How to Code a Simple State Machine (Unity Tutorial)

In this video, I'm going to teach you how to code a simple State Machine in Unity.

#Unity3d #UnityTutorial, #GameDevelopment

Have you ever written a method with two paths of execution? It probably had an if statement based on a member variable, right? But then your requirements changed, and you added another condition to handle a new state. And I bet they change again, over and over, until your code became a mess of hard-to-read flow logic and conditional statements.

If that's you, then you should learn about State Machines. State Machines are an implementation of the State Pattern, a behavioral design pattern that enables an object to control its internal behavior at runtime. In this Unity tutorial, I'll walk you through the implementation of a simple State Machine that handles the logic of a turn-based battle system.

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[MartyFoxy]

Wow, I've never seen such tutorial before. Explaining patterns in "question-answer" dialog is really easy to understand. Classes scheme is also really useful. That's what I've been looking for

[shaunyitisme]

That new style of pair programming / mentoring is really nice to understand what you're showing. Nice job, I hope you gain more viewers!

[julianerickson]

I started running into the problem of if-statement spaghetti as you mentioned and this tutorial was very helpful in transforming my existing code to the state machine pattern. Thanks a lot.

[ginocode]

Wow never seen someone do the sketch-like tutorial without coming off as either cringey or condescending. This was really well done and actually proved that a tutorial like this can work to great effect. Great job!

[donixdev]

17:45 That sneaky 2f transformed to 0.2f

[ZOMBIEBUSTR]

It is amazing to me that the conversation at the beginning of the video is the exact same thought process I had before looking for a refresher video about State Machines. and for this exact situation and project type as well. I'm amazed the first video I opened fits so well with what I wanted.
Great video, I love how you add a bit of explanation about why and when to use this pattern. It is as important to know about the pattern as it is to know when to use it.

[TackleProd]

I've seen them all, but you're one of my favorites to watch right now to learn Unity!

[holmbergen]

I've implemented this for my weapon system (still working on some issues).
It works great! It's actually been quite fun to work on the different states - it's so simple and keeps my code clean compared to the mess it was before! Thank you Charles :)

[SigmaChirality]

I spent 2 days writing then deleting state machine code for my game. Then I watched this video, and it resolved the issues I was having. Thank you.

[modiddymo]

I just used this tutorial to implement a FSM with the state pattern in a project I'm working, and I love it! I can now add more states as my battle system gets more complex (and I think it will). And it's so much easier to reason about the code that's already there. Thank you so much for this! Keep it up!

[brianwilson]

you have such a good relationship with yourself my dude, good tutorial

[shkkate]

Thank you a lot!!! Your way of making it an inner dialogue rather than monologue is best way not to get frustrated when following the tutorial🤟

[doge]

this is so freakin cool, why did I not understand this sooner when I first watched the video

[thethirdkate]

Great video, just another comment to say that I enjoyed the question/answer format - it's very reassuring to have my noob questions answered like that!

[nGAGEnline]

Wow, this pattern is amazing. It makes enemies yield when their currentHealth is less than twice their totalHealth :D
(silently fixed) typo aside, ... Amazing delivery on explaining the concept of a basic state-machine. I love your videos. Informative as well as entertaining :)
Keep it up!

[eter_inquirer]

If only learning from your peers was this smooth sailing

[Kandyman]

That was the best state machine explanation and very creative alternating state presentation. I get it. This sir, is worthy of the Infallible Code channel name. We're this reddit, I'd give you gold.

[dweebosupremo]

Thanks for this vid. I appreciate the human touch of the "skit" parts.

[ZoepX]

This was one of the best tutorials I have ever had the pleasure of watching in this website! thank you so much!!

[JackKell]

One small improvement that could be made so that you did not have to implement an Attack and Heal method in the base State class would be to have the battle system generate AttackButtonPressed and HealButtonPressed events. When a BattleState is created it could choose to subscribe to the events that it cared about such as Attack and Heal and could make decisions based on that. This would scale better, decrease coupling, and improve readability / code intent.