Unreal Engine 4 Tutorial - AI - Part 1 The Behaviour Tree

[@stickyrice6513]

I really appreciate you taking the time to make this video. It's quick and ACTUALLY a tutorial rather than most tutorials that tell you what to do and not WHY you are doing it. Thank you!

[@pathos7527]

Important: In the beginning when you add your skeletal mesh, be sure to rotate it so the character’s face is pointing the same direction as the blue arrow. The blue arrow represents the direction that is considered forward for the character, so when it moves it will rotate the character so that blue arrow is pointed toward where it’s going accordingly. The animation is triggered regardless along with moving the character, so if you don’t rotate the skeletal mesh it will have your character appearing to run sideways or backward and look unnatural. The tutorial creator does do this, but doesn’t call it out loud that he is doing it, so if you’re following more off what he is saying like I was this would be an easy mistake to make and then be confused why your character doesn’t seem to be moving correctly. Hope this helps avoid some frustration.

[@maciejgrzeskowiak6241]

That's why he is running sideways thanks for the tip

[@ΝικοςΧατζημανωλης-π3σ]

[@pathos7527]

Maciej Grześkowiak Welcome! Glad it helped

[@tuhaggis]

I had this issue, thanks for the advice! I'll just piggy back off it and add that if the NPC isn't running on the ground, you should also check to see if the mesh is properly placed within the collision cylinder. My NPC was running sideways about a foot off the ground at first, but now it's much more natural looking.

[@tuomassandroos]

Thanks for pointing this out! Just came back to check why my character is walking funny.

[@Tailslide1970]

On UE5 the character will not animate following this tutorial unless you enable “Use acceleration for paths” under the character movement component of the AI BP

[@bradenwagstaff1234]

You beautiful beautiful human my goodness if I was looking for this comment literally a day earlier it wouldn't be here. Thank you thank you

[@lukepowell4737]

You my friend are an actual Legend, now my character has that sexy smooth run. Thanks a lot 👍👍👍👍👍👍👍

[@maxostlund9334]

Thanks bro! Also remember to use a skeletal mesh that is _simple and so for example SKM_Manny_Simple will work, but not SKM_Manny!

[@peterholmes7890]

Hi, my AI character asumes t-pose sand slides around. I tried this,but all it did was to drop the character into its idle pose but still slides around when changing location. Seems to be ignoring the state machine. If i connect the same character to axis inputs, it works fine. Hope you can help, cheers

[@martinroland8534]

@@maxostlund9334 Thanks for sorting the sliding out

[@0u73rh34v3n]

I gotta say, you're extremely good at getting information across. Straight to the point teaching style, friendly tone and no cringey fluff. Keep it up mate.

[@Andriy_Doc]

So far its the best video tutorial on the topic out of maybe 4 or 5 that I've found online. Kudos and cheers, man!

[@RyanLaley]

Thanks!

[@RedFlytrap]

Underrated channel, this was by far one of the quickest tutorials that got to the point super quick. Thank you for taking your time to make these.

[@dawnrigel4255]

For the past two days, I've been re-watching this video and reviewing my work, trying to figure out how I could possibly have everything exactly the same, but still not have my AI working. It wasn't until I checked out the Unreal tutorial for Behavior Trees for this same movement that I noticed I had "FindRandomLocation," "MoveTo," and "Wait" all coming out of the Selector node instead of the sequence node lol. Definitely the biggest and longest brainfart I've had ever!

[@mwilsonjr92]

You saved me.... I was doing something similar lol Thank you

[@dawnrigel4255]

@@mwilsonjr92 I made that comment hoping it would save others in the same boat XD It boosted my confidence a bit though. Really reaffirmed that 95% of the times I encounter issues, it's just me doing something wrong, and mistakes are fixable, usually lol. Happy deving!

[@convexadecimal377]

Oh man that was going to take me a more than a couple moments to notice, thanks!

[@NoMementoMori]

Underrated comment the very same happened to me lmao.

[@BridgesProductions2024]

I did the same thing... I'm a total fucking melt.

[@shaunjackson6366]

excellently put together with no fluff. I had my little cone moving around randomly withing 5 minutes and more importantly i understood why. I've looked through the next 5 videos and they all seem equally clear and concise. Thankyou very much

[@GamesandBacon]

I'm actually pleasantly surprised. Its hard to find clear and well done tutorials for UE. never looked at the AI but I'm entering a one man game jam so figured was about time ! Very useful ! Subbed :)

[@BOASolo]

Exactly my thoughts :D Subbed :)

[@bryelsmith9669]

This is me just being dumb but for anyone it might help, when you create the vector key make sure in the behvaior tree the find random location is set to "target location" (vector key) and not self actor. Very good tutorial though, all these videos are super helpful!

[@zachcarter1116]

Thank you this just saved me!

[@Classymarc]

This is one of the clearest tutorials I have ever seen! Good Job

[@xantishayde-walker4593]

You must be reading my mind. I was JUST thinking "I hope he does an AI Tutorial." You're the man!

[@RyanLaley]

Thanks, glad you like it. Can't wait to show more of it to you all.

[@Kubexis]

@@brutal6129 you are weird

[@vyomthakkar8209]

@@Kubexis wrong Sam is a SJW xD

[@levithefisherman3363]

@@RyanLaley can you plug other npcs into this if your making a large world with different enemy blueprints?

[@scjohnson243]

While I understand this is a 4 year old video, its a great resource. If your NPC is NOT moving go look back at your custom task, look specifically at "GetRandomLocationInNavagiableRadius" function, you have to connect the "Whte" EXEC path through that (the one in the video does NOT have the Exec paths - so he does not have to connect his).

[@rafaatrash]

thank you bro you saved me

[@Finestly]

Thank you so much i was searching for this so long 😭😭

[@RyanLaley]

Glad to be of a service

[@Zihanforall]

wait, I know you. You are HERE! wow

[@motorfiets4737]

How is your pubg project going on?

[@zarkiber]

nice

[@geostorm1o157]

look who is here its my boy finestly

[@despise9255]

Thanks for making this tutorial! This is the first video of yours I've seen so far, but it was the first result and exactly what I needed.

[@Zarsky88]

You deserve all the praise and more! Thank you for this excellent tutorial series.

[@DOAmaster]

Great tutorial, I am brand new to AI in Unreal and this cleared up a lot of confusion, keep up the great work!

[@fancydudemanbro1158]

I did everything step by step, I'm not actually sure where I went wrong. The NPC didn't move when I hit play, it wouldn't move, I changed around the wait time and still didn't work. It was probably just something I did. Your tutorial is great though!

[@HavokBWR]

Yeah Im having the same issue...

[@SoundsLikeGlitter]

Same issue

[@nickwinters2637]

Thank you for creating this series! It's been super helpful, and has taught me a lot of new things about Unreal.

[@massivetree7937]

Ryan thank you. Mad respect. Just went through the AI course on Unreal online learning and toward the end I thought my brain was melting. Thanks for the concise tutorial.

[@callmeleo9343]

Ryan... I just want to say that you cooked with this tutorial! Every tutorial always tells you to create a behavior tree where the AI starts wandering randomly...untill it sees the player, and all the tutorials to make it walk a certain path require a spline or a freaking patrol path etc... Your way literally makes it so all we need to do is replace the "Ai move to random point" to "Ai move to these specific points i want you to". Thanks a lot Ryan! Keep up on Cooking!

[@metri0n]

Finally got my dude running around. Big ups Ryan!! Just subbed because of this video!

[@geoffrey3668]

Thanks for this clear and simple tutorial! This makes AI easy for everybody!

[@RyanLaley]

Thanks, glad you like it

[@joshuacyr1017]

just want to say thank you for your generosity and all of the incredible tutorials you make, they're super helpful and you do an incredible job on them. I've learned alot from you.

[@ShadowSnake141]

This is explained far better than the official documentation, it's easier to follow, thank you! :)

[@patrickjesseman354]

Love your teaching style! Thanks Ry!

[@peterholmes7890]

Great tutorial series, very clear with good explanations and no fluff. Thank you. In my 'follow along' project, the behaviour tree seems to ignore the animation blueprint as my AI character just assumes T-Pose and slides around. Have you come across this or know the solution? Much obliged.

[@mx-gamesdev8287]

Really good tutorial series just what we were looking for, Good tutorials on AI Behaviour is hard to find, Thanks a lot MX-Games.

[@joofville]

Legend! This is exactly what I needed. Clear explanation of Blackboards and Behaviour Trees

[@JkouFiles]

Was trying to understand blackboards and ai, and this tutorial was very well explained. thx!

[@zsarfraz8938]

Nice tutorial(Subscribed). Also when I run the game, the AI moves around but doesnt have the animation. Any help would be greatly appreciated

[@nicholasconklin9586]

At 4:06 for anyone who is getting an error "This blueprint (self) is not a AIController, therefore ' Target ' must have a connection.", drag off of the target node and say 'get AI controller'. fixed the error for me. EDIT: This breaks when clicking play. Does anyone know how I can fix this as it wasn't an issue in earlier versions of Unreal Engine but it seems like it is one now More info: The event graph of NPC and NPC_AI sync. So whatever I add to the NPC_AI graph also gets added to the NPC graph. Because of this, I am not getting a compiler error in the NPC_AI graph, but instead in the NPC graph. It doesn't like that Target=self.

[@nikgiak2994]

I had the same problem. Make sure you run the "run behavior tree" node from your controller blueprint and not from your NPC character's blueprint.

[@momentime8582]

Just wanted to say thanks, this video is extremely well explained.

[@RyanLaley]

Thanks

[@AlmazovS]

Thank you! Your tutorial is very clear and easy to follow! One of the best tutorials about Unreal Engine!

[@JamalPennant]

All your tutorials are so clear and easy to follow even better than unreals own tutorial on this subject. Thanks!

[@nasaeyong]

Sometimes KZbin algorithm shows exactly what I need, great content thanks.

[@wmka]

So I searched "NPC AI Unreal" and it brought me here. Thank you and have a great day.

[@maxgomes92]

Behavior tree was not executing the second branch. I noticed at 13:17 that you have to click "success".

[@mujeebrahman5291]

TEMP FIX!!! In UE5, if your NPC is just sliding without any animation, go to that specific anim class (Eg- ABP_Many) -> Event Graph -> Look for Set Should Move to..(Comment). The first component inside is to get the current acceleration from movement component, disconnect this one. From the 'VARIABLES' tab on the left side -> under the Essential Moving Data, drag and drop 'Velocity' -> Connect this one, to node where the current acceleration was connected to. Compile and Save. PS : This is a temp fix that I found working for me, due to this change, may be something will break in the future.

[@MooNight008]

I solved this issue by enabling "Use acceleration for paths" under the character movement component of the AI BP, then duplicated the animation blueprint and changed the cast after the initialization from ThirdPerson BP to the npc one.

[@chinuonchaitanya8340]

you are a saviour ..i was stuck with behaviour tree..i want to build an adv combat system with sowds and all....now with the help of your tutorial i am feeling confident

[@chinuonchaitanya8340]

although my animation is not working

[@chinuonchaitanya8340]

oh..now its wokring..actully i am using a paragon for ai

[@dangerousmindgames]

Can someone tell me possibly why when I press play after setting up find random location my BP_Mannequin just stands there? He doesn't walk anywhere. I'm on UE5 - Does this mean there's something else I have to do?

[@aaronh248]

Can't wait to go through and finish this tutorial. Always been interested in A.I in games and that was one of my first ideas for a game within Unreal, a more A.I driven game. So I'll be following this one closely. I have seen and worked on A.I in other games and engines and I kind of cringed at first at that initial Navmesh lol. That looked easy but incredibly sloppy with all the gaps and missing areas and just the general way it was laid out. Glad you said you could manipulate and fix it up lol.

[@ivory6738]

This is a really well done and I enjoyed following this tutorial. Thanks Ryan.

[@Eric_Malbos]

A very clear way to start understanding and creating AI, great tutorial! Thanks a lot, mate!

[@potimuma]

My Behavior tree flickers and doesn't work Please help me

[@necromalice3530]

Thanks. Love your tutorials... keep up the good work.

[@yadav-r]

Thank You for sharing, and all the hard work that goes into content creation.

[@proertjs]

OMG, i learn how to make AI, thank you so much, i just start my journey as developer im subscribing

[@joonaskiuru8095]

Hi Ryan, I just want to thank you so much for these videos! They were really helpful when making my first game! I just made a devlog about it !

[@soldieroscar]

Wouldn't create a new task by clicking the icon as stated at 9:17, only two other already created ones came up. Had to manually ad the blueprint.

[@BuilderTrevin]

This is exactly what I needed to add to my arsenal of game development. I will be watching alot more!

[@sumitdebbarma1209]

wow sir awesome teaching i love it, specially the way u explain about each part completely. thankyou so much sir.

[@RaedAbbas]

My favourite AI Tutorial.. thanks a lot.. I just wonder if you want to add a smart link and the affiliation episodes please!

[@artwizardsam3238]

For Everybody having problems with the NPC not moving in newer UE version (or whichever versions), and has already tried every other solution in the comments. Here it is: Your NPC needs to be a character class not a pawn, in order to move.

[@VillagerJack]

How do i do that?

[@artwizardsam3238]

@@VillagerJack look it up bro I can't remember it.

[@VillagerJack]

@@artwizardsam3238 What exactly do i look up?

[@artwizardsam3238]

@@VillagerJack If I remember correctly, I think you just choose the character blueprint class, when making the NPC, just like at 1:00

[@VillagerJack]

@@artwizardsam3238 In replace of what? Sorry for being stupid but i did what is said in the tutorial what am i replacing?

[@madmodder]

Unreal 4's nav mesh volume is so nice. I remember having to manually place individual nodes to make nav meshes in unreal 2 and 3, and I fully expected that to be the case here.

[@MrColono]

here go again... It's my 4 time here making this project hahaha i love this series

[@awake_live]

A perfect absolute beginner tutorial, Thanks Ryan!

[@vladimirtabas6319]

My npc isn't moving.Everything is the same, do i am using 4.27.Any ideas?

[@codytaylor2220]

Great series. I'm following along in UE5, but I can't figure out how to get the NPC to change animations. I have the same mesh and animbp set as the original character but for whatever reason it won't transition. The NPC just slides around in the idle animation.

[@codytaylor2220]

Found the issue. The AnimBP includes a check for input before setting the "ShouldMove" variable. Eliminate all but the groundspeed check and it works.

[@magicgamestech9448]

@@codytaylor2220 Thank you. I had run into the same issue.

[@jcapo1803]

@@magicgamestech9448 could you explain further? Not sure what you mean by this, I am in the BP rn and I see ShouldMove and Groundspeed but unsure how to proceed

[@jcapo1803]

NVM FIGURED IT OUT YAY THANK YOU

[@Mitch_THe-MaDNeSs]

i followed the instructions almost exactly with just a few minor tweaks to the customizable stuff that shouldn't effect how the AI functions overall. I can't exactly figure out what went wrong, so does anyone know of any common mistakes i could have made that i could look into?

[@exstudent30]

Any ideas why my NPC is floating to each location without playing the Running anim ?

[@prakashleo3204]

Watched all the 12 videos. Thanks dude

[@Minerman]

Thanks to you I finally can become a game developer 😇

[@BaseRealityVR]

TOP video Mate, worked like a charm . good explanation and nice breakdown. No Filler :)

[@MetalMatt2510]

Done everything but the NPC won't move EDIT. Sorted, i had the FindRandomLocation, Move To and Wait coming off Selector not sequence. Now i need to find out how to get him upstairs as the green nav mesh doesnt go from bottom of the stairs to the top.

[@Jawa_Joose]

My "Set Blackboard Value and Vector" doesn't work. No matter what I put in the Vector node it returns some godawful 10 digit number when I check with a print. Using 5.0

[@mrcxx8694]

Great series, learned a lot. However, I don't use Blueprints so I converted everything into C++ and started an AI series of my own based on what's here.

[@DRAWKCABLLA]

the tutorial is just a wee bit fast paced but thats good, it makes people stay focused XD. great work man. Personal thanks for these videos

[@tsubarider13]

Simple tutorial that gets the job done. Thank you very much.

[@MassiveDrop]

Just got to your channel for the first time, really enjoy your vids! keep doing the great stuff. it's very helpful :)

[@unlimitedgamerworks6125]

If I wanted an NPC to move about, and be spoken two using the Dialogue Tree how would I do that. As currently when the Dialogue Tree ends the Logic is killed in the AI Controller. But I only want the Logic to be killed for the dialogue tree not the Behavior Tree

[@chapter-comics]

OG, This Ryan Laley guy???? Love him!!!!

[@tomas_ton]

amazing tutorial! thanks, waiting for the next one

[@RyanLaley]

See you next Thursday :)

[@unrealenginebroadcast]

amazing tutorial my friend the way you explain things is amazing and very clear and easy to understood :) Thanks my friend for this series

[@amadeuszhorzyk2130]

Not moving NPC bug FIX. Check if you changed your radius from 0 to 1500, like at 11:04.

[@HeyItzScotch]

this channel is fantastic

[@savacatalin9195]

I try to use one of the Paragon characters as my AI but he only moves to the random point without the walking animation, he just idly floats there

[@exstudent30]

did you figure this out? mine does the same.

[@senjunine8875]

Thank-you for being so clear and precise

[@Yoshi-bp9xg]

When I created the character blueprint, AI controller, Blackboard and behavior tree, why is there nothing in my details of the character? I tried so many times, after setting up the mesh and animation, and I re-open it, everything disappeared and I cannot do anything :(

[@atikghofar7449]

I REALLY LOVE YOUR VIDEOS BRO YOU HELPED MY FRIEND GRIND EVERY GAME ALL TO YOU THANKS BRO I LOVE YOU SO MUCH MAN!

[@remon563]

looking forward learning from this, thanks!!

[@darkserpent6884]

so i tried this with a custom model but it didn't work. i then restarted and copied the tutorial step for step but the AI still didn't move. any suggestions.

[@darkserpent6884]

i found the problem i had with the step to step part now i just need to figure out the model stuff.

[@Dudebat923]

If he is snapping to the direction of movement instead of actually turning around, go into the character class, disable "Use Controller Rotation Yaw," and enable "Orient Rotation to Movement." The Z value in "Rotation Rate" will determine how fast he turns. Also, if he is still using the idle animation while moving, you need to enable "Use Acceleration For Paths."

[@ReignSurvives]

Great video. I learned a lot. Very clear and to the point. I just came from the official unreal engine AI tutorial. It was so poorly done I couldn’t watch it all (cringe) so this was a welcome sight.

[@iamplaceholder]

Do you think the behavior tree uses a depth-first search or an iterative deepening depth-first search?

[@reecemungus]

Thankyou Ryan this was incredibly helpful 👍

[@dualperceptiongames]

Hi Ryan, Great tutorial. The only part that's not clicking for me though is how is the blackboard key data (in the task) getting passed in to the vector key (in blackboard)? Or is it simply that there is only one key so it defaults to that? I'm wondering what would happen if you had multiple tasks that should populate different blackboard keys with their output, how would each task know which key it is assigning the data to? Hope this makes sense. and again, great tutorial. look forward to seeing the rest.

[@RyanLaley]

In the behaviour tree you can click on a task and on the right hand side you should see a dropdown that allows you to choose which key to use. If you have only one key, then it will default to that one. However, as we get further into future videos you will see when we change that value.

[@Fettman89]

So how would I go about using this for a custom character? Obviously I'm not going to make a game using the mannequins, and have my own characters? I tried with my own but it just slides around in it's idle position.

[@sumitdebbarma1209]

hello sir the NCP after he reach the player location NPC keep pushing player character can u plz tell me how to solve this.?

[@TheRedflash777]

What if I have two or more vector variables in my blackboard, how should I get BB to know, which vector variable I use to store location info?

[@DronX_]

10:44 how to rotate the actor to new random position? because it movement is unnatural

[@cyberrb25]

I'd like if you included, either on the first video or in the message which version of Unreal you're using. Just so there is less margin for error

[@seanomik6176]

How could I go about making the AI rotate slowly instead of it snapping towards its travelling position. Like, give it a turning radius or something

[@michaelb1099]

is there a way to controlled when the tree is executed suxh as say i have the character answering my questions and going to where i want it to go then i want to execute the tree is there a way in doing this in other words execute on players command

[@xforcen233]

Sir, you are legend, please have my respect.

[@jcapo1803]

IF YOUR USING DEFAULY ANIMATIONS AND THE WALKING ANIMATION IS NOT WORKING: Check the event graph in AnimBP, look for the "Should Move" variable. Ensure ONLY "Ground Speed" and Greater Than are connected to the Set Should Move boolean. Disconnect the "AND" node from the Greater Than node, and it should work :)

[@jcapo1803]

BUT FOR ALL OTHER ANIMATIONS I have no fucking idea and it's really slowing me down. This default animation fix works up until episode 8 when he introduces an attack animation which is built for the UE4 manny and not UE5. I would very much like to know how to import other animations for example the Paragon Characters. They all just slide in idle.

[@jcapo1803]

Or the animation starter pack

[@murnoth]

Very Good, Clear Instruction! Thanks

[@FreakSheepVODS]

i have a problem and hope you can make a turorial on that i followed you hole tut on this but now when the AI is killed the controller is not and it will still attack you i did use the stop logic but that is Stopping BT but not Functions

[@plo173]

I've just made anims of my character and looking for some AI tutorial i Came to these absolut gold videos. But just realize i got all the characters movement base in root motion animations. If I implement a quick new anim blueprint withut RM anims, everything goes fine. Do you know how can i make an AI, and its behavior a BB, keeping the RM anims?

[@henryji6759]

How do you get the pedestrian behavior to work with an escalator?