Procgen

The Procgen backend adapts the procgen.ProcgenEnv vector API to TorchWM’s single-environment image interface for procedurally generated benchmark games such as CoinRun, Maze, Heist, and StarPilot.

Install

Procgen is an optional dependency:

pip install torchwm[procgen]

You can also install it directly with pip install procgen when working from a source checkout.

Main APIs

from world_models.envs.procgen_env import make_procgen_env, list_procgen_envs

env = make_procgen_env("coinrun", seed=0, size=(64, 64))
obs = env.reset()
print(obs["image"].shape)  # (3, 64, 64)

The factory accepts Procgen shorthand names and Gym-style ids:

make_procgen_env("coinrun")
make_procgen_env("procgen-coinrun-v0")
make_procgen_env("procgen:procgen-coinrun-v0")

Use list_procgen_envs() to inspect the supported game names.

Dreamer configuration

from world_models.configs import DreamerConfig

cfg = DreamerConfig()
cfg.env_backend = "procgen"
cfg.env = "coinrun"
cfg.image_size = 64
cfg.procgen_distribution_mode = "easy"
cfg.procgen_num_levels = 0      # 0 means unlimited levels in Procgen
cfg.procgen_start_level = None  # defaults to cfg.seed

env_backend may be either "procgen" or "coinrun". Dreamer applies the same ActionRepeat, NormalizeActions, and TimeLimit wrapper stack used by other online environment backends.

Observations and actions

ProcgenImageEnv unwraps the leading vector dimension from ProcgenEnv(num_envs=1) and returns:

{"image": uint8 array with shape (3, H, W)}

Procgen actions are discrete. For consistency with TorchWM’s other discrete image adapters, the wrapper exposes a continuous one-hot-like action space with shape (n,) and values in [-1, 1]. The selected action is the index of the largest value in the model action vector.

Example script

TorchWM includes a compact Dreamer example for Procgen environments:

python examples/run_dreamer_procgen.py --env coinrun --total-steps 2000
python examples/run_dreamer_procgen.py --list-envs

Available games

TorchWM recognizes the standard Procgen games: bigfish, bossfight, caveflyer, chaser, climber, coinrun, dodgeball, fruitbot, heist, jumper, leaper, maze, miner, ninja, plunder, and starpilot.