ScreenShake.gd

extends Node

const TRANS = Tween.TRANS_SINE
const EASE = Tween.EASE_IN_OUT

var amplitude = 0

onready var camera = get_parent()

func start(duration=0.2, frequency=15, amplitude=16):
	self.amplitude = amplitude
	$Duration.wait_time = duration
	$Frequency.wait_time = 1 / float(frequency)
	$Duration.start()
	$Frequency.start()
	
	_new_shake()

func _new_shake():
	var rand = Vector2()
	rand.x = rand_range(-amplitude, amplitude)
	rand.y = rand_range(-amplitude, amplitude)
	
	$ShakeTween.interpolate_property(camera, "offset", camera.offset, rand, $Frequency.wait_time, TRANS, EASE)
	$ShakeTween.start()

func _reset():
	$ShakeTween.interpolate_property(camera, "offset", camera.offset, Vector2(), $Frequency.wait_time, TRANS, EASE)
	$ShakeTween.start()


func _on_Frequency_timeout():
	_new_shake()


func _on_Duration_timeout():
	_reset()
	$Frequency.stop()


func _on_Player_damage_taken(damage):
	start(0.2, 15, damage / 2.5)