Updated damage signal to player.

player.gd

@@ -2,6 +2,9 @@ extends Area2D
 
 signal died
 signal shield_changed
+signal damage_taken
+
+var shader_active = false
 
 @onready var screensize = get_viewport_rect().size
 @export var max_shield = 10
@@ -63,3 +66,13 @@ func _on_area_entered(area):
     if area.is_in_group("enemies"):
         area.explode()
         shield -= max_shield / 2
+    if area.is_in_group("enemy_bullets"):
+        damage_taken.emit()
+
+
+func _on_damage_taken() -> void:
+  shader_active = true
+  $Ship.material.set_shader_parameter("toggle", 1.0)
+  await get_tree().create_timer(1).timeout
+  shader_active = false
+  $Ship.material.set_shader_parameter("toggle", 0.0)