def __init__(self, args):
"""
Creates an object from which new environments can be created
:param args:
"""
from atari_emulator import AtariEmulator
from ale_py import ALEInterface
filename = args.rom_path + "/" + args.game + ".bin"
ale_int = ALEInterface()
ale_int.loadROM(str.encode(filename))
self.num_actions = len(ale_int.getMinimalActionSet())
self.create_environment = lambda i: AtariEmulator(i, args)
class AtariEmulator(BaseEnvironment):
def __init__(self, actor_id, args):
self.ale = ALEInterface()
self.ale.setInt(b"random_seed", args.random_seed * (actor_id + 1))
# For fuller control on explicit action repeat (>= ALE 0.5.0)
self.ale.setFloat(b"repeat_action_probability", 0.0)
# Disable frame_skip and color_averaging
# See: http://is.gd/tYzVpj
self.ale.setInt(b"frame_skip", 1)
self.ale.setBool(b"color_averaging", False)
full_rom_path = args.rom_path + "/" + args.game + ".bin"
self.ale.loadROM(str.encode(full_rom_path))
self.legal_actions = self.ale.getMinimalActionSet()
self.screen_width, self.screen_height = self.ale.getScreenDims()
self.lives = self.ale.lives()
self.random_start = args.random_start
self.single_life_episodes = args.single_life_episodes
self.call_on_new_frame = args.visualize
# Processed historcal frames that will be fed in to the network
# (i.e., four 84x84 images)
self.observation_pool = ObservationPool(
np.zeros((IMG_SIZE_X, IMG_SIZE_Y, NR_IMAGES), dtype=np.uint8))
self.rgb_screen = np.zeros((self.screen_height, self.screen_width, 3),
dtype=np.uint8)
self.gray_screen = np.zeros((self.screen_height, self.screen_width, 1),
dtype=np.uint8)
self.frame_pool = FramePool(
np.empty((FRAMES_IN_POOL, self.screen_height, self.screen_width),
dtype=np.uint8), self.__process_frame_pool)
def get_legal_actions(self):
return self.legal_actions
def __get_screen_image(self):
"""
Get the current frame luminance
:return: the current frame
"""
self.ale.getScreenGrayscale(self.gray_screen)
if self.call_on_new_frame:
self.ale.getScreenRGB(self.rgb_screen)
self.on_new_frame(self.rgb_screen)
return np.squeeze(self.gray_screen)
def get_rgb_screen(self):
self.ale.getScreenRGB(self.rgb_screen)
return self.rgb_screen
def on_new_frame(self, frame):
pass
def __new_game(self):
""" Restart game """
self.ale.reset_game()
self.lives = self.ale.lives()
if self.random_start:
wait = random.randint(0, MAX_START_WAIT)
for _ in range(wait):
self.ale.act(self.legal_actions[0])
def __process_frame_pool(self, frame_pool):
""" Preprocess frame pool """
img = np.amax(frame_pool, axis=0)
img = imresize(img, (IMG_SIZE_X, IMG_SIZE_Y), interp='nearest')
img = img.astype(np.uint8)
return img
def __action_repeat(self, a, times=ACTION_REPEAT):
""" Repeat action and grab screen into frame pool """
reward = 0
for i in range(times - FRAMES_IN_POOL):
reward += self.ale.act(self.legal_actions[a])
# Only need to add the last FRAMES_IN_POOL frames to the frame pool
for i in range(FRAMES_IN_POOL):
reward += self.ale.act(self.legal_actions[a])
self.frame_pool.new_frame(self.__get_screen_image())
return reward
def get_initial_state(self):
""" Get the initial state """
self.__new_game()
for step in range(NR_IMAGES):
_ = self.__action_repeat(0)
self.observation_pool.new_observation(
self.frame_pool.get_processed_frame())
if self.__is_terminal():
raise Exception('This should never happen.')
return self.observation_pool.get_pooled_observations()
def next(self, action):
""" Get the next state, reward, and game over signal """
reward = self.__action_repeat(np.argmax(action))
self.observation_pool.new_observation(
self.frame_pool.get_processed_frame())
terminal = self.__is_terminal()
self.lives = self.ale.lives()
observation = self.observation_pool.get_pooled_observations()
return observation, reward, terminal, self.lives
def save_frame(self, frame):
pass
def __is_terminal(self):
if self.single_life_episodes:
return self.__is_over() or (self.lives > self.ale.lives())
else:
return self.__is_over()
def __is_over(self):
return self.ale.game_over()
def get_noop(self):
return [1.0, 0.0]