don't store update list as tuple, we can't modify it then
@@ -53,8 +53,9 @@ class MapHistory(LevelGeometryIndexed):
def simplify(self):
# remove updates that have no longer any array cells
new_updates = ((i, update, (self.data == i)) for i, update in enumerate(self.updates))
- self.updates, new_affected = zip(*((update, affected) for i, update, affected in new_updates
+ new_updates, new_affected = zip(*((update, affected) for i, update, affected in new_updates
if i == 0 or affected.any()))
+ self.updates = list(new_updates)
for i, affected in enumerate(new_affected):
self.data[affected] = i
