connection updated for disjunct nodes

examples/flatland_2_0_example.py

@@ -34,7 +34,7 @@ env = RailEnv(width=50,
               height=50,
               rail_generator=sparse_rail_generator(num_cities=9,  # Number of cities in map (where train stations are)
                                                    num_intersections=0,  # Number of intersections (no start / target)
-                                                   num_trainstations=10,  # Number of possible start/targets on map
+                                                   num_trainstations=15,  # Number of possible start/targets on map
                                                    min_node_dist=3,  # Minimal distance of nodes
                                                    node_radius=4,  # Proximity of stations to city center
                                                    num_neighb=4,  # Number of connections to other cities/intersections

flatland/envs/rail_generators.py

@@ -743,12 +743,22 @@ def sparse_rail_generator(num_cities=5, num_intersections=4, num_trainstations=2
         if len(boarder_connections) > 0:
             to_be_deleted = []
             for disjunct_node in boarder_connections:
-                print(disjunct_node)
-                conn = connect_nodes(rail_trans, grid_map,
-                                     disjunct_node[0],
-                                     train_stations[disjunct_node[1]][0])
+                if len(train_stations[disjunct_node[1]]) > 0:
+                    conn = connect_nodes(rail_trans, grid_map,
+                                         disjunct_node[0],
+                                         train_stations[disjunct_node[1]][-1])
+                else:
+                    conn = connect_nodes(rail_trans, grid_map,
+                                         disjunct_node[0],
+                                         node_positions[disjunct_node[1]])
                 if len(conn) > 0:
                     to_be_deleted.append(disjunct_node)
+                else:
+                    conn = connect_nodes(rail_trans, grid_map,
+                                         disjunct_node[0],
+                                         node_positions[disjunct_node[1]])
+                    if len(conn) > 0:
+                        to_be_deleted.append(disjunct_node)
 
         for tbd in to_be_deleted:
             boarder_connections.remove(tbd)
@@ -758,8 +768,6 @@ def sparse_rail_generator(num_cities=5, num_intersections=4, num_trainstations=2
         for cell_to_fix in flat_trainstation_list:
             grid_map.fix_transitions(cell_to_fix)
 
-        grid_map.fix_transitions((station_x, station_y))
-
         flat_list = [item for sublist in connection_points for item in sublist]
 
         for cell_to_fix in flat_list: