Files
Gymnasium/gym/envs/atari/atari_env.py
2016-04-27 08:00:58 -07:00

121 lines
3.5 KiB
Python

import numpy as np
import os
import gym
from gym import error, spaces
from gym import utils
try:
import atari_py
except ImportError:
raise error.DependencyNotInstalled("{}. (HINT: you can install Atari dependencies with 'pip install gym[atari].)'")
import logging
logger = logging.getLogger(__name__)
def to_rgb(ale):
(screen_width,screen_height) = ale.getScreenDims()
arr = np.zeros((screen_height, screen_width, 4), dtype=np.uint8)
ale.getScreenRGB(arr) # says rgb but actually bgr
return arr[:,:,[2, 1, 0]].copy()
def to_ram(ale):
ram_size = ale.getRAMSize()
ram = np.zeros((ram_size),dtype=np.uint8)
ale.getRAM(ram)
return ram
class AtariEnv(gym.Env, utils.EzPickle):
metadata = {'render.modes': ['human', 'rgb_array']}
def __init__(self, game='pong', obs_type='ram'):
utils.EzPickle.__init__(self, game, obs_type)
assert obs_type in ('ram', 'image')
game_path = atari_py.get_game_path(game)
if not os.path.exists(game_path):
raise IOError('You asked for game %s but path %s does not exist'%(game, game_path))
self.ale = atari_py.ALEInterface()
self.ale.loadROM(game_path)
self._obs_type = obs_type
self._action_set = self.ale.getMinimalActionSet()
self.viewer = None
(screen_width,screen_height) = self.ale.getScreenDims()
self.action_space = spaces.Discrete(len(self._action_set))
if self._obs_type == 'ram':
self.observation_space = spaces.Box(low=np.zeros(128), high=np.zeros(128)+255)
elif self._obs_type == 'image':
self.observation_space = spaces.Box(low=0, high=255, shape=(screen_height, screen_width, 3))
else:
raise error.Error('Unrecognized observation type: {}'.format(self._obs_type))
def _step(self, a):
reward = 0.0
action = self._action_set[a]
num_steps = np.random.randint(2, 5)
for _ in xrange(num_steps):
reward += self.ale.act(action)
ob = self._get_obs()
return ob, reward, self.ale.game_over(), {}
def _get_image(self):
return to_rgb(self.ale)
def _get_ram(self):
return to_ram(self.ale)
@property
def _n_actions(self):
return len(self._action_set)
def _get_obs(self):
if self._obs_type == 'ram':
return self._get_ram()
elif self._obs_type == 'image':
img = self._get_image()
return img
# return: (states, observations)
def _reset(self):
self.ale.reset_game()
return self._get_obs()
def _render(self, mode='human', close=False):
if close:
if self.viewer is not None:
self.viewer.close()
return
img = self._get_image()
if mode == 'rgb_array':
return img
elif mode is 'human':
from gym.envs.classic_control import rendering
if self.viewer is None:
self.viewer = rendering.SimpleImageViewer()
self.viewer.imshow(img)
def get_action_meanings(self):
return [ACTION_MEANING[i] for i in self._action_set]
ACTION_MEANING = {
0 : "NOOP",
1 : "FIRE",
2 : "UP",
3 : "RIGHT",
4 : "LEFT",
5 : "DOWN",
6 : "UPRIGHT",
7 : "UPLEFT",
8 : "DOWNRIGHT",
9 : "DOWNLEFT",
10 : "UPFIRE",
11 : "RIGHTFIRE",
12 : "LEFTFIRE",
13 : "DOWNFIRE",
14 : "UPRIGHTFIRE",
15 : "UPLEFTFIRE",
16 : "DOWNRIGHTFIRE",
17 : "DOWNLEFTFIRE",
}