Very simple camera shake

shake.gd

var cameraShakeIntensity = 0.0
var cameraShakeDuration = 0.0

func shake(intensity, duration):
	if intensity > cameraShakeIntensity and duration > cameraShakeDuration:
		cameraShakeIntensity = intensity
		cameraShakeDuration = duration

func _physics_process(delta):
	# Camera shake
	var camera = Game.Camera
	if camera and cameraShakeDuration > 0.0:
		cameraShakeDuration = cameraShakeDuration - delta
		if cameraShakeDuration <= 0:
			# Reset camera
			camera.offset = Vector2(0,0)
			cameraShakeIntensity = 0.0
			cameraShakeDuration = 0.0
		else:
			# Shake camera randomly
			camera.offset = Vector2(randf() * cameraShakeIntensity, randf() * cameraShakeIntensity)