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

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  • Опубліковано 12 січ 2025

КОМЕНТАРІ • 474

  • @pathos7527
    @pathos7527 4 роки тому +104

    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
      @maciejgrzeskowiak6241 4 роки тому +7

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

    • @ΝικοςΧατζημανωλης-π3σ
    • @pathos7527
      @pathos7527 4 роки тому

      Maciej Grześkowiak Welcome! Glad it helped

    • @tuhaggis
      @tuhaggis 3 роки тому +3

      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
      @tuomassandroos 3 роки тому +1

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

  • @stickyrice6513
    @stickyrice6513 4 роки тому +18

    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!

  • @dawnrigel4255
    @dawnrigel4255 3 роки тому +18

    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
      @mwilsonjr92 3 роки тому +2

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

    • @dawnrigel4255
      @dawnrigel4255 3 роки тому +1

      @@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
      @convexadecimal377 3 роки тому +2

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

    • @NoMementoMori
      @NoMementoMori 3 роки тому +1

      Underrated comment the very same happened to me lmao.

    • @BridgesProductions2024
      @BridgesProductions2024 3 роки тому +2

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

  • @0u73rh34v3n
    @0u73rh34v3n 4 роки тому +8

    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.

  • @scjohnson243
    @scjohnson243 Рік тому +3

    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
      @rafaatrash Рік тому +1

      thank you bro you saved me

  • @GamesandBacon
    @GamesandBacon 5 років тому +66

    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
      @BOASolo 5 років тому

      Exactly my thoughts :D Subbed :)

  • @Andriy_Doc
    @Andriy_Doc 6 років тому +7

    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!

  • @bryelsmith9669
    @bryelsmith9669 2 роки тому +4

    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!

  • @Tailslide1970
    @Tailslide1970 2 роки тому +51

    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
      @bradenwagstaff1234 2 роки тому +4

      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
      @lukepowell4737 2 роки тому +2

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

    • @maxostlund9334
      @maxostlund9334 2 роки тому +1

      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
      @peterholmes7890 2 роки тому +1

      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
      @martinroland8534 2 роки тому +2

      @@maxostlund9334 Thanks for sorting the sliding out

  • @RedFlytrap
    @RedFlytrap 5 років тому +6

    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.

  • @xantishayde-walker4593
    @xantishayde-walker4593 6 років тому +33

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

    • @RyanLaley
      @RyanLaley  6 років тому +7

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

    • @Kubexis
      @Kubexis 4 роки тому +1

      @@brutal6129 you are weird

    • @vyomthakkar8209
      @vyomthakkar8209 4 роки тому

      @@Kubexis wrong Sam is a SJW xD

    • @levithefisherman3363
      @levithefisherman3363 4 роки тому

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

  • @shaunjackson6366
    @shaunjackson6366 2 роки тому

    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

  • @Classymarc
    @Classymarc 4 роки тому +3

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

  • @Finestly
    @Finestly 5 років тому +54

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

    • @RyanLaley
      @RyanLaley  5 років тому +8

      Glad to be of a service

    • @Zihanforall
      @Zihanforall 4 роки тому +2

      wait, I know you. You are HERE! wow

    • @motorfiets4737
      @motorfiets4737 4 роки тому

      How is your pubg project going on?

    • @zarkiber
      @zarkiber 4 роки тому

      nice

    • @geostorm1o157
      @geostorm1o157 2 роки тому

      look who is here its my boy finestly

  • @despise9255
    @despise9255 4 роки тому +1

    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
    @Zarsky88 4 роки тому +2

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

  • @DOAmaster
    @DOAmaster 5 років тому +4

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

  • @fancydudemanbro1158
    @fancydudemanbro1158 2 роки тому +5

    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!

  • @nickwinters2637
    @nickwinters2637 Рік тому

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

  • @joshuacyr1017
    @joshuacyr1017 2 роки тому

    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.

  • @massivetree7937
    @massivetree7937 4 роки тому

    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.

  • @metri0n
    @metri0n 3 роки тому

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

  • @patrickjesseman354
    @patrickjesseman354 4 роки тому +1

    Love your teaching style! Thanks Ry!

  • @geoffrey3668
    @geoffrey3668 6 років тому +3

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

    • @RyanLaley
      @RyanLaley  6 років тому

      Thanks, glad you like it

  • @mx-gamesdev8287
    @mx-gamesdev8287 4 роки тому

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

  • @nicholasconklin9586
    @nicholasconklin9586 3 роки тому +1

    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
      @nikgiak2994 3 роки тому

      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.

  • @AlmazovS
    @AlmazovS 4 роки тому

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

  • @ivory6738
    @ivory6738 5 років тому +1

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

  • @callmeleo9343
    @callmeleo9343 10 місяців тому

    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!

  • @Eric_Malbos
    @Eric_Malbos 5 років тому

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

  • @ShadowSnake141
    @ShadowSnake141 4 роки тому

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

  • @nasaeyong
    @nasaeyong 2 роки тому

    Sometimes UA-cam algorithm shows exactly what I need, great content thanks.

  • @mujeebrahman5291
    @mujeebrahman5291 2 роки тому +4

    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
      @MooNight008 2 роки тому +1

      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.

  • @necromalice3530
    @necromalice3530 5 років тому +3

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

  • @wmka
    @wmka 3 роки тому

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

  • @momentime8582
    @momentime8582 5 років тому +2

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

  • @yadav-r
    @yadav-r 3 роки тому

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

  • @madmodder
    @madmodder 4 роки тому

    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.

  • @joofville
    @joofville 2 роки тому

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

  • @artwizardsam3238
    @artwizardsam3238 3 роки тому +12

    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
      @VillagerJack 3 роки тому +1

      How do i do that?

    • @artwizardsam3238
      @artwizardsam3238 3 роки тому

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

    • @VillagerJack
      @VillagerJack 3 роки тому

      @@artwizardsam3238 What exactly do i look up?

    • @artwizardsam3238
      @artwizardsam3238 3 роки тому

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

    • @VillagerJack
      @VillagerJack 3 роки тому

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

  • @JkouFiles
    @JkouFiles 3 роки тому

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

  • @JamalPennant
    @JamalPennant 5 років тому

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

  • @joonaskiuru8095
    @joonaskiuru8095 4 роки тому

    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 !

  • @chinuonchaitanya8340
    @chinuonchaitanya8340 4 роки тому

    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

  • @Dudebat923
    @Dudebat923 Рік тому

    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."

  • @prakashleo3204
    @prakashleo3204 5 років тому

    Watched all the 12 videos. Thanks dude

  • @proertjs
    @proertjs 4 роки тому +1

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

  • @MrColono
    @MrColono 2 роки тому

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

  • @sumitdebbarma1209
    @sumitdebbarma1209 3 роки тому

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

  • @BuilderTrevin
    @BuilderTrevin 4 роки тому

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

  • @BaseRealityVR
    @BaseRealityVR 5 років тому +1

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

  • @awake_live
    @awake_live 3 роки тому

    A perfect absolute beginner tutorial, Thanks Ryan!

  • @aaronh248
    @aaronh248 4 роки тому

    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.

  • @MassiveDrop
    @MassiveDrop 6 років тому

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

  • @Minerman
    @Minerman 3 роки тому +1

    Thanks to you I finally can become a game developer 😇

  • @unrealenginebroadcast
    @unrealenginebroadcast 4 роки тому

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

  • @tsubarider13
    @tsubarider13 4 роки тому

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

  • @tomas_ton
    @tomas_ton 6 років тому +5

    amazing tutorial! thanks, waiting for the next one

    • @RyanLaley
      @RyanLaley  6 років тому +1

      See you next Thursday :)

  • @maxgomes92
    @maxgomes92 4 роки тому

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

  • @zsarfraz8938
    @zsarfraz8938 3 роки тому +4

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

  • @atikghofar7449
    @atikghofar7449 2 роки тому

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

  • @biggzbunny5755
    @biggzbunny5755 4 роки тому

    Nice! Found useful and subbed. Very clear and well taught!

  • @TheArtist441
    @TheArtist441 3 роки тому

    This is incredible. Thank you, subbed immediately

  • @remon563
    @remon563 6 років тому +3

    looking forward learning from this, thanks!!

  • @senjunine8875
    @senjunine8875 4 роки тому

    Thank-you for being so clear and precise

  • @DRAWKCABLLA
    @DRAWKCABLLA 4 роки тому

    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

  • @peterholmes7890
    @peterholmes7890 2 роки тому +1

    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.

  • @HeyItzScotch
    @HeyItzScotch 4 роки тому

    this channel is fantastic

  • @JamalBakari
    @JamalBakari 5 років тому

    Well done, I'm needing this in my project now!

  • @Mainman0011
    @Mainman0011 5 років тому

    wow thank you for this tutorial! I've honestly been fighting to learn this over the past 8 hours. . . Within 30 minutes or so I now have basic npcs that run around mindlessly XD

  • @jcapo1803
    @jcapo1803 2 роки тому +1

    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
      @jcapo1803 2 роки тому +1

      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
      @jcapo1803 2 роки тому

      Or the animation starter pack

  • @dulceruizrobles3373
    @dulceruizrobles3373 5 років тому

    Such a great explanation, thank you for this video!

  • @soldieroscar
    @soldieroscar 4 роки тому

    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.

  • @reecemungus
    @reecemungus 11 місяців тому

    Thankyou Ryan this was incredibly helpful 👍

  • @chapter-comics
    @chapter-comics 4 роки тому

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

  • @dangerousmindgames
    @dangerousmindgames 2 роки тому +2

    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?

  • @amacias2012
    @amacias2012 3 роки тому

    Nice video, good explanation, step by step.

  • @mrcxx8694
    @mrcxx8694 5 років тому +2

    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.

  • @amadeuszhorzyk2130
    @amadeuszhorzyk2130 3 роки тому

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

  • @ReignSurvives
    @ReignSurvives 5 років тому +2

    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.

  • @lionellaurent108
    @lionellaurent108 3 роки тому

    Thank you soooooo much for this video, it was exactly what i was looking for.

  • @Voxiiit
    @Voxiiit 4 роки тому

    Thanks for your video, it was super clear and enjoyable :)

  • @potimuma
    @potimuma 2 роки тому +3

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

  • @GSC5
    @GSC5 3 роки тому

    Good job, Ryan 👍

  • @murnoth
    @murnoth 2 роки тому

    Very Good, Clear Instruction! Thanks

  • @RaedAbbas
    @RaedAbbas 4 роки тому +1

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

  • @mahmoudengin2227
    @mahmoudengin2227 2 роки тому

    I hope you post a video with all the adobe cracks. As always, you are the best, the crack works great

  • @jennifermeier3873
    @jennifermeier3873 3 роки тому

    awesome, super well explained ❣️

  • @imadqadri
    @imadqadri 4 роки тому +5

    This man needs more subs... no joke :)

    • @CosmicPlayR
      @CosmicPlayR 4 роки тому

      I agree and, therefore, I am subscribed!

  • @sumitdebbarma1209
    @sumitdebbarma1209 3 роки тому

    u are better than those people explaination who sell course on Udemy. i wasted money i think buying course on udemy.

  • @timulodeadline872
    @timulodeadline872 3 роки тому

    I like this guy, he gets on with it.

  • @xforcen233
    @xforcen233 3 роки тому

    Sir, you are legend, please have my respect.

  • @JohntheWeir509
    @JohntheWeir509 2 роки тому

    Time to grab the popcorn and learn some stuff

  • @HenceIVth
    @HenceIVth 3 роки тому

    If you have a problem that your ai does not move. I went to 'Build options menu' -> under navigation click build paths. In case that helps anyone.

    • @HavokBWR
      @HavokBWR 2 роки тому

      Where do you find "build options menu"? Is it in details when you select something or is it in a window?

  • @savacatalin9195
    @savacatalin9195 4 роки тому +2

    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
      @exstudent30 2 роки тому

      did you figure this out? mine does the same.

  • @Skycrafter328
    @Skycrafter328 5 років тому +1

    Awesome! You are king! Subscribed :)

  • @aluckyshot
    @aluckyshot 4 роки тому

    You're frigging awesome! Thank you very much for helping newbs learn.

  • @mch43856
    @mch43856 4 роки тому

    Really clear and well done tutorial ty man

  • @mikenortheast6393
    @mikenortheast6393 2 роки тому

    Really helpful stuff! :D

  • @DronX_
    @DronX_ 4 роки тому

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