Minigrid 2.4.0 Release Notes

In this release, we added new procedurally generated environments using the wave function collapse environment, the original BabyAI bot, and dynamically determined highlighting in RGBImgObsWrapper.

New Features

• Added procedural generation of environments using the Wave Function Collapse algorithm (adapted from this python implementation). By @jysdoran in https://github.com/Farama-Foundation/Minigrid/pull/371
• Changes the observation method of RGBImgObsWrapper such that the agent field-of-view (FOV) highlight is rendered only when the underlying environment has this enabled with the highlight bool, by default is True. By @thesofakillers in https://github.com/Farama-Foundation/Minigrid/pull/388
• Added the BabyAI bot from the original BabyAI repo: https://github.com/mila-iqia/babyai/blob/master/babyai/bot.py This bot can be used to generate expert demonstrations in all BabyAI environments. By @thesofakillers in https://github.com/Farama-Foundation/Minigrid/pull/381

Contributors

This release includes contributions from @ thesofakillers, @pseudo-rnd-thoughts, @BolunDai0216, @mansicer, @JupiLogy, @AdamJelley, @timoklein, @jysdoran, @mschweizer, and @Camel-light.

Minigrid 2.3.1 Release Notes

This release includes two new features:

• Added a new wrapper that prevents death in states like obstacles or lava, and gives an optional negative reward instead by @sparisi in #374
• Added a tutorial on how to train RL agent on Minigrid environments by @BolunDai0216 in #379

Contributors

This release includes contributions from: @mgoulao, @ertsiger, @BolunDai0216, @sparisi, @elliottower.

Minigrid 2.3.0 Release notes

New release with a couple of small changes that shouldn't affect users along with a new tutorial and python 3.11 support. Let us know if anything new breaks

Breaking changes

• Fix unintended observation space "image" size change in DictObservationWrapper by @jbloomAus in https://github.com/Farama-Foundation/Minigrid/pull/345
• Fix assertion error message in Grid.set() by @drmeerkat in https://github.com/Farama-Foundation/Minigrid/pull/347

New Features

• Added Tutorial for Environment Creation by @BolunDai0216 in https://github.com/Farama-Foundation/Minigrid/pull/348
• Added a stochastic action wrapper by @BolunDai0216 in https://github.com/Farama-Foundation/Minigrid/pull/355
• Adds python 3.11 support and updates pygame to 2.4.0 by @pseudo-rnd-thoughts in https://github.com/Farama-Foundation/Minigrid/pull/361

Documentation changes

• Update home page to use new style, add view code sphinx extension, update copyright and improve SEO by @mgoulao in https://github.com/Farama-Foundation/Minigrid/pull/352
• Adds DEIR: Efficient and Robust Exploration through Discriminative-Model-Based Episodic Intrinsic Rewards (U-Tokyo, Google Brain, IJCAI 2023) in publications by @alpc104 in https://github.com/Farama-Foundation/Minigrid/pull/350
• Adds "Minimal Value-Equivalent Partial Models for Scalable and Robust Planning in Lifelong Reinforcement Learning" by Alver and Precup, CoLLAs 2023 to publications by @alversafa in https://github.com/Farama-Foundation/Minigrid/pull/359

Full Changelog: https://github.com/Farama-Foundation/Minigrid/compare/v2.2.1...v2.3.0

Minigrid 2.2.1 Release Notes

This release is a minor bugfix:

• Change the default screen size from 1 to 640 by @BolunDai0216 in https://github.com/Farama-Foundation/Minigrid/pull/340

Minigrid 2.2.0 Release Notes

In this release, we added support for rendering using Pygame, which improves the previously Matplotlib-based rendering procedure, this is a breaking change that removes minigrid.utils.window.Window. A bug in the SymbolicObsWrapper that results in the wrong observation has been fixed. An error in the documentation regarding the reward function has been corrected. The ObstructedMaze environments are now ensured to be solvable. The class minigrid_env.MiniGridEnv.Actions is removed since it is the same as minigrid.core.actions.Actions.

Bug Fixes and Documentation Updates

• For the MiniGrid-DoorKey-6x6-v0 environment, a hidden variable determining the size was wrong at 5x5, this is updated to 6x6. https://github.com/Farama-Foundation/Minigrid/pull/322
• Since the class minigrid_env.MiniGridEnv.Actions is the same as minigrid.core.actions.Actions, to make the codebase cleaner, we have deleted the class minigrid_env.MiniGridEnv.Actions. This is a breaking change. For any code that relies on minigrid_env.MiniGridEnv.Actions, you can simply replace it with minigrid.core.actions.Actions. https://github.com/Farama-Foundation/Minigrid/pull/328
• In SymbolicObsWrapper, the grid that records the content of each tile is formatted as [x, y, item], which corresponds to [col, row, item], this causes a mismatch in the observation. This mismatch is now resolved. https://github.com/Farama-Foundation/Minigrid/pull/331
• The documentation for the rewards has previously incorrectly stated that the reward is 1 when the environment is solved, while it is actually 1 - 0.9 * (step_count / max_steps). Additionally, in GoToObjectEnv, there was an error in detecting whether the agent is next to the target. These issues have now been resolved. https://github.com/Farama-Foundation/Minigrid/pull/333
• Previously Minigrid relied on a Matplotlib-based rendering backend. We have added a Pygame-based rendering backend that is faster and more consistent with other Farama libraries. As a result, minigrid.utils.window.Window has been removed. https://github.com/Farama-Foundation/Minigrid/pull/313
• In the ObstructedMaze environments, the blocking ball placed by add_door may cover the box placed on the map by the previous add_door, causing the agent to be unable to open certain doors and complete the task. We have updated several of the ObstructedMaze environments to be always solvable and are registered as v1 versions of the environment. https://github.com/Farama-Foundation/Minigrid/pull/334

Bug Fixes and Documentation Updates

• Added Docstrings to the BabyAI environments by @BolunDai0216 in https://github.com/Farama-Foundation/Minigrid/pull/302
• Fixed entry point typo for MiniGrid-SimpleCrossingS11N5-v0 by @jbloomAus in https://github.com/Farama-Foundation/Minigrid/pull/306
• Fixed not changing view size bug in ViewSizeWrapper @jbloomAus in https://github.com/Farama-Foundation/Minigrid/pull/305

Full Changelog: https://github.com/Farama-Foundation/minigrid/compare/v2.1.0...v2.1.1

What's Changed

• Added new BabyAI level environments. @saleml
• New documentation website at https://minigrid.farama.org/ @SiddarGu @mgoulao. @jjshoots
• Update security permissions for GitHub workflows. #252 @andrewtanJS
• Refactor manual_control.py. @MathisFederico
• Fix issue with making all environments pickable #269. @MathisFederico
• Include max_steps argument in all of the environments. Fix https://github.com/Farama-Foundation/Minigrid/issues/264. @rodrigodelazcano
• Include agent's position in the SymbolicObsWrapper observation. Fix #278. @rodrigodelazcano

Type Hinting

• Add type hint to core API. @arjun-kg
• Improve type hint in MinigridEnv @micimize
• Add py.typed marker to use minigrid's type annotations in external tooling such as mypy

New Publications

• Composition Generalization in Grounded Language Learning via Induced Model Sparsity. @smspillaz

This release transitions the repository dependency from gym to gymnasium. gymnasium is a fork of OpenAI's Gym library by the maintainers, and is where future maintenance will occur going forward. gymnasium.farama.org

What's Changed

• Migration from gym to gymnasium v0.26. @rodrigodelazcano
• Package name change from gym_minigrid to minigrid. @rodrigodelazcano
• Change file structure for better comprehension. @pseudo-rnd-thoughts . The new file structure looks as follows:
  • Divide minigrid.py into sub-files for easier comprehension and keep them under core directory:
    • actions.py: class structure with the actions encodings
    • constants.py: constants in the environments such as object colors
    • grid.py: the grid class
    • mission.py: the mission space implementation
    • roomgrid.py: class for environments with rooms
    • world_object: object classes (Wall, Ball, Goal, Floor, ...)
  • New utils directory for rendering files rendering.py and window.py
• Add automatic doc generation for website, available at https://farama-foundation.github.io/MiniGrid/. @SiddarGu

Minor Changes

• Change file name minigrid.py to minigrid_env.py. Fixes issue #243 @rodrigodelazcano

Deprecated package naming (gym_minigrid -> minigrid)

The PyPi package name for this repository will be changed in future releases and integration with Gymnasium. The new name will be minigrid and installation will be done with pip install minigrid instead of pip install gym_minigrid.

This release adds a deprecation warning when importing or installing gym_minigrid.

Bug Fix

• Fix #232. Removed new_step_api=True argument in manual_control.py. Latest 1.2.0 MiniGrid release is not backward compatible with gym releases previous to v0.26. Thus every minigrid environment has a hard constraint on using new step API and the option to set the argument new_step_api=True in the environments was removed. @rodrigodelazcano