Update "Grid-based Navigation with AStarGrid2D" demo for 4.1 (#914)

Update "Grid-based Navigation with AStarGrid2D" demo for 4.1

2d/navigation_astar/pathfind_astar.gd

@@ -8,18 +8,13 @@ const DRAW_COLOR = Color.WHITE
 
 # The object for pathfinding on 2D grids.
 var _astar = AStarGrid2D.new()
-var _map_rect = Rect2i()
 
 var _start_point = Vector2i()
 var _end_point = Vector2i()
 var _path = PackedVector2Array()
 
 func _ready():
-	# Let's assume that the entire map is located at non-negative coordinates.
-	var map_size = get_used_rect().end
-	_map_rect = Rect2i(Vector2i(), map_size)
-
-	_astar.size = map_size
+	_astar.region = get_used_rect()
 	_astar.cell_size = CELL_SIZE
 	_astar.offset = CELL_SIZE * 0.5
 	_astar.default_compute_heuristic = AStarGrid2D.HEURISTIC_MANHATTAN
@@ -27,8 +22,8 @@ func _ready():
 	_astar.diagonal_mode = AStarGrid2D.DIAGONAL_MODE_NEVER
 	_astar.update()
 
-	for i in map_size.x:
-		for j in map_size.y:
+	for i in range(_astar.region.position.x, _astar.region.end.x):
+		for j in range(_astar.region.position.y, _astar.region.end.y):
 			var pos = Vector2i(i, j)
 			if get_cell_source_id(0, pos) == Tile.OBSTACLE:
 				_astar.set_point_solid(pos)
@@ -52,7 +47,7 @@ func round_local_position(local_position):
 
 func is_point_walkable(local_position):
 	var map_position = local_to_map(local_position)
-	if _map_rect.has_point(map_position):
+	if _astar.is_in_boundsv(map_position):
 		return not _astar.is_point_solid(map_position)
 	return false
 

2d/navigation_astar/project.godot

@@ -14,7 +14,7 @@ config/name="Grid-based Pathfinding with AStarGrid2D"
 config/description="This is an example of using AStarGrid2D for navigation in 2D,
 complete with Steering Behaviors in order to smooth the movement out."
 run/main_scene="res://game.tscn"
-config/features=PackedStringArray("4.0")
+config/features=PackedStringArray("4.1")
 config/icon="res://icon.webp"
 config/tags=PackedStringArray("2d", "ai", "demo", "official", "tilemap")