From 4257fc8a775ed3571e51601cb5e5da322883bf94 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Laura=20Kl=C3=BCnder?= <laura@codingcatgirl.de>
Date: Thu, 22 Dec 2016 19:43:01 +0100
Subject: [PATCH] circumvent weird bug in shapely

---
 src/c3nav/mapdata/models/level.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/c3nav/mapdata/models/level.py b/src/c3nav/mapdata/models/level.py
index 2df1cc40..5646c257 100644
--- a/src/c3nav/mapdata/models/level.py
+++ b/src/c3nav/mapdata/models/level.py
@@ -178,7 +178,7 @@ class LevelGeometries():
 
     @cached_property
     def accessible(self):
-        return self.areas.difference(self.holes).difference(self.obstacles)
+        return self.areas.difference(cascaded_union([self.holes, self.obstacles]))
 
     @cached_property
     def accessible_without_oneways(self):