gameplay-ai

[sudden citrus]

Imagine a stress testing AI which is supposed to run multiple branches in a loop, without any regard to how it looks or whether it makes sense. If one fails, you'd still want the loop to proceed because you're just testing stuff. It lets you reuse nodes in different scenarios without having to make wrappers.

The real cursed thing I've seen is a "return false" node used in a selector... used to loop while polling a bool in the blackboard

[gray sail]

How is dynamic AI navigation handled in large open worlds?
Let's say e. g. an NPC should go from Town 1 to Town 4. How would they find the correct path there?
In a small world, a simple pathfinding algorithm would just be ran on the navmesh, but in large open worlds (e. g. Skyrim) with complex road systems, this isn't really performance-efficient if many NPCs would be doing this, right?
And if it is actually an usual navmesh, I assume the resolution is extremely low to decrease the number of nodes?
Bonus question: How are navmeshes set up with paths through landscapes that the AI should not usually enter? Manually thousands of volumes seems extremely tedious to me, so does this work in a different way (or are the volumes included in e. g. a road spline actor)?

[sudden citrus]

To answer your first question: hierarchical pathfinding, or road networks, are usually the solution

[misty wharf]

Yeah it just seems a Force Success decorator does the same job, and is more clear about how it's intended to be used :D

[sudden citrus]

Second question: you could automate placement of areas around certain obstacles, change the nav agent size (if you don't want them going in between trees) or mark up with volumes automatically. The solution depends on your exact use case

[sudden citrus]

Oh sorry I thought we were talking about the decorator in the first place

[misty wharf]

Yeah I meant the Finish With Result node :)

Just can't think a lot of usecases for it where it would make more sense over Force Success

so wondering if I'm missing something about it :P

[celest python]

None of the NPCs in Skyrim move to Town1 to Town2 though

If you encounter one of them in the wilderness they just move to a random location in their way

Usually you want to do the same

[gray sail]

Thanks, hierarchical pathfinding seems interesting.
I did a couple of google searches, but couldn't really find much on it in the context of Unreal though. Do implementations of this or something similar exist for UE, or would you have to implement such an algorithm yourself?

[gray sail]

Don't some NPCs travel in the context of quests? I'm not too sure though - it was only an example anyway.

[celest python]

If they do, they probably follow some cluster of navigation paths I guess

[celest python]

It exists

Not sure if its exposed to BPs

[gray sail]

Are there any documentations or tutorials on it? Didn't see any.

[sudden citrus]

It's not implemented. The function call routes back to basic pathfinding

[celest python]

Oh really? Damn

I thought I saw it somewhere

[celest python]

AI framework is completely undocumented

[sudden citrus]

The interface exists, it's just a ruse lol. You can test reachability using the cluster graph though, by setting the mode on Path Exists decorator to Hierarchical

[celest python]

Ah yes that was what I saw

Welp, looks like Fortnite never needed it

[sudden citrus]

Yeah, they seem to just build large paths from known waypoints, because FMetaNavPath received updates from the fortnite branch.

When asked on UDN, Mieszko said they won't implement hierarchical search because the cost of maintaining a hierarchical graph in dynamic generation eats up all the savings from searches - which kind of misses the point because you hit the expansion limit no matter the time

https://webdocs.cs.ualberta.ca/~nathanst/papers/mmabstraction.pdf

you can implement this

(but it assumes uniform costs)

I don't know what the paper's licence is, similar to this which seems to be an iteration: https://webdocs.cs.ualberta.ca/~nathanst/papers/sturtevant2019dwa.pdf

[celest python]

Kinda way too low-level things for me, but I like studying these type of papers. Thanks for sharing

[sudden citrus]

Also FMetaNavPath is a great way to actually build hierarchical paths using the above approaches - you just give it the top level path and it will kick off low level searches when reaching points, or you can override that behaviour to do granular searches 2 waypoints ahead to smooth it out (because the hierarchical path will be blocky and wasteful)

It's not a terribly difficult thing to make once you know how to talk to the navmesh 🙂 it maps to recast concepts pretty well.

[gray sail]

On another note:
Let's say I have a path going through my level, with some surrounding area (using dynamic navmesh generation with invokers).
I want AI to only have this path available as navigation area, unless they are explicitly allowed to use another one, e. g. when they are in combat or a different AI category like a wild animal.
My current idea is to use have modifiers added to the path spline apply custom areas and override their cost settings by using Navigation Query Filters on per-AI basis.
Some AIs would use a filter on their operations that overrides wilderness costs to be extremely high, and for others the opposite. When they e. g. enter combat, this filter could also simply not be applied, and they would be able to use all of the area.
I don't know if all important functions support filters, so this could be a flaw.
Is if this is a good concept, or if there is a better way to do this (also regarding performance)?

[ocean wren]

Might be worth watching how they did the navigation for that Hideo Kojima game (I'm blanking on the name, but I recall a GDC video on the navigation)

Death Stranding!

Oh to be a fly on the wall in Epic code design meetings..

So far reading the Mass.... framework, it looks to be an ECS system based on "fragments" which are essentially components in the ECS and there's a command buffer which adds/removes them from "entities", which I assume are actor base classes with some container for holding fragments

There's also the concept of tags in there.. so I guess some sort of tag based filter mechanism

There's a concept of a "processor", which I assume is the base class for whatever takes a group of entities and does some computation on them

There's also a "phase", which seems to determine the ordering of the processing

Hmm, so there's a UMassSchematic derived from UDataAsset that defines the processors array. I don't know if those are user editable or not

Man this stuff is going to freak people out 🙂

So the basic idea, is that you have a data driven ECS system a bit like Unity's DOTS, based off of stuff that you can read about by Scott Bilas from Gas Powered Games back at GDC 2010-ish

The components are called fragments, presumably not to confuse people used to ActorComponent, so of course that becomes more confusing 🙂

There's a notion of an archetype, which is basically a template for fragments + tags to add to an entitiy... so think of it as a system that allows you to clone the fragments and tags of another entity (bit like a Unity prefab)

and of course, this will all be completely undocumented 🙂

Toying with the idea of giving this to my students to document 🙂

[ocean wren]

That would be too cruel though

[celest python]

Have some mercy, please 😅

[celest python]

My "wtf" moment was when I saw they made the replication similar to Source Engine's system, like
#if CLIENT_DLL thing

[celest python]

And yeah, afaik it is editable

[ocean wren]

I'm looking for something useful for my advanced graphics MSc students to get their teeth into

has to be something graphical but slow, easily understandable but reasonably easy to improve performance of

I'm thinking some kind of skeletal animation thing

Hmm, so the new smart objects are pretty simple.. a new component type and a few nodes for the BT (findandusesmartobject)

[misty wharf]

smart objects?

[ocean wren]

Yeah, smart objects 🙂 they're a sort of coordination for multi-agent use

generally popularized by the sims

I've used a similar approach before to get a squad of soldiers to clear a room of threats by going through a door in squad order etc.

You can imagine one being used for moving the bomb in TF2, they had a similar thing in Wolfenstien (RoTCW) for moving the train using the AI

basically a "slot" system object that coordinates who goes where

They used smart objects to annotate the beach scene in Bioshock Infinite, good GDC talk about that on YT

They'd be useful for some of the "queing at a till" situations people have been asking about around here for example

[misty wharf]

Yeah I have a vague idea of how it works but is this now builtin or what were you referring by "the new" lol

I think I actually have a smart object of sorts in my queueing system, but never really thought of it being particularly smart lol

[ocean wren]

Yeah, they've added it into UE5

along with the Mass Gameplay thing

and the StateTree system

[misty wharf]

interesting

I heard about some of the AI things in it but didn't know about this one

[celest python]

Did you saw Instanced Structs?

Its probably only made for StateTree 😄

AI behaviors encapsulated into structs

[ocean wren]

Yeah, I had a quick look at the StateTree stuff too

[sudden citrus]

Really useful to read about others' discoveries in 5.0, I'm still due a deep dive into Mass

[sudden citrus]

All important functions support filters and you can also forbid certain area types (...which in code actually gives them FLT_MAX cost lol)

[hallow drift]

how can I make a pawn follow their path exactly the same as if it were to follow a spline? no more getting stuck into some anything

just follow the path as a spline

[sudden citrus]

what are you getting stuck into?

[celest python]

You can place nav modifiers to level to try to keep them in specific places while navigating

Like placing modifiers that costs more to move to edges of the roads etc.

[static crystal]

I'm trying to create a grid of points that are near actors with a certain tag

will the "GameplayTags" test here check the actors found in "Overlap: Sphere"?

and if not is there a way to do this out of the box, or should I just make a custom "overlap and contains tag" test

[misty wharf]

the tests are ran against the results from the generator

the overlap test therefore isn't really returning anything, it's just for testing whether an overlap exists

[sudden citrus]

Let's make sure we understand correctly, you want to:

• find all actors with a tag
• generate points near them?

[static crystal]

yeah kind of. Basically my actor needs to walk up to a piece of furniture and throw it at the player.

So the actor needs to find positions that are next to furniture and can also see the player from

[sudden citrus]

What you're doing in the screenshot is:

• generate a grid of points around the actor sending the query
• overlap with a sphere around each of the points around that actor, looking for furniture
• check that furniture for gameplay tags

[static crystal]

oh so it doesnt check the furniture that the overlaps find?

does*

[sudden citrus]

It does, but you're finding furniture that surrounds the points that surround a single actor

read both again carefully

[misty wharf]

I guess you'd want to first generate a set of reachable furniture within desired distance, then generate points around them

[static crystal]

so will the items returned in this case be the positions next to the furniture, or the furniture themselves?

[static crystal]

yeah

[sudden citrus]

Your current query will return positions of furniture that's near the querier, and it will be searching for them in a really weird way

Looks like you've just misunderstood how an EQS query is constructed, so:

1. a generator creates a lot of points using contexts - a context can be one actor or multiple actors

2. you can run tests against those point, filter, score them

Generators give you the pool to pick from, Contexts are reference points, Tests are how you pick them.

Do you want to find all furniture in the world or nearby furniture?

[static crystal]

just nearby

[sudden citrus]

There is no obvious way to do this so I see how you got confused

Basically you want to filter the context, not the points

is this a single player game?

[static crystal]

its multiplayer

so running the gameplaytags test against a grid generator does nothing right? because its just a set of positions

but would work agains the actors of class generator

[sudden citrus]

You can create a new Blueprint Env Query Context that generates furniture around the Querier

[hallow drift]

Doesnt matter what, it is just annoying that ai pawns even need collision while navigating

[sudden citrus]

It does matter because if you have more than 1 in a narrow passage, it's a problem that needs solving. You can also disable their collision

Do they get stuck in scenery or other pawns?

[hallow drift]

No, i dont even know what it gets them stuck

[sudden citrus]

@static crystal

[hallow drift]

There is nothing with collision there

[sudden citrus]

So there are no other pawns, they just stop walking?

[hallow drift]

They walk in place

And stop, that is a fail

But there is nothing to block them there

[sudden citrus]

Have you checked the navmesh in your level?

[hallow drift]

Yes

[sudden citrus]

how are you telling them to move

[hallow drift]

MoveTo(actor) in c++

And it works

But it has some spots it get stuck

[sudden citrus]

in what class is that MoveTo cause there's a bunch

[hallow drift]

Controller

[sudden citrus]

see you should have said that in the first place, I thought for a second they never start walking correctly

do you call the MoveTo every frame or just once?

[hallow drift]

Once

what is even stranger is that they can get there, but cant leave

In my engine pathing generated a spline and then objects followed it with no collision, and it worked fine in the big part, can't I emulate that in ue4?

[sudden citrus]

If you've done that before, you can make your own PathFollowingComponent that does that, sure

but I'm not sure if it will solve your problem

[dark warren]

Hi,

I try to get my head around Behaviour Trees but my Decorators just wont work (check the screenshot). Only the left part of the tree is executed even if the decorator returns false. Even inverting the value does not change anything. Why?

[misty wharf]

If TestDecorator returns false it aborts the entire branch it's on

Since your root node is a Selector, it will execute branches until one of them succeeds

so if your leftmost branch always succeeds, then the rest of the tree will never get executed

also note that it says your decorator on the selector is going to get ignored entirely unless you are running this in a sub tree

[dark warren]

Ok so how would I set up something like this?

[misty wharf]

so you first want it to run the patrol part, and once that succeeds, you want it to run whatever is to the right of it?

[dark warren]

got it. Placed the decorator (Has Waypoint) to the patrol sequence

[misty wharf]

Yep that should work :)

[dark warren]

Once I wrote the question I got it almost instantly 😄

[misty wharf]

yeah that's how it goes sometimes

[dark warren]

thanks!

[sudden citrus]

rubber duck debugging ftw

[dark warren]

Oh one other question. Is there a way to run a different behaviour tree (different file) within a behaviour tree?

[sudden citrus]

yes, see the Run Behaviour node

[dark warren]

I had this AI for several years running as a state machine and it's quite complex. Want to transistion to BT now for UE5

Perfect!

[sudden citrus]

Run Behaviour Dynamic lets you dynamically reassign the subtree but if you just want to statically split a BT, use Run Behavior

you can also tell the AI controller to run a different tree during gameplay, that kind of approach works very well with utility AI logic

High complexity in BTs should be avoided imo, it's a quick way to create something cursed

Or you can run a state machine that has a different BT in each state.

the only problem is that if you use different blackboard classes for each, they will be wiped

[dark warren]

Ok I plan would be to have the Patrol and non combat part in one BT and the combat in another BT. I should be able to apply a decorator onto a Run Behaviour node right?

On and how important is a Blackboard? I can't imagine that much use cases for my AI at all. I would use it for some condition but mostly the values would be stored in the AI it self and called from the Task and decorator nodes directly.

[sudden citrus]

The blackboard lets you decouple logic between your controller and other stuff, and the BT

Avoiding dependencies is a Good Thing

[dark warren]

but how is the blackboard directly avoiding it? If I need the focus target of the AI, I can call it directly from the AI instead of writing it to the blackboard and then getting the value from the Blackboard

[misty wharf]

Sometimes it makes sense to use it but others not... I've found using tasks and decorators to access the pawn directly works pretty well, especially if you have a lot of values to deal with because the blackboard can become very messy

Plus you'd need a lot of extra logic to move values between the blackboard and the pawn/controller

[sudden citrus]

That is the problem with huge BTs, the BB becomes messy.

[misty wharf]

Yeah, the BB editor is not great, you can't even reorder values

[dark warren]

I'll brobably mix BT and State Machine and avoid BB for the most part and hope it will work out

[sudden citrus]

If the pawn writes to the blackboard, and the BT reads from the blackboard, they don't know about each other, they're just accessing data by keys

If you do that, use interfaces

you don't want to discover later that if you open the BT editor it has to load a 9GB character

[dark warren]

I actually also do not use interfaces that much in the past as I always have a base AI class all the others parented from

[sudden citrus]

Let me put it this way: a lot of patterns are available that don't really matter in small projects but introduce good practices.

[dark warren]

I'm actually in bigger projects (consoles)

[misty wharf]

base character can avoid the "load 9GB char" issue as well assuming you don't hook up assets into the base

[sudden citrus]

Like, if you write hello world in C++, you probably don't care about heap allocations. If you write it 10k times you do

[sudden citrus]

I've seen a GOTY candidate ship with that problem 😄

[misty wharf]

hey if you got a PC good enough to work in the editor with that then does it actually make any real difference? lol

[dark warren]

I'm cheching verly basic conditions in Decorators right now. Like this where I check if the AI is able to wark around freely in a radius

[sudden citrus]

Closer to release they asked me to make a light menu-only player controller or something and I just couldn't without ripping out references to the main character for 3 weeks. Avoiding hard references is good practice, really, and repeating that "I probably won't have a problem with it" just means you will have a problem with it a bit later

[dark warren]

I shipped 4 games with hard references and had not a single issue with it

[sudden citrus]

There you have AI logic on the pawn, also a bad pattern

[dark warren]

😄

[sudden citrus]

I guess bad code is everywhere around us

[dark warren]

is is no logic, just a flag if this AI could do it at all

[sudden citrus]

belongs on the controller, or instead I'd make different BTs for it

[misty wharf]

The pawn/controller split is a bit of an annoying thing tbh

I have a bunch of things which technically should be in controller, but it's much easier to have it on pawn

for example you place pawns into level, you can adjust settings

but if those settings are in the controller? nope

[sudden citrus]

I only have that issue if I make a test level, otherwise I don't spawn pawns at design time

[misty wharf]

so you use some kind of spawner actor for it which does it at runtime?

[sudden citrus]

yep

I believe the Mass system has spawners too

I want my levels to be throwaway, the less manual setup in level entities the safer it is to recreate

[misty wharf]

yeah, my other project spawns all of it at runtime since it has a dynamic system for it anyway, but my shooter project has a lot of them placed directly into level at design time

although we also have a spawner for spawning enemies from result of events or such

[dark warren]

With the old State Machine I had all those flags at the Pawn and the controller pulled the values from it. As I'm working on Combat Snadbox games, I need to tweek every character with a lot of values and I tried spawners but it did not work out to well for me

[sudden citrus]

it also lets you avoid weird logic in the engine - there are different code paths for level placement and runtime spawning

[opaque fractal]

Hey guys, do you know if it's possible to use the Gameplay Debugger to debug the Perception Component attached to my Player Controller? I can only make it work with AIControllers.

[ocean wren]

Well yeah, why would a player need a perception component, given they've got a brain?

ok, given that we ASSUME they've got a brain 🙂

[misty gale]

A brain needs external stimuli .. duh! 😅

The more the merrier

[sudden citrus]

There's probably a way to get it working but I think player centric stuff can become so different that you're better off manually running raycasts, sphere traces and whatever

Try pressing tab for the free camera in GDT and aiming at the player

maybe there are keys to cycle target actors?

[normal sentinel]

Can an AI controller with a pawn that can fly be told to move to a point in the air? It seems to simply sit at ground level and do nothing.

[main heart]

Isnt that something to brag about?!

On getting back to basics, have a read at SOLID principles

[misty gale]

No, there's no navpath in air. You'd need to do custom input handling for that i believe

[normal sentinel]

Fair enough. I was hoping not to have to implement my own FlyTo task, but I guess I am.

[lone stump]

@normal sentinel you can make it move from a to b without following path. Make sure pawn has FloatingPawnMovement component and just make it do MoveTo without pathfinding

[misty gale]

I always forget about that 😛 Does this take collision into account? I suppose it does not

[lone stump]

Probably just basic penetration stuff, but there's no pathfinding, that part you would have to do yourself or get some plugin

[sudden citrus]

Havok has 3d pathfinding, but it costs money. And last I checked (3 years ago) they sold their UE4 integration as a fork. Perhaps now that the Chaos switch prompted an interface change, it's a plugin

[misty wharf]

You could probably do some kind of floating pathfinding via EQS and A*

eg. generate a set of valid points to travel to for example on level load with EQS and you can then have your floating pawns navigate using the points with A*

so you'd basically end up with a 3D grid pathfinder of sorts

[sudden citrus]

there are whitepapers around for flying pathfinding definitely

[celest python]

https://github.com/reidtreharne/Navigation3D

[main heart]

You may need right height function to lift up the points from EQS plane.

But yeah, may not be simple 🙂

[misty wharf]

Yeah it depends on how complex your level and such is I guess

[misty wharf]

this actually looks more or less like what I described lol

some kind of grid is generated and A*'d

[celest python]

Yep

[misty wharf]

Not sure how it handles grid sectors that are obstructed in some fashion tho

It does some kind of box overlap check but not sure how helpful that is

[magic jasper]

This is a decent 3D pathfginding plugin. Needs some updating though
https://github.com/midgen/uesvon

Also useless for non-flying stuff

Uses the same implementation as warframe

[celest python]

Nice

[ocean wren]

Dammit, my steamdeck won't arrive until Q3 😭

[mossy nexus]

any way to elaborate on how it works?

I was thinking about doing 3d pathfinding as bands in the air

[ocean wren]

Did you read the wiki? it literally says how it works, with a paper from Daniel Brewer and everything

[misty gale]

One is not used to such luxury, so one rarely bothers checking 😛

[mossy nexus]

it says it from a technical point of view, but I can't see how it's being propagated in world

other than "it's inside volume"

a visual representation would have been great

it does mention layers, but even so I'm not sure if they would correspond to e.g. air bands

[shell gazelle]

has anyone used the "move directly to" task with a vector destination in ue5.0? I can't get it to work with vectors. Works with actors though, but not their location vectors.

The vislog & source code tells me that the "OnPathFinished" got a something as a parameter that it couldn't handle:
LogPathFollowing (Log) OnPathFinished: Invalid[]
which makes me think of a bug

[shell gazelle]

okay.. it's a bug (sort of). Having "Project goal location" checked (it's checked by default) and not having a nav mesh will make the "move directly to" task fail. The vlog's don't catch this.
So basically if you make your prototype floaty characters wonder around to random points, it just fails silently unless you know to uncheck "project goal location".

[normal sentinel]

Can anyone shed light on what actually causes a task to be aborted?

In general is looks like basically, tasks are expected to be short lived, and you use decorators to filter tasks.

but if you do have a long running task (lets say flying to some random distant point) and you want to abort that if a BB variable changes.

What actually triggers AbortTask ?

ah, sigh~ nevermind, I see, abort task is protected.

It's for tasks to abort themselves, not an external caller to abort them.

I was hoping you could somehow write a service that could abort the child subtree

[shell gazelle]

in behavior trees, decorators can abort other nodes

[normal sentinel]

oh... the time limit one aborts the task its on

Cheers, let me have a look how it does that.

[shell gazelle]

This might help: https://youtu.be/iY1jnFvHgbE?t=904
If the long_running_task is on the right in the behavior tree, then a task or a composite to its left can abort it. It needs to have a decorator which has "observer aborts" set to true

[normal sentinel]

ooh, nice.

thanks~

[foggy pike]

Why would EQS query go through doors? Is there a way to have it test for navigable-ness?

oops I can do a path test lol

[crisp bone]

So I'm getting insanely large NavMeshBoundsVolume in my world. To the point where it's crashing the project. Does anyone have any insight on how to optimize NavMesh?

[lyric flint]

Have you tried navigation invokers.

[crisp bone]

I'll go google "navigation invokers" - thanks.

[lyric flint]

@crisp bone And for your sanity and troubleshooting purposes, after you learn about navigation invokers, and poke around by yourself, if for some whatever reason it doesn't work as expected, you can try and copy and paste the following settings as some sort of workable starting point in your DefaultEngine.ini of your project

[/Script/NavigationSystem.RecastNavMesh]
bFixedTilePoolSize=True
bForceRebuildOnLoad=True
RuntimeGeneration=Dynamic
TileSizeUU=2000.000000

[/Script/NavigationSystem.NavigationSystemV1]
bAutoCreateNavigationData=True
bInitialBuildingLocked=False
bAddPlayersToGenerationSeeds=True
bSkipAgentHeightCheckWhenPickingNavData=False
DirtyAreasUpdateFreq=60.000000
bGenerateNavigationOnlyAroundNavigationInvokers=True

But do this only when you are about to jump out the window, it's good for you to learned the manual stuff by yourself in the project settings GUI 😆

[crisp bone]

Thanks. Looks like it may be working, "P" in editor is showing nav mesh rendered strictly around AI Characters....

[thin chasm]

Dunno if this has already been answered before so apologies if it has.

Trying to solve this issue within this game I'm working on.

I have AI enemies that attack the player character and I've set up a move to for the enemies towards the player character when they're sighted, but when the player character jumps (and they jump quite high) the move to for the AI enemies fail due to the AI characters not being able to jump or get a path towards the player when they're airborne. Ideally I would want the AI to continue to follow the player but follow to the location underneath the player at all times.

I came up with the idea of line tracing down from the actor and updating a vector for the AI enemies to move to. Although this approach does work the vector is not constantly updated in the move to even though I'm updating the vector with a service (I realized this is probably due to Track Moving Goal option only works for actors and not vectors).
I've tried to see if I could edit the existing Move To code to do this trace but it doesn't seem like it would be the best way of approaching it.

What would be the way people would go about solving this problem?

[somber ore]

What is causing this to happen? It seems to happen randomly, sometimes when I hit play it works fine and the zombie runs straight towards me and most of the time it just spazs out like that
https://streamable.com/otf9eq

[urban rivet]

limit z level on the move 2

[daring osprey]

Hey, I have an issue, my second wait node fails instantly, even if I put more tasks to the right of it. Anyone might have any idea why is that?

[misty wharf]

if move to fails it usually means the point is unreachable, either because your navmesh is missing, the actor is not on the navmesh, or the point is not valid for some other reason

Visual Logger has more debug info on why movement fails

[sudden citrus]

I think he said the wait node fails. But maybe the actual issue is that the move node fails and the wait never happens

[misty wharf]

Wait should never fail so it's more likely the move to failed

[ocean wren]

Yeah, any failure of a child node would cause the sequence to fail so its probably the moveto node, as someone mentioned you can check the visual logger, but if the moveto fails it generally spits out why into the log file too.

[thin chasm]

Sorry, where is this located? 😭

[urban rivet]

do it programmatically 🙂 how are u calling a move to? if it's to a vector then only do X,Y keep Z same as the ai controlled pawn

[night robin]

Hello hello, what would you guys suggest to accomplish a simple flying AI pathing system?

[thin chasm]

Oh, i was doing this through the behaviour tree with the move to function, not c++

[urban rivet]

been a while but doesnt BT have a move to vector task?

[daring osprey]

Well the moveto node actually executes, the problem is once it ends it skips the following wait node. Is it possible the actor can t reach the exact position so it "fails" even when close to it and it causes the rest to fail too?

[misty wharf]

Yes

It won't cause the rest to fail, it just causes the sequence to abort

[daring osprey]

Whats the proper way of handling the z of the point it needs to reach? I gave the goal vector a custom position and I think it can t reach the z axis properly

[misty wharf]

You should be able to use project to navigation or whatever it was called

[daring osprey]

Ok cool, thanks!

Does that just ignore the z or calculates the goal z properly?

[misty wharf]

It projects the given point to the navmesh

so it should have the point on the mesh after using it

[thin chasm]

It does but this doesnt constantly update compared to if you use an actor

even if the vector is being updated with a service

[misty wharf]

Yeah you would have to rerun the moveto every time you update the vector

The lack of it auto-updating is a side-effect of how vector values are treated, they end up being new copies of the value, so when you update the BB value, it won't update in the moveto task, wherein if you assign an actor, it will keep reading the actor's position data so that can obviously update

[urban rivet]

they end up being new copies of the value

[crystal grotto]

Is there a way to let a single NavMeshBoundsVolume cover the whole landscape besides the obv scale it up to the moon way ?

[misty wharf]

You can edit it in brush editing mode and make it bigger that way :P

[crystal grotto]

Not quite the answer i was hoping for, but i'll just accept it xD

[misty wharf]

Yeah kinda wondered about it myself as well but haven't found any way of having it generate it in places without extending the bounds

[spark jackal]

anyone have information or documentation about the new AI systems in UE5, specifically the new StateTree system and MassEntity?

[celest python]

Check out DigitalFoundry's Matrix Demo review, its the best some kind of documentation/explanation so far I saw

Not a documentation per se, but 🤷‍♂️

[fresh remnant]

Has anyone had ResumeLogic not work? PauseLogic seems to work(pauses everything), but resume logic seems to keep the behavior paused

[fresh remnant]

nvm my bad 😄

[uneven stratus]

In my RTS I'm building, whenever I tell Units to attack something large like a building, they all move to the exact same corner of the building to attack. I think this has something to do with the navigation system finding the "closest" it can get; How can I make the ai take the real shortest path to it?

[misty gale]

Adjust the found location manually

[ocean wren]

find the navmesh edges close to the building position, take the radius of each unit and apportion them each a position on the edges of the building so that they line up along the edges sort of surrounding them

Basically, write your own code to handle it

[ocean wren]

You can look at the code 🙂

[misty gale]

Could be helpfull if the building could return its constraints

[ocean wren]

No need really, look at that image, the navmesh edges around the building are basically where you want your units to go

Just have to build a list of points along the edge

[misty gale]

Fair enough,

Plus ensures valid location

[ocean wren]

I do that for my squads and it looks pretty reasonable

I doubt anyone in RTS land does it any more complicated than that 🙂

[misty gale]

Shhh, im also in rts land 😂

[ocean wren]

The tricky bit is when you want your agents to go through doorways tactically 🙂

[misty gale]

Yeah that sounds troublesome. ^^

Glad im more towards city builder/resource manager than strategy really

All i need my ai to do is perform a few animations and move along splines exclusively

[ocean wren]

splines in an RTS?

[misty gale]

Its no traditional rts :p

Singleplayer , more towards frostpunk in some ways

[ocean wren]

oh I get you

[storm oracle]

Hello everyone, it's normal that a service calls an event 2 times in the same frame?

[ocean wren]

Is it?

[celest python]

Whats the callstack on 2nd call

[storm oracle]

The callstack is the same as the first time the function is called

[celest python]

Any possibility you have multiple instances?

Or how do you know it gets called twice in same frame

[storm oracle]

Is more like thee event that the service calls is launched twice

The call stack says is the same object on receive tick, the service is made to tick every 2 seconds. The breakpoint tho doesn't go back to the service function, but instantly goes to the event i launched, so it makes me think is being called twice. This in debugging the blueprints

[storm oracle]

At the end found why was called twice, cause i didn't see there was 2 input nodes connected. Didn't know about this.

[unborn jungle]

What is the difference between Nav Mesh Proxy Simple Links and Smart Links?

I see only documentation saying you can enable them but what would be the reason to use smart links over simple links?

[misty wharf]

You can subclass smartlink to provide custom behavior

For example if you have a door with a smart link, it could trigger the npc to play an animation to open the door, walk through and close it

Or it could trigger a jump animation, etc.

[unborn jungle]

Ah got it so for basic move to this launch pad to jump up, I don't need to use smart and can get by with simple?

My AI are dropping down fine but it seems they still just group up by the edge of a jump instead of jumping on the launchpad nearby, it feels like their target location is too far away from the navlink or something so they default to their non nav link behavior of just getting as close as possible without falling off the edge

[uneven stratus]

@ocean wren @misty gale sorry for slow reply, thank you for the help! I'll try experimenting with these ideas tomorrow!

[echo oracle]

What structure do you use in behaviour trees to get an enemy to do an attack that takes a certain amount of time and also stops the tree from continuing on?

[idle wigeon]

I'm pretty new to UE.. I need to do a lot of pathfinding, seems like the kind of problem that has already been solved.. is there some performant library everyone uses for that?

[idle wigeon]

Ahh nevermind it's built in.. google failed me.

[misty wharf]

create a custom BT task which triggers the attack action, and then listens to an event that is fired from the character when the attack has finished, and only then triggers Finish Execute

this way the BT will not advance from that task

[echo oracle]

What node do I use to get it to wait and listen?

[misty wharf]

create an event dispatcher for it in your character BP, then bind an event to it

[echo oracle]

ah. Awesome

ty

[hoary peak]

When will the tick rate of a task matter? I assume it matters for moving and delay/timers but is there anything else that's obvious that I'm missing? I'm not using sight/perception or anything alike that I assume would also be affected

[misty wharf]

if you mean BT tasks, the tick rate just controls how often the task's Tick is called

BT tasks are separate from actors, so it doesn't have any impact on how perception and such behaves

[hoary peak]

Yeah I'm talking about tasks, so if I don't run anything on tick inside a task the tick rate wont matter?

[misty wharf]

yeah

[misty gale]

Isnt tick rate used for bt eval?

[misty wharf]

Huh?

[misty gale]

Nvm, it was a task question 😅

Mis-read

[misty wharf]

Anyone know if there's a trick to support passing gameplay tags into parameters for EQS queries?

It seems extending FAIDataProviderTypedValue would be the way to go, but the other subclasses of that seem to use for example FIntProperty and such, and there isn't one for FGameplayTag as far as I can tell...

[misty wharf]

Okay well this is just confusing... are all parameters for EQS actually just converted into floats? 🤔

They all just are... floats...

No wonder there's literally nothing anywhere on how to do anything useful with parameters

It's because you literally cannot because it's hardcoded to only work with things that easily convert into numbers 🤦‍♂️

All I wanted to do was to create a test that would call a function to do some traces for a LOS check

but it needs a tag to be able to determine certain things for the LOS check...

Okay, maybe I can just directly poke the test instance like this... will have to test this tomorrow to see

TSharedPtr<FEnvQueryInstance> QueryInst = UEnvQueryManager::GetCurrent(this)->PrepareQueryInstance(Donger, EEnvQueryRunMode::SingleResult);
UEnvQueryTest_WeaponLOS* LOSTest = Cast<UEnvQueryTest_WeaponLOS>(QueryInst->Options[0].Tests[0]);
LOSTest->Foo = 1;

If this doesn't work then it's gonna have to be some really ugly hack I guess...

[simple crest]

that's some serious "that's right, it goes in the square hole" ing

where does the bool go? that's right, it goes in the...

[keen crow]

float?

[keen crow]

I gave up on hopes of parametrizing EQS at all and just wrote custom generator that one time that I needed and had the AI controller to implement an interface like IEqsQueryParameterProvider and used it inside the custom query

how do I make AI to perceive character in situations like this when say character's head is visible for AI but it can't trace the actor root? I tried putting another AIPerceptionStimuliSource component on the character but that one is not a scene component 🤔

[ancient wedge]

How do you guys handle dynamic AI with Navigation Invoker? If the target is outside of the Invoker?

[misty gale]

According to earlier talks here, having invoker on the target , despite there being "gaps" , allows the AI to find a path to a target

I have not tested or confirmed this by any measure, so take it with a grain of salt (or testing)

[viral spade]

hi everyone is there a way to use a classic boolean and not with the (is set) in behaviortree ?

[celest python]

No, it is already a classic boolean it just has an enum to determine what kind of comparision should be done

[viral spade]

so your telling me that is set = True and Is not set = False ?

[celest python]

yep

[viral spade]

Does conditional loop work like this to : is set = loop ans is not set = not loop ?

[celest python]

I never used conditional loop before

I generally avoid BTs

Just have an overall knowledge of it

But I dont know, try and see yourself?

Probably its same as regular for loop in C++

It will loop until your condition is false

[lyric flint]

why i cant put nav mesh bounds high in the level?

it stops showing that green area on certain height

[celest python]

There might be a setting for that in project settings

[lyric flint]

yeah went and searched did found nothing what i think will set it up

48000 units +Z is what im not able to put it in..

[viral spade]

😭 i was trying but it loop on true and false (cauz looping was activ in a sub segment 😅 )

[misty wharf]

Conditional Loop will loop if the value is set

[celest python]

So its same as if(somevalue) { forloop() }?

[misty wharf]

it's more like do { stuff } while(condition)

iirc it runs the nodes once and loops if the condition is true

[misty wharf]

So coming back to this EQS topic - this actually works.

I created a subclass of UEnvQueryInstanceBlueprintWrapper, and gave it a function SetGameplayTag(FGameplayTag Tag)

and added code into it like so:

    for(UEnvQueryTest* Test : QueryInstance->Options[0].Tests)
    {
        if(auto* LOSTest = Cast<UEnvQueryTest_WeaponLOS>(Test))
        {
            LOSTest->AttackTag = AttackTag;
        }
    }

Then, you can easily run an EQS query using the regular Run EQS node in BP's, choose this class as the Wrapper class, and call this function from blueprints to set the value directly in the test :P

It feels a bit roundabout but it works for adding effectively any arbitrary parameters to EQS tests... and you could use it with generators as well

[minor kindle]

using blueprints is there a way to add blackboard inputs to a BT task? im trying to recreate the Move To task but make it a spline, ive got some code that can do the spline it would just be ideal to pass the blackboard variable

[misty wharf]

set the type to Blackboard Key Selector and set it to be Instance Editable

[minor kindle]

thanks, is there a blueprint example of the Move To function? just something i can base the logic of my spline function on

[misty wharf]

Not sure. There are some Move To nodes that you can use with pawns or ai controllers

[minor kindle]

any suggestions for making a more smooth ai patrol? im doing an eqs query and its pretty good but ofc the ai snaps to move to that location. i dont want to use root motion if possible because i may have a lot of ai's running at once

[misty wharf]

You could tweak the EQS query so it produces more varied points, or give the character a higher threshold for reaching the point maybe so it doesn't need to reach that exact position

[minor kindle]

Yeah I’ve tried the threshold I’ll also try some more variability and maybe score points close to it higher

But doing that would mean more queries which could have performance ramification

It’s AI for a zombie so ideally there would be at least 10 at any given area

[misty wharf]

TIL "only blocking hits" does absolutely nothing in an EQS trace test

So that's another nice discovery :P

It seems to suggest that it would make it allow overlap and blocking hits if you turn it off... but... it does nothing. The trace is always only on blocking hits

So that was a fun 30 minutes wasted trying to figure out why it did not work the way I wanted until I looked at the code for it

Tweeted this earlier today and yyyyyeah... https://twitter.com/therealzomg/status/1503376797999771651

zomgmoz (@therealzomg)

Unreal Engine's EQS is really handy, but also feels like its design is kind of half-assed. Parts of it work very well, but other parts of it feel like they were just tacked on in a hurry.

For example, query parameters are just... weird. They all get converted into floats... ????

Twitter · Mar 14, 2022, 2:25 PM

[minor kindle]

When did EQS and BT release?

Is it like a new thing with UE4/5 and that’s y is not working perfect? It seems like a lot of AI YT tutorials don’t show using it

The unreal YT channel has a great vid on it tho

[misty wharf]

Yeah not sure, it's been in ue4 for some time I think

[minor kindle]

it seems like its been around for quite a while but for some reason lots of ppl show tutorials not using it

[misty wharf]

probably because it's kind of complicated to understand :D

[minor kindle]

i think its easier than trying to do it from blueprints

at least for the same capabilities

[misty wharf]

Yeah, it's not hard to use on a basic level, but figuring out the parts takes some work since it's not that well documented

[minor kindle]

the unreal official video on it is really good

so i did some stuff with the EQS and its better in terms of picking points to go to that make sense but the rotation isnt smooth

its pretty good tho

by making it prefer points close to the AI it breaks the previous behavior, making it basically hug walls to search an area more than before

i still think trying to recreate teh Move_To would be best

basically u get start pos, end pos, generate a spline, then move along the spline path until within range of the raidus

just not too sure how move to implements this

and for some reason my BT task isnt letting me make a timeline

i could make the timeline on my character but thats sorta not organized

[minor kindle]

ive got this which seems ok but it doesnt work cause the very first point is ridiculous, but subsequent points make sense

it starts at like crazy numbers and if it can try to input the next (before it auto deletes) it is a expected value

nevermind a null value can be anything in memory

can i make a BT task wait to finish execute till a custom function in a character completes?

[misty wharf]

sure

if you don't call finish execute it won't finish the bt task, so set up a dispatcher in your character for the function completion or such and trigger finish execute on that

[minor kindle]

i got it actually

i had to make a variable in the custom function for the BT Task

now only issue is the spline moves the character referenced from its eyes not feet

so it moves into the ground XD

[misty wharf]

you can probably offset it by cylinder height or something

[minor kindle]

get base eye height is close but not quite right

maybe cause the target location is based on the EQS?

now i gotta also get rotation splining 🤔

[minor kindle]

Maybe what I need is root motion

[kindred moss]

Did you get any help? I'm in the same boat as you.

[misty wharf]

his question is very complex and it can be approached in many ways depending on how it's intended to work

[minor kindle]

If the player is not close enough to see the AI it would be most efficient to simulate anything it would do with no actors

[dense halo]

Hey, does each nav mesh volume have it's own RecastNavMeshData, or is shared?

[misty wharf]

afaik it's all generated into a single navdata

[dense halo]

Is it possible to have 2 different nav meshes? I have a very large map and I'm using the nav invoker component so it doesn't build the nav data for the whole thing, but what I want to do is have another nav mesh that covers the whole map but with very large tiles

Is there a way to get the ai to use a nav large nav mesh with larger tiles when needed? I.e moving from one end to the other end of the map, since using nav invoker doesn't work

[misty wharf]

I'm not really that intimately familiar with how it works, but I know you can have multiple navmeshes if you have multiple different agents configured for it, as each agent can use its own navmesh

[dense halo]

I was trying to do that, but it seems to select the nav mesh depending on the size of the character? Not sure what function or variable I need to set to change the nav mesh used, other than changing character size

[sudden citrus]

EQS was made for Bulletstorm by the team at People Can Fly, who have ties to Epic (they were owned by Epic for a bit)

as many other AI systems it was never given the time to fully mature

I mean it's stable and all, but many use cases are just prohibitively complex. Like using data bindings.

lots of boilerplate

[misty wharf]

Or the fact that the data bindings only support values that can be marshalled as floats lol

[kindred moss]

For me, I'm trying to create a system where two AIs (a man and woman) move through a home preforming tasks at specific times of day. The complicated part is that the time of day is exposed to the user, so they can a dynamically switch from morning to night and anything in between. Therefore, I need the AIs to react accordingly, automatically changing what they're doing based on that time variable. They don't need to follow the player. Any thoughts?

[misty wharf]

You could have them look at the game clock and decide the action based on that

If the player changes the time, perhaps fire an event and have the AI revalidate their current action and choose a new one if needed

[kindred moss]

Thank you!

[misty gale]

Also some delegate to inform the AI about the sudden shift in time may be helpfull 🙂

[misty wharf]

Yeah that's what I meant by the event bit :)

[misty gale]

How did I miss that part lol

[kindred moss]

I'm a non-programmer, what's the Blueprint equivalent if you don't mind me asking?

[misty wharf]

event dispatcher

[kindred moss]

Perfect

[misty wharf]

I have something similar in my game to this - I have a game clock which has its time stored in my game state class, which also has an event dispatcher for when time changes by certain amounts

game state is easily accessible for actors, so it makes it easy for any AI or such to listen to the events

[kindred moss]

Okay, that's great to know. Sorry I'm very new to AI and have only been working in Unreal for 1-2 years. I will look into Game State. That sounds like it would solve one of the problems I was going to attempt to fix today. That is that the float variable which controls the position of the sun and also the time of day is inside a SunSky class. Therefore, when I try to access it from the UI, Character, BTT or BTS classes, there's no reference. I can't think of anyway to create a reference other then Get All Actors of Class on an initialize event or equivalent.

[dense halo]

does anyone know if it's possible to have 2 different nav meshes with different tile sizes/tile unit sizes etc, does anyone know where I need to look to find out where the nav mesh data actors are actually spawned??

[misty wharf]

Yeah, I'd have a central value in somewhere like game state for the time

You can have the sunsky update based on the time from state, and also other actors if they need it

btw you may find it convenient to use the DateTime type instead of a float value or such for tracking it, since it has builtin functionality for some date maths and other logic

Depends on how realistic your ingame time is I guess :)

[kindred moss]

That makes sense! I'll look into that as well. You're a huge help. I currently have just duplicated UE's SunSky Blueprint, and made a child which is the one we use in game with the location of Lausanne, Switzerland. SolarTime is a variable built into that Blueprint which is a float as you said. You're saying to convert that variable to the DateTime type and store it in the Game State class and go from there? Everything has to be extremely precise. The time of day and the position of the sun in the sky are two of the most important factors of our project. Thanks again.

[misty wharf]

I think DateTime supports time down to like microsecond or something

[kindred moss]

Yep ahah

That's good for sure

[misty wharf]

But yeah basically you'd use the DateTime in your GameState as the "source of truth" for what time it is in your game

and your other blueprints like the sunsky bp would read it from there, and do any conversions if they need to

[kindred moss]

That makes sense. I'll start doing some research now. Thanks for your help.

I only have one map by the way, is GameState still useful? There's only one player.

[celest python]

Anyone knows an example of normalization math for utility?

I had a look on EQS but its very specific to their system, I want to normalize the distance to 0-1

[misty wharf]

definitely :)

[misty wharf]

Oh boy

I found another fun EQS feature...

ActorsOfClass cannot use a baseclass in its search if it's abstract... so that's also nice

:D

[celest python]

Hmm, makes sense

Im surprised Epic managed to thought about something like this

[minor kindle]

i also found a bug not with EQS but the AI stimulus system, basically the first time i set everything up it works but if u close and reopen it doesnt until u check a particular box for the player (in terms of sight detection)

[misty wharf]

not really...you should be able to get by base class and those tend to be abstract I think

[celest python]

Were we able to place abstract classes to level? 🤔

I might be confusing, but I remember it was implying "notPlaceable"

So based on that thought that might be the reason

Since you can not construct it anyway

It wont be able to provide info about environment

[misty wharf]

well if you want to grab a set of actors having the ability to select abstract is useful

for example my npc actors all share a baseclass but the baseclass itself is abstract

now I can't select all my npc's with EQS, because it won't let me use the baseclass because they forgot to use AllowAbstract in the UPROPERTY declaration for it :P

[flint trail]

how is it usually handled, when NPC gets out of the nav mesh area somehow (how to bring it back so it looks more or less naturally) ?

[ocean wren]

don't let it get out?

project its position to the navmesh and teleport it back on

[flint trail]

well, say there is an explosion and it kicks NPC off the navmesh.

is there a way to check if NPC is outside of nav mesh and kill it ?

[ocean wren]

Well what do you think makes most sense for your game?

[flint trail]

teleporting NPC back would look like a hack, but might work if NPC fell of the cliff or something

[ocean wren]

Well, if they fall of a cliff, you can let the killz kill them

[flint trail]

if it's like a magical barrier separated area - killing it off would make more sense

I guess there is no out of the box built-in way to check if AI is inside navmesh area ?

[ocean wren]

Well, there are functions to check.. not sure if they're accessible via blueprint though

[potent bane]

ah thank you friend

[fickle tide]

https://docs.unrealengine.com/4.27/en-US/InteractiveExperiences/ArtificialIntelligence/BehaviorTrees/BehaviorTreeQuickStart/
So I'm going through this guide, but no matter what I try I keep getting the same error:

Blueprint Runtime Error: "Accessed None trying to read property Blackboard". Blueprint:  Enemy_Controller Function:  Execute Ubergraph Enemy Controller Graph:  EventGraph Node:  Set Value as Object```
I've tried looking online, but so far no dice there

I set up the Enemy Controller the way the guide did, but either I missed/messed up a step or the guide is outdated

[fickle tide]

This is the Blueprint event graph in my project

And this is the Blueprint graph in the guide

[fickle tide]

The Set Value as [x] nodes it's referencing are these two

So.. what am I doing wrong?

[fickle tide]

Looks like both of these are failing, hm..

[ocean wren]

When it says "accessed None" it means whatever it is doesn't exist.. which suggests either its working on the wrong class, or something hasn't been setup properly yet

Like for instance you haven't created the behaviour tree/blackboard in your begin play etc.

[misty wharf]

@atomic oak I would suggest reading the server rules unless you want to get into trouble with the moderators

[atomic oak]

oh ok did read them but did not see anything that was violated by this post

[misty wharf]

Yeah I just saw it posted in two places which would probably go against them :)

[atomic oak]

thanks for pointing it out where would you reach out to potentially interested people 🙂

[misty wharf]

Oh actually my bad, you posted it on the other channel many days ago

My excuse is that I just woke up lol

[atomic oak]

lol

[misty wharf]

Honestly it was probably fine here since it was AI related :P

forums or the ue reddit could also be worth checking

it looks interesting in general, but not really for my projects right now :D

[atomic oak]

Then put it back here haha

you got any link on the forums was checking a lot for them

[misty wharf]

https://forums.unrealengine.com/

[terse star]

Is that really something for #gameplay-ai ?!

[misty wharf]

Well we do talk about general UE-related AI topics here

[atomic oak]

it is hard to say it fits multiple categories haha

[terse star]

I guess!

It's just an odd one, like you say, Avatar!

[misty wharf]

I know @ocean wren likes all these machine learning things :)

[atomic oak]

yea if you guys got any contacts of individual dudes or studios that could be interested in having a demo session let me know would be really appreciated 🙂

for now its free so a win-win for anyone who wants to generate more 3D architecture content without coding haha

[mossy nexus]

I don't htink it's relevant for #gameplay-ai since it's a product being sold. I don't think advertising has a place on this server. <@&213101288538374145> is this correct?

[terse star]

Not even in #fab ?

[mossy nexus]

I don't know, is it on the marketplace?

looks more like advertising than a marketplace asset

[fair zealot]

:triangular_flag_on_post: Avatar#5475 received strike 1. As a result, they were muted for 10 minutes.

:triangular_flag_on_post: Avatar#5475 received strike 2. As a result, they were muted for 1 hour.

[knotty dawn]

so hard to read the #rules

[misty wharf]

Oh well. I told him it was probably ok here :P

It didn't look like it was being sold at least right now, he was just looking for feedback on it

[mossy nexus]

looks like advertising to me

[misty wharf]

I dunno, I guess asking feedback for your product is marketing in a sense, but it looked relevant to the channel's topic as we've discussed ML based systems for unreal before

[mossy nexus]

I wouldn't say so given how it was presented, and I guess it's in the #rules too

it's also against the rules technically to argue against mod decisions so eh

[misty wharf]

lol

yeah I wasn't trying to argue it either way, just wanted to point out that I did tell him it was okay and why I thought so :)

[terse star]

Against the rules to argue against mod decisions? Damn. That seems pretty draconian.

You should at least be able to state your case!

(Without being a dick about it)

[misty wharf]

Probably just so you don't start a big argument about it in public, I'm sure it's always ok to dm mods directly about it

[mossy nexus]

afaik you can in DMs, just not in public

[mossy nexus]

is this you asking for punishment as well because you were an accomplice? 😅

[misty wharf]

I mean I did originally tell him to not post it because I mistakenly thought he was crossposting lol

[fickle tide]

It looks like the official guide uses On Possess rather than Begin Play - could that be the problem?

Or is my implementation of it the issue?
(Long story short, I'm wanting to have all of the enemy AI logic in one place, and an enemy's AI depends on which type I give it [type being an enum variable on the enemy base class]. However, one of the types is "None", because one of the "enemies" is a training dummy. If it weren't for the lock-on system, I could just have the training dummy be separate from the base enemy class.
I've created only one blackboard so far, because I'm wanting to make sure the process works before adding the rest)

[kindred moss]

@misty wharf Sorry, this is a little unrelated to the AI part but it's all part of the process. I have been making some progress on my project. For testing purposes, I'm using the Events of Mouse Wheel Up and Mouse Wheel Down to adjust the time. However, I'm not sure how I should properly increase and decrease a DateTime variable. I'm trying to increase/decrease it by 1 second every time the event fires for example. Any thoughts? I'm really wondering how you do it in your project lol...

[misty wharf]

That's pretty much how it works in mine

You can create a Timespan value using the FromSeconds node for example, you can then do datetime + timespan to get a new datetime value

[kindred moss]

Weird...That's what I was thinking too but for some reason I can't add Timespan to DateTime...

Sounds like it's a UE5 bug

[misty wharf]

If you get your datetime value and drag from the pin, does + not offer a node to add timespans into it?

[kindred moss]

It does but it automatically disconnects and turns the Add node into Timespan + Timespan...It must be a bug. I've found a few people that have had that issue in UE5...

[misty wharf]

ah

[kindred moss]

I think I found a work around! Yay lol 👍

Does your GameState time tick?

[misty wharf]

I have a timer which increments it at certain intervals

If I needed it to increment faster than it does then I'd probably use tick

[ocean wren]

OnPossess would work, but have you set the character to possess? otherwise it might not be called.

[celest python]

@ocean wren

https://portal.productboard.com/epicgames/1-unreal-engine-public-roadmap/tabs/46-unreal-engine-5-0

[ocean wren]

Yeah, I looked at it, not sure its really going to be any use

You really don't want to run your ML on your own GPU to be honest

unless you have an A6000 like mine

Really most ML done with UE is done via a Kubernetes cluster

the inference via ONNX stuff is ok, don't get me wrong, but people will want to train models etc..

I think the use case for that ONNX stuff is really tiny models that run quickly, probably on CPU etc.

my use case is huge models run on clusters communicating with UE instances, also running on clusters

Kind of more interested in the geometry tools 🙂

[celest python]

Geometry Scripting thingy?

[ocean wren]

Yeah

I teach Procedural Content Generation to my undergrad students, so might get them to write a sort of "mini houdini"

To introduce them to writing graph editors if nothing else

[celest python]

Thats basically future of the game dev

[ocean wren]

Yep

I'm teaching them Houdini also, so figure getting them to write a simpler version would be good

Might do it in Unity though, we'll see

[dense halo]

is there a function that I can call to rebuild all navigation data on the UNavigationSystemV1? calling UNavigationSystemV1::Build doesn't seem to do it

[ocean wren]

Isn't there a Generate... function?

if I remember you can dirty a bunch of tiles and it'll regenerate

[mossy nexus]

it'll be the future when you don't need level designers anymore

[celest python]

I will probably want my level designers to work with procedural tools more often

Actually Ubisoft living that future today

Going mad with Houdini and other engine specific tools to create a new Far Cry each year

[celest python]

https://segmentnext.com/the-division-costs-200000-future-aaa-games/#:~:text=Thanks to Price and his,and AI is the answer.

[mossy nexus]

https://tenor.com/view/yikes-david-rose-david-dan-levy-schitts-creek-gif-20850879

[celest python]

We really need a GDC about how dying light 2 built their levels

[mossy nexus]

right but the quality is also that of a ubisoft game

[celest python]

Valhalla and Odyssey was fine in terms of art and level design

Same tools used

[mossy nexus]

I dunno

last I played was origins, and I was done with the game within 20 mins of playing it

if that's what people consider "good level design" then the industry is going down the drain

[celest python]

I havent played Origins

[mossy nexus]

I imagine it's the same as odyssey

[celest python]

But if you didnt like you probably have a point

[mossy nexus]

ubisoft is not known for making great games

they are known for making games cheap

they cut most of their good franchises and started making cheap open world games

that can easily be live opted

so yeah I'm not surprised that ubisoft would use procedural generation

but let's also not act like they are the industry leader in terms of design

because they are definitely not

[celest python]

Of course they are not, it's just many other 3A like Ubi would appreciate further improvements on those tools. Thats why geometry scripting could be a demand

Like how Marvel sucks but people watch it

[mossy nexus]

I don't think so. art can use procgen much more than design can

design you need intent, and that intent isn't free necessarily

the amount of complexity in designing something worthwhile, and having it tie into narrative etc. would be lost in procgen basically

[misty gale]

Ai driven proc gen?

Ship it !

[mossy nexus]

any procgen

but for stuff like genetic animations

sure

https://www.youtube.com/watch?v=K-wIZuAA3EY

[kindred moss]

Okay, I'm confused about some basic AI stuff probably because I'm about done for the day and am tired. I'll try to explain. So every time the time/sun changes in my level, I use an Event Dispatcher to signal the sun/time has changed. That's the gist. Now for the AI part. In my BT, when the game begins, I first want to play an animation of my two AIs getting out of bed. Then, every time the time changes, I want to sort through a Data Table I created in my BTTask_GetActivityLocation. Based on the game's time stored in the GameState, I want to select a specific row and, more specifically, its "ActivityLocation" vector. How might I do that is my first question? Then finally, still in this task, but after getting the corresponding vector, I will update the Blackboard Key called ActivityLocation. Then the AIs will move to that location, and then they'll play some sort of animation, say stuff, etc. Is the attached picture of my DT and task a good start? That's my second question. Any help is appreciated.

[mossy nexus]

@celest python

I'm sure you'll enjoy

so how this you fix this? really easy, I just didn't

this dude is the purest form of a programmer

it gets better

[celest python]

Uh @kindred moss sorry mate we were blocking your question

[kindred moss]

It's all good ahaha

[celest python]

I first want to play an animation of my two AIs getting out of bed.
This feels like an event so I would not do that in BT

So you just want to make your AI react to your world events basically?

And you want to have Data Tables that contains event names and related script data?

@kindred moss

Your system strictly enforces everything to happen in a specific form by bounding everything to struct's data that you used in DT

What I would do is using an abstract UObject and a system to manage/select tasks

And avoid BTs

something something utility system

[mossy nexus]

well work with what's already there IMO

[celest python]

what's already there
But BTs can not cover everything

[mossy nexus]

https://tenor.com/view/the-undoing-tv-show-noma-dumezweni-haley-fitzgerald-gif-24827178

[celest python]

Especially if you are feeding data by runtime changing values

[mossy nexus]

nah true I mean I do have my AI subsystem giving them tasks

in my case

but still

once a task is acquired

[foggy pike]

Hoy. I have the following issue:

If player fires gun near enemy behind a wall with a closed door, and the enemy runs off to investigate the sound, if the player opens the door the pathfinding will update to go through the newly opened door
Basically, the agent is pathfinding with a long path around to a spot, but I want the player to be able to open a door (which updates the navmesh) and go past. But the problem is opening the door creates a shorter path for the pathing request, and I don't want him to do that. How would one approach solving this? How do I make him "commit" to the longer path?

[celest python]

Usually doors should not affect navmesh

[kindred moss]

I have a scene (it's just one map), where the player can move around and change the time with a dial. This time is stored in the GameState class. Every time this time changes an event fires. When this event fires I want to go through this DataTable and select the row which corresponds to the time. This row will hold a bunch of different data but most importantly it holds the location where I want the AIs to move to or be. When they get there they'll do some AI behaviour, but when the user increases/decreases the time again, a new row in the DataTable and this new location will be selected, and therefore I want the AIs to abort whatever they're doing and start over by moving to the new location. I'll look up what you're saying though but I really would like to use BT. In the long run, I think it will help me make something more complex.

[foggy pike]

If I used navlinks would the agent commit to the longer path do you think?

[celest python]

Why not just request another move?

[foggy pike]

Sorry, not sure I follow?

Like why would requesting another move solve that? : o

[celest python]

Actually sorry since you are following a pawn it updates the path each ~0.1s

So it wont help

[foggy pike]

😭

[celest python]

Does this only happens once, like only in a specific part in a game?

[mossy nexus]

I think you can perhaps create a delegate based on navmesh changes?

but I reckon you may have to write your own MoveTo

zoombapup might know the correct answer tbh

[foggy pike]

ech god yeah maybe

[celest python]

A silly workaround in my head is move to location but update location only if door is not opening/closing. But idk you just should not let door affect navmesh at the first place

Why its affecting navmesh?

[foggy pike]

Sometimes I want AI to pass through them.

[kindred moss]

No, it's the main mechanics of the game. It's actually something that will be in a public place where someone can move a dial to change the time...The user moves around the scene and changes the time and the AIs react accordingly so you're always seeing them doing something different based on the time...

[foggy pike]

for context, this agent is a patrol monster that chases the player if it sees them, and I want him to chase them through doors

[celest python]

Then BT is a good choice, you just need to proritize the position of the node

Have a service that updates requirements of the AI on top of the main selector node

And have a boolean, if that boolean is true, do the action by sequencer, and preferrably by avoiding DT

[mossy nexus]

remove doors, keep doorways

the cheap option 😂

[foggy pike]

https://tenor.com/2hNo.gif

[celest python]

Why you cant do that though

Am I hitting a language barrier 🤔

[foggy pike]

Well THAT behavior works fine haha

it's just that if the player fires their weapon behind a closed door, and there's a valid path to that position a long way around like through which the player came, then I still want the monster (at least for now) to be able to move to that location

although realistically maybe they shouldn't

maybe I should just set the max navigable distance

[mossy nexus]

I get the idea of committing to a path

because realistically the AI shouldn't know that a new path has opened

[foggy pike]

pretty sure there's a way to set maximum path length right?

yea

[celest python]

Ohh you want AI to not use the door in that case?

[foggy pike]

yea if hte player opens the door AFTER they fire the weapon and the monster moves away

[celest python]

Ok

Can you check if nav modifiers can be a sub object (as scene component) in BP?

[foggy pike]

ah-ha they can

oh a scene component

I'm looking at variables hang on

ah yea they still can

[celest python]

yeah, so you also need a data object

they are fed with that object

and that object determines the 'cost' of the object

if cost is higher than other options, AI prefer most cheap one

Its up to you to change/modify/trigger/create that modifier

all 4 is the option

you can create the modifier volume dynamically, change the data object dynamically

you need to determine when you need to do that, like how will you understand when player is in that situation etc

then signal to nearby doors

etc.

at least this is a starting point

you can extend it to moon

[foggy pike]

cool

I'll have a look at that, thanks Barusu 😉

[celest python]

😂 Np

[faint basin]

Barusu

[foggy pike]

https://tenor.com/bh9Sd.gif

held off making the joke for as long as I could

LMAOOOO

[faint basin]

Nice name change

[celest python]

@foggy pike those data objects I was speaking of were NavAreas btw

Nav Modifiers require them

they hold the cost data

UE has built-in low-medium-high classes

and you can colorize them which is awesome for debugging 😄

[foggy pike]

ah cool

ahhh looks like they can't be scene components 😭

[celest python]

but that colorization might not appear before u restart the editor (i had fun times with it)

[mossy nexus]

nerds

[celest python]

yeah

my bad

they are actors lol

[foggy pike]

tragic

[celest python]

do you do c++?

[foggy pike]

oh lord no

[celest python]

then you are also forbidden from subsytem gang

[foggy pike]

wtf that's so sad

[celest python]

well, you gotta find a way to spawn/trigger them dynamically

[mossy nexus]

@foggy pike I would try and see if there's something like OnNavmeshChange and then do a LOS check or a sound check to understand whether the AI could perceive the path change, and only then allow the path to change

[mossy nexus]

welp you might be screwed

[celest python]

Miezsko and other gods of AI module dont like BP-only devs

[mossy nexus]

the AI module is half assed anyway

[celest python]

They dont like C++ devs either

[mossy nexus]

the hard truth 😂

[celest python]

😄

[foggy pike]

I've gotten by so far!

[mossy nexus]

I used to be like that

then I started with a little cpp

now I can't stop

please

[foggy pike]

heho

[mossy nexus]

send help

[foggy pike]

yea fr I'll learn it as I need

[celest python]

Pls dont be a better programmer than me, at least I'm better than you at something related with game dev @mossy nexus

[mossy nexus]

to be fair though I have a background in software development

so itwasn't my first language to pick up

[faint basin]

You seem to know a lot about AI Barusu, so while this discussion is going, I'd like to hop in and ask a question. Could a combat manager for AI be done in blueprints? (Combat manager as in if X amount of enemies is attacking the player, the remaining will sit back and not attack)

[mossy nexus]

I dunno I think you have me beat

but who knows

my AI subsystem is a neat 350 lines long

[celest python]

I would counter attack you with my 350 meters of level design but ...

[mossy nexus]

and I think another 175ish for the AI component

but I do mad stuff sometimes

like I use behavior trees for camera movement

[celest python]

My move to task is 413 lines long (in your face /s)

[mossy nexus]

I lied, it was 365 lines

some unimplemented stuff still that I need to do at some point

like global alarms

but eh

[celest python]

How is your game going on btw

Having improvements?

[mossy nexus]

I've been taking a break tbh. not been feeling super creative

I kind of need someone to bounce ideas off

like I keep having improvements that I need to make

but it's all just rewrites

[celest python]

Is there any possibility I can be useful on this?

[mossy nexus]

you'd have to play the game

I dunno, perhaps

[celest python]

Have you gotten that far to create a playable demo?

[mossy nexus]

it's semi technical

I got a playable first level

or used to, at least. I have been refactoring the meantime and not checked if it still is

and I want to refactor some systems to get rid of bugs

[celest python]

Are your refactorings mostly include c++ or are you also do crazy replacements with design too

[mossy nexus]

both

I have a system of "schools" that I have to figure out how to implement

and progress

[celest python]

Literally "schools"?

[mossy nexus]

no as in

"magic schools"

like different types

[foggy pike]

wtf ph.d simulator

[celest python]

😄

[mossy nexus]

if only, that would be a doozy

[foggy pike]

(average playtime 35064 hours)

[celest python]

Are they like some sort of ability unlocking things or actual playable chapters/sequences in the game?

[mossy nexus]

procgen could really help as well, making nonsense ph.d. writeups

[mossy nexus]

yeah they're unlockable spells

basically the entire game uses a spell system

and you use spells for everything

like if you get stuck in a dead end? there's probably a spell for that

can't talk to someone? there's probably a spell for that

and here's the kicker, spells require analog input

so more difficult spells are actually harder to input

[celest python]

Can I determine the end of the game by doing a spell in the beginning of the game?

[mossy nexus]

actually, yes

but it's a very difficult spell

and you'd have to find it and learn it first

[celest python]

😂 I knew you'd thought about this

[mossy nexus]

and it would probably kill you trying to cast it

so can I go with... "technically"?

[celest python]

Would be fair

What kind of system you use to manage high level layout of the progress in the game?

Old school gameplaytag + quest system combo in a subsystem or...?

[mossy nexus]

I use mana in the world for casting spells, and you basically pick it up as you move around. but it doesn't regenerate. however, you can always cast spells even with no mana, at the cost of your health

which means you can also cast spells above your level... at the cost of your health

[mossy nexus]

there are no quests

[celest python]

Sandbox game?

[mossy nexus]

more or less

every level is a domain of a boss

the boss isn't always out to kill you, but you're kind of trying to get rid of it

[celest python]

Hades intensifies

[mossy nexus]

killing the boss is the hardest option

but maybe you can play nice with the boss

and the boss will reward you

[celest python]

Can I drive the game by dialogues

Just by speaking

[mossy nexus]

there is almost no dialogue

[celest python]

Is this all because of a master plan or just tight on budget 😅

[mossy nexus]

I don't generally like dialogue in games, it often feels obtuse in trying to tell a story

so I let the world tell the story for the most part

I like how dark souls dialogue is

used sparingly, but intensely

[celest python]

You are really a fan of that

I love talking my way out though 😅

[mossy nexus]

it's all about being in the game and staying in the game

well get the talking spells

maybe that's a way 😉

[celest python]

Was a weird gif

[mossy nexus]

it's very much an experiment as well on how far I can take the concept of a "boss"

[celest python]

aaah spells are the boss

[mossy nexus]

well

I hadn't thought of that

or I kind of had

some spells have a mind of their own

but to have one as a boss 🤔

why not

even better

have a good spell that is easy to cast be guarded by a boss summon first

you have to defeat the spell to use it

I like it

[celest python]

🧠

Nice one

[mossy nexus]

but yeah in one instance there is no physical manifestation of the boss

the boss is the level

[celest python]

I'm hyped already

honestly

[celest python]

I probably found only documented thing in AI Module

FBBKeyCachedAccessor

And no one needs to know about it

[dense halo]

not sure if anyone else will need it, but you can just call RebuildAll on the nav mesh data actor.

    for (TActorIterator<ANavigationData> It(GWorld); It; ++It)
    {
        ANavigationData* NavData = (*It);
        if (NavData)
        {
            NavData->RebuildAll();
        }
    }

[celest python]

Does NavData->SupportsRuntimeGeneration() returns true when you try NavigationSystemV1->Build?

It might be why if its returning false

[dense halo]

not sure if this was for me, but I'm trying to do it in the editor, instead of clicking rebuild navigation button

[celest python]

I see

[final trail]

Hi, im trying to make my ai move to a actor in the level, but instead of going to where the actor is, it goes to the center of the map, any help?

[misty gale]

Center of the map is 0,0,0?

[dense halo]

hey, does anyone have an idea where/how ue4 stores generated nav data for when you have disabled runtime generation?

[misty wharf]

afaik same way as with runtime generation enabled :P

[kindred moss]

Hey all, thank you so much for the help you've been giving the last few days...I've managed to sort out all my initial problems 😀

Where do I look for understanding better how to give my AI unique animations and dialogue once he's moved to a location? Is this on the AI side of things or the interactive object side?

[dense halo]

I mean saving to and loading from disk, since it needs to serialise the nav data, does it not?

[kindred moss]

Here's my current setup. Based on the time of the clock which the user changes whenever they please, I sort through a DataTable I made which has some basic information about the activity such as where it's located in the scene. My first BTTask gets that info. Now I have an AI that moves locations whenever the time/activity changes. Woo, great! But now I want them to start doing stuff like talking and interacting with stuff in that space. I can't show my project unfortunately but I'll post the back end if anyone wants to take a crack. I'm just kind of lost on where to go from here...

https://share.vidyard.com/watch/er3rAWftL42wkJe9WocZwj?

[misty wharf]

afaik it gets stored in the nav data actor which gets generated into the level, or the actor has some representation of the data

[dense halo]

you mean ARecastNavMesh or ANavigationData actors? I've been looking through that but I can't find where it does it, I would like to store some other data (cover points) but not sure how to go about it

[misty wharf]

One of those I'd imagine would be it

Or at least contain pointer to the data - if you generate the nav data and then look into your actors list, you get the actor which represents it afterall

if you delete that actor, the data is gone

[lyric flint]

@dense halo I don't quite see the problem. Actors have a Serialize method. The same Serialize method works both ways to/fro disk. Look at ARecastNavMesh::Serialize for example. Roll your own inheriting from it, or change the source code as you see fit, if inheriting turns out to be too much drama. The Serialize method can handle any kind of possible data you can think of throwing into it, it's really just operator<<, if you have some basic ideas of how serialization works you should be all set.

[dense halo]

ok thanks, I think I was thinking into it too much since I saw something about URecastNavMeshDataChunk and Level->NavDatChunks I'm not sure if this is for level streaming etc or something completely different

[lyric flint]

I think the chunks are for world partition. Put some breakpoints inside some of the serialize methods, for example on the immediate Super::, and see where the call is coming from. my personal experience mostly is all in Level::Serialize, but the generic idea should still apply :)

[dense halo]

do world partitions have their own nav data actor? I haven't used it before so I'm not sure how it works

[lyric flint]

the key is that Serialize can handle any kind and type of arbitrary data

in world partitions I do not use static only dynamic nav mesh

[dense halo]

I have an octree that I want to save, still trying to see if it's possible serialize it automatically or if I have to save the items and then add them back in individually when loading, but my octree element has a TWeakPtr, is it possible to serialize this?
they are pointers to objects in the level but do you know if it's loaded, it will still reference the same object?

[lyric flint]

is best to use the scientific method. A small controllable sample/environment. As I already mentioned, everything goes through Level:: Serialize. So put the breakpoint there first. Further down in the same method there should be Ar << Actors I'm quoting from memory, so it may be slightly different. in your world outliner you should see all the actors in the level. One of them is the one you need. That's one the one you need to have a Serialize method, with a super:: in it. It has to, otherwise doesn't work :) put a breakpoint in it as well and see what data is about to serialize when you hit the save button on your dirty level. Later, closed editor, opened the editor, load the map in case, and the same breakpoints should it when loading. Previously the breakpoints hit when saving. Compare the data. Does it look the way it should? Tinker with it until it does :D

time to hit the sack though, but let me know how it goes

[dense halo]

I'm just going to leave it at dynamic generation lol, I think I have to use dynamic generation if I use navigation invokers on a large map

[dense halo]

hey, how does UEnvQueryGenerator run asynchronously? it doesn't inherit from AsyncTaks so how does it do it?

[celest python]

You dont always need asynctask

Its probably using task graph

[misty wharf]

It's not async that's how

It runs all on gamethread afaik but it uses timeslicing to enforce a time limit per frame

[dense halo]

is this the same for UEnvQueryGenerator or only UEnvQueryTest https://mercuna.com/writing-eqs-test/ (says here UEnvQueryTest uses timeslicing but can't find anything on ENVQueryGenerator)

I'm following the example of UEnvQueryGenerator_ActorsOfClass, and just using GenerateItems to get the items from an octree which contains the cover position, I want to run traces to see if the cover is valid given the player(s) so the ai can run to cover, so it makes sense to use a query test to do this right?

or should I do this as a BT Task?

[misty wharf]

Whichever makes sense for your project, there's no singular right way to do many things like this

having a test for it in EQS could make sense

and you certainly can wrap the query in a BT task to make some further decision based on it for example.

[dense halo]

is <FAIDataProviderBoolValue>.BindData(QueryOwner, QueryInstance.QueryID); used to get the value you set when you call SetNamedParam on the query? tried to put a break point but it seems to not be changing from the base value

[misty wharf]

Yeah

[dense halo]

do you know any tutorials or guides that can help me create my own UEnvQueryContext_Querier that returns a UObject* ?

[misty wharf]

I'm not sure if it can do that

I think they always return actors or vectors

[dense halo]

😭

[celest python]

EQS only interested in placeable things

or anything represents a value in the world i.e. vectors

[misty wharf]

It sounds like an attempt to have the context function as a parametrization system

:P

I guess you could have a custom function on the context which returns an uobject

but not sure if you'd need anything else for it to work

of course it wouldn't work with any of the existing generators or tests

[lyric flint]

is there a way in Blueprint to Refresh Nav Mesh ??

[dense halo]

you can make a c++ function

    UFUNCTION(BlueprintCallable, Category = "Development|Editor", meta=(DisplayName="RebuildNavigationData"))
    static void K2_RebuildNavigationData();

void UCoverSystemStatics::K2_RebuildNavigationData()
{
    FlushPersistentDebugLines(GWorld);
    for (TActorIterator<ANavigationData> It(GWorld); It; ++It)
    {
        ANavigationData* NavData = (*It);
        if (NavData)
        {
            NavData->RebuildAll();
        }
    }
}

that's the way I did it to run it on editor when I needed, you might want to pass an actor or something to get the world

@misty wharf @celest python do you guys know if it's possible to pass a list of actors to a EnvQueryTest from blackboard key? My AI basically has an array of player characters that it's aware of at a given moment (not all the players)

[celest python]

blackboards can not store arrays?

[misty wharf]

If you have a context which can read the appropriate BB key you could have the context provide it

otherwise you'd have to write a custom test or generator that can read it in some other fashion

and also yeah I don't think a BB can contain an array, you'd have to wrap it in a uobject or something first

[celest python]

if you store it in your ai character or ai controller you can check if they are in desired condition to be stored in that array and add

[misty wharf]

one way I can think of you could do it: Get the owner of the query, get its AI controller, get its BB, then read the value off the BB

[celest python]

by casting from querier

[misty wharf]

(this can all be done in a context)

[dense halo]

ok thank you, and yeah I didn't know you couldn't store it in arrays, I have it in my ai pawn right now so I will move it to the controller since it makes a bit more sense

I was hoping I could move it to bb and bind it somehow

[misty wharf]

Yeah if you want to store an array in the BB you would have to create an object to wrap it, and then store a ref to that object in the BB

this way you can then query the object and read the array off it

[lyric flint]

well due to I'm doing this from a modding point of view I don't have access to repack the whole game entirely only the stuff I add. I don't do C++ so thought is there blueprint alternative ??

[dense halo]

I couldn't find it

[dense halo]

hey, is the queryowner in FEnvQueryInstance& QueryInstance always the ai pawn?

like can I be sure that it's always going to be the pawn if you run the query from a blackboard service->run EQS

[misty wharf]

Usually it would be the pawn I think

You can set it manually to whatever if you use the run eqs node though

[dense halo]

from blueprint or form inside a service right?
or can you set it from the default run EQS service?

[charred lava]

Are there solutions to use a AI Rootmotion based Locomotion system with the Navigation System? I saw this video https://youtu.be/P1ZfIthFcV4 but I dislike how the AI Character turns to the next point before start moving. I thought about using the Motion Warping system to rotate the AI Rootmotion movement to the next destination point, but then he might overshoot a curve a bit and he might get stuck on the corrected path.

With rotating on place

with motion warping (rotation only)
Update: I guess with more root motion animations for more angles (8 angles) there isn't much rotation to correct with motion warping and with that it's less error prone. Right?

[misty gale]

How about using a spline for the motion warping?

Or in general start warping a tad before reaching the current target location...

Getting stuck can be a problem tho i guess

[charred lava]

Splines sounds nice, but then I need a system for dynamic created splines that stays in the navigation path, because I don't want them to be created manually.

[misty gale]

For sure

I've seen some examples of spline based movement, with pretty decent results

https://youtu.be/Ul0Gilv5wvY

In my faint memory this was somehow related, but i realize now thats its not very 😅

[misty wharf]

bp, I don't think the BT nodes have a selection for it, but I think they should default to the pawn

certain contexts like Querier wouldn't really work so well if it wasn't set to pawn

[haughty pelican]

Is there anyway to get an AI to move to taregt points without using a behaviour tree? As im trying to code a FSM to handle my AI?

[misty gale]

Many ways. Interpolation, simulating axis inputs

Pick your poison^^

[charred lava]

I love this plugin if you wanna use FSM. https://www.unrealengine.com/marketplace/en-US/product/logic-driver-state-machine-blueprint-editor It has a light free version with an example project for AI.

[misty wharf]

Or you know you could just use a regular blueprint with Move To nodes

which is probably the simplest way to do it :D

[misty gale]

Why keep it simple 😄

[ocean wren]

If you're using UE5 you can use the statetree

[dense onyx]

Hey! I`m trying to make my character fly by following specified path. If I set movement mode to flying, then actor following curve, but on surface only, not going up or down. Any ideas how to fix this?

[misty wharf]

If you are using Move To or such, those use the navmesh for navigation and will not fly

you might need a custom pathfollowingcomponent for it if you want it to work with moveto, but not 100% sure.

[dense onyx]

this is how it look like now. Yes, I use AImove to. I was trying to turn off NavMesh at all, since I get position from path. But nothing

[misty gale]

Aimoveto on timeline.. hmm

Looping even

Timeline is tick driven

Executes every frame

[celest python]

this symbol means the node is latent, you dont need to update those things in tick

[misty gale]

the system seem more designed towards interpolation really

[celest python]

Just setting location would be better

Instead of AI Move to

[ocean wren]

Whats with all the people trying to make flying AI?

Is that the newest indie thing or something?

[misty wharf]

Good question

I sometimes see patterns in questions on programming subreddits and it always makes me wonder did a popular youtuber post about that or something

[ocean wren]

Well, there was a time a short while ago where everything was "how to make genshin impact"

I figured something like that again

[misty wharf]

I'd like to see "how to make all the old games zomg played as a kid"

Now that's something I could get behind

[kindred moss]

How do I control the speed at which the AI Controller moves its Characters?

[celest python]

Set max speed on character movement

[kindred moss]

Okay, so I set the Max Walk Speed in the Character Component and then let's say I'm using a Blend Space, do I always have to adjust the max value of the Blend Space speed as well to match?

[misty gale]

Hit me up with that list !

[celest python]

If you dot product your speed and direction values it wont be a problem

[kindred moss]

Okay I'll look into that, thank you.

[celest python]

    Speed = FVector::DotProduct(ZGOwner->GetVelocity().GetSafeNormal(),
                                ZGOwner->GetActorForwardVector());

    Direction = FVector::DotProduct(ZGOwner->GetVelocity().GetSafeNormal(),
                                    ZGOwner->GetActorRightVector());

This way they always be in range of 0-1

[kindred moss]

Okay, sorry I'm a non-programmer but I can read that. Thank you. Let me get this straight. I create a speed between 0-1 and a vector that's unitized as well. Now those values plug into my Blend Space. Does it not matter that the range of my Blend Space is not between 0 and 1/-1 on both axis? Also, does it not matter that the speed axis is the same as my Max Character Speed Range laid out in the Movement Component? Mine for example is currently between 0 and 140cm/s. I'm just confused about how these values all work together. I'm sorry for being a nuisance but I really appreciate your help.

[celest python]

Btw sorry