In this post, I mentioned I was completely satisfied with the way the state machine system was working. And when you don't like something, you change it, if you can. And in programmer-land, you can always change your code. So I got to work changing the state machine system to something I find better and cleaner. I haven't yet implemented everything, but here's an outline:

1. StateMachineComponent is attached to a game object and assigned a StateMachine to work with
2. The StateMachine is started
3. Every frame, the StateMachine is ticked
   1. The current State is ticked. This is where the State acts and does something.
   2. The current state has a list of Transitions associated with it, its exit transitions.
   3. The StateMachine loops over every one of those transitions and calls its DoTransition method. This method returns a bool and a State (through an out parameter), where true means the transition should be done. All successful Transitions are collected, and then a Transition is selected to be completed by means of a priority index. After a Transition is selected, the StateMachine changes to its returned State. If no Transition is made the StateMachine just remains in the same State.
4. Every fixed frame, the StateMachine if fixed-ticked. This only fixed-ticks the current state, and doesn't process transitions.

Furthermore, every State and Transition has to its availability a set of data from different sources:

• each StateMachine asset has a ScriptableObject which holds global data.
• there's also a lot of runtime data from different sources which can be read, such as the player's data, user input or game state.

In my opinion, these reworks make this system much better and cleaner.

The Editor

Of course, a StateMachine system needs a good graphical editor. And that's exactly what I made. Using the new UI Toolkit and the UI Builder, as well as experimental GraphView component, I crafted an editor to create and connect states and set the conditions on a Transition.

That's all I have to say for today. This was a shorter post, but making refactorings and an editor isn't much to write home about. I hope next time I can make something a bit longer. 'Til then, goodbye!