An OpenAI Gym environment for Tetris on The Nintendo Entertainment System (NES) based on the nes-py emulator.
The preferred installation of gym-tetris
is from pip
:
pip install gym-tetris
You must import gym_tetris
before trying to make an environment.
This is because gym environments are registered at runtime. By default,
gym_tetris
environments use the full NES action space of 256
discrete actions. To constrain this, gym_tetris.actions
provides
an action list called MOVEMENT
(20 discrete actions) for the
nes_py.wrappers.JoypadSpace
wrapper. There is also
SIMPLE_MOVEMENT
with a reduced action space (6 actions). For exact details,
see gym_tetris/actions.py.
from nes_py.wrappers import JoypadSpace
import gym_tetris
from gym_tetris.actions import MOVEMENT
env = gym_tetris.make('TetrisA-v0')
env = JoypadSpace(env, MOVEMENT)
done = True
for step in range(5000):
if done:
state = env.reset()
state, reward, done, info = env.step(env.action_space.sample())
env.render()
env.close()
NOTE: gym_tetris.make
is just an alias to gym.make
for
convenience.
NOTE: remove calls to render
in training code for a nontrivial
speedup.
gym_tetris
features a command line interface for playing
environments using either the keyboard, or uniform random movement.
gym_tetris -e <environment ID> -m <`human` or `random`>
There are two game modes define in NES Tetris, namely, A-type and B-type. A-type is the standard endurance Tetris game and B-type is an arcade style mode where the agent must clear a certain number of lines to win. There are three potential reward streams: (1) the change in score, (2) the change in number of lines cleared, and (3) a penalty for an increase in board height. The table below defines the available environments in terms of the game mode (i.e., A-type or B-type) and the rewards applied.
Environment | Game Mode | reward score | reward lines | penalize height |
---|---|---|---|---|
TetrisA-v0 |
A-type | ✅ | ✕ | ✕ |
TetrisA-v1 |
A-type | ✕ | ✅ | ✕ |
TetrisA-v2 |
A-type | ✅ | ✕ | ✅ |
TetrisA-v3 |
A-type | ✕ | ✅ | ✅ |
TetrisB-v0 |
B-type | ✅ | ✕ | ✕ |
TetrisB-v1 |
B-type | ✕ | ✅ | ✕ |
TetrisB-v2 |
B-type | ✅ | ✕ | ✅ |
TetrisB-v3 |
B-type | ✕ | ✅ | ✅ |
info
dictionaryThe info
dictionary returned by the step
method contains the following
keys:
Key | Type | Description |
---|---|---|
current_piece |
str |
the current piece as a string |
number_of_lines |
int |
the number of cleared lines in [0, 999] |
score |
int |
the current score of the game in [0, 999999] |
next_piece |
str |
the next piece on deck as a string |
statistics |
dict |
the number of tetriminos dispatched (by type) |
board_height |
int |
the height of the board in [0, 20] |
Please cite gym-tetris
if you use it in your research.
@misc{gym-tetris,
author = {Christian Kauten},
howpublished = {GitHub},
title = {{Tetris (NES)} for {OpenAI Gym}},
URL = {https://github.com/Kautenja/gym-tetris},
year = {2019},
}
The following references contributed to the construction of this project.