def test_valid_railenv_transitions(): rail_env_trans = RailEnvTransitions() # directions: # 'N': 0 # 'E': 1 # 'S': 2 # 'W': 3 for i in range(2): assert (rail_env_trans.get_transitions(int('1100110000110011', 2), i) == (1, 1, 0, 0)) assert (rail_env_trans.get_transitions(int('1100110000110011', 2), 2 + i) == (0, 0, 1, 1)) no_transition_cell = int('0000000000000000', 2) for i in range(4): assert (rail_env_trans.get_transitions(no_transition_cell, i) == (0, 0, 0, 0)) # Facing south, going south north_south_transition = rail_env_trans.set_transitions( no_transition_cell, 2, (0, 0, 1, 0)) assert (rail_env_trans.set_transition(north_south_transition, 2, 2, 0) == no_transition_cell) assert (rail_env_trans.get_transition(north_south_transition, 2, 2)) # Facing north, going east south_east_transition = \ rail_env_trans.set_transition(no_transition_cell, 0, 1, 1) assert (rail_env_trans.get_transition(south_east_transition, 0, 1)) # The opposite transitions are not feasible assert (not rail_env_trans.get_transition(north_south_transition, 2, 0)) assert (not rail_env_trans.get_transition(south_east_transition, 2, 1)) east_west_transition = rail_env_trans.rotate_transition( north_south_transition, 90) north_west_transition = rail_env_trans.rotate_transition( south_east_transition, 180) # Facing west, going west assert (rail_env_trans.get_transition(east_west_transition, 3, 3)) # Facing south, going west assert (rail_env_trans.get_transition(north_west_transition, 2, 3)) assert (south_east_transition == rail_env_trans.rotate_transition( south_east_transition, 360))
def generator(width: int, height: int, num_agents: int, num_resets: int = 0, np_random: RandomState = None) -> RailGenerator: t_utils = RailEnvTransitions() transition_probability = cell_type_relative_proportion transitions_templates_ = [] transition_probabilities = [] for i in range(len(t_utils.transitions)): # don't include dead-ends if t_utils.transitions[i] == int('0010000000000000', 2): continue all_transitions = 0 for dir_ in range(4): trans = t_utils.get_transitions(t_utils.transitions[i], dir_) all_transitions |= (trans[0] << 3) | \ (trans[1] << 2) | \ (trans[2] << 1) | \ (trans[3]) template = [int(x) for x in bin(all_transitions)[2:]] template = [0] * (4 - len(template)) + template # add all rotations for rot in [0, 90, 180, 270]: transitions_templates_.append( (template, t_utils.rotate_transition(t_utils.transitions[i], rot))) transition_probabilities.append(transition_probability[i]) template = [template[-1]] + template[:-1] def get_matching_templates(template): """ Returns a list of possible transition maps for a given template Parameters: ------ template:List[int] Returns: ------ List[int] """ ret = [] for i in range(len(transitions_templates_)): is_match = True for j in range(4): if template[j] >= 0 and template[ j] != transitions_templates_[i][0][j]: is_match = False break if is_match: ret.append((transitions_templates_[i][1], transition_probabilities[i])) return ret MAX_INSERTIONS = (width - 2) * (height - 2) * 10 MAX_ATTEMPTS_FROM_SCRATCH = 10 attempt_number = 0 while attempt_number < MAX_ATTEMPTS_FROM_SCRATCH: cells_to_fill = [] rail = [] for r in range(height): rail.append([None] * width) if r > 0 and r < height - 1: cells_to_fill = cells_to_fill + [ (r, c) for c in range(1, width - 1) ] num_insertions = 0 while num_insertions < MAX_INSERTIONS and len(cells_to_fill) > 0: cell = cells_to_fill[np_random.choice(len(cells_to_fill), 1)[0]] cells_to_fill.remove(cell) row = cell[0] col = cell[1] # look at its neighbors and see what are the possible transitions # that can be chosen from, if any. valid_template = [-1, -1, -1, -1] for el in [(0, 2, (-1, 0)), (1, 3, (0, 1)), (2, 0, (1, 0)), (3, 1, (0, -1))]: # N, E, S, W neigh_trans = rail[row + el[2][0]][col + el[2][1]] if neigh_trans is not None: # select transition coming from facing direction el[1] and # moving to direction el[1] max_bit = 0 for k in range(4): max_bit |= t_utils.get_transition( neigh_trans, k, el[1]) if max_bit: valid_template[el[0]] = 1 else: valid_template[el[0]] = 0 possible_cell_transitions = get_matching_templates( valid_template) if len(possible_cell_transitions) == 0: # NO VALID TRANSITIONS # no cell can be filled in without violating some transitions # can a dead-end solve the problem? if valid_template.count(1) == 1: for k in range(4): if valid_template[k] == 1: rot = 0 if k == 0: rot = 180 elif k == 1: rot = 270 elif k == 2: rot = 0 elif k == 3: rot = 90 rail[row][col] = t_utils.rotate_transition( int('0010000000000000', 2), rot) num_insertions += 1 break else: # can I get valid transitions by removing a single # neighboring cell? bestk = -1 besttrans = [] for k in range(4): tmp_template = valid_template[:] tmp_template[k] = -1 possible_cell_transitions = get_matching_templates( tmp_template) if len(possible_cell_transitions) > len(besttrans): besttrans = possible_cell_transitions bestk = k if bestk >= 0: # Replace the corresponding cell with None, append it # to cells to fill, fill in a transition in the current # cell. replace_row = row - 1 replace_col = col if bestk == 1: replace_row = row replace_col = col + 1 elif bestk == 2: replace_row = row + 1 replace_col = col elif bestk == 3: replace_row = row replace_col = col - 1 cells_to_fill.append((replace_row, replace_col)) rail[replace_row][replace_col] = None possible_transitions, possible_probabilities = zip( *besttrans) possible_probabilities = [ p / sum(possible_probabilities) for p in possible_probabilities ] rail[row][col] = np_random.choice( possible_transitions, p=possible_probabilities) num_insertions += 1 else: print('WARNING: still nothing!') rail[row][col] = int('0000000000000000', 2) num_insertions += 1 pass else: possible_transitions, possible_probabilities = zip( *possible_cell_transitions) possible_probabilities = [ p / sum(possible_probabilities) for p in possible_probabilities ] rail[row][col] = np_random.choice(possible_transitions, p=possible_probabilities) num_insertions += 1 if num_insertions == MAX_INSERTIONS: # Failed to generate a valid level; try again for a number of times attempt_number += 1 else: break if attempt_number == MAX_ATTEMPTS_FROM_SCRATCH: print('ERROR: failed to generate level') # Finally pad the border of the map with dead-ends to avoid border issues; # at most 1 transition in the neigh cell for r in range(height): # Check for transitions coming from [r][1] to WEST max_bit = 0 neigh_trans = rail[r][1] if neigh_trans is not None: for k in range(4): neigh_trans_from_direction = (neigh_trans >> ((3 - k) * 4)) & (2**4 - 1) max_bit = max_bit | (neigh_trans_from_direction & 1) if max_bit: rail[r][0] = t_utils.rotate_transition( int('0010000000000000', 2), 270) else: rail[r][0] = int('0000000000000000', 2) # Check for transitions coming from [r][-2] to EAST max_bit = 0 neigh_trans = rail[r][-2] if neigh_trans is not None: for k in range(4): neigh_trans_from_direction = (neigh_trans >> ((3 - k) * 4)) & (2**4 - 1) max_bit = max_bit | (neigh_trans_from_direction & (1 << 2)) if max_bit: rail[r][-1] = t_utils.rotate_transition( int('0010000000000000', 2), 90) else: rail[r][-1] = int('0000000000000000', 2) for c in range(width): # Check for transitions coming from [1][c] to NORTH max_bit = 0 neigh_trans = rail[1][c] if neigh_trans is not None: for k in range(4): neigh_trans_from_direction = (neigh_trans >> ((3 - k) * 4)) & (2**4 - 1) max_bit = max_bit | (neigh_trans_from_direction & (1 << 3)) if max_bit: rail[0][c] = int('0010000000000000', 2) else: rail[0][c] = int('0000000000000000', 2) # Check for transitions coming from [-2][c] to SOUTH max_bit = 0 neigh_trans = rail[-2][c] if neigh_trans is not None: for k in range(4): neigh_trans_from_direction = (neigh_trans >> ((3 - k) * 4)) & (2**4 - 1) max_bit = max_bit | (neigh_trans_from_direction & (1 << 1)) if max_bit: rail[-1][c] = t_utils.rotate_transition( int('0010000000000000', 2), 180) else: rail[-1][c] = int('0000000000000000', 2) # For display only, wrong levels for r in range(height): for c in range(width): if rail[r][c] is None: rail[r][c] = int('0000000000000000', 2) tmp_rail = np.asarray(rail, dtype=np.uint16) return_rail = GridTransitionMap(width=width, height=height, transitions=t_utils) return_rail.grid = tmp_rail return return_rail, None