def __wall_distances(self, snake_head: Point,
direction: Direction) -> np.array:
north_wall = Point(snake_head.x, 0)
west_wall = Point(0, snake_head.y)
south_wall = Point(snake_head.x, self.game.dimensions()[1])
east_wall = Point(self.game.dimensions()[0], snake_head.y)
snake_north_wall_dist = snake_head.distance(north_wall)
snake_west_wall_dist = snake_head.distance(west_wall)
snake_south_wall_dist = snake_head.distance(south_wall)
snake_east_wall_dist = snake_head.distance(east_wall)
if direction == Direction.UP:
return np.array([
snake_west_wall_dist, snake_north_wall_dist,
snake_east_wall_dist
])
if direction == Direction.RIGHT:
return np.array([
snake_north_wall_dist, snake_east_wall_dist,
snake_south_wall_dist
])
if direction == Direction.DOWN:
return np.array([
snake_east_wall_dist, snake_south_wall_dist,
snake_west_wall_dist
])
if direction == Direction.LEFT:
return np.array([
snake_south_wall_dist, snake_west_wall_dist,
snake_north_wall_dist
])
def __stop_lidar(self):
"""
Gets the snakes 8 point lidar in it's starting position.
:return:
"""
lidar_pulses = [
self.lidar_north_pulse(),
self.lidar_north_east_pulse(),
self.lidar_east_pulse(),
self.lidar_south_east_pulse(),
self.lidar_south_pulse(),
self.lidar_south_west_pulse(),
self.lidar_west_pulse(),
self.lidar_north_west_pulse()
]
lidar = np.zeros((len(lidar_pulses) * 3), dtype=np.float32)
snake_x, snake_y = self.snakeEnv.snake.head.pos(
)[0], self.snakeEnv.snake.head.pos()[1]
snake_pos = Point(snake_x, snake_y)
for i in range(len(lidar_pulses)):
lidar_pulse = lidar_pulses[i]
index = i * 3
lidar[index] = snake_pos.distance(lidar_pulse[0])
lidar[index + 1] = lidar_pulse[1]
lidar[index + 2] = lidar_pulse[2]
self.lidar_end_points = [
lidar_pulse[0] for lidar_pulse in lidar_pulses
]
return lidar
def __left_lidar(self):
"""
Gets the Snake's 5 point lidar distances when it is facing left.
Parameters:
None
Returns:
lidar - A 1D numpy array with 5 entries, one for each lidar distance.
"""
lidar_pulses = [
self.lidar_south_pulse(),
self.lidar_south_west_pulse(),
self.lidar_west_pulse(),
self.lidar_north_west_pulse(),
self.lidar_north_pulse()
]
lidar = np.zeros((len(lidar_pulses) * 3), dtype=np.float32)
snake_x, snake_y = self.snakeEnv.snake.head.pos(
)[0], self.snakeEnv.snake.head.pos()[1]
snake_pos = Point(snake_x, snake_y)
for i in range(len(lidar_pulses)):
lidar_pulse = lidar_pulses[i]
index = i * 3
lidar[index] = snake_pos.distance(lidar_pulse[0])
lidar[index + 1] = lidar_pulse[1]
lidar[index + 2] = lidar_pulse[2]
self.lidar_end_points = [
lidar_pulses[0][0], lidar_pulses[1][0], lidar_pulses[2][0],
lidar_pulses[3][0], lidar_pulses[4][0]
]
return lidar
def __get_food_distance_reward(self, previous_location: Point,
current_location: Point):
"""
:param previous_location: A type point that specifies previous location of the environment
:param current_location: A type point that specifies the current location of the environment
:return: 1 if the environment moved towards the food, 0 if the environment moved away from the food
"""
"""
food_x = self.current_food.head.xcor()
food_y = self.current_food.head.ycor()
food_point = Point(food_x, food_y)
if (previous_location.distance(food_point) > current_location.distance(food_point)):
return 1
return
"""
def normalise(x):
return 1 - (x / self.max_distance)
food_x = self.current_food.head.xcor()
food_y = self.current_food.head.ycor()
food_point = Point(food_x, food_y)
multiplier = len(
self.snake.segments) if len(self.snake.segments) > 2 else 1
return normalise(current_location.distance(food_point)) * multiplier
def distance_to_apple_percentage_tail_length_multiplier(env: SnakeEnv):
def normalise(x):
return 1 - (x / env.max_distance)
food_x = env.current_food.head.xcor()
food_y = env.current_food.head.ycor()
food_point = Point(food_x, food_y)
current_location = Point(env.snake.head.xcor(), env.snake.head.ycor())
multiplier = len(env.snake.segments) if len(env.snake.segments) > 2 else 1
return normalise(current_location.distance(food_point)) * multiplier
