Not sure where this needs to go in the wiki, but here is some info I received from Ohad regarding city polygons:
The city polygons are being re-calculated every day, if the length of the segments in the city is changed by more than 5%. This should work for most cases, but is not ideal.
We are working on a process that will recalculate all the city polygons every 10 days - 10% of the cities in each day.
I asked to clarify what was "re-calculated every day" and he stated everything to do with cities: city layer shading, names, removing shading/visible names from WME and client map with no associated segments.
I did not ask to clarify what "length of the segments in the city" refers to exactly. It could be the length of the perimeter (sounds reasonable), but could also mean if 5% of the segments within the city have their length changed (that's an odd one).
But either way, if a city is shrunk down to no segments, that's a 100% change any way you slice it, so that city should disappear with the very next map update according to the information given.
Hah, okay, I'll explain what I meant above, here.
I still run into cases where I'm certain I've eliminated all segments of a city, such that the name (and its 'stickiness to that location') should disappear.
But then, I get this situation: https://www.waze.com/editor/?zoom=3&lat ... TFTFTTTTFT
All segments and even landmarks were changed to 'Live Oak CDP' so that I could move the name 'Live Oak' to the city several hundred miles to the north, but here the label and location remains, weeks later.
I have a feeling that the check being done by the city scripts is acting like this (admittedly a guess on my part):
- Code: Select all
Old Length New length Recalculate?
1000 1000 No (Ratio is 1, +0%)
1000 1025 No (Ratio is 1.025, +2.5%)
1000 900 Yes (Ratio is 0.90, -10.0%)
1000 2 Yes (Ratio is 0.002, -99.8%)
1000 0 No (Doesn't "delete city" for whatever reason)
0 0 No (Same as above; won't recalc/delete city)
It's those last two that I think are the issue. Once a city's 'length' is zero, the script doesn't seem to identify (and properly) remove that city from the map so it can be relocated, or just "deleted".
This would explain why we can 'walk' a city's location to a new place with segments, but why we can't just "remove" it and put it somewhere else after a city recalc, without intervention from Waze.