ignore empty altitude areas

src/c3nav/mapdata/utils/geometry.py

@@ -72,11 +72,7 @@ def good_representative_point(geometry):
     if isinstance(geometry, Point):
         return geometry
     c = geometry.centroid
-    try:
-        x1, y1, x2, y2 = geometry.bounds
-    except ValueError:
-        # jup, this can happen
-        return c
+    x1, y1, x2, y2 = geometry.bounds
     lines = (tuple(assert_multilinestring(LineString(((x1, c.y), (x2, c.y))).intersection(geometry))) +
              tuple(assert_multilinestring(LineString(((c.x, y1), (c.x, y2))).intersection(geometry))))
     return min(lines, key=lambda line: (line.distance(c), line.length),

src/c3nav/routing/router.py

@@ -119,7 +119,11 @@ class Router:
                     if not space.geometry_prep.intersects(area.geometry):
                         continue
                     for subgeom in assert_multipolygon(accessible_geom.intersection(area.geometry)):
+                        if subgeom.is_empty:
+                            continue
                         area_clear_geom = unary_union(tuple(get_rings(subgeom.difference(obstacles_geom))))
+                        if area_clear_geom.is_empty:
+                            continue
                         area = RouterAltitudeArea(subgeom, area_clear_geom,
                                                   area.altitude, area.altitude2, area.point1, area.point2)
                         area_nodes = tuple(node for node in space_nodes if area.geometry_prep.intersects(node.point))