State Tree 5.5 - How To Get, Set & Bind Parameters & Use New Property Reference Node - UE5 Tutorial

[@karlbovski1656]

Having the **get property ref** Node is a nice addition to the system. I was using Variables on the Context actor to achieve more or less the same results but this makes the StateTree even more agnostic and flexible. Thank you for the clear explanation!! 👍

[@Three_Ways]

It's a great feature, as it allows you to use the parameters list as a blackboard like in Behaviour trees, to write back values. Needed workarounds before this.

[@unreal_metronomus678]

Very well explained, thanks!

[@Three_Ways]

You're welcome!

[@trulypedanticgaming]

I don't know who you are, or how you know it all, but thank you so much! This stuff is all so new, and the documentation so lacking, your videos have saved me so much trial-and-error headaches. You are greatly appreciated! How do you know so much about the State Trees?!!!

[@Three_Ways]

Lots of trial and error, trying to work out how the logic works. Not a lot of documentation or videos on this to learn from. Glad it helps.

[@trulypedanticgaming]

@@Three_Ways You remain invaluable in my implementation of AI and StateTrees. I truly appreciate you.

[@freyaniczdigitalartist2303]

Have you found 5.5 pretty stable regarding state trees?

[@Three_Ways]

Overall it's pretty stable and gets better with each release. Some odd things will cause it to crash the editor, but you'll learn to avoid them or workaround them.

[@SaschaRobitzki]

@@Three_Ways For the past few weeks I had only rarely crashes with 5.5.0, only when I did something stupid in C++. 5.5 is very stable for me (still Windows 10), though sometimes the character seems to ignore the AI, usually after launching the project as described in my other post here.

[@SaschaRobitzki]

Quite often, my character with the AI controller doesn't seem to be controlled by it. I replicated your project here, and it works as yours, but once I close the editor and relaunch it with the project, the character doesn't respond anymore. Often I just need to reload the map that had already been loaded at startup, and everything works again. But it's still irritating because I couldn't figure out why this is happening.

[@trulypedanticgaming]

Try recompiling the state tree (even if it says compiled) if it isn't working as expected, I think it is a bug.

[@SaschaRobitzki]

I just realized I don't have the tick marks for the tasks in the state tree in 5.5.0-release. Do they only exist in the Mac version?

[@SaschaRobitzki]

Okay, you can still disable and enable tasks. The option is in the right-click context menu on the task item.

[@Three_Ways]

Looks like it’s Mac only exposed, but it doesn’t work. If you click it, the editor generally crashes! Right click enable disable task is best way until it’s added in future versions.

[@SaschaRobitzki]

@@Three_Ways Yeah, no crashes on Windows for me when working with disabled tasks using the context menu.

[@hotsauce7124]

Are state trees the new form of state machines for character locomotion?

[@unreal_metronomus678]

No. The locomotion animation is the state machine, this is an alternative for the behavior tree. To control ai, but it is not limited to this either. You can also control other game logic with the state tree.

[@hotsauce7124]

@@unreal_metronomus678 Thank you I did not know this. Is there a tutorial describing how to create many different locomotions and switching weapons? For example, walking with a pistol uses a certain body animation with the arms stretched out and walks with short steps. Then switch to a rifle with the arms tucked in and the legs walk with longer steps, then switch to a sword with the right hand is behind the torso and the center of gravity of the body is lower? I ask because a lot of KZbin tutorials only cover one weapon and locomotoin. The other KZbin tutorials that cover multiple forms of locomotion do non seem to work.

[@unreal_metronomus678]

@@hotsauce7124 Yes, there are quite a lot of youtube videos about this. If you´re using UE 5.4, then search for motion matching, chooser and Dynamic Additive Layering. This guys has a series about how to set up different weapon animations kzbin.info/www/bejne/mpDTYoqem7Wqa6M , but it is quite advanced. There are also easier videos on how to seperate the top / bottom part of the body for different animation.

[@hotsauce7124]

@@unreal_metronomus678 Thank you, I will try this guy's tutorials. Thank you very much.

[@AetherMomon]

As of now the answer is no. But who knows they might make the animation system use state tree in the future one day. State Tree is Unreal Engine's implementation of a Finite State Machine (FSM). If you don't know what a Finite State Machine is, it is a mathematical model that describes a system with a limited number of states and transitions between them. The animation blueprint's graph also uses a finite state machine model but it is implemented in a different way and is specifically made for animations. But, technically since they both use the FSM model it should be possible to do animation stuff with State Tree as well. It's just not setup for it like ABP is so it'll be more limited in what it can do because of that. State Tree can also be used for almost anything the FSM model can be used for, like for example: Quest System, Dialogue System, Attack Combo System, AI behavior, and anything else that could benefit from the Finite State Machine model.