All language subtitles for 3. FSM Example in Godot

In this example, we will have three different states: the idle state, the move state, and the fire
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state.
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These are basically just some scripts with a little code.
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They're nothing special.
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But of course you can imagine that this is an AI because it can be
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an actual AI here. Every state will be connected with each other and will trigger transitions when
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specific conditions are met.
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Let's configure the finite state machine example first.
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This will be the main screen which currently has two buttons.
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Is moving button and is firing button.
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Basically what they'll do is have a special signal.
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That this called in this debug script and this debug script.
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What it does it has two signals from is moving button and is firing button and it was set up two states
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and will set up inside the custom finite state machine that we created. The database with the is_moving or
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is_firing and will also reflect this in the button text itself.
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Also, we need to show the current state in a label.
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So if we go back, the current state will be visible in this label to be able to properly debug it.
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Now let's go back a little to the idle state because we need to make some changes here because we will
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have some connections between idle state, move state and fire state.
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If the finite state machine...
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By the way, in this implementation, in the check conditions, we will create the transitions for various
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states.
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So we need to get the value and is moving.
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Be mindful that this value is actually set in this debug script.
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So is_moving.
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It needs to be the same.
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I can just copy paste it to make sure is the same.
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Otherwise what I recommend you to do is create a globals file.
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You can do that by using a singleton in Godot and basically create a variable that has this string
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and use that variable instead to remove the hardcoding part.
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Because by just missing one character here, then it won't work anymore.
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This is a pro tip basically.
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So get value is_moving.
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And of course this is true.
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Then we need to change the state to the move state.
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How is the move state called?
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Well, it's actually the same name as here.
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And, if you remember from the implementation, we get every state from the children.
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We create the dictionary where we keep our values.
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So based on the name actually written here, we actually get the state as well.
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So this is how we go to the move state.
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And now, of course, we don't want to continue this because we already changed the finite state machine
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to the move state.
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But if it was not moving, then it might be a possibility for it to be shooting or is_firing.
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And if that's the case, then we need to change it.
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FireState.
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And by changing to the fire state, then of course, this is a new state.
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And in the move state as well as in the fire state, we see very similar code, but we just check for
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the values in the other direction.
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Just be mindful that some changes here are really important.
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So as you can see in the move state, it's a little different.
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The if statements are embedded as well as in the fire state.
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This is important to prevent unusual transitions in the state machine.
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Before we can run this, I need to set up the entry state in the custom finite state machine.
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And of course I want it to be IdleState.
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So the entry state will be running. By the way, if we run the state machine about this, it'll crash.
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So make sure to actually put this here.
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If we run this, then of course, the current state is idle state and we entered the idle state.
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If the enemy is moving, then the variable is_moving will be set up.
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In this case, I'm just going to set it up by pressing the button.
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But as you can see, we exited the idle state and we entered the move state.
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And the current state is of course, the move state.
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If I put in the firing.
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As you can see here, the moves state is still going because of the way conditions are created.
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So it will go to firing only if I disable is_moving.
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And basically what it does here, it goes back to idle and then checks: is firing online?
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And as you can see here in the moving so exited move state. Entered idle state exited idle state
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and entered fire state.
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And this is how we end up in the fire state.
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Be careful how you create your transitions because this will affect your whole logic of the finite state
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machine.
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Basically, this is all about finite state machines.
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Now let's find out in the next module how to get an AI from a position A to a position B using pathfinding.