GridWorld

class magent2.gridworld.GridWorld(config: Config, **kwargs)

The main MAgent2 class for implementing environments. MAgent2 environments are square Gridworlds wherein each coordinate may contain an agent, a wall, or nothing.

The class attributes are not accessible directly due to them living in the underlying C++ code. Thus, there are get/set methods for retrieving and manipulating their values.

Methods

magent2.gridworld.GridWorld.new_group(self, name: str) → c_int

Registers a new group of agents into environment.

Parameters:

name (str) – Name of the group.

Returns:

handle (ctypes.c_int32) – A handle to reference the group in future gets and sets.

magent2.gridworld.GridWorld.add_agents(self, handle: c_int, method: str, **kwargs)

Adds agents to environment.

Parameters:

  • handle (ctypes.c_int32) – The handle of the group to which to add the agents.

  • method (str) – Can be ‘random’ or ‘custom’. If method is ‘random’, then kwargs[“n”] is a int. If method is ‘custom’, then kwargs[“pos”] is a list of coordination.

``` # add 1000 walls randomly >>> env.add_agents(handle, method=”random”, n=1000)

# add 3 agents to (1,2), (4,5) and (9, 8) in map >>> env.add_agents(handle, method=”custom”, pos=[(1,2), (4,5), (9,8)]) ```

magent2.gridworld.GridWorld.add_walls(self, method: str, **kwargs)

Adds walls to the environment.

Parameters:

method (str) – Can be ‘random’ or ‘custom’. If method is ‘random’, then kwargs[“n”] is an int. If method is ‘custom’, then kwargs[“pos”] is a list of coordination

``` # add 1000 walls randomly >>> env.add_walls(method=”random”, n=1000)

# add 3 walls to (1,2), (4,5) and (9, 8) in map >>> env.add_walls(method=”custom”, pos=[(1,2), (4,5), (9,8)]) ```

magent2.gridworld.GridWorld.reset(self)

Resets the environment to an initial internal state.

magent2.gridworld.GridWorld.set_action(self, handle: c_int, actions: ndarray)

Set actions for whole group.

Parameters:

  • handle (ctypes.c_int32) – Group handle.

  • actions (np.ndarray) – Array of actions, 1 per agent. The dtype must be int32.

magent2.gridworld.GridWorld.step(self)

Runs one timestep of the environment using the agents’ actions.

Returns:

done (bool) – Flag indicating whether the game is done or not.

magent2.gridworld.GridWorld.render(self)

Renders a step.

magent2.gridworld.GridWorld.set_seed(self, seed: int)

Set random seed of the engine.

Parameters:

seed (int) – Seed value.

magent2.gridworld.GridWorld.set_render_dir(self, name: str)

Sets the directory to save render file.

Parameters:

name (str) – Name of render directory.

magent2.gridworld.GridWorld.clear_dead(self)

Clears dead agents in the engine. Must be called after step().

magent2.gridworld.GridWorld.get_handles(self) → List[c_int]

Returns all group handles in the environment.

Returns:

handles (List[ctypes.c_int32]) – All group handles in the environment.

magent2.gridworld.GridWorld.get_observation(self, handle: c_int) → Tuple[ndarray, ndarray]

Returns the observation for each agent in a group.

Parameters:

handle (ctypes.c_int32) – Group handle.

Returns:

obs (Tuple[np.ndarray, np.ndarray]) – (views, features) Views is a numpy array whose shape is n * view_width * view_height * n_channel. Features is a numpy array whose shape is n * feature_size. For agent i, (views[i], features[i]) is its observation at this step.

magent2.gridworld.GridWorld.get_reward(self, handle: c_int) → ndarray

Returns the rewards for all agents in a group.

Parameters:

handle (ctypes.c_int32) – Group handle.

Returns:

rewards (np.ndarray[float32]) – Rewards for all agents in the group.

magent2.gridworld.GridWorld.get_action_space(self, handle: c_int) → Tuple[int]

Returns the action space for a group.

Parameters:

handle (ctypes.c_int32) – Group handle.

Returns:

action_space (Tuple[int]) – Action space for the group.

magent2.gridworld.GridWorld.get_view_space(self, handle: c_int) → Tuple[int, int, int]

Returns the view space for a group.

Parameters:

handle (ctypes.c_int32) – Group handle.

Returns:

view_space (Tuple[int, int, int]) – View space for the group.

magent2.gridworld.GridWorld.get_feature_space(self, handle: c_int) → Tuple[int]

Returns the feature space for a group.

Parameters:

handle (ctypes.c_int32) – Group handle.

Returns:

feature_space (Tuple[int]) – Feature space for the group.

magent2.gridworld.GridWorld.get_num(self, handle: c_int) → int

Returns the number of agents in a group.

Parameters:

handle (ctypes.c_int32) – Group handle.

Returns:

num (int) – Number of agents in the group.

magent2.gridworld.GridWorld.get_agent_id(self, handle: c_int) → ndarray

Returns the ids of all agents in the group.

Parameters:

handle (ctypes.c_int32) – Group handle.

Returns:

ids (np.ndarray[int32]) – Ids of all agents in the group.

magent2.gridworld.GridWorld.get_alive(self, handle: c_int) → ndarray

Returns the alive status of all agents in a group.

Parameters:

handle (ctypes.c_int32) – Group handle.

Returns:

alives (np.ndarray[bool]) – Whether the agents are alive or not.

magent2.gridworld.GridWorld.get_pos(self, handle: c_int) → ndarray

Returns the positions of all agents in a group.

Parameters:

handle (ctypes.c_int32) – Group handle.

Returns:

pos (np.ndarray[int]) – The positions of all agents in the group. The shape is (n, 2).

magent2.gridworld.GridWorld.get_view2attack(self, handle: c_int) → Tuple[int, ndarray]

Get a matrix with the same size of view_range. If element >= 0, then it is an attackable point, and the corresponding action number is the value of that element.

Parameters:

handle (ctypes.c_int32) – Group handle.

Returns:

  • attack_base (int) – Attack action base value.

  • buf (np.ndarray) – Map attack action into view.

magent2.gridworld.GridWorld.get_global_minimap(self, height: int, width: int) → ndarray

Compress global map into a minimap of given size.

Parameters:

  • height (int) – Height of minimap.

  • width (int) – Width of minimap.

Returns:

minimap (np.ndarray) – Map of shape (n_group + 1, height, width).