def render(self, mode='human', close=False):
if close:
return
if mode == 'human':
if not hasattr(self, "gui"):
obj_pos = []
for ship in self.state.ships:
pos = ship.pos
obj_pos.append(self.grid.get_index(pos))
for i in range(ship.length):
pos += Compass.get_coord(ship.direction)
obj_pos.append(self.grid.get_index(pos))
self.gui = ShipGui(board_size=self.grid.get_size, obj_pos=obj_pos)
if self.t > 0:
msg = "A: " + str(self.grid.get_coord(self.last_action)) + "T: " + str(self.t) + "Rw :" + str(
self.tot_rw)
self.gui.render(state=self.last_action, msg=msg)
class BattleShipEnv(Env):
metadata = {"render.modes": ["human", "ansi"]}
def __init__(self, board_size=(5, 5), ship_sizes=[5, 4, 3, 3, 2]):
self.grid = BattleGrid(board_size)
self.action_space = Discrete(self.grid.n_tiles)
self.observation_space = Discrete(len(Obs))
self.num_obs = 2
self._reward_range = self.action_space.n / 4.
self._discount = 1.
self.ship_sizes = ship_sizes
self.total_remaining = sum(self.ship_sizes)
def seed(self, seed=None):
np.random.seed(seed)
def _compute_prob(self, action, next_state, ob):
action_pos = self.grid.get_coord(action)
cell = self.grid[action_pos]
if ob == Obs.NULL.value and cell.visited:
return 1
elif ob == Obs.HIT.value and cell.occupied:
return 1
else:
return int(ob == Obs.NULL.value)
def step(self, action):
assert self.done is False
assert self.action_space.contains(action)
assert self.total_remaining > 0
self.last_action = action
self.t += 1
action_pos = self.grid.get_coord(action)
# cell = self.grid.get_value(action_pos)
cell = self.grid[action_pos]
reward = 0
if cell.visited:
reward -= 10
obs = Obs.NULL.value
else:
if cell.occupied:
reward -= 1
obs = 1
self.state.total_remaining -= 1
for d in range(4, 8):
if self.grid[action_pos + Compass.get_coord(d)]:
self.grid[action_pos +
Compass.get_coord(d)].diagonal = False
else:
reward -= 1
obs = Obs.NULL.value
cell.visited = True
if self.state.total_remaining == 0:
reward += self.grid.n_tiles
self.done = True
self.tot_rw += reward
return obs, reward, self.done, {"state": self.state}
def _set_state(self, state):
self.reset()
self.state = state
def close(self):
return
def reset(self):
self.done = False
self.tot_rw = 0
self.t = 0
self.last_action = -1
self.state = self._get_init_state()
return Obs.NULL.value
def render(self, mode='human', close=False):
if close:
return
if mode == 'human':
if not hasattr(self, "gui"):
obj_pos = []
for ship in self.state.ships:
pos = ship.pos
obj_pos.append(self.grid.get_index(pos))
for i in range(ship.length):
pos += Compass.get_coord(ship.direction)
obj_pos.append(self.grid.get_index(pos))
self.gui = ShipGui(board_size=self.grid.get_size,
obj_pos=obj_pos)
if self.t > 0:
msg = "A: " + str(self.grid.get_coord(
self.last_action)) + "T: " + str(self.t) + "Rw :" + str(
self.tot_rw)
self.gui.render(state=self.last_action, msg=msg)
def _generate_legal(self):
# assert self.state.total_remaining > 0
actions = []
for action in range(self.action_space.n):
action_pos = self.grid.get_coord(action)
if not self.grid[action_pos].visited:
actions.append(action)
# assert len(actions) > 0
return actions
def _get_init_state(self):
bsstate = ShipState()
self.grid.build_board()
for length in self.ship_sizes:
# num_ships = 1
# for idx in range(num_ships):
while True: # add one ship of each kind
ship = Ship(coord=self.grid.sample(), length=length)
if not self.collision(ship, self.grid, bsstate):
break
self.mark_ship(ship, self.grid, bsstate)
bsstate.ships.append(ship)
return bsstate
@staticmethod
def mark_ship(ship, grid, state):
pos = ship.pos # .copy()
for i in range(ship.length + 1):
cell = grid[pos]
assert not cell.occupied
cell.occupied = True
if not cell.visited:
state.total_remaining += 1
pos += Compass.get_coord(ship.direction)
@staticmethod
def collision(ship, grid, state):
pos = ship.pos # .copy()
for i in range(ship.length):
if not grid.is_inside(pos + Compass.get_coord(ship.direction)):
return True
# cell = grid.get_value(pos)
cell = grid[pos]
if cell.occupied:
return True
for adj in range(8):
coord = pos + Compass.get_coord(adj)
if grid.is_inside(coord) and grid[coord].occupied:
return True
pos += Compass.get_coord(ship.direction)
return False