create GraphArea.check_connection

src/c3nav/routing/area.py

@@ -30,15 +30,24 @@ class GraphArea():
 
     def build_connections(self):
         for point1, point2 in combinations(self._built_points, 2):
+
+            there, back = self.check_connection(point1, point2)
+
+            if there is not None:
+                point1.connect_to(point2, ctype=there)
+
+            if back is not None:
+                point2.connect_to(point1, ctype=back)
+
+    def check_connection(self, point1, point2):
         path = Path(np.vstack((point1.xy, point2.xy)))
 
         # lies within room
         if self.mpl_clear.intersects_path(path):
-                continue
+            return None, None
 
         # stair checker
         angle = coord_angle(point1.xy, point2.xy)
-            valid = True
         stair_direction_up = None
         for stair_path, stair_angle in self.mpl_stairs:
             if not path.intersects_path(stair_path):
@@ -50,19 +59,13 @@ class GraphArea():
             if stair_direction_up is None:
                 stair_direction_up = new_direction_up
             elif stair_direction_up != new_direction_up:
-                    valid = False
-                    break
+                return None, None
 
             if not (40 < abs(angle_diff) < 150):
-                    valid = False
-                    break
-
-            if not valid:
-                continue
+                return None, None
 
         # escalator checker
         angle = coord_angle(point1.xy, point2.xy)
-            valid = True
         escalator_direction_up = None
         escalator_swap_direction = False
         for escalator in self.escalators:
@@ -71,28 +74,25 @@ class GraphArea():
 
             if escalator_direction_up is not None:
                 # only one escalator per connection
-                    valid = False
-                    break
+                return None, None
 
             angle_diff = ((escalator.angle - angle + 180) % 360) - 180
 
             escalator_direction_up = (angle_diff > 0)
             escalator_swap_direction = (escalator_direction_up != escalator.direction_up)
 
-            if not valid:
-                continue
-
         if stair_direction_up is not None:
-                point1.connect_to(point2, ctype=('stairs_up' if stair_direction_up else 'stairs_down'))
-                point2.connect_to(point1, ctype=('stairs_down' if stair_direction_up else 'stairs_up'))
+            return (
+                ('stairs_up' if stair_direction_up else 'stairs_down'),
+                ('stairs_down' if stair_direction_up else 'stairs_up'),
+            )
         elif escalator_direction_up is not None:
             if not escalator_swap_direction:
-                    point1.connect_to(point2, ctype=('escalator_up' if escalator_direction_up else 'escalator_down'))
+                return ('escalator_up' if escalator_direction_up else 'escalator_down'), None
             else:
-                    point2.connect_to(point1, ctype=('escalator_down' if escalator_direction_up else 'escalator_up'))
-            else:
-                point1.connect_to(point2)
-                point2.connect_to(point1)
+                return None, ('escalator_down' if escalator_direction_up else 'escalator_up')
+
+        return '', ''
 
     def add_point(self, point):
         if not self.mpl_clear.contains_point(point.xy):