bullets bullets bullets bullets

systems/bullets/bullet_behaviors/bullet_behavior.gd

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+@abstract
+class_name BulletBehavior
+extends Resource
+
+
+@export_group("Actions", "action_")
+## Delay in seconds before performing [member action_on_delay].
+@export_range(0.0, 1.0, 0.01, "or_greater", "suffix:s") var action_delay: float = 0.0
+## Performed once the bullet has existed for [member action_delay] seconds.
+@export var action_on_delay: BulletAction
+## Interval in seconds at which [member action_on_interval] is performed.
+@export_range(0.0, 1.0, 0.01, "or_greater", "suffix:s") var action_interval: float = 0.0
+## Performed every [member action_interval] seconds.
+@export var action_on_interval: BulletAction
+
+
+var _bullet_interval_cooldowns: Dictionary[Bullet, float] = {}
+
+
+## Performs behavior-specific initialization for a [Bullet].
+func init_bullet(bullet: Bullet) -> void:
+	if action_on_interval:
+		_bullet_interval_cooldowns[bullet] = action_interval
+	bullet.recycled.connect(deinit_bullet.bind(bullet), CONNECT_ONE_SHOT)
+	_init_bullet(bullet)
+
+
+## Cleans up behavior-specific state for a [Bullet].
+func deinit_bullet(bullet: Bullet) -> void:
+	_bullet_interval_cooldowns.erase(bullet)
+	_deinit_bullet(bullet)
+
+
+## Processes one tick of a [Bullet]'s movement.
+func process_bullet(bullet: Bullet, delta: float) -> void:
+	var last_time = bullet.time_elapsed
+	bullet.time_elapsed += delta
+	if last_time < action_delay and bullet.time_elapsed >= action_delay and action_on_delay:
+		action_on_delay.perform(bullet)
+	if action_on_interval:
+		_bullet_interval_cooldowns[bullet] -= delta
+		if _bullet_interval_cooldowns[bullet] <= 0.0:
+			_bullet_interval_cooldowns[bullet] += action_interval
+	_process_bullet(bullet, delta)
+
+
+## Called when a [Bullet] is spawned with this behavior in order to set up
+## behavior-specific state.
+@abstract func _init_bullet(bullet: Bullet) -> void
+
+
+## Called when a [Bullet] is recycled in order to clean up behavior-specific state.
+@abstract func _deinit_bullet(bullet: Bullet) -> void
+
+
+## Called to process a tick of a [Bullet]'s movement.
+@abstract func _process_bullet(bullet: Bullet, delta: float) -> void