""" Collection of environment-specific ObservationBuilder. """ import collections from typing import Optional, List, Dict, Tuple import numpy as np from flatland.core.env import Environment from flatland.core.env_observation_builder import ObservationBuilder from flatland.core.env_prediction_builder import PredictionBuilder from flatland.core.grid.grid4_utils import get_new_position from flatland.core.grid.grid_utils import coordinate_to_position from flatland.envs.agent_utils import RailAgentStatus, EnvAgent from flatland.utils.ordered_set import OrderedSet class MyTreeObsForRailEnv(ObservationBuilder): """ TreeObsForRailEnv object. This object returns observation vectors for agents in the RailEnv environment. The information is local to each agent and exploits the graph structure of the rail network to simplify the representation of the state of the environment for each agent. For details about the features in the tree observation see the get() function. """ Node = collections.namedtuple('Node', 'dist_min_to_target ' 'target_encountered ' 'num_agents_same_direction ' 'num_agents_opposite_direction ' 'childs') tree_explored_actions_char = ['L', 'F', 'R', 'B'] def __init__(self, max_depth: int, predictor: PredictionBuilder = None): super().__init__() self.max_depth = max_depth self.observation_dim = 2 self.location_has_agent = {} self.predictor = predictor self.location_has_target = None self.switches_list = {} self.switches_neighbours_list = [] self.check_agent_descision = None def reset(self): self.location_has_target = {tuple(agent.target): 1 for agent in self.env.agents} def set_switch_and_pre_switch(self, switch_list, pre_switch_list, check_agent_descision): self.switches_list = switch_list self.switches_neighbours_list = pre_switch_list self.check_agent_descision = check_agent_descision def get_many(self, handles: Optional[List[int]] = None) -> Dict[int, Node]: """ Called whenever an observation has to be computed for the `env` environment, for each agent with handle in the `handles` list. """ if handles is None: handles = [] if self.predictor: self.max_prediction_depth = 0 self.predicted_pos = {} self.predicted_dir = {} self.predictions = self.predictor.get() if self.predictions: for t in range(self.predictor.max_depth + 1): pos_list = [] dir_list = [] for a in handles: if self.predictions[a] is None: continue pos_list.append(self.predictions[a][t][1:3]) dir_list.append(self.predictions[a][t][3]) self.predicted_pos.update({t: coordinate_to_position(self.env.width, pos_list)}) self.predicted_dir.update({t: dir_list}) self.max_prediction_depth = len(self.predicted_pos) # Update local lookup table for all agents' positions # ignore other agents not in the grid (only status active and done) self.location_has_agent = {} self.location_has_agent_direction = {} self.location_has_agent_speed = {} self.location_has_agent_malfunction = {} self.location_has_agent_ready_to_depart = {} for _agent in self.env.agents: if _agent.status in [RailAgentStatus.ACTIVE, RailAgentStatus.DONE] and \ _agent.position: self.location_has_agent[tuple(_agent.position)] = 1 self.location_has_agent_direction[tuple(_agent.position)] = _agent.direction self.location_has_agent_speed[tuple(_agent.position)] = _agent.speed_data['speed'] self.location_has_agent_malfunction[tuple(_agent.position)] = _agent.malfunction_data[ 'malfunction'] if _agent.status in [RailAgentStatus.READY_TO_DEPART] and \ _agent.initial_position: self.location_has_agent_ready_to_depart[tuple(_agent.initial_position)] = \ self.location_has_agent_ready_to_depart.get(tuple(_agent.initial_position), 0) + 1 observations = super().get_many(handles) return observations def get(self, handle: int = 0) -> Node: """ Computes the current observation for agent `handle` in env The observation vector is composed of 4 sequential parts, corresponding to data from the up to 4 possible movements in a RailEnv (up to because only a subset of possible transitions are allowed in RailEnv). The possible movements are sorted relative to the current orientation of the agent, rather than NESW as for the transitions. The order is:: [data from 'left'] + [data from 'forward'] + [data from 'right'] + [data from 'back'] Each branch data is organized as:: [root node information] + [recursive branch data from 'left'] + [... from 'forward'] + [... from 'right] + [... from 'back'] Each node information is composed of 9 features: #1: if own target lies on the explored branch the current distance from the agent in number of cells is stored. #2: if another agents target is detected the distance in number of cells from the agents current location\ is stored #3: if another agent is detected the distance in number of cells from current agent position is stored. #4: possible conflict detected tot_dist = Other agent predicts to pass along this cell at the same time as the agent, we store the \ distance in number of cells from current agent position 0 = No other agent reserve the same cell at similar time #5: if an not usable switch (for agent) is detected we store the distance. #6: This feature stores the distance in number of cells to the next branching (current node) #7: minimum distance from node to the agent's target given the direction of the agent if this path is chosen #8: agent in the same direction n = number of agents present same direction \ (possible future use: number of other agents in the same direction in this branch) 0 = no agent present same direction #9: agent in the opposite direction n = number of agents present other direction than myself (so conflict) \ (possible future use: number of other agents in other direction in this branch, ie. number of conflicts) 0 = no agent present other direction than myself #10: malfunctioning/blokcing agents n = number of time steps the oberved agent remains blocked #11: slowest observed speed of an agent in same direction 1 if no agent is observed min_fractional speed otherwise #12: number of agents ready to depart but no yet active Missing/padding nodes are filled in with -inf (truncated). Missing values in present node are filled in with +inf (truncated). In case of the root node, the values are [0, 0, 0, 0, distance from agent to target, own malfunction, own speed] In case the target node is reached, the values are [0, 0, 0, 0, 0]. """ if handle > len(self.env.agents): print("ERROR: obs _get - handle ", handle, " len(agents)", len(self.env.agents)) agent = self.env.agents[handle] # TODO: handle being treated as index if agent.status == RailAgentStatus.READY_TO_DEPART: agent_virtual_position = agent.initial_position elif agent.status == RailAgentStatus.ACTIVE: agent_virtual_position = agent.position elif agent.status == RailAgentStatus.DONE: agent_virtual_position = agent.target else: return None possible_transitions = self.env.rail.get_transitions(*agent_virtual_position, agent.direction) num_transitions = np.count_nonzero(possible_transitions) # Here information about the agent itself is stored distance_map = self.env.distance_map.get() root_node_observation = MyTreeObsForRailEnv.Node(dist_min_to_target=distance_map[ (handle, *agent_virtual_position, agent.direction)], target_encountered=0, num_agents_same_direction=0, num_agents_opposite_direction=0, childs={}) visited = OrderedSet() # Start from the current orientation, and see which transitions are available; # organize them as [left, forward, right, back], relative to the current orientation # If only one transition is possible, the tree is oriented with this transition as the forward branch. orientation = agent.direction if num_transitions == 1: orientation = np.argmax(possible_transitions) for i, branch_direction in enumerate([(orientation + i) % 4 for i in range(-1, 3)]): if possible_transitions[branch_direction]: new_cell = get_new_position(agent_virtual_position, branch_direction) branch_observation, branch_visited = \ self._explore_branch(handle, new_cell, branch_direction, 1, 1) root_node_observation.childs[self.tree_explored_actions_char[i]] = branch_observation visited |= branch_visited else: # add cells filled with infinity if no transition is possible root_node_observation.childs[self.tree_explored_actions_char[i]] = -np.inf self.env.dev_obs_dict[handle] = visited return root_node_observation def _explore_branch(self, handle, position, direction, tot_dist, depth): """ Utility function to compute tree-based observations. We walk along the branch and collect the information documented in the get() function. If there is a branching point a new node is created and each possible branch is explored. """ # [Recursive branch opened] if depth >= self.max_depth + 1: return [], [] # Continue along direction until next switch or # until no transitions are possible along the current direction (i.e., dead-ends) # We treat dead-ends as nodes, instead of going back, to avoid loops exploring = True visited = OrderedSet() agent = self.env.agents[handle] other_agent_opposite_direction = 0 other_agent_same_direction = 0 dist_min_to_target = self.env.distance_map.get()[handle, position[0], position[1], direction] last_is_dead_end = False last_is_a_decision_cell = False target_encountered = 0 cnt = 0 while exploring: dist_min_to_target = min(dist_min_to_target, self.env.distance_map.get()[handle, position[0], position[1], direction]) if agent.target == position: target_encountered = 1 new_direction_me = direction new_cell_me = position a = self.env.agent_positions[new_cell_me] if a != -1 and a != handle: opp_agent = self.env.agents[a] # look one step forward # opp_possible_transitions = self.env.rail.get_transitions(*opp_agent.position, opp_agent.direction) if opp_agent.direction != new_direction_me: # opp_possible_transitions[new_direction_me] == 0: other_agent_opposite_direction += 1 else: other_agent_same_direction += 1 # ############################# # ############################# if (position[0], position[1], direction) in visited: break visited.add((position[0], position[1], direction)) # If the target node is encountered, pick that as node. Also, no further branching is possible. if np.array_equal(position, self.env.agents[handle].target): last_is_target = True break exploring = False # Check number of possible transitions for agent and total number of transitions in cell (type) possible_transitions = self.env.rail.get_transitions(*position, direction) num_transitions = np.count_nonzero(possible_transitions) # cell_transitions = self.env.rail.get_transitions(*position, direction) transition_bit = bin(self.env.rail.get_full_transitions(*position)) total_transitions = transition_bit.count("1") if num_transitions == 1: # Check if dead-end, or if we can go forward along direction nbits = total_transitions if nbits == 1: # Dead-end! last_is_dead_end = True if self.check_agent_descision is not None: ret_agents_on_switch, ret_agents_near_to_switch, agents_near_to_switch_all = \ self.check_agent_descision(position, direction, self.switches_list, self.switches_neighbours_list) if ret_agents_on_switch: last_is_a_decision_cell = True break exploring = True # convert one-hot encoding to 0,1,2,3 cell_transitions = self.env.rail.get_transitions(*position, direction) direction = np.argmax(cell_transitions) position = get_new_position(position, direction) cnt += 1 if cnt > 1000: exploring = False # ############################# # ############################# # Modify here to append new / different features for each visited cell! node = MyTreeObsForRailEnv.Node(dist_min_to_target=dist_min_to_target, target_encountered=target_encountered, num_agents_opposite_direction=other_agent_opposite_direction, num_agents_same_direction=other_agent_same_direction, childs={}) # ############################# # ############################# # Start from the current orientation, and see which transitions are available; # organize them as [left, forward, right, back], relative to the current orientation # Get the possible transitions possible_transitions = self.env.rail.get_transitions(*position, direction) for i, branch_direction in enumerate([(direction + 4 + i) % 4 for i in range(-1, 3)]): if last_is_dead_end and self.env.rail.get_transition((*position, direction), (branch_direction + 2) % 4): # Swap forward and back in case of dead-end, so that an agent can learn that going forward takes # it back new_cell = get_new_position(position, (branch_direction + 2) % 4) branch_observation, branch_visited = self._explore_branch(handle, new_cell, (branch_direction + 2) % 4, tot_dist + 1, depth + 1) node.childs[self.tree_explored_actions_char[i]] = branch_observation if len(branch_visited) != 0: visited |= branch_visited elif last_is_a_decision_cell and possible_transitions[branch_direction]: new_cell = get_new_position(position, branch_direction) branch_observation, branch_visited = self._explore_branch(handle, new_cell, branch_direction, tot_dist + 1, depth + 1) node.childs[self.tree_explored_actions_char[i]] = branch_observation if len(branch_visited) != 0: visited |= branch_visited else: # no exploring possible, add just cells with infinity node.childs[self.tree_explored_actions_char[i]] = -np.inf if depth == self.max_depth: node.childs.clear() return node, visited def util_print_obs_subtree(self, tree: Node): """ Utility function to print tree observations returned by this object. """ self.print_node_features(tree, "root", "") for direction in self.tree_explored_actions_char: self.print_subtree(tree.childs[direction], direction, "\t") @staticmethod def print_node_features(node: Node, label, indent): print(indent, "Direction ", label, ": ", node.num_agents_same_direction, ", ", node.num_agents_opposite_direction) def print_subtree(self, node, label, indent): if node == -np.inf or not node: print(indent, "Direction ", label, ": -np.inf") return self.print_node_features(node, label, indent) if not node.childs: return for direction in self.tree_explored_actions_char: self.print_subtree(node.childs[direction], direction, indent + "\t") def set_env(self, env: Environment): super().set_env(env) if self.predictor: self.predictor.set_env(self.env) def _reverse_dir(self, direction): return int((direction + 2) % 4) class GlobalObsForRailEnv(ObservationBuilder): """ Gives a global observation of the entire rail environment. The observation is composed of the following elements: - transition map array with dimensions (env.height, env.width, 16),\ assuming 16 bits encoding of transitions. - obs_agents_state: A 3D array (map_height, map_width, 5) with - first channel containing the agents position and direction - second channel containing the other agents positions and direction - third channel containing agent/other agent malfunctions - fourth channel containing agent/other agent fractional speeds - fifth channel containing number of other agents ready to depart - obs_targets: Two 2D arrays (map_height, map_width, 2) containing respectively the position of the given agent\ target and the positions of the other agents targets (flag only, no counter!). """ def __init__(self): super(GlobalObsForRailEnv, self).__init__() def set_env(self, env: Environment): super().set_env(env) def reset(self): self.rail_obs = np.zeros((self.env.height, self.env.width, 16)) for i in range(self.rail_obs.shape[0]): for j in range(self.rail_obs.shape[1]): bitlist = [int(digit) for digit in bin(self.env.rail.get_full_transitions(i, j))[2:]] bitlist = [0] * (16 - len(bitlist)) + bitlist self.rail_obs[i, j] = np.array(bitlist) def get(self, handle: int = 0) -> (np.ndarray, np.ndarray, np.ndarray): agent = self.env.agents[handle] if agent.status == RailAgentStatus.READY_TO_DEPART: agent_virtual_position = agent.initial_position elif agent.status == RailAgentStatus.ACTIVE: agent_virtual_position = agent.position elif agent.status == RailAgentStatus.DONE: agent_virtual_position = agent.target else: return None obs_targets = np.zeros((self.env.height, self.env.width, 2)) obs_agents_state = np.zeros((self.env.height, self.env.width, 5)) - 1 # TODO can we do this more elegantly? # for r in range(self.env.height): # for c in range(self.env.width): # obs_agents_state[(r, c)][4] = 0 obs_agents_state[:, :, 4] = 0 obs_agents_state[agent_virtual_position][0] = agent.direction obs_targets[agent.target][0] = 1 for i in range(len(self.env.agents)): other_agent: EnvAgent = self.env.agents[i] # ignore other agents not in the grid any more if other_agent.status == RailAgentStatus.DONE_REMOVED: continue obs_targets[other_agent.target][1] = 1 # second to fourth channel only if in the grid if other_agent.position is not None: # second channel only for other agents if i != handle: obs_agents_state[other_agent.position][1] = other_agent.direction obs_agents_state[other_agent.position][2] = other_agent.malfunction_data['malfunction'] obs_agents_state[other_agent.position][3] = other_agent.speed_data['speed'] # fifth channel: all ready to depart on this position if other_agent.status == RailAgentStatus.READY_TO_DEPART: obs_agents_state[other_agent.initial_position][4] += 1 return self.rail_obs, obs_agents_state, obs_targets class LocalObsForRailEnv(ObservationBuilder): """ !!!!!!WARNING!!! THIS IS DEPRACTED AND NOT UPDATED TO FLATLAND 2.0!!!!! Gives a local observation of the rail environment around the agent. The observation is composed of the following elements: - transition map array of the local environment around the given agent, \ with dimensions (view_height,2*view_width+1, 16), \ assuming 16 bits encoding of transitions. - Two 2D arrays (view_height,2*view_width+1, 2) containing respectively, \ if they are in the agent's vision range, its target position, the positions of the other targets. - A 2D array (view_height,2*view_width+1, 4) containing the one hot encoding of directions \ of the other agents at their position coordinates, if they are in the agent's vision range. - A 4 elements array with one hot encoding of the direction. Use the parameters view_width and view_height to define the rectangular view of the agent. The center parameters moves the agent along the height axis of this rectangle. If it is 0 the agent only has observation in front of it. .. deprecated:: 2.0.0 """ def __init__(self, view_width, view_height, center): super(LocalObsForRailEnv, self).__init__() self.view_width = view_width self.view_height = view_height self.center = center self.max_padding = max(self.view_width, self.view_height - self.center) def reset(self): # We build the transition map with a view_radius empty cells expansion on each side. # This helps to collect the local transition map view when the agent is close to a border. self.max_padding = max(self.view_width, self.view_height) self.rail_obs = np.zeros((self.env.height, self.env.width, 16)) for i in range(self.env.height): for j in range(self.env.width): bitlist = [int(digit) for digit in bin(self.env.rail.get_full_transitions(i, j))[2:]] bitlist = [0] * (16 - len(bitlist)) + bitlist self.rail_obs[i, j] = np.array(bitlist) def get(self, handle: int = 0) -> (np.ndarray, np.ndarray, np.ndarray, np.ndarray): agents = self.env.agents agent = agents[handle] # Correct agents position for padding # agent_rel_pos[0] = agent.position[0] + self.max_padding # agent_rel_pos[1] = agent.position[1] + self.max_padding # Collect visible cells as set to be plotted visited, rel_coords = self.field_of_view(agent.position, agent.direction, ) local_rail_obs = None # Add the visible cells to the observed cells self.env.dev_obs_dict[handle] = set(visited) # Locate observed agents and their coresponding targets local_rail_obs = np.zeros((self.view_height, 2 * self.view_width + 1, 16)) obs_map_state = np.zeros((self.view_height, 2 * self.view_width + 1, 2)) obs_other_agents_state = np.zeros((self.view_height, 2 * self.view_width + 1, 4)) _idx = 0 for pos in visited: curr_rel_coord = rel_coords[_idx] local_rail_obs[curr_rel_coord[0], curr_rel_coord[1], :] = self.rail_obs[pos[0], pos[1], :] if pos == agent.target: obs_map_state[curr_rel_coord[0], curr_rel_coord[1], 0] = 1 else: for tmp_agent in agents: if pos == tmp_agent.target: obs_map_state[curr_rel_coord[0], curr_rel_coord[1], 1] = 1 if pos != agent.position: for tmp_agent in agents: if pos == tmp_agent.position: obs_other_agents_state[curr_rel_coord[0], curr_rel_coord[1], :] = np.identity(4)[ tmp_agent.direction] _idx += 1 direction = np.identity(4)[agent.direction] return local_rail_obs, obs_map_state, obs_other_agents_state, direction def get_many(self, handles: Optional[List[int]] = None) -> Dict[ int, Tuple[np.ndarray, np.ndarray, np.ndarray, np.ndarray]]: """ Called whenever an observation has to be computed for the `env` environment, for each agent with handle in the `handles` list. """ return super().get_many(handles) def field_of_view(self, position, direction, state=None): # Compute the local field of view for an agent in the environment data_collection = False if state is not None: temp_visible_data = np.zeros(shape=(self.view_height, 2 * self.view_width + 1, 16)) data_collection = True if direction == 0: origin = (position[0] + self.center, position[1] - self.view_width) elif direction == 1: origin = (position[0] - self.view_width, position[1] - self.center) elif direction == 2: origin = (position[0] - self.center, position[1] + self.view_width) else: origin = (position[0] + self.view_width, position[1] + self.center) visible = list() rel_coords = list() for h in range(self.view_height): for w in range(2 * self.view_width + 1): if direction == 0: if 0 <= origin[0] - h < self.env.height and 0 <= origin[1] + w < self.env.width: visible.append((origin[0] - h, origin[1] + w)) rel_coords.append((h, w)) # if data_collection: # temp_visible_data[h, w, :] = state[origin[0] - h, origin[1] + w, :] elif direction == 1: if 0 <= origin[0] + w < self.env.height and 0 <= origin[1] + h < self.env.width: visible.append((origin[0] + w, origin[1] + h)) rel_coords.append((h, w)) # if data_collection: # temp_visible_data[h, w, :] = state[origin[0] + w, origin[1] + h, :] elif direction == 2: if 0 <= origin[0] + h < self.env.height and 0 <= origin[1] - w < self.env.width: visible.append((origin[0] + h, origin[1] - w)) rel_coords.append((h, w)) # if data_collection: # temp_visible_data[h, w, :] = state[origin[0] + h, origin[1] - w, :] else: if 0 <= origin[0] - w < self.env.height and 0 <= origin[1] - h < self.env.width: visible.append((origin[0] - w, origin[1] - h)) rel_coords.append((h, w)) # if data_collection: # temp_visible_data[h, w, :] = state[origin[0] - w, origin[1] - h, :] if data_collection: return temp_visible_data else: return visible, rel_coords def _split_node_into_feature_groups(node: MyTreeObsForRailEnv.Node, dist_min_to_target: int) -> (np.ndarray, np.ndarray, np.ndarray): data = np.zeros(2) data[0] = 2.0 * int(node.num_agents_opposite_direction > 0) - 1.0 # data[1] = 2.0 * int(node.num_agents_same_direction > 0) - 1.0 data[1] = 2.0 * int(node.target_encountered > 0) - 1.0 return data def _split_subtree_into_feature_groups(node: MyTreeObsForRailEnv.Node, dist_min_to_target: int, current_tree_depth: int, max_tree_depth: int) -> ( np.ndarray, np.ndarray, np.ndarray): if node == -np.inf: remaining_depth = max_tree_depth - current_tree_depth # reference: https://stackoverflow.com/questions/515214/total-number-of-nodes-in-a-tree-data-structure num_remaining_nodes = int((4 ** (remaining_depth + 1) - 1) / (4 - 1)) return [0] * num_remaining_nodes * 2 data = _split_node_into_feature_groups(node, dist_min_to_target) if not node.childs: return data for direction in MyTreeObsForRailEnv.tree_explored_actions_char: sub_data = _split_subtree_into_feature_groups(node.childs[direction], node.dist_min_to_target, current_tree_depth + 1, max_tree_depth) data = np.concatenate((data, sub_data)) return data def split_tree_into_feature_groups(tree: MyTreeObsForRailEnv.Node, max_tree_depth: int) -> ( np.ndarray, np.ndarray, np.ndarray): """ This function splits the tree into three difference arrays of values """ data = _split_node_into_feature_groups(tree, 1000000.0) for direction in MyTreeObsForRailEnv.tree_explored_actions_char: sub_data = _split_subtree_into_feature_groups(tree.childs[direction], 1000000.0, 1, max_tree_depth) data = np.concatenate((data, sub_data)) return data def normalize_observation(observation: MyTreeObsForRailEnv.Node, tree_depth: int): """ This function normalizes the observation used by the RL algorithm """ data = split_tree_into_feature_groups(observation, tree_depth) normalized_obs = data # navigate_info navigate_info = np.zeros(4) action_info = np.zeros(4) np.seterr(all='raise') try: dm = observation.dist_min_to_target if observation.childs['L'] != -np.inf: navigate_info[0] = dm - observation.childs['L'].dist_min_to_target action_info[0] = 1 if observation.childs['F'] != -np.inf: navigate_info[1] = dm - observation.childs['F'].dist_min_to_target action_info[1] = 1 if observation.childs['R'] != -np.inf: navigate_info[2] = dm - observation.childs['R'].dist_min_to_target action_info[2] = 1 if observation.childs['B'] != -np.inf: navigate_info[3] = dm - observation.childs['B'].dist_min_to_target action_info[3] = 1 except: navigate_info = np.ones(4) normalized_obs = np.zeros(len(normalized_obs)) # navigate_info_2 = np.copy(navigate_info) # max_v = np.max(navigate_info_2) # navigate_info_2 = navigate_info_2 / max_v # navigate_info_2[navigate_info_2 < 1] = -1 max_v = np.max(navigate_info) navigate_info = navigate_info / max_v navigate_info[navigate_info < 0] = -1 # navigate_info[abs(navigate_info) < 1] = 0 # normalized_obs = navigate_info # navigate_info = np.concatenate((navigate_info, action_info)) normalized_obs = np.concatenate((navigate_info, normalized_obs)) # normalized_obs = np.concatenate((navigate_info, navigate_info_2)) # print(normalized_obs) return normalized_obs