CMC?

crowd avoidance

but sometimes, physics will do it too

yeah, by default it doesn't do well in a lot of these cases..so if you override the CMC and make your own, you can constrain it to the nav mesh

you can just inherit off default CMC though

and just rewrite part of the PhysWalking or NavWalking function

here's the code to constrain:

hmm sec..more code than I expected

You're about to move to AdjustedDest:
// Constrain it
RecastNavMesh = const_cast<ARecastNavMesh*>(Cast<ARecastNavMesh>(GetNavData()));

DestNavLocation.NodeRef = RecastNavMesh->FindNearestPoly(AdjustedDest, Extent, nullptr, this);
if (DestNavLocation.NodeRef != INVALID_NAVNODEREF)
{
    if (RecastNavMesh->GetClosestPointOnPoly(DestNavLocation.NodeRef, AdjustedDest, DestNavLocation.Location))
    {
        AdjustedDest = ConstrainedDest;

that's the basic part of it, so there's one problem here that I had to fix, find nearest poly doesn't always find the nearest poly with the closest point

so if u just do this, sometimes it gets stuck on poly borders

because it finds the wrong closest poly and constrains it to that poly

so you have to iterate through neighboring polys IF your constrained dest does not match your adjusted dest(constraining happened)

Here's the code for that:

                float Dsq = FVector::DistSquared2D(AdjustedDest, DestNavLocation.Location);
                if (Dsq > 1.f)
                {
                    TArray<NavNodeRef> Neighbors;
                    RecastNavMesh->GetPolyNeighbors(DestNavLocation.NodeRef, Neighbors);
                    float smallestConstraint = Dsq;
                    FVector ConstrainedDest = DestNavLocation.Location;
                    // Find least constrained but still constrained
                    for (auto& PolyRef : Neighbors)
                    {
                        FVector ConstrainedPoint;
                        if (RecastNavMesh->GetClosestPointOnPoly(PolyRef, AdjustedDest, ConstrainedPoint))
                        {
                            float Dist = FVector::DistSquared2D(AdjustedDest, ConstrainedPoint);
                            if (Dist < smallestConstraint)
                            {
                                smallestConstraint = Dist;
                                ConstrainedDest = ConstrainedPoint;
                            }
                        }
                    }
                    AdjustedDest = ConstrainedDest;

also, neighboring polys in my case are gauranteed to be "crossable"

actually can combine those two code blocks, it wouldn't let me paste the whole thing

yeah took me a while to figure this out

And lastly I think, u may or may not want to use the Z value of that adjusted dest, because navmesh Z is different

[mighty mesa]

For fly ai I need to set the ai controller mode to fly? I have try with behavior trhee and set the ai pawn to can fly but the ai pawn go down and after move on plane.. I don't understud why can't fly 🤔

[rigid portal]

If I have 2 guards, and I want 1 to patrol a path, and the other to be on a guard tower, do I need 2 AI controllers? 2 Blackboard and 2 Behavior Trees? Or can I have 1 do both behaviors of the guards

[feral marsh]

Hey guys ,how are you all doing today?, I am having a problem with my behavior tree and the AI which doesn't play animation on "MOVE TO" node : https://forums.unrealengine.com/development-discussion/animation/1862538-animation-doesn-t-work-on-paragon-characters-how-can-i-fix-it

@rigid portal I will suggest you making a blackboard variable which will be true or false if he is a tower or patrol and the AI behavior tree will act by these statements

[rigid portal]

Oh, ok. So maybe tag an agent

[feral marsh]

Sure try it

[rigid portal]

Ok, will do. Thx

[warm dagger]

The only difference I see is that you add an attacking state. Do you do your attack animations in an animation blueprint and possibly are setting a boolean true so it can transition to attack animation and then you are not setting it false before moving to the random location found?

[feral marsh]

The attack animation is a AnimMontage

It doesn't have a transition or any boolean just a play montage node

[warm dagger]

I do notice one thing you may want to edit though. One state is distance <= 300 and the other is distance >= 300. Only one should have the = with it. So <= and > or vice versa.

[feral marsh]

May I ask why is that?

[pine steeple]

i dislike animbp playing montages

Montages should be played at the callsite

not in the animbp

[warm dagger]

I'd assum his task is calling the montage, I mentioned the animBP, hehe.

[pine steeple]

breaking encapsulation

[feral marsh]

Yeah the Task is calling the montage,

[pine steeple]

the task is calling AnimBP->PlayAttack

which then plays the montage there

right?

[feral marsh]

hold on i will double check

[pine steeple]

maybe show some more relevant information

[warm dagger]

Yeah, seeing inside them tasks would help.

[feral marsh]

Sure thing

2 min

[warm dagger]

Usually when the animations stop playing on movement it is because the animBP is confused, hehe.

Which is why I defaulted to asking about transition boolean not being reset correctly.

Does your code ever pause animations or montages?

[feral marsh]

Nope

The attack task ^

Is it ok? or is there a problem in the code?

[rigid portal]

When I tested this sometime ago, the animbp stopped because if was interrupted by the PlayAnimation

[warm dagger]

You are using play animation which changes your animation mode.

[feral marsh]

ohhhh ok

[warm dagger]

You will need to switch your animation mode back to use animation blueprint after the attack plays.

[rigid portal]

Ahhh ok

[feral marsh]

Thank you for the explanation

[warm dagger]

Or use an actual play montage node and make sure to add the slot to your animBP.

[feral marsh]

Will do, much thx @warm dagger

[pine steeple]

^

[warm dagger]

This node gives much more flexibility and you can make it so your attack task only ends when the animation actually finishes.

[pine steeple]

montages are meant for this type of thing

[warm dagger]

You can also use notifys to trigger that spawn projectile instead of relying on hard-coded delay timings.

[pine steeple]

tho you have to be careful with that, sometimes have the spawn time separate can guarantee it spawns. Depends how well your montages are setup and if you use branching point.

[warm dagger]

Lol yeah, I have had to slow down montages to make sure notifys trigger at the right moment and not during the next iteration of the montage.

[feral marsh]

@pine steeple Noted ty . @warm dagger I will look forward to it, much thx for the explanation 🙂

[rigid portal]

I created a array with Agent ID. I have 3 characters, set with id 1, 2, 3

i want agent 1 & 2 to do the task while 3 just stands around.

With this setup, only the first item in the array, ID 1, does the task. the other 2 stand around

How would I get agent 1 and 2 to do the task?

FIXED, nmv 🙂

If there is a better way, ping me please! I'd love to learn

[ocean delta]

this is probably a dumb question, but is it possible to create cpp tasks and decorators instead of blueprint tasks and decorators?

[lyric flint]

Absolutely! but why? anyways, take a look at Developer\AITestSuite\ In your engine source for more info

[ocean delta]

it's probably not necessary, but almost my entire project is in cpp and some things i find it more intuitive to express in cpp

[ocean delta]

good call

[lyric flint]

I agree, but it doesn't hurt you to visually see the flow of your AI either 😄

that's why, at least during development, it's not a bad idea to use the visual BT

[ocean delta]

so the only thing i'd be putting in cpp would be the decorator itself, not so much the BT

i'd use that cpp decorator inside of the BT

[lyric flint]

but of course, you can do everything in C++, I've done it before as well

[ocean delta]

i definitely do NOT want to put the BT into CPP

that sounds like a nightmare

[lyric flint]

you can mix and match as your heart desires 😄

well, sort of.. 😄

Kaos is a strong advocate of the balance between C++ and blueprints. I tend to be more C++ey than average, but he's also not wrong, as unreal engine was designed for these blending and balance. But if you are an indie lonely dev, then whatever works for you!

[ocean delta]

if i get this right, i won't be an indie lonely dev forever 😅

[orchid agate]

why when i use the move to node and the ai's path is blocked by a door/wall does instead of the movement failing it succeed instead and move on with the behaviour tree instead of going back up the tree?

[manic karma]

Perhaps the blocking is hooked up to return success

you could try creating a derivative and overriding a block to return failure/abort

[orchid agate]

thanks ill have a look into it 🙂

[fair zealot]

:triangular_flag_on_post: Aditya Raj#0050 received strike 1. As a result, they were muted for 10 minutes.

[unborn jungle]

Is there anything happening in the default AIController / Character code that would override the velocity of LaunchCharacter() ? I have an enemy that launches which works fine most of the time but occasionally the launch will only have velocity in Z as if the X and Y components were cleared by something else like the AI controller. Debugging the vectors going into the launch function, there's definitely plenty of velocity in X and Y in these cases. This "override" sometimes happens mid launch so it starts off fine but then suddenly loses the velocity. I have triple checked that no move to functions or anything similar are being run at the time of the override

Could SetFocus or anything like that be interfering with velocity?

[pine steeple]

no

velocity is all done in the CMC

not sure why it would not work on occasions

[unborn jungle]

Seems to be related to this: https://answers.unrealengine.com/questions/53382/is-the-launch-character-node-interrupted-or-overri.html

[deft sedge]

@ocean crystal @pine steeple had to go all the way back to 2018 to see any examples of run behavior dynamic. Do you still use this method? What are the draw backs? Do you have an example somewhere I can look at?

[pine steeple]

that could be possible

tho they are normally accumulated (the launches)

[deft sedge]

oh look at that, you're still active lol

[pine steeple]

Dynamic BT's with tags?

[deft sedge]

yes

[pine steeple]

one issue i had with them is if the BT restarts, it will loose its dynamic assigned BT

other than that i use them a lot

[ocean crystal]

Oh wow you're a spelunker. No, I don't use it because I don't do as much AI work lately. I don't have any examples publicly viewable (besides whatever was posted in 2018)

[deft sedge]

thank you

[pine steeple]

but you normally just call SetDynamicBehaviour on the behaviour tree component

with the tag, and the BT to run

[deft sedge]

where is somewhere you use this kind of thing? I currently have nested BT

[pine steeple]

nested BT?

like this?

[pine steeple]

i keep that for non dynamic stuff

but i only inject dynamic stuff into specific nodes

as they have a slight cost penalty

[deft sedge]

maybe I'm not understanding somthing. What is the "dynamic" aspect of these?

[pine steeple]

you can change them in code

or in bp

[deft sedge]

change them how?

[pine steeple]

say i had this node

and that tag

[glossy spire]

@deft sedge just to butt in, I use dynamic BTs for enemy combat skills

so that they can choose from several

[pine steeple]

i can do this and switch what BT is in use

[deft sedge]

is the point of this that you can start the behavior somewhere in the middle of the tree already and skip the top layer of checks or something?

[ocean crystal]

I would drive this injection through data (tables/asset)

[pine steeple]

^ that is what i do

[ocean crystal]

the point being that you sort of have a meta-behavior archetype

and then your specific AI will do a different sequence (maybe)

So this is a silly example, but you make a BT for passive mobs, neutral mobs, and hostile mobs... then you can spawn a hostile mob or passive from the same AI data but maybe the passive BT only ever runs the patrol or idle path

and then any given creature can have a defined attack sequence (or a set of them) but it would only be used if you didn't have a passive instance of that creature

SpawnMetaAI(UHostileBTSource::Get(), RandomMobFromRegion)

what do you use this for, @pine steeple, since you actually use it?

[deft sedge]

I'm not sure I see a difference between that and having a tag check in a decorator

[ocean crystal]

it would mostly be an organisational difference

you can have a massive BT and tag check a lot

[glossy spire]

it keeps your trees from becoming insane

[pine steeple]

i have a generic BT which runs behaviours injected in, which are pulled from the monster so if i need to do specific things per monster type, i can

well from the monsters data table

[ocean crystal]

designers like a BT field for, say, MobPatrolBehavior instead of a gamplay tag container which can have that tag

[pine steeple]

makes changes also easier, as i don't hardcode a lot of stuff into BT's rather pull it from DT row, meaning i can alter behaviour without altering a ton of BT's

considering we have 30 different monster types

it would become unwieldy doing it the traditional way

[deft sedge]

wouldn't the regular run behavior tree be the way around that?

oh wait

[pine steeple]

thing is, a lot of things can be hardcoded (like ranges, wait times, etc)

i pull stuff out and made custom nodes that pull from the monsters behaviour DT row

[glossy spire]

lets say you had potentially 40+ types of attacks, depending on the monster. You dont want a bunch of decorators deciding which tree to use

[pine steeple]

^

monster knows what attack its doing

injects the correct attack bt

and runs it

[deft sedge]

so you're likely grabbing a montage or something to play then from that data table?

[pine steeple]

no we use abilities for that

[deft sedge]

mmm, abilities, my old nemesis

[glossy spire]

since its a whole BT, it can be moving, targeting, montages, or whatever

[deft sedge]

if I try and put this in the scope of a splinter cell game (mixing between stealth and full on assault style game play) this sounds like it could make my life easier, but I'm still not exactly sure how this works.

I'm using ai perception to check for sight and hearing ( currently in the controller, but probably should do a service ) and that sets a handful of BB variables and some tags on the character itself.

@pine steeple I see in you snip above that most of your nodes end in regular run behavior tree, not behavior tree dynamic.

If I get to the end of a branch where I want my guy to attack, I end that branch with a behavior tree dynamic, which is meant to contain my variations yes? I call that set dynamic subtree in a task? from within the character? I don't really understand the flow here.

[ocean crystal]

I don't know that you would want to use it to change between alert states, that would be built into some common BT

[pine steeple]

this is a specific to that monster, that bt was injected in

i don't inject everything, just what is required

[deft sedge]

some of my variation could come from the character type, but also the weapons they are holding

wouldn't I want to use dynamic behavior if the environment has changed or something like that?

[glossy spire]

What I do is use one top level tree for all enemies. This tree decides if they should patrol, attack, investigate, etc. Then, after they know what KIND of thing to do, they run a task that selects the variation. That's the dynamic tree.

So I have a dynamic patrol, dynamic attack, etc

[deft sedge]

yeah I think it just clicked how it works as you sent that

so I essentially "replace" that slot. The tag on defines where the slot is then

[pine steeple]

Yes

[deft sedge]

hmm. is there a performance draw back to using this?

[ocean crystal]

@deft sedge yus

[lyric flint]

@pine steeple quick question if you dont mind

how the fuck do decorators work? lmao

😭

What I would recommend, is for you to solve a real-life situation mimicking a behavior tree. This is a very good exercise for you to understand the proper flow. So when you have some time take a paper notepad and every once in a while ask yourself one question: am I hungry? this is your service.
If the answer is false, meaning you are not hungry, don't do anything. If the answer is true, meaning you are hungry, trying to solve the problem

For example: condition Stage: are you in your room, are you in the kitchen, are you out and about. These are decorators

If you are in your room, what is the sequence of Tasks (actions) associated with this particular decorator being true

tasks: stand up, face the door, opened the door, head downstairs

and so on

after you do this exercise in real life while taking accurate notes in your paper notepad, it should become clearer and easier with some practice

and of course, have fun learning

and yes, I know I'm not Kaos, but I hope you would consider my suggestion 😄

[deft sedge]

how bad a cost penalty?

[pine steeple]

probably not noticable for 10-20 ai, but when your running 100 AI, i noticed a slight cost increase of around .2ms

[ocean crystal]

Kaos can be more specific

[pine steeple]

as it does some additional stuff to get the dynamic BT

but yeah, i optimize my AI highly, so the more i can save the better

which is why i use dynamic only in certain places, and use static if makes sense

[deft sedge]

ok so in this case that's fine. In my horde I probably wouldn't then

[pine steeple]

i can support 150 AI at around 3ms game time (my budget for AI)

that is when they are crowded around a player and moving

if they are away from player (not visible) they run at about 1.2ms for 150

very rare you will get 150AI bunched into players

that is total cost, including BT, Movement, pathing, etc

[patent hornet]

either the AI die quick, or players die very quick scenario

unless Kaos uses them cheats 😄

[pine steeple]

yeah 😄

thing is as soon as they die, i turn off nearly every system

so they cost nothing when dead

[deft sedge]

I can render 500 without a problem, just want to make sure i don't have cpu becoming the bottleneck

[pine steeple]

500 AI moving with CMC?

[deft sedge]

yep

[pine steeple]

🤔

average CMC tick (non optimized is 0.03ms per AI)

that would be 15ms game time

[patent hornet]

believes starkium is doomed there

[pine steeple]

and that is on my spec pc

[patent hornet]

which means 40 on potato gaming laptop

[pine steeple]

even if you got lucky and it was only 0.01ms per AI that is still 5ms

then you have BT, Perception (if you use it), character class tick, controller tick

[deft sedge]

uses empty character with no skeletal mesh and then has an HISM with Vertex animations set to the location and then custom collision detection system on top AND THEN uses monotick plugin to reduce cpu time

shipping build is like 4-8 ms total depending on the scene

[pine steeple]

yeah you loose a lot of flexibility tho

[deft sedge]

yes

but that wasn't the question

[pine steeple]

we have 30 different monsters

also multiplayer game not sure if yours it

is*

[deft sedge]

right, like I said, I can use it for the stealth game scenario, but not a zombie survival scenario. Two different projects

[pine steeple]

yeah well if it works, its good

tho 500 ai at a time in game, is a bit overkill

[deft sedge]

for the zombie scenario there's not a lot of variation so hard coded is fine

[pine steeple]

look at CoD zombies

[deft sedge]

can go higher if I switch to pawns

[pine steeple]

they have a max of 50is at a time

[deft sedge]

do I need to? not at all. doesn't increase immersion at all

but I wanted enough numbers to make an open world map feel full

[pine steeple]

but you can do other tricks

like spawn them when the players gets in a certain range

kinda thing

[deft sedge]

sure, they are pooled too

[pine steeple]

we don't pool our AI

we just destroy and create new

[deft sedge]

that has an impact on low end hardware

I'm developing for oculus quest

[pine steeple]

depends how heavy your classes are

ah yeah makes sense

we are targeting desktop

[deft sedge]

yep, so I fight for every little thing

https://cdn.discordapp.com/attachments/346032196714233856/795776070489079828/unknown.png

shipping build is way lower

[patent hornet]

should just fake those with niagara

until player starts interacting

[fresh remnant]

CMC if you use nav walking really helps. I also disable tick when idle

thing that hurts CMC the most after regular phys walking is overlap checks during movement, from what I've seen, so if you say, do ur collisions mostly with crowd avoidance and nav mesh, u can almost turn it off

this monotick looks interesting, is it just one object ticking for others..?

[wary ivy]

I guess it's inspired by the sea of thieves tick optimization presentation?

if someone makes an optimized character and character movement component that behaves mostly the same (acceptable if it only walks on navmesh too) I'd be willing to pay for it 😛

[static crater]

Hi hello, im trying to spawn navmesh bound volumes using c++, anyone knows how to visualize the bounds? (so i can check they are well placed)

command 'show bounds' does not make my navmesh bounds in editor visible

[manic karma]

you're trying to visualize them in-play?

[static crater]

yep

[manic karma]

I'm sure there's a command to show the navmesh in PIE

not sure about seeing the actual bounds

[static crater]

its show navigation but that actually visualizes the navmesh itself

however so i noticed my spawned navmesh bounds are not properly setup anyway

[manic karma]

I guess you're looking for something more fine tuned than just the navmesh being correct

[manic karma]

ah

well.

[static crater]

it should be like

[manic karma]

set the brush in C++ code then

[static crater]

Right, ill have to dive into brushes than, never created one

[manic karma]

it will just be a struct containing the information in the second picture

the navmesh bounds volume will have a function like SetBrushSettings or something

[static crater]

hhm, got any point to some example code?

[manic karma]

https://docs.unrealengine.com/en-US/API/Runtime/Engine/Engine/ABrush/index.html

ANavMeshBoundsVolume inherits from ABrush

so you can access public/protected code

[static crater]

yeah

so basically i dont see any real possible way to like set the brush

it only has like GetBrushComponent()

however so it seems the brush is already created? should i swap it with a created brush in some way?

or i should setup the brush?

[manic karma]

you just need to set the brush settings

[celest python]

In gameplay debugger it looks like my Run Behaviour node is executing but my breakpoints inside of that BT doesnt execute, why this is happening?

This is not executing

[manic karma]

You gotta do some digging. Look through the brush component to try and find where the settings are stored

[static crater]

Yeah so it looks a little weird.. e.g. there's no such setter for Brush Type

its not even possible to select 'Brush Type Box' inside the editor

but well, first gonna see how brush works at all 😉 thanks for some advise

[manic karma]

I guarantee, if you can find where it is stored, you can figure out how to change it

[static crater]

well i actually see some posts from people trying to change the navmesh bounds at runtime using c++ or blueprint but they kinda struggle

and so, yeah i do add navmesh at runtime

[manic karma]

well are their struggles related to understanding the c++, or with the results of changing the values?

[static crater]

hhm, lol okay

[lyric flint]

@lyric flint thanks bro! saw it later cause I went to sleep! thats really helpfull 🙂

[static crater]

i think with updating a nav mesh bounds volume at runtime, may not work

[manic karma]

can't be the case

surely

you can force a rebuild of the navmesh at any time, so changing the size at runtime can't be a problem

[static crater]

actually yes, rebuilding navmesh works, but that does not tell anything about the NavmeshBoundsVolume

[manic karma]

tellin you it's gotta be in the brush somewhere

[torpid juniper]

How do blackboards work with subtrees a la Run Behavior Dynamic nodes?

Is it correct to assume there is no shared state between the parent and child, and that if this is something you need to do you could pass it back and forth via calls to the controller?

[misty wharf]

iirc subtrees use the parent's BB and that's it

[torpid juniper]

How does that work if the subtree is set up with a different blackboard with decorators expecting different values

[celest python]

Is it makes sense to run AI Move To in BTTask? Because its always failing with "aborted" flag

[torpid juniper]

it will fail with aborted if the task is aborted due to decorator logic in the tree

i think it will also abort if the location you're asking to go is not navigable

[celest python]

First posibbility makes sense then, I should keep digging into BT

Thanks

[torpid juniper]

You can look at the behavior tree during runtime to see where its at in the tree

[celest python]

I am watching the tree via gameplay debugger, it stuck on the same BTTask

Since Finish Execute is not getting called after Fail node of AI Move To

[torpid juniper]

Probably unable to navigate then. Try placing a cube where you're telling it to go and verify its actually on the navmesh

[celest python]

👍 Thanks, just realized I was trying to get a world location of a component that doesnt exists in the level

Its happening because of its not navigable

[torpid juniper]

👍

[pine steeple]

@torpid juniper you can create a parent BB for your normal BT, then your subtrees can use a child version of the BB

though this works, i have found issues, which is why i no longer do it.

[misty wharf]

It feels a bit tricky to make good use of the BB... at least to me it rapidly starts feeling like "a random assortment of values" :P

so instead I have a bunch of tasks which just query stuff from the pawn directly

[torpid juniper]

@pine steeple What do you mean a child version? Like an actual extension of the original BB? At a glance it does not look like the editor provides a way to extend BB classes. Are you also saying that the child instance would auto populate with the data of the parent?

I think I'm fine if they just don't share bb data at all, I was just curious. In general I feel like I'm struggling to grasp what data to put in a blackboard vs. keep in the controller. It feels like the answer is increasingly only things that directly driver the decorators. Anything else becomes quite cumbersome to setup the keys when I could just make a function call to the controller in the task directly.

[torpid juniper]

Yes that's more or less the conclusion I was typing out simultaneously haha. Although straight query tasks should probably be services I think?

[misty wharf]

Yeah it kinda depends on what you're doing

Most of my tasks don't look up values but some do, I also have a number of decorators which can check values directly on the pawn for conditional execution and such purposes

[torpid juniper]

hmm... for some reason I never thought to write a decorator. I've got services that just update bb state and affect the decorator based on that. Custom decorators probably make more sense if that logic is only relevant for that BT state...

[misty wharf]

No idea but at least it works for my use :D

[torpid juniper]

ugh, ai feels like the biggest slog in unreal.

[misty wharf]

I dunno, I find it pretty good

Try writing AI behaviors in C# in Unity no thx :P

[torpid juniper]

I started out in unity c#, but I never bothered to properly learn the tooling so it was all from scratch. Wasn't the best of times.

[deft sedge]

weird question, can a behavior tree service be event driven instead of on Tick?

The answer is yes, but what I'm more interested in is disabling ticking on the service.

[glossy spire]

you can change the interval

not sure if you can make it zero, but make it 100 or something should be good enough

[torpid juniper]

is ticking at all a concern if there's no implementation for the tick event...?

[glossy spire]

i dont think so

[deft sedge]

well that's fine then

I made a bind to ai perception so it will only fire when stuff moves in and out of that

[simple crest]

an empty blueprint tick is expensive as shit if you have a lot of them

[deft sedge]

hmm that's what I thought

[torpid juniper]

define a lot

[simple crest]

"results vary based on everything" but if you look around and crunch some math I think you'll conclude an empty BP tick node costs somewhere around 0.5 microseconds. remember the budget for 60 FPS is 16666 microseconds

[pine steeple]

i removed an empty BP tick node on actors (we had 1000 of them in the level) and it was costing .5ms of game time!

this is hardware dependant also

maybe 1ms on on someone elses spec PC

BPImplementableEvents will not be called if the node does not exist

[deft sedge]

won't it be called in c++ still

[pine steeple]

yeah but won't enter the VM iirc

and is cheaper

[lyric flint]

howd you set up a system where you can take control of the ai?

i have my AI set up to do basic tasks like gather food etc

[patent hornet]

you have all logic on how to perform actions in the pawn

you have all logic deciding which action to perform in the controller

that makes the PlayerController and AIController interchangeable

its just player input vs. behavior tree then

and you simply possess and AI

[lyric flint]

I mean, force them to do another task in the bht

[fresh remnant]

That BP Tick node was what I was trying to figure out trying to remove the other day..I don't even know how I ended up removing it...but eventually after a bunch of recompiling blueprints it dissappeared.

[lyric flint]

you wanna cast inside a bbtask?

[lyric flint]

do event recieve execute ai then?

oh wait

i always get casting confused 😛

you can cast to a bb

like this @lyric flint

[torpid juniper]

I've seen grace hopper's lecture many times on the importance of microseconds but honestly never found a case where it felt like it affected me. Guess that's changed.

For anyone who hasn't seen this wonderful bit of comp sci history https://www.youtube.com/watch?v=9eyFDBPk4Yw

[latent creek]

I think need to put all logic related to AI into services or tasks, changing variables of blackboard from other bluprints will not work (in my project it doest work).

[clever skiff]

to any people who have issue using paragon as an AI all you have to do is activate use acceleration in the character bp. that took me so long to find lol

that issue fix animation not playing correctly

[timber mortar]

i want to know something really basic. how do I add a 'function' or service to a behaviour tree that just checks if(boolKey == true)? so that it knows to continue the sequence?

[misty wharf]

There's a builtin decorator for it that you can use, blackboard condition or whatever it was called

[timber mortar]

now i'm trying to find out how i can set the blackboard value targetActor to a non-player actor that i have in the world outliner?

[timber mortar]

should i use a service, decorator, task, or some other means?

[glossy spire]

@timber mortar use a decorator

[storm zephyr]

hello, i have a nav mesh and i use level streaming to load levels that affect that nav mesh during gameplay. In the editor to get the navmesh correct i need to make sure all levels are visible in design time, if i don't then the navmesh won't work. The same thing happens in the packaged version but since i dont have design time then the nav mesh doesn't get created properly. any way to counter this and make sure the nav mesh is updated regardless?

[glossy spire]

I think you have to build the nav mesh while all the levels are visible in editor

then dont rebuild later

[fresh remnant]

@storm zephyr set your navmesh to Runtime Generation: dynamic

[fresh remnant]

Is the most efficient way to handle cooldown with behavior trees a simple wait node once a weapon fires? Decorators that check if cooldown down seem to get hit every tick otherwise and seems very inefficient.

[storm zephyr]

@fresh remnant does it have to be dynamic? right now i have dynamic with modifiers

[static crater]

Hi, is there any limit in size for the navmesh bounds volume?

(using nav invokers)

i created a nav mesh bounds volume of 8192x8192 meters, but nav invokers wont generate the navmesh anymore..

[static crater]

i managed to get it to work by changing 'Cell Height' to 20, any idea why it works then?

[timber mortar]

probably because you're making the lengths of each cube dimension less disproportionate to eachother so it can scale better

maybe shapes dimensions can only be so disproportionate

for some reason i cannot set the Marja variable here to the object shown in the dropdown, it's always None, any clues why?

[misty wharf]

because this is an asset and those are objects that will be spawned in the level

although they "exist" in the level in editor, they don't actually exist at all until the game starts and hence it's not possible to assign them into other assets

you will have to add some logic to assign it into the BB at runtime such as on Begin Play or some other event

[timber mortar]

thank you man

[uncut python]

hi everyoen i have a quick question, my AI was working perfectly fine the other day, even with crouds (IM using crowd controller). Suddenly today I open my project and the zombies dont respond at all, and my BT keeps stuttering like in the video. What could cause that?

i dont understand how it couldve suddenly stopped working

i didnt extend my nav mesh 😫 and i moved all my nodes around

[misty wharf]

the moveto doing that suggests that it's immediately failing

check if your navmesh is actually generated, I've had some cases where it just randomly disappears and requires you to manually rebuild it from the build menu

[uncut python]

Yes thank you

I made the noob mistake of assuming the AI work anywhere

but now all is well

I appreciuate it

[pallid atlas]

I didn't know that... I always just assumed that the navmesh was generated at runtime. good to know.

I suppose, duh... how else would it be present before PIE

[fresh remnant]

navmesh can be set to dynamically generate/regenerate during runtime, but creating the actor itself is done on build. You actually have to delete your navmesh actor from the level, and press build again if you modified navmesh settings through editor->properties because old data lingers sometimes, and can cause problems/bugs and even crashes

[fair zealot]

:triangular_flag_on_post: Aditya Raj#0050 received strike 2. As a result, they were muted for 1 hour.

[swift bolt]

Epic has some work to do https://youtu.be/nnuSQvoroJo

2:26 It's like having a human actor to direct in your game

[ocean delta]

anyone know of a BTDecorator in the UE source that's easy to understand? trying to create BTDecorator and having some challenge

actually the CheckGameplayTagsOnActor one is not half bad at all

[ocean delta]

is there a way to run something only when the BTService first starts?

i was missing bNotifyBecomeRelevant

so i'm trying to set a Vector in my blackboard but the value is always (Invalid). i'm doing it through CPP and i'm not really seeing why this is a problem

BlackboardComponent->SetValue<UBlackboardKeyType_Vector>(
                InitialLocationKey.GetSelectedKeyID(), EnemyUnit->GetActorLocation());

[ocean delta]

lol it's not getting set at all

sigh... the following block of code was missing from the service

void UBasicEnemyCombatBTService::InitializeFromAsset(UBehaviorTree& Asset)
{
    Super::InitializeFromAsset(Asset);

    UBlackboardData* BBAsset = GetBlackboardAsset();
    if (ensure(BBAsset))
    {
        InitialLocationKey.ResolveSelectedKey(*BBAsset);
    }
}

[lyric flint]

@swift bolt gpt3 is massively slow (needs to run on a cluster slow) and it only generates random texts that makes semi-sense

it doesn't have any overarching context

doesn't have any connection to the world etc

gpt3 is a language model by design.

[wet ether]

Does any of you know how to move higher the SIght AI Perception point? I want the enemy to see the head

[pine steeple]

@wet ether only doable in C++

[wet ether]

I assumed this option, but what exactly should I do? I have no even a single idea

[pine steeple]

you need to implement the IAISightTargetInterface interface on your players C++ class

and override virtual bool CanBeSeenFrom(const FVector& ObserverLocation, FVector& OutSeenLocation, int32& NumberOfLoSChecksPerformed, float& OutSightStrength, const AActor* IgnoreActor = nullptr, const bool* bWasVisible = nullptr, int32* UserData = nullptr) const

[wet ether]

wait. In my player? Im so dumb, i did that exact same thing in the AI character. Let me try that in my character and see if that works

[pine steeple]

right its on the player

Observer will be the AI

so you do like a trace from ObserverLocation to say Head, if it hits, then OutSeenLocation will be players head, and you return true

you can trace for all different body parts

[wet ether]

So, i've made a C++ Character class with overrided function and set it as a parent class of my player character. But the question is what is the body of the function?

[pine steeple]

so you do traces from ObserverLocation to parts of your player

and return true and the location of the hit part

bool AMyCharacter::CanBeSeenFrom(constFVector& ObserverLocation, FVector& OutSeenLocation, int32& NumberOfLoSChecksPerformed, float& OutSightStrength, constAActor* IgnoreActor) const
{
      const bool bHit = GetWorld()->LineTraceSingleByObjectType(HitResult, ObserverLocation, GetActorLocation()
        , FCollisionObjectQueryParams(ECC_TO_BITFIELD(ECC_WorldStatic) | ECC_TO_BITFIELD(ECC_WorldDynamic))
        , FCollisionQueryParams(NAME_AILineOfSight, true, IgnoreActor));
    
NumberOfLoSChecksPerformed++;

    if (bHit == false || (HitResult.Actor.IsValid() && HitResult.Actor.Get() == this))
    {
        OutSeenLocation = GetActorLocation();
        OutSightStrength = 1;
        return true;
    }

    const bool bHitSocket = GetWorld()->LineTraceSingleByObjectType(HitResult, ObserverLocation, GetMesh()->GetSocketLocation("head")
            , FCollisionObjectQueryParams(ECC_TO_BITFIELD(ECC_WorldStatic) | ECC_TO_BITFIELD(ECC_WorldDynamic))
            , FCollisionQueryParams(NAME_AILineOfSight, true, IgnoreActor));
       
 NumberOfLoSChecksPerformed++;


        if (bHitSocket == false || (HitResult.Actor.IsValid() && HitResult.Actor.Get == this)) 
      {
            OutSeenLocation = GetMesh()->GetSocketLocation("head");
            OutSightStrength = 1;
            return true;
        }

    OutSightStrength = 0;
    return false;
}```

@wet ether ^ something like this

[wet ether]

Thank you so much, i really hope that'll do the work

Seems like it doesn't recognize NAME_AILineOfSight and HitResult. What could be wrong?

I have just tested it and nothing has changed. Completely no difference. I am definitely doing something wrong

[pine steeple]

did you fix the code

[wet ether]

I've added this and the errors were gone

static const FName NAME_AILineOfSight = FName(TEXT("TestPawnLineOfSight"));

FHitResult HitResult;

[pine steeple]

thats correct

the first test will aim for the body

so if the pawn is not behind an obstacle

it will show the result in the center (like it was in your screenshot)

the second test will check for the head

so put your player behind a wall with just head exposed

and you will see it will be on the head

[wet ether]

Yea, i tried that, but here is what i got

[pine steeple]

do you have a head socket?

on that mesh?

ooh tell you what you could do if not,

[wet ether]

Any socket? Any special name?

[pine steeple]

  const FName NAME_AILineOfSight = FName(TEXT("TestPawnLineOfSight"));

    FHitResult HitResult;

    const bool bHit = GetWorld()->LineTraceSingleByObjectType(HitResult, ObserverLocation, GetPawnViewLocation()
        , FCollisionObjectQueryParams(ECC_TO_BITFIELD(ECC_WorldStatic) | ECC_TO_BITFIELD(ECC_WorldDynamic))
        , FCollisionQueryParams(NAME_AILineOfSight, true, IgnoreActor));
    
NumberOfLoSChecksPerformed++;

    if (bHit == false || (HitResult.Actor.IsValid() && HitResult.Actor.Get() == this))
    {
        OutSeenLocation = GetActorLocation();
        OutSightStrength = 1;
        return true;
    }

    OutSightStrength = 0;
    return false;
}```

do this

then you can modify /** Base eye height above collision center. */ UPROPERTY(EditAnywhere, BlueprintReadWrite, Category=Camera) float BaseEyeHeight;

on your character

to adjust the trace position

[wet ether]

So i rewrote the function and now this guy aims exactly at the character's head. And now everything works perfectly

Thank you so much for this. But why do i need to modify BaseEyeHeight?

[pine steeple]

did you use what i had up there ^

?

[wet ether]

Yes. I used this and now the enemy properly sees the character

[pine steeple]

the BaseEyeHeight is the position up from the capsule but if everything is working fine then leave it

but you can adjust that value to adjust the eye location

[wet ether]

i think i'll let it be

And yes. One more AI issue to fix

how to make an AI look at the same direction he is moving?

[wary ivy]

there's the orient rotation to movement setting in characters

[pine steeple]

well either that or control rotation

both work

Pathfinding will set the control rotation, and allows for Focus to be used (which you can't do with Orient to Movement)

[toxic obsidian]

Is there a way to make a decision tree option based on if a player's targeting reticle is aiming at (a la enderman being looked at)?

I want to make it so that if the enemy is targeted, it moves left or right to avoid the reticle

[lyric flint]

Absolutely! Use a line trace from the player, and broadcast to the target If the target matches whatever criteria. This way the target knows and act accordingly 🙂 You can also use TActorRange of your enemy type, to clear them if they are not the target anymore, so they don't have to run in circles like headless chicken 😄

[wet ether]

So i have a BT of my enemy character that shoots and focuses at a target

And now i want him to move to it's target while shooting and focusing so i did this

And now i want to add a delay to the Move To task so it will start shooting and then start moving in a few seconds later

So the question is how to do that?

[patent hornet]

funny thing about that, its stuck in that MoveTo until the move is completed

can't do anything else

[wet ether]

I thought that part of a tree would be enough. I have a movement interrupting task in another place

[pine steeple]

why you nesting simple paralleles?

[coral spire]

Hi, anyone knows why sense configuration is not inherited and recognized as change by each parameter but only as config itself?

Issue is that I have a kind of bigger hierarchy where I would like just change few parameters and still be able to change some others in the parent for all childs in hierarchy

[lyric flint]

Not sure, maybe I misunderstood your problem, but perhaps you should consider running RequestStimuliListenerUpdate on any component that changes parameters?

[coral spire]

This is a configuration issue, not runtime

when I change one value in child config, then it exist as separate config and wont inherit any new changes from parent in other values which I didnt touch in child

[vocal spindle]

Hello! Quick one,
for multiplayer, how can I cast a controller AI from its widget in BP without failing since it happens on server.
Or, at least, a way to read a variable that exists in the AI controller.
Thanks!

so this works standalone, but fails on server

or at least, to read a variable that lives in the controller

[torpid juniper]

Are you sure its the server where the problem is? That should be ok on the server. but the controllers dont exist on clients

[steel moon]

Hello. The trick question, is there an object that moves on the map, artificial intelligence needs to move inside this object while it is moving, is it adequate to use the dynamic nav mesh, or can you somehow bind the nav mesh to the actor so that there is no endless rebuild

[torpid juniper]

You don't want the navmesh to only contain the area around the followed object. You want the navmesh to cover the entire area, and then use logic on the ai controller to make it stay within the bounds of the followed object.

[wet ether]

The Shoot + Focus Parallel is required because i also have reloading logic in the Shoot task, and it takes some time to reload, and while reloading the enemy does not focus at his target so that's why there's a parallel

And MoveTo + Parallel is required because i want him to walk and shoot in one moment

This all works good enough but this way i can't add a delay to the MoveTo task

[cyan sigil]

Hello. I have two behavior trees, one where the AI will patrol and one where it will attack a stored target (set via Senses). What is the proper way to make a parent Behavior Tree that can swap between these two?

[rigid portal]

Is creating multiple behavior trees not best practice for the same enemy character ? Like a patrol enemy and a lookout enemy.

[patent hornet]

you have to create multiple BTs to have any complexity in AI behavior

there is a task RunBehaviorTree

so you compose the behavior from multiple BTs

[rigid portal]

Gotcha, thanks!

[pallid trout]

For a single AI, good way is to have states stored in an enum and switch between them according to some conditions.

[pallid trout]

The same works for you. Use a selector to run the behavior according to the state

[rigid portal]

For multiple that do different things, I use multiple bt

[pallid trout]

How many different things do you have

[rigid portal]

2-3

One guard patrolling, one in a guard tower, one drinking coffee

[pallid trout]

Thats pretty simple

[rigid portal]

When they see the player, they will chase till they loose sight, then go back to doing whatever they are assigned

I can assign an ID and have one BT do everything, but is the norm to do multiple Bt?

[pallid trout]

Only if its way too complex

[rigid portal]

I see. I'm not sure what the line is lol

What would be considered complex?

like taking cover during a firefight?

[pallid trout]

i made a simple one with patrol, investigate, follow, chase, find/take cover/find cover to reload, find health pickups etc . doable in one BT

[rigid portal]

I see. 😂 to me that seems complex

you wouldn't happen to have a vid of that would you?

[pallid trout]

No

[rigid portal]

When you say complex... do you mean computation complx?

[pallid trout]

No

Complex like spaghetti

[rigid portal]

where there a multiple options for an agent to do

or should I say, multiple decisions

[pallid trout]

If there was a single option it wouldn't be a tree😀
Just do what works for you.

[rigid portal]

Ahh true 😂

Thanks for the info, I really appreciate it.

[pallid trout]

Also multiple Bts need to be on the same blackboard to be changed at runtime

[rigid portal]

I can't have multiple blackboards?

Does the blackboard exist per instance of an agent?

[pallid trout]

I think no. Maybe if they're inherited

[pallid trout]

Yes

[rigid portal]

Ok cool

I'm watching the unreal Ai livestream....

It's god awful

Basic

[misty wharf]

Meh, I had the brilliant idea of using gameplay tags as results from my interaction menus, but of course blackboards don't support gameplay tag values... I guess it's back to using a regular old enum which is going to bloat like crazy with all the possible results :P

[patent hornet]

@misty wharf "blackboards don't support gameplay tag values" - try again 😄

and don't let @pine steeple hear you

(blackboards support names just fine, and tag is just a fancy FName)

[lyric flint]

Is anyone here good at making ai?

[patent hornet]

i would hope someone is

[lyric flint]

I am like horrible making ai with blueprints

[patent hornet]

@misty wharf you can also just casually toss an object with IGameplayTagAssetInterface into a BB

[misty wharf]

Interesting

I had a feeling the gameplay tags would be possible to translate into an FName or something

[patent hornet]

they are names

[misty wharf]

but it seemed less compatible than just having the gameplay tag option for the type

[patent hornet]

with a lot of fancy ontop

[misty wharf]

Right, good to know

[patent hornet]

FGameplayTag has one member and its an FName

so FGameplayTag::RequestGameplayTag(MyName) gives you a tag from name, and MyTag.GetTagName() does the reverse

both can also be done from BP, altho with slightly different syntax

[misty wharf]

Yeah looks like there's a Get Tag Name but I'm not seeing the reverse

I guess wrapping RequestGameplayTag would be pretty trivial though

[patent hornet]

yeah, we wrapped it 😄

[static crater]

So still trying to fix my navmesh for my procedural map

i wanted to see this setting works

however rebuilding navmesh at runtime does nothing

[misty wharf]

Looks like FGameplayTag::RequestGameplayTag is actually deprecated, should use UGameplayTagsManager::Get().RequestGameplayTag instead

[patent hornet]

locked on 4.25 so not for me

[pine steeple]

does not look deprecated for me in 4.26 either

its just a nice static wrapper for

{
    return UGameplayTagsManager::Get().RequestGameplayTag(TagName, ErrorIfNotFound);
}```

[misty wharf]

Wait which file is that in

[void stump]

any resource to look up for handleing lots of ai ~800+ repeating tasks like in age of empires chopping tree -> find station -> find nearest tree from last tree position and chop it

[misty wharf]

I think I was looking in the wrong file :P nevermind the deprecation

GameplayTagsModule::RequestGameplayTag was the one I was looking at

[low crow]

Hello!
I'm using behavior trees and I wonder if there is a way of passing variables as parameters value of tasks?

Example I want to modify the Acceptable Radius here and I wonder if there is a way instead of just duplicating this behavior tree

[misty wharf]

Afaik no, you have to build the BT tasks in such a way that they would accept parameters

You can make your own BT task for parametrized move which shouldn't be too hard to do

[low crow]

Okok I see 🙂

THanks!

[torpid juniper]

@void stump Nothing especially unique about what you're describing. A general look into how behavior trees should be fine for what you want.

[void stump]

are there no performance limitations ?

maybe some good workarounds?

what about flowfields and collision avoidance between ai workers

[pallid trout]

800 ai's wont be on the screen at once.

[void stump]

if 4 players each get 200 ai and ~100 are workers its possible that 400 but even 600+ be on the screen at once

and even if they are not visible it still needs to process it depending on the range between sawmill and tree time of transports differs and makes a diffrence

[vast relic]

For something like that you're going to definitely want an AI setup that is not evaluating every single frame for every single AI.I would try it with stock behavior trees first though, and just see how it does.

[pallid trout]

Disabling physics and options like tick only when render could be useful

Recent Ue livestream on crowd optimization with niagara could be exactly what you want

[torpid juniper]

Everything has a cost, but I don't think 800 ai should be impossible to handle so long as your setup makes sense. When I imagine the AoE II AI, it feels very intuitive. Avoiding evaluating something every frame is probably not a difficult barrier to overcome.

default crowd avoidance pathing should be fine.

[pine steeple]

@void stump what you can do is the ai offscreen, you reduce there tickrates of CMC, Skeletal Mesh, etc

we managed to bring 200 AI from around 3ms down to about .75ms by doing so

plus other optimizations (disabling overlap checks, etc)

so 600-800 is doable with some extreme optimizing, but on screen at one time, will be quite tough

but maybe the further the camera is away from them, they can just start reducing there tick times/skeletal updates?

so they look ok from far

[cerulean coyote]

hey guys im trying to have my enemy choose from a set of attacks. Each one should have a % to choose from, any idea how i could implement that?
for example the enemy would have a 35% chance to do attack 1, 15% chance to do attack 2, etc.

[misty wharf]

Generate number between 0.0 and 1.0, if number is <= .35, attack 1, else if number is <= .50 attack 2, elseif etc.

at least if the total % is 100 that'd work

there's probably some other ways to choose for example given an array that has a weight and value for each item, you can do some algo to pick based on that

google for "weighted random from array" or something like that and you'll probably find the relevant formulas

[cerulean coyote]

very helpful thanks @misty wharf

[sick locust]

just a quick question. is there anyway I can get this pawn to move specifically only on the X axis? it seems even when I do this it still rotates off into another axis..

[sick locust]

:D I fixed it don't mind me I have the iq of a crustacean

[torpid juniper]

Luckily I can think of no better animal to embody than a crab if your goal is to move along a single axis.

[lone cloud]

Hey there guys, could anybody help with this thing I have?

If you've every played Hitman or Assassin's Creed or anything, your probably familiar with the neutral/searching/hostile mechanic where it updates your HUD accordingly. I managed to create it myself, however not in the most efficient way.

Does anyone know the most efficient way that I could update it? I already fixed it and stuff so the code is working, just when and how should I do the code so it's efficient and doesn't eat away at performance

What I have is whenever the ai goes into a new branch in behaviour tree (hostile/searching/patrolling) it loops through all the other ai to see their states and then it chooses the final outcome (if one AI is hostile and one AI is patrolling, I wanna make the HUD show hostile)

The problem with this is that EVERY AI loops through EVERY AI and that's just way too much on performance

I have some ideas for fix, but I wanted to ask and see if anyone knew the optimal way to do this!

[patent hornet]

AIManager

that is statically accessible (1 actor on the level or 1 component on a "singleton" actor)

that keeps that info ready for the AI to access

everything that is of interest to AIManager registers with it on BeginPlay, and unregisters when it does @lone cloud

as it knows the position of everything of interest at all times, you no longer need to do overlaps or similar expensive checks, just disaancesquared

[lone cloud]

Oh that's cool

I've never used an AIManager before

@patent hornet , the way I did it was with a function on the game instance that searches for actors of that class and loops through them

So this is all unnecessary you mean?

[patent hornet]

All Ai register with AIManager

no need to loop through every actor on the level to find AI

they are already sitting in an array there

[lone cloud]

How can I find it?

[pallid trout]

I havent heard of this before. Cant find any documentation😕

[pallid trout]

If an AI is hostile, you can get the player pawn and change the HUD state from the AI tree itself maybe

Instead of getting all AIs you would be getting the player from all AIs individually

[lone cloud]

The issue with that is that they will overlap... Meaning that the patrol will cancel the hostile, and the searching and so on

If the player is hostile, it should overlap anything else

[pallid trout]

Then storing their references in an array is the best bet

Im curious how this can be done with "ai manager". maybe its c++ only

[patent hornet]

@pallid trout the AIManager is just a practical way to call the custom class

in practice it combines the elements of singleton, observer and mediator patterns as needed for your game

[lone cloud]

And then using tick to check changes?

[lone cloud]

Btw, I could find any docs about AIManager. If you could provide me a link to what you mean or describe it with an example, I would appreciate it.

[pallid trout]

you can store the previous state and the current state. Also an integer for the number of hostile AIs in the gamemode or level bp or game state. each interval (sec or tick), check if the state is hostile.if the previous state was not hostile then +1 else if the current state if not hostile and the previous was hostile then -1. You could easily get how many hostile ais there are

could work for all states with a bit of implementation

[lone cloud]

Hmm

As I said, I already have the system working but it's not efficient, that's it.

Do you think doing it every tick would be more efficient?

[pallid trout]

Its not using get all actors of class

[pallid trout]

So yes its definitely a lot more efficient

[lone cloud]

So it's get all actors of class that's really expensive I get?

[pallid trout]

Yes

Do it once and store all in an array, use ai manager or use the workaround i said above. Theres tons of ways

[lone cloud]

Hmm

I see

But what would happen if I did it at the beginning but then after the AI dies and the controller is destroyed, would it become a nullptr

[pallid trout]

Yes

[lone cloud]

Thats what I was afraid

[pallid trout]

A simple is valid check will fix that

[lone cloud]

Hmm

I'll have to check on it tomorrow, rn I'm on my phone

Thnx for the advice

[sick locust]

anyone able to shoot me in the right direction for making fairly basic ai for a 2D platformer? I can't seem to get mine to work even with a navmesh

[lyric flint]

YouTube 🙂

https://www.youtube.com/watch?v=D_XDwBpSgPU&list=PLKMRiZuSgt-7wY7hfUzg8JcuTFXAf85jv&index=9

[lone cloud]

I haven't done that before, but I'm sure it would have more variety and taste when you split each BTs that way different enemies act differently.

Also you might be handcuffed if you stick to using only one (i.e. if you decide you want the ranged attack enemy to run away when the player gets close, it will be more difficult when it's mixed with other enemy code)

[pallid trout]

definitely separate bt's and controllers. separate bb's, might as well

[lyric flint]

Separate blackboard is not needed, because it is conceptually the same regardless of attack type, and the AI gets its own instance, done properly. Separate behavior trees, no problem, I guess, at least for keeping it clear and clean 😄

[lyric flint]

Question: What does the near clipping radius do?

[unborn jungle]

Do AI Controllers automatically get destroyed when the pawn that they are posessing does?

I don't see any destroy calls happening for my AI Controllers but they no longer appear in the outliner when the pawn they possess get unpossessed and destroyed

[pallid trout]

They get destroyed when everything referencing them gets destroyed

[manic karma]

any idea how can I fix stuff like this on my nav mesh?

Enemies are getting stuck at the bottom of the stairs

seems to be they can't bridge that gap

[pallid trout]

In project settings try increasing the height of the nav mesh

[pallid trout]

is your character smaller than the mannequin

[manic karma]

you mean the cell height?

yeah the character is smaller

quite small actually

[manic karma]

sorry ^

[pallid trout]

thats probably why youre facing this issue. Either the cell height for the nav mesh or step height in your character works

[manic karma]

I've got the cell height at 10 and the max step height at 36 in the recast

the generation near the stairs is so odd

[pallid trout]

No matter the generation. is it functional

[manic karma]

Nope

they get stuck at like the middle of the stair base

but at the sides they can get up

It's really weird

the whole map is producing areas where the AI get stuck

on corners

invisible objects

trying to path directly to the character instead of on the navmesh

[lyric flint]

So is navmesh UE's ONLY source to have ai work?

[manic karma]

keep forgetting to reply you sorry

[coarse obsidian]

@lyric flint Actually no, you could completely design AI without navmesh, blackboards and behaviour trees...

just by making rules in blueprints / cpp just like you would program anything else...

[timber mortar]

hey guys. i'm wondering if i could set a Blackboard variable (bool) spookedKey as a pointer to a corresponding isSpooked bool from the AI Controller's 'Pawn' class?
otherwise i'll just have to get the variable every tick.

[misty wharf]

@timber mortar no. The better solution would be to have an event dispatcher in your pawn like "OnSpookedStateChanged" which gets triggered when the spooked value is updated, you can then listen to the event in the controller to update the BB

[cyan sigil]

Hello, AI. I have several characters being put on the same location and asked to path to different locations. I am finding that this is unreliable, and they will often path to undesired locations or attempt to walk off the map. Is there a way to prevent this bug? Alternatively, is there an easy way for me to place them so they do not overlap but are as close to the spawn point as possible?

[fresh remnant]

@cyan sigil you can either do collision for each pawn which will keep them separate, or use crowd navigation(detour crowd)

[cyan sigil]

How would collision help me? The current algorithm is looping over each character and setting their location to the spawn point.

[fresh remnant]

physics will also push them off the navmesh if you spawn them all in the same location, but they should path back soon after, you need invisible collision walls to keep them from walking off the map

collision would have them spread apart once you do spawn them

the better way to do it is NOT to spawn them on top of each other

because that isn't supposed to ever be a good state for AI

[cyan sigil]

Yeah, that's the other part. What's an algorithm to spread them out? Do I have to use EQS?

[fresh remnant]

spiral

spiral + sweep collision traces

[cyan sigil]

Can you link me an example? I don't have spiral math memorized.

[fresh remnant]

you do a sweep around a spiral on a location

and see if there's a collision

if not then pop it down

use the capsule of the pawn to sweep, not a line trace, so you get accurate placement of where you can plop it down

you're in luck, I have that handy:
// from https://stackoverflow.com/questions/13894715/draw-equidistant-points-on-a-spiral

scroll down for the equidistant one, works best

[cyan sigil]

Does this assume open space? The spawn point might be in a hallway

EQS it is!

[fresh remnant]

that's why you do the trace

[cyan sigil]

Will do

[fresh remnant]

you test each point, if it doesn't work go to the next point

[pallid trout]

tinkering with navmesh settings worked for me a while back. if its still not for you then I dunno

[manic karma]

yeah I've spent hours messing around and not really gotten anyway

[cyan sigil]

@fresh remnant Thanks, spiral worked great, though it turns out it was also an issue with the MoveTo node I was using (unique to my team)

[cyan sigil]

Another AI question. I've set up my parent BT (though I wish I didn't have to make my own node for assigning the dynamic sub BTs). They currently branch like so:

However, the Idle includes a 5 second wait inside it, so even if Enemy is set, the wait needs to expire before the branch changes.

How do I have the tree re-evaluate when the value Enemy changes?

[cerulean coyote]

Try messing with the "observer aborts" here, it will notify the observer based on a change in value or result (you can choose) and then depending on what you pick it will "abort" the node, and start the sequence again once it senses a change @cyan sigil

[cyan sigil]

And that can be configured on the Decorator?

Do I need to put the decorator on the Idle node then?

[cerulean coyote]

yeah you can put it on the idle node as well. If you want, you can just attach them both to a sequence and have the decorator on that, and it will apply to both of them

[cyan sigil]

Ah, so whenever it flops it will go back to the sequence

[fallow hound]

Anyone ever seen a bt just get stuck in a branch? Looking at the bt it gets stuck in the first node of the branch regardless of which node I put there. The bt is still ticking. The branch has a decorator which should have aborted the branch but it's just running the first node task. This happens on the bt start maybe like 10 percent of the time.

[fresh remnant]

Anything out there to automatically allow units to jump between navmesh regions that are not connected but are a certain 'jumpable' distance apart? I would like it so that whenever the navmesh is regenerated, maybe a new platform is built, that these new areas are 'jumpable' from the current nav mesh for certain units when doing pathfinding

[lyric flint]

maybe https://docs.unrealengine.com/en-US/Resources/ContentExamples/NavMesh/1_2/index.html ? Although Rama has a different opinion 😄 https://forums.unrealengine.com/development-discussion/c-gameplay-programming/3681-navlink-and-making-ai-jump?p=222996#post222996

[fresh remnant]

Yeah I don't like nav link proxies they are very limited

I'll take a look at what Rama did, looks like the right direction to go here.

thanks for the links! @lyric flint

[timber mortar]

how does one get the Pawn or AI Controller from within a Behavior tree (task/service/decor)?

nevermind

[pallid trout]

is there a way i can filter out some specific pawns (like the ones who are dead) from eqs?

In the first part Im destroying the pawn after death and it works fine

[misty wharf]

you would have to write a custom EQS test for it I think which would check the dead state from the pawn

[pallid trout]

custom eqs test? is that even possible.

ive done this with the context inputs but never this

[misty wharf]

it is, but only in C++

[bold crest]

Whats a good way to have an AI "perceive" actors that damage the AI? I want the AI to chase after the player if they get hit by a player projectile, even if the player is out of sight

[pine steeple]

Perception Component and Report Damage Event

[bold crest]

thank you!

[silent remnant]

Is there a function for getting the nearest navigable/reachable point?

not a random point within radius, but the closest navigable point to a location

I found ProjectPointToNavigation which has query extent if anyone else is trying to find this

[exotic veldt]

is it possible to make 2 nav meshes for instance one for cops and one for npc's?

[tall rock]

Easiest way to have a BTTask that activates a GAS ability wait for the ability to call EndAbility?

[misty wharf]

Not really familiar with GAS but in general the way you can do those types of things is to bind some event listener which gets called when the action is complete, and have it call Finish Execute only then

I'd imagine there's some way you could get notified of the ability finishing

[tall rock]

Hmm yeah I'm trying to find that notifier, maybe i'll ask in the gas chat

[weary zodiac]

Anyone see anything out of the ordinary with my Behavior Tree?

and then AIController

For some reason that I don't understand the behavior tree doesn't get entered and ran.

I have the BT set on my Enemy AI BP and I have followed code execution to the call to this->RunBehaviorTree(MainTree) but I don't see the BT run.

That's what I see when I PIE, but now execution flow. I am pretty new to behaviors, so there's also that.

Not sure if "STEPS BACK -1" is indicative of anything related.

Thanks in advance for even looking at my question.

[weary zodiac]

ugh, solved... I forgot to call Super::BeginPlay() in my AIController override function

[cyan sigil]

I'm having issue with a custom decorator.

This breakpoint is never being hit, even though when I inspect the unit I can see that the correct blackboard key is filled.

oh! My mistake. I am getting blackboard value by name, not the current key.

[fresh remnant]

Yes, you can, there are a few things you have to do if you're using something crowd following, for it to work with both navmeshes. But for non-crowd following, I think the best way is to create two derived classes from ARecastNavMesh and setting the cop agent to use one of the derived classes, and the enemy to use the other. You want to make different ones for different agent radiuses usually. Then you set your agent to 'prefer' the specific derived Recast mesh class in the Agent Properties. Unreal's way of trying to figure out which navmesh to use for which actual agent is messy.

[nova prawn]

Hi, Is it possible for a child tree to run a parent tree? The child has a Run Behaviour node requesting to run the parent tree? Is this possible ? or are all trees individual?

I was h oping to run "common" tasks in the parent such as Idle, Wander and things like that and have specific tasks in the child tree

[patent hornet]

you can use run behavior tree task

i don't see why BT would bother even having a concept of "parent" tree

so i doubt there is anything to prevent you from doing it

the maintenance might get ugly though

[nova prawn]

So would I do better to have one tree with a bunch of sequences with decorators basically doing a Select on UnitType?

[patent hornet]

that would entirely depend on what you're doing

[nova prawn]

Coz I have Harvesters, Workers, MilitantUnit,

[patent hornet]

and they can run their own "root BT" each

reusing common tasks with run BT node

tasks, as in BTs

all 3 of those units will have more or less same logic for roaming around, eating, sleeping, or whatnot

you encapsulate those in BTs

and they run it from their "root BT", which you have one of for each unit type

[nova prawn]

This is what I have atm for a Harvester

It runs into the default state.

Parent

This tree never gets executed.

[patent hornet]

that does need FinishExecute in that task

if you ever want it to exit from that Print

[nova prawn]

or would this be a better idea in the parent tree?

obviously linking up the other nodes lol i forgot to do it before taking the snippet .

It never gets into the PrintUnitState.

[patent hornet]

that has a tendency to cause too much mess later on

so best avoided from the start

[nova prawn]

Thats what I thought which is why i was trying to get the parent tree to run.

[patent hornet]

BTs don't scale too great, so anything over 40-50 nodes is unmanageable

and you're inviting the massive BT situation with that last example

[nova prawn]

Question do I need to add Run Behaviour Tree to the Parent AI atm I only have Run Behaviour Tree in the Child.

[patent hornet]

define parent AI

[nova prawn]

This is the child AI

Parent has no AI tree connected.

[patent hornet]

the last screen you posted would require only the AI superclass to run BT

[nova prawn]

I thought the Run Behaviour Tree node would automatically run the Parent Tree once it hit the Run Beahviour Node.

[patent hornet]

anything else would require only subclasses

also

don't run BT from BeginPlay

as controller doesn't have a pawn possessed yet

[nova prawn]

Oh ok didnt know that only recently got into this, So still learning a lot. xD

[patent hornet]

when you spawn AI its usually

Spawn Pawn, Pawn calls BeginPlay, Spawn Controller, Controller calls BeginPlay, then COntroller possessed the Pawn

[nova prawn]

Is that the same for a Character class?

[patent hornet]

both BeginPlays already executed, but you do have OnPossessed or some such

yes, Character is a Pawn

[nova prawn]

Ok

[patent hornet]

there are a few exceptions to this, but for now, best run the BT from EventPossess

[nova prawn]

So this would be better ?

Ok I got that to still run into the default.

Never lights up.

[patent hornet]

show me the print task

[nova prawn]

I just found out what it is.. Seems weird but here goes.

Does run when it shares the same blackboard I get message "Hello from ParentTree" show up