Universal AI Behavior Toolkit

Now Available on the UE4 Marketplace


A possibly fix for above mentioned AttackeMeleeDistance issue (increase delay prior to setting the defaults).
Everything seems to work now smoothly, but didn’t tested the parkour system. Edited the spawner to respawn AI, and slightly adjusted related OnDeath spawn handling. If someone wants that code, post below.

@Jujaswe We ran into a problem. Our Physics Objects has a root that is a SceneRoot, Then under that we have a StaticMesh which is simulating Physics. So whenever Seek is called, it will run to the Actor Location (which is not where the StaticMesh is). For now we solved this by spawning that mentioned invisible NoiseActor which has the Approriate Tag on it. It however destroys it self after 5 seconds, which sometimes means that the NPC’s don’t reach it before it has despawned. When that happens, it seems like the BT gets stuck and can’t transition out of Seek. I added a PlaySound2d to end of BTT_MoveToBlackboard (as shown) and after a while (when NoiseActor destroys), this sound will play constantly, while the BT will be stuck in Seek.

Please advise…

Edit: I worked around the issue by not destroying the NoiseEmitter Actor at all. It obviously adds some overhead, but works. Would be nice to get your oppinion on it however.

@Jujaswe - super quick suggestion for the next update. Can you have the NPC that spawns a projectile be set as the owner and instigator of that projectile? (see attached pic)

In my projectiles, I tell them to ignore collisions with their owner so an enemy can’t shoot itself but can accidently shoot other enemies - Doom style.


this is blueprint,Maybe it’s my fault

This is my way,TargetsConsiderationRadius is 0 when AI moves and TargetsConsiderationRadius is 3000 when AI stops moving!

Find a lot of mistakes,but I haven’t changed the OwningCharacyer and ControllerRef,I don’t even know what it is,It just popped up in the morning,I hope you can help me,thank you!

This is in English

I just always got error message after migrating into my project.(when open the project)
“Can’t find file for asset”
I would be grateful for any idea why i got this errors.
Thank you!

Hello! I’ve been using your kit for a while, just recently created a new project with 4.18 and planning on using your kit for it again. I’m now getting a bunch of errors. I’ve made sure EQS is ON and I’ve even created a new AI Behavior Toolkit project and copy/pasted everything over to my current project, overwriting it. Is there another EQS setting I’m missing? I’ve looked through the FAQ PDF over and over, can’t figure this out. This is what’s “missing” even though I clearly see them all in their folders in Explorer:

That checkbox isn’t the right one as I see there @Yaremko, so go to the “Editor Preferencies” ➠ “General - Experimental” and there check in that block on the attached picture:

I think that is the problem with your project.

Collision seems alright, checked all that before asking.

I’m using FPS Kit. In step 7 on the Integration doc from FPS Discord says to do first image:

But, that doesn’t work. Target on Add Actor defaults to Self and won’t allow GET, and Actor Ref won’t allow Self, but will allow from GET?

So, I tried the second image just now.

I spoke to FPS dev, he said it’s an optional step. Not sure what to do other than test this last logic.

It Step 7 optional? If not, is my code worth anything, cause, as it is, step 7 is not possible.

@RoccoFX thanks for the feedback!

  1. You can change the AI’s Movement Mode to “Walking” and behavior tree when you want them to walk. And then when you want them to fly again, just change back to “Flying” and the original behavior tree.

  2. You could add to the BTS_CheckDistance to check if they are too far from where they started. Then call “Change Behavior” to force them into Idle.

  3. Just change the Rotation Rate from the Character Movement component. Like this -

I hope this helps.

I have a problem with the amount of AI Actors I can spawn.
I can only have around 50 working AI actors, the rest is just standing still.
This is a problem I have for a long time and I could not fix it myself. I need more actors to populate a more open world but it is not working with 50 actors.
The errors do not appear every time and I think it does not have much to do with it though.

I would love to fix this issue somehow.

Hey all, I have a few questions hoping to be figured out :slight_smile:

  1. How are the units/numbers in the details panel for npc measured? For things like view distance, target consideration radius, other distance trigger and so on, I press the ’ key for debugging and then numpad 4 to see wire/outlines of colliders - but it doesn’t appear to adjust the distances to any number changes… is there a way to view these changes so I can accurately see what the distances look like? Right now, enemies in an alley way (if far enough will not be bothered by the player until the player enters a hard coded perimeter) (see attached image).

  2. I’m having a hard time figuring out the delay trigger and getting to work correctly, it’s meant to add a timed delay before switching between behavior types, and allowing however many seconds of deviation, right? So if I put 5 second delay, with 2 second random deviation it will choose any number from 3, 4, 5, 6, 7 and then switch to the behavior chosen from the drop down?

  3. Is there a way to have a short skype session with the dev to have some one on one assistance?

  4. Where do I control the attack duration of melee attacks - for example if I want the npc to up to the player to melee for 2 seconds, then flee how would I achieve that?

  5. I notice sometimes there’s a state change from melee to flee (how I set it up) and the melee animation will play while the NPC is turning (please reference this gyazo clip at 0:44 seconds) The animation is a place holder zombie melee, but you can see when I jump over the npc - it tries to melee and turns away, looks odd…

  6. I’m checking out flying AI and out of the box they REALLY seem to be struggling by means of VERY twitchy movement. The human ai I have going so far show no problems like this so it got me thinking to check the AI Behavior project flying example map in an unaltered project, it works as it should. I’m using the right Player Tags for the airborne enemy to ID the player as a threat, but even on idle they won’t move to a random location - I checked and compared side by side both project/editor settings and saw no difference, I checked the AI itself to make sure and still find no differences. Is there a hidden variable somewhere that MUST be checked for the airborne AI to work with a modified player character? I have a nav mesh in my scene, but so does the example map and I saw in the notes that this was fixed in an earlier patch Please advise any solution to fix…

  7. There seems to be an issue with getting “work animations” going using the default shooter ai/skeleton. Even in the ExampleRPG map where there are work station points, civilian NPCs work no problem, the NPC_ShooterEnemy won’t transition to doing the jumping jacks like the civilian will (yes, there is a navigation path), please see it in action here…

Thank you for the amazing pack, it’s slowly making sense with all the documentation and YouTube tutorials!