Save game when the window is closed

project/blocky_game/blocky_game.gd

@@ -1,6 +1,7 @@
 extends Node
 
 onready var _light = $DirectionalLight
+onready var _terrain = $VoxelTerrain
 
 
 func _unhandled_input(event):
@@ -11,3 +12,14 @@ func _unhandled_input(event):
 				# Toggle shadows
 				_light.shadow_enabled = not _light.shadow_enabled
 
+
+func _notification(what: int):
+	match what:
+		NOTIFICATION_WM_QUIT_REQUEST:
+			# Save game when the user closes the window
+			_save_world()
+
+
+func _save_world():
+	_terrain.save_modified_blocks()
+