Get a sneak peek at whats next for Permanent Hazards on our April 7th Office Hours!

Post Reply
Forum rules
The place to ask for help when editing in the UK.

Map Editing Guidelines . Join the UK Discord Server

CF11 8JQ - wrong routing from this postcode

Post by A123drive
When selecting this postcode (CF11 8JQ) as the starting point, the suggested route snaps to the elevated dual carriageway (A4232) instead of the nearest ground level segment ("West Point Industrial Estate").

In both the app and on the live map the origin flag is correctly placed slighty north of both roads, so the expected (and correct) behaviour would be to suggest a route starting from the (ground level) road "West Point Industrial Estate".

This is the link in the map editor:
https://www.waze.com/editor/?env=row&lo ... ueFilter=1

On the contrary the postcode works fine when used as the destination.
A123drive
Posts: 2

POSTER_ID:17190878

1

Send a message

Post by A123drive
Thanks for your replies. That does make a lot of sense, and I fear that it will be difficult to find a solution in this particular case, because the A4232 passes literally directly above the access road, and worse runs in parallel with it for that section.

The result is that it continues thinking you're on top until well past the roundabout (Penarth Road) at the bottom - at which point one may well have turned the "wrong" way at that same roundabout.

So is this something that can only be solved by having more accurate GPS (Galileo), thus allowing the tolerance to be reduced at the server side?

Or is there a possibility of reducing this tolerance based on other factors, for example speed, navigation history, etc?
For example, unless traffic is moving very, very slowly, one might expect to be moving along the A4232 at 30+ mph prior to the routing request, a speed which isn't really possible on the access road (in this case).
Of course, if Waze wasn't running, then that isn't of any help. However, if located in an adjacent building on Wifi and starting a route request there, it is much less likely that I would be sitting in a car driving along a fast road. Maybe the connection type is a small indicator (Wifi vs mobile internet), plus presence (or absense) of a GPS signal, even if accurate location is turned on. (On the App this condition seems to trigger the message "No GPS signal - try going outdoors")

Also, if completely stationary then the likelihood of being on top of the dual carriageway should decrease (exponentially?) with distance of the coordinates. In particular, one would expect a pretty accurate signal when elevated by 20m+ off the ground.

Of course that all sounds logical, but may not work in the algorithm or in practice. But it would make the app much more awesome, considering that Google Maps, Tomtom and Copilot are able to cope with this. (when the starting point is set to the access road, otherwise it is definitely tricky for any navigation app to distinguish ground from elevation based on coordinates alone)

So actually, one thing that certainly might help would be to consider all postcode based routing requests to refer to ground level. It is highly unusual to have a postcode referring to an elevated road. Then, if Waze could remember me setting the starting point to that postcode, and I haven't moved further away than a certain distance, it would try to snap me at ground level between that postcode and current location.

I don't know - have been using the workaround of starting slightly down the road for a while, or clicking "set as starting point" before every new routes request - but perhaps the above can give someone some ideas...
A123drive
Posts: 2
Send a message

Post by PealRinger
Hi there - glad you found the forums after chatting earlier and well done on your first post.

I've seen this before where Waze will snap the same starting point to a different segment based on only choosing a different destination. Hopefully someone here may know why that is?

Unfortunately the only other solution is to pick a starting point slightly further away from the A4232 and then ignore the app for a minute until it snaps to your correct location.
PealRinger
PartnerCoordinator
PartnerCoordinator
Posts: 1984
Has thanked: 226 times
Been thanked: 696 times
Send a message

Post by Twister-UK
It looks a bit like the routing calcs are influenced by how easy it is to get to the destination point from the assumed start point - in this case, any route I've asked for (results only valid within the Livemap environment, in-app results may differ, see packs for details...) where the route can easily start on the estate access road does start there, whereas any route that would be easier to start on the adjacent A4232 (heading in either direction, so it's not even simply snapping to the nearest segment of that road) starts there instead.

This in turn may be related to how the routing server handles the issue of GPS accuracy - our phones (and Livemap) may well be asking the server for a route from a specific set of co-ords, but generally when we ask for a route from the app it's based on our current location rather than a saved location, so the server may be assuming that all starting points will have a bit of "wiggle room" in their actual positions, and looking for the most optimal starting point within that distance from the co-ords provided.
Twister-UK
Waze Local Champs
Waze Local Champs
Posts: 4671
Answers: 2
Has thanked: 736 times
Been thanked: 4686 times
Send a message
Chris (not to be confused with Chris or Chris, or even Tim, Stu, or any of the other champs team...)
AM SE England & Shetland Islands, UK Local Champ, WME Beta Tester & ScriptMangler
WME/Livemap enhancement scripts @ GreasyFork


https://chizzum.com/greasemonkey/images/beta.pnghttps://chizzum.com/greasemonkey/images/s0400.pnghttps://chizzum.com/greasemonkey/images/c5s.png