Pooyan#

../../../_images/pooyan.gif

This environment is part of the Atari environments. Please read that page first for general information.

Action Space

Discrete(6)

Observation Shape

(220, 160, 3)

Observation High

255

Observation Low

0

Import

gymnasium.make("ALE/Pooyan-v5")

For more Pooyan variants with different observation and action spaces, see the variants section.

Description#

You are a mother pig protecting her piglets (Pooyans) from wolves. In the first scene, you can move up and down a rope. Try to shoot the worker’s balloons, while guarding yourself from attacks. If the wolves reach the ground safely they will get behind and try to eat you. In the second scene, the wolves try to float up. You have to try and stop them using arrows and bait. You die if a wolf eats you, or a stone or rock hits you.

For a more detailed documentation, see the AtariAge page

Actions#

Pooyan has the action space Discrete(6) with the table below lists the meaning of each action’s meanings. As Pooyan uses a reduced set of actions for v0, v4 and v5 versions of the environment. To enable all 18 possible actions that can be performed on an Atari 2600, specify full_action_space=True during initialization or by passing full_action_space=True to gymnasium.make.

Value

Meaning

Value

Meaning

Value

Meaning

0

NOOP

1

FIRE

2

UP

3

DOWN

4

UPFIRE

5

DOWNFIRE

Observations#

Atari environment have two possible observation types, the observation space is listed below. See variants section for the type of observation used by each environment id.

  • obs_type="rgb" -> observation_space=Box(0, 255, (210, 160, 3), np.uint8)

  • obs_type="ram" -> observation_space=Box(0, 255, (128,), np.uint8)

Additionally, obs_type="grayscale" cause the environment return a grayscale version of the rgb array for observations with the observation space being Box(0, 255, (210, 160), np.uint8)

Rewards#

If you hit a balloon, wolf or stone with an arrow you score points. For a more detailed documentation, see the AtariAge page.

Variants#

Pooyan has the following variants of the environment id which have the following differences in observation, the number of frame-skips and the repeat action probability.

Env-id

obs_type=

frameskip=

repeat_action_probability=

Pooyan-v0

"rgb"

(2, 5)

0.25

Pooyan-ram-v0

"ram"

(2, 5)

0.25

Pooyan-ramDeterministic-v0

"ram"

4

0.25

Pooyan-ramNoFrameskip-v0

"ram"

1

0.25

PooyanDeterministic-v0

"rgb"

4

0.25

PooyanNoFrameskip-v0

"rgb"

1

0.25

Pooyan-v4

"rgb"

(2, 5)

0.0

Pooyan-ram-v4

"ram"

(2, 5)

0.0

Pooyan-ramDeterministic-v4

"ram"

4

0.0

Pooyan-ramNoFrameskip-v4

"ram"

1

0.0

PooyanDeterministic-v4

"rgb"

4

0.0

PooyanNoFrameskip-v4

"rgb"

1

0.0

ALE/Pooyan-v5

"rgb"

4

0.25

ALE/Pooyan-ram-v5

"ram"

4

0.25

Difficulty and modes#

It is possible to specify various flavors of the environment via the keyword arguments difficulty and mode. A flavor is a combination of a game mode and a difficulty setting. The table below lists the possible difficulty and mode values along with the default values.

Available Modes

Default Mode

Available Difficulties

Default Difficulty

[10, 30, 50, 70]

10

[0]

0

Version History#

A thorough discussion of the intricate differences between the versions and configurations can be found in the general article on Atari environments.

  • v5: Stickiness was added back and stochastic frameskipping was removed. The environments are now in the “ALE” namespace.

  • v4: Stickiness of actions was removed

  • v0: Initial versions release