Minesweeper Environment#
We provide here a Jax JIT-able implementation of the Minesweeper game.
Observation#
The observation given to the agent consists of:
-
board: jax array (int32) of shape(num_rows, num_cols): each cell contains-1if not yet explored, or otherwise the number of mines in the 8 adjacent squares. -
action_mask: jax array (bool) of shape(num_rows, num_cols): indicates which actions are valid (not yet explored squares). This can also be determined from the board which will have an entry of-1in all of these positions. -
num_mines: jax array (int32) of shape(), indicates the number of mines to locate. -
step_count: jax array (int32) of shape(): specifies how many timesteps have elapsed since environment reset.
Action#
The action space is a MultiDiscreteArray of integer values representing coordinates of the square
to explore, e.g. [3, 6] for the cell located on the third row and sixth column. If either a mined
square or an already explored square is selected, the episode terminates (the latter are termed
invalid actions).
Also, exploring a square will reveal only the contents of that square. This differs slightly from the usual implementation of the game, which automatically and recursively reveals neighbouring squares if there are no adjacent mines.
Reward#
The reward is configurable, but default to +1 for exploring a new square that does not contain a
mine, and 0 otherwise (which also terminates the episode). The episode also terminates if the
board is solved.
Registered Versions 📖#
Minesweeper-v0, the classic game on a 10x10 grid with 10 mines to locate.