def find_path_astar(world_map: List[str],
src: Point,
dst: Point,
impassable: Optional[Union[str, Character]] = None,
within: int = 0):
if impassable is None:
impassable = ''
visited = [[VisitState() for x in range(len(world_map[0]))]
for y in range(len(world_map))]
visit(visited, src)
fringe: PriorityQueue[Tuple[int, Point]] = PriorityQueue()
fringe.put((0, src))
while not fringe.empty():
(_, pos) = fringe.get()
if pdist(pos, dst) <= within:
break
succs = successors(world_map, pos, impassable)
for succ in succs:
if not visited[succ.y][succ.x].visited:
visit(visited, succ, pos)
hcost = visited[succ.y][succ.x].cost + \
pdist(succ, dst)
fringe.put((hcost, succ))
if pdist(pos, dst) <= within:
return reconstruct_path(visited, src, pos)
else:
return None
def test_pdist(self):
p1 = Point(1, 2)
p2 = Point(4, 6)
assert pdist(p1, p2) == 5
p1 = Point(8, 3)
p2 = Point(7, 4)
assert pdist(p1, p2) == pytest.approx(math.sqrt(2))
def visit(visited: List[List[VisitState]],
pos: Point,
parent: Optional[Point] = None):
visited[pos.y][pos.x] = VisitState(True, 0, parent)
if parent is not None:
visited[pos.y][pos.x].cost = visited[parent.y][parent.x].cost + \
pdist(parent, pos)
def visit(visited, pos, parent=None):
visited[pos.y][pos.x] = {}
visited[pos.y][pos.x]['cost'] = 0
visited[pos.y][pos.x]['parent'] = parent
if parent is not None:
visited[pos.y][pos.x]['cost'] = visited[parent.y][parent.x]['cost'] + \
pdist(parent, pos)
def find_path_astar(world, src, dst, impassable=None, within=0):
if impassable is None:
impassable = ''
visited = [[False for x in range(world.WIDTH_TILES)]
for y in range(world.HEIGHT_TILES)]
visit(visited, src)
fringe = PriorityQueue()
fringe.put((0, src))
while not fringe.empty():
(_priority, pos) = fringe.get()
if pdist(pos, dst) <= within:
break
succs = successors(world, pos, impassable)
for succ in succs:
if not visited[succ.y][succ.x]:
visit(visited, succ, pos)
hcost = visited[succ.y][succ.x]['cost'] + \
pdist(succ, dst)
fringe.put((hcost, succ))
if pdist(pos, dst) <= within:
return reconstruct_path(visited, src, pos)
else:
return None
def tick(self):
# If we're moving in a cardinal direction, face that way
if self.new_pos.x != self.world.squirrel.pos.x \
and self.new_pos.y == self.world.squirrel.pos.y:
self.world.squirrel.facing = Direction.LEFT \
if self.new_pos.x < self.world.squirrel.pos.x \
else Direction.RIGHT
elif self.new_pos.y != self.world.squirrel.pos.y \
and self.new_pos.x == self.world.squirrel.pos.x:
self.world.squirrel.facing = Direction.UP \
if self.new_pos.y < self.world.squirrel.pos.y \
else Direction.DOWN
if self.world.can_move_to(self.new_pos):
energy_cost = pdist(self.new_pos, self.world.squirrel.pos) * \
self.ENERGY_LOSS_MULTIPLIER
self.world.squirrel.set_energy(
self.world.squirrel.energy - energy_cost)
self.world.squirrel.pos = self.new_pos
else:
self.new_pos = self.world.squirrel.pos
if self.world.squirrel.energy <= 0:
self.over("You ran out of energy!")
def _within_attack_range(self):
d = pdist(self.pos, self.game.world.squirrel.pos)
return d <= Fox.ATTACK_DISTANCE \
and not self.game.world.is_tree(self.game.world.squirrel.pos)