I think I don't understand the match function

[acenixton]

Godot Version

4.2.1.stable

Question

I am pretty new to this and have been searching for a while but either didn’t look in the right place or didn’t know enough to abstract the stuff I found to my situation.

This is an NPC I want to make. It should wander in a small area by default, flee from the player when they enter an area around it and go towards a fish(static body 2D) the player can throw when that lands in the area.

I tried to do this with a very simple state machine, since this is my very first project and I am figuring stuff out as I go.
I think I may have misunderstood the match function, or is there something else glaringly obvious I just didn’t see/understand?

I have basic programming knowledge, just not with Godot/GD Script and am also pretty rusty.

Every help is appreciated. If this was solved somewhere else please let me know, i am kind of overwhelmed by the amount of information out there

extends CharacterBody2D
class_name Penglin

var move_direction: Vector2
var wander_time: float
var current_state = WANDER
const speed = 20

enum {WANDER, FEED, FLEE}

func _ready():
	randomize_wander()

func _process(delta):
	match current_state:
		WANDER:
			randomize_wander()
			if wander_time > 0:
				wander_time -= delta
				
			else:
				randomize_wander()
			move(delta)
		FEED:
			move(delta)
		FLEE:
			move(delta)

func move(delta):
	position = move_direction * speed * delta

func _on_awareness_zone_body_entered(body):
	if body == Player:
		current_state = FLEE
		move_direction = global_position.bounce(body.global_position)
	else:
		current_state = FEED
		move_direction = (body.global_position - position).normalized()

func _on_awareness_zone_body_exited(body):
	if body == Player:
		current_state = WANDER
	else:
		current_state = FEED
		
func randomize_wander():
	move_direction = Vector2(randf_range(-1, 1), randf_range(-1, 1)).normalized()
	wander_time = randf_range(1, 3)

[Monday]

randomize_wander() is called every frame during the WANDER state because you call it before the if statement. I guess that’s not intended.
edit: if you just want to call it once when you switch to WANDER state you should call it inside _on_awareness_zone_body_exited() when you set current_state.

And normally you have to use move_and_slide() to move a characterbody, something like this:

func move(delta):
    velocity = move_direction * speed
    move_and_slide()

[shatteredreality]

Also, this part

position = move_direction * speed * delta

sets the position to the same value each frame until move_direction is changed. Usually when you change position directly you want to add to the position. But yeah like the poster above said you should use move_and_slide.

[acenixton]

Thank you, now it at least moves.

I still seem to have done something wrong with the states, since the direction doesn’t change if the player gets close.

[Monday]

Not sure what bounce does off the top of my head but this should give you the direction away from the body (player):

move_direction = body.global_position.direction_to(global_position)

oh also, try if body is Player:

[acenixton]

Okay great, thank you so much for your help!

I finally wrapped my head around it, I think