A Better Way to Code Your Characters in Unity | Finite State Machine | Tutorial

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In this Unity tutorial, We'll use, from the ground up, the State Machine programming pattern to setup some simple logic for our enemies.
This is a standalone video that walks you through setting up a statemachine for, in our case, enemies. But due to its design it's a perfect setup for characters or NPCs as well, and since the states are self-contained it's very easy to modify.
There will be a Part 2 to this video that expands on the idea by dividing the logic of our states into ScriptableObjects, but this video is meant to act as a standalone, and so if you're interesting in learning how to setup a stateMachine, this is video for you!
Link to Download the FREE 2D Asset Pack seen in this tutorial:
veilofmaia.com/tutorial-asset...
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Contents of This Video: ------------------------------------------
00:00 - Why Use a StateMachine?
00:47 - What We're Going to Create
01:43 - Setting Up The Base Enemy Script
04:57 - Setting Up The StateMachine Framework
09:22 - Creating the Idle State Logic
10:15 - Creating Some Trigger Checks for State Changes
12:38 - Creating the Chase State Logic
13:19 - Creating the Attack State Logic
Who We Are-------------------------------------
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/ sasquatchbgames
#unitytutorial #unity2d #unity3d

[@masoncrowe]

Who else is doing tutorials like this right now?! Killing it man

[@sasquatchbgames]

holy CRAP!!!! Dude thank you SO much for your support, I don't even know what to say...That's so generous, Nikki and I appreciate it from the bottom of our hearts

[@chadmoberly7044]

Mason my man... doing lots of good in this world :)

[@BangBang-zb8sf]

Mason is the one who knocks

[@forbiddenbox]

thank you

[@dyanosis]

There are quite a few other Creators/dev doing this right now. Maybe have a look for "state machine tutorial Unity", you'll find at least a dozen.

[@Steinsdomain]

I feel like I'll need to watch this like 10 more times before i can even start keeping up xD awesome tutorial though, making it all so clean and look effortless is inspiring

[@fred1541]

As a student , I really learn a lot from your video, which makes my final report excellent in this semester, Thanks~

[@manningfamilychronicles1601]

This is really helpful and well put together. I loved the super quick and casual interface explanation I've been needing to learn that more in depth and that clicked really well how you explained it. Thank you sir.

[@shockingchris9809]

Just subscribed off this video alone. Some people may hate the amount of scripts here but I love how compartmentalized this is. So easy to follow, even as someone who has yet to implement a state machine yet. Great background story you guys have as well. Hoping the best for you two!

[@chadmoberly7044]

With the view counts increasing, and the super generous donor under this video, the future looks bright for your channel (AND studio!). Thank you so much for these videos that are honestly worth putting a price tag on. You guys take care!

[@sasquatchbgames]

Thanks so much! That really means a lot!

[@Titrationator]

A very good tutorial that explains this advanced concept in an easy to digest way. One of the best tutorials for anything I've watched.

[@vbamboo21]

This is so nice, informative constructions not only the state machine itself. And the explanation was spot on. Great learning source for newbie like me.

[@gabrielgauthier5611]

I think it's one of the best tutorial I ever encountered, I gained so much just by watching this 16 minutes video. Thank you so much for this !

[@Coditionals]

The worst thing about these videos is they have to be this long and you kept it as short as possible. All of this doesn't favor the youtube algorithm. Really great video! I won't go into tiny details I think that would make it better. Again, thank you so much for this!

[@AlcadraSoykan]

Nevermind, these tutorials are awesome.

[@yungefendi6480]

no way there is someone who can follow up on all this shit man

[@Jess_stpierre]

Very informative video! Love your explanations!

[@Tayiku]

Great tutorial, having a big file with 2000 lines is a hell when something goes bad. Would be awesome going a little deeper playing around with the AnimationTriggerEvent method, or using some good practices for where start animations on states, etc.. (I've seen some of your vids, seems you use professional practices, and that is what newbies like me need)

[@khanhhoangquoc1800]

Must be the best state machine i have seen

[@mehmedcavas3069]

nice. was waiting for that. great jobbb

[@Notreal76]

This is a great architecture. Thank you :)

[@psybergames7327]

Really top tutorial I was always curious of the scriptable object approach although never messed around too much with the idea myself. Although I currently working on a update for a game that already been prototyped and has shown enough interest that taking further. I have changed so much that new Enemy AI was needing done was originally going use a plug in but decided that I would be better to reduce the work load, but after thinking I seen your scriptable object approach. That led me back to previous video. Gave thumbs up and sub well deserved and look foward to the scriptable object use for my game as it will allow to do as you say give the exponential behaviours that will work great for my game as it will have procedural generation aswell so this give real variety abilities. So thank you and big ups for your videos

[@michaelshollaj6428]

very informative tutorial, great job

[@midniteoilsoftware]

Oooh, I love the way you showed 3 editor windows simultaneously :)

[@sasquatchbgames]

Thanks! I would have loved to have synced them up but it would have taken too ong :D

[@juanvalderrama644]

With this you saved my life, thank you very much.

[@iiropeltonen]

Good stuff. Been thinking about trying statemschines for animals in a game I'm working in.

[@mohamedmusthafa1057]

Wow Very Detailed Explanation ❤

[@tlotro625]

Good tutorial. Clean code. Propogates good programming habits. Respects OOP.

[@mracipayam]

You deserve much more views!

[@CodeRadGames]

great job as always!

[@arc3937]

that's really help full, thanks for this tutorial! im trying a multi statemachine for different behavior and that solve the problem for different types of interactions. i was now woundering is the quick override an extension or something, i type all the overrides and im getting crazy now

[@gbeebe]

As a professional programmer, who's predecessor's primary thought was "just make it work", that thumbnail hits hard.

[@sasquatchbgames]

I used to code like that once upon a time. So it hits hard for me too

[@coemgeincraobhach236]

Unbelievable, thanks!

[@alxdrksoul]

0:18 //move... LOL!!! thanks for the tutorial, as a beginner this is hard to understand, I might have to watch the video like 10 times before I totally get it, but who said programming is easy xD

[@BardockSSJL]

I'm getting a NullReferenceException when I try to call PhysicsUpdate(). But the error goes away if it's called from Update() instead of FixedUpdate(). Any ideas?

[@BardockSSJL]

I just found out Update() is not even being called.

[@user-dq3jv2xw5v]

I believe if you left Start and Update methods in Ghost class it somehow overrides Enemy Start and Update with nothing and, therefore, can't find some reference in FixedUpdate.

[@AndrewBotish]

Add "StateMachine.Initialize(IdleState);" in the Enemy class Awake function just below the state variables. The state has to be initialized first

[@ssbmPi]

this video is awesome and contains a bunch of information. you clearly know what you want to get done and seem to implement all of it pretty seamlessly. for me however i am just starting and looking to understand state machines better and this video moves pretty quick and contains a lot of information that im getting lost with, i implemented a state pattern from another creator 'iHeartGameDev' but a few of my more knowledgeable friends said perhaps it was a sub-par example/implementation of a state machine, even though it was functional. do you perhaps have another more 'beginner friendly' youtube video or article that you could recommend to me?

[@dong8912]

Would there be any performance implications due to any empty FrameUpdate and PhysicsUpdate calls? I imagine there will be lots of enemies using the Enemy script, some of which will not require FrameUpdate or PhysicsUpdate to be called. Won't this cause some overhead?

[@corvinziegler]

Great Video, I ran into a nullpointer exception in fixed update because it was called before the start method and had to get the rb component within awake function of my enemy class

[@kunterkurt9464]

At first, i really appreciate for making such great video. I want to ask about something. I tought, if we use getter and setter structure for both character properties and animation state machine, wouldn't it be more difficult to understand? I'm not expert of this, but maybe we can use switch - case for state machine, and for the character properties (such as durability or move speed) we can use getter and setter form. What are your thoughts on this? Thank you.

[@starblinky4091]

Good tutorial. At 10:15 I thought your enemy was varying his speeds and I was so confused. Trying to find a bug in my code or how yours could be doing that. After inspecting closer it looks like actually you just moved the hero which moved the camera and so it just looked like it was going at a different speed. The background is blank so it was hard to tell. Anyway. I found this pretty useful and will continue along. Thanks for the vid.

[@Poopymancer]

I have an issue with my visual studio that idk if anyone else has/knows how to deal with. I technically can work around it but it is very annoying. In this instance, when you got to the point at 3:19 when you clicked IDamageable to do the quick actions and refractories to put in all that code, my visual studio just doesnt do that. It doesnt recognize thee issue and doesnt know to put that code in to solve the problem. I've had similar issues in the past where it doesnt seem to understand how different scripts connect or something, idk if there's a setting i dont know about that i gotta change or something to make visual studio work better.

[@piper7521]

I have the same issue :\

[@TIWNGAF]

When should I use differenct state machines for different systems? I want to handle animation states programmatically in a state machine like this, I also implemented this state machine for my character behaviours. Should I use only one state machine with a variable currentBehaviourState and currentAnimationState or should I split both systems up into 2 different state machines? In my case, the animation states don't correlate always with the behaviour state. How would you guys handle this?

[@BMRG14]

Great tutorial! But can you please add "FSM" or just "State machine" in the title? (For the future searches)

[@JellyMudkip]

Hi! Ive followed the complete tutorial but I cant understand why the movement speed is so slow for me when is chasing the player. Idle speed is the same as the chase one, but chase direction is calculated 10 times small than the other one. Do you know what can it be happening?

[@carlbanfield8906]

one way you could make this video better is to add you using the final product state machine to easily build another enemy using the objects you just created, i know, you'll end up using more prefabs which in essence, are prefabricated lol but it still might help

[@muajin]

Hi. Do you by chance know how to export an android apk from unity? i keep getting some file when i press build and not the apk, also takes pretty long to build. I get a buildmethod error message at the bottom left part of the unity screen.

[@codenoob223]

The AnimationTriggerEvent is kinda slow how do i make it fast? I want to change to another animation after the current animation ends but it doesn't, if turn on animation loop time it takes two to three loops to take effect.

[@xRayed85]

Thanks for tutorial, quite informative but I found a problem. I guess you gonna have memory leaks with such cross reference since Enemy knows about State and State about Enemy. Am I right ?

[@MeguhFan]

This is really interesting. I'm not sure I've ever seen a enemy/behavior state coding tutorial like this. It's tricky for novices (like me), but I can see how this could save time in the long run making behaviors that can be switched around. Now, random question, I'm starting to interview indie devs on my channel for a series about developers talking about the games they're making, the tools they use, and games that inspired them. Would you be interested in an interview??

[@midniteoilsoftware]

I'd be interested in doing an interview.

[@youtubeofficial2749]

The AnimationTriggerEvent is kinda slow how do i make it fast? I want to change to another animation after the current animation ends but it doesn't, if turn on animation loop time it takes two to three loops to take effect. How do i fix this?

[@MrBa143]

Great tutorial! If i use imported animations for my 3D game, i need to use the Events tab in the animation clip, instead of the Events tab in the Animator panel (when creating them IN unity). They are quite different in behaviour. The one for imported animations relies on you providing a function name, and it will then try to find that function and trigger it. Is it possible to incorporate those events into the state machine? Edit: For now i've made a "EnemyAnimationEvents" script that sits on my enemy, which holds functions that the AnimatorController can find for the animation events. These functions will then access the 'Enemy' script and use the respective State instance to call the needed function. So if i have a MeleeAttackEnd event, i will have a EnemyAnimationEvents.MeleeAttackEnd function. This function will call the `_enemy.MeleeAttackState.MeleeAttackEnd` function. I intially wanted to make an empty GO on the Enemy called "AnimationEvents" which would hold seperate scripts with functions. One script per animation, but sadly the AnimatorController cannot search for functions in child objects, it only searches through the scripts on the gameObject in which the AnimatorController resides on.

[@akashrajak5811]

What are less expensive to check distance every frame. Thanks in advance

[@perssontm1628]

What I don't understand is, you create the Chase logic in the ChaseState, but what if different Enemies have different chase logic? I guess I don't expect any respond for such old video, but if anyone sees this you are very welcome to explain to me if this is how it's supposed to be used or if it's just an example.

[@nguyentrandinh8065]

I think you just create a new class name like SkeletonChaseState : EnemyState for Skeleton enemy or something else and override update in skeletonchasestate.

[@perssontm1628]

@@nguyentrandinh8065 Ah, makes sense I guess

[@--.--]

At this point I realised that my code is sh1t, thanks for showing an example for a better code

[@Ts1nd]

Did you put microphone near keyboard to record the clicks?

[@sasquatchbgames]

Lol! Yes. I love the clicks

did not understand shit xD! I will see it again and try to do it

[@brandonmitchell-kiss2533]

Shouldn't the reference to player be static, that way you don't need to call it in the constructor and all enemies will share one reference to the player??

[@NorinDev]

why your camera is so close? You spooked me

[@LmnoSneeze]

It's always surprising to me that people create scripts in Unity instead of directly in their editor. Creating scripts from your editor means you don't have to clean out the mono behavior bits and allows much higher flexibility.

[@patek2385]

Why not using Scriptable Objects?

[@ekekw930]

14:39 why not show us the better way?

[@cmdrelectrostruck1928]

I did this for his if else if (!enemy.IsWithinStrikingDistance) { _exitTimer += Time.deltaTime; if(_exitTimer > _timeTillExit) { enemy.StateMachine.ChangeState(enemy.ChaseState); } } else { _exitTimer = 0f; }

[@Arcann_bhp]

This is so fk complicated my pepega brain is exploding

[@mohokhachai]

Decoupling

[@vertigo2604]

well, it was interesting, but quite brainbreaking, at least for me

[@Coco-gg5vp]

First

[@user-ls7oo8mk6k]

Плохой пример. Не для игр. Вместо наследования нужно использовать композицию. Создавать врага из разных компонентов, а не создавать один класс Enemy и давать ему интерфейсы

[@Thefmc2010]

nice video, but state machines don't mean better performance, most of the times actually they aren't less performant. state machines generate more garbage and they produce a lot of cache misses. this is not a problem; 99.99% of the time, this will not be impactful for your game. however, 'performance' shouldn't be counted as a state machine's advantage.

[@danielrodrigorm4173]

what do you recomend, i have seen state machine done in the animator with behaviours but i dont know which one is better

[@IberianInteractive]

you know a lot of programming...but the part where you explain it to people is...horrible.

[@muajin]

Hi. Do you by chance know how to export an android apk from unity? i keep getting some file when i press build and not the apk, also takes pretty long to build. I get a buildmethod error message at the bottom left part of the unity screen.