Enemy script, increase bullet collision count

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1
:information_source: Attention Topic was automatically imported from the old Question2Answer platform.
:bust_in_silhouette: Asked By verbaloid

I took the default 2D platformer template and now modifying if with my graphics and sounds.
This is the enemy script, where the enemy dies after single collision with a bullet object.
It only has two states, default and STATE_DYING.
But I need an intermediary state, I guess.
The first two collisions I need it to play animation 'being_hit"
On the third and fourth collision it should play animation “being_injured”
And only on fifth collision it should play “dying”
How do I modify this script to add these things?
It uses state machines, I haven’t wrapped my novice mind around them.

Here’s the enemy script.

extends RigidBody2D

class_name Enemy

# Member variables
const WALK_SPEED = 50
const STATE_WALKING = 0
const STATE_DYING = 1

# state machine
var state = STATE_WALKING

var direction = -1
var anim = ""

onready var rc_left = $RaycastLeft
onready var rc_right = $RaycastRight

var Bullet = preload("res://player/bullet.gd")


func _die():
	queue_free()

func _pre_explode():
	#make sure nothing collides against this
	$Shape1.queue_free()
	$Shape2.queue_free()
	$Shape3.queue_free()
	
	# Stay there
	mode = MODE_STATIC
	($SoundExplode as AudioStreamPlayer2D).play()
	
func _bullet_collider(cc, s, dp):
	mode = MODE_RIGID
	state = STATE_DYING
	
	s.set_angular_velocity(sign(dp.x) * 33.0)
	set_friction(1)
	cc.disable()
	($SoundHit as AudioStreamPlayer2D).play()

func _integrate_forces(s):
	var lv = s.get_linear_velocity()
	var new_anim = anim

	if state == STATE_DYING:
		new_anim = "explode"
	elif state == STATE_WALKING:
		new_anim = "walk"
		
		var wall_side = 0.0
		
		for i in range(s.get_contact_count()):
			var cc = s.get_contact_collider_object(i)
			var dp = s.get_contact_local_normal(i)
			
			if cc:
				if cc is Bullet and not cc.disabled:
					# enqueue call
					call_deferred("_bullet_collider", cc, s, dp)
					break
			
			if dp.x > 0.9:
				wall_side = 1.0
			elif dp.x < -0.9:
				wall_side = -1.0
		
		if wall_side != 0 and wall_side != direction:
			direction = -direction
			($Sprite as Sprite).scale.x = -direction
		if direction < 0 and not rc_left.is_colliding() and rc_right.is_colliding():
			direction = -direction
			($Sprite as Sprite).scale.x = -direction
		elif direction > 0 and not rc_right.is_colliding() and rc_left.is_colliding():
			direction = -direction
			($Sprite as Sprite).scale.x = -direction
		
		lv.x = direction * WALK_SPEED
	
	if anim != new_anim:
		anim = new_anim
		($Anim as AnimationPlayer).play(anim)
	
	s.set_linear_velocity(lv)
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:bust_in_silhouette: Reply From: MitchReidNZ

You sound like you’ve got the right idea.
Maybe a couple of new states? STATE_HURT, STATE_INJURED?

Throw in a health variable after you declare your current state:

var health = 5

Then, in _bullet_collider you can decrement your health variable and update your state:

health -= 1

if health < 5:
  state = STATE_HURT
if health < 3:
  state = STATE_INJURED
if health <= 0:
  state = STATE_DYING

Finally, in _integrate_forces you can check for your two new states and set new_anim appropriately.

You might also want to move out your movement logic from STATE_WALKING so that it’s applied to _WALKING,_HURT, and _INJURED. Or maybe you want hurt / injured to move differently? That’s up to you.

Edits: Fixing up formatting, so I don’t get spontaneous italics.