[Talk-ca] Telenav mapping turn restrictions

Andrew Lester a-lester at shaw.ca
Tue Apr 25 04:43:40 UTC 2017

Okay Telenav, you win. 

I've come across many mapping issues over the last few weeks, and nearly all of them have been created by Telenav mappers. These include malformed restrictions that prevent legal routing (these are in addition to the subjective turn restrictions discussed previously), adding names to driveways in strata developments (that I had previously removed), replacing my on-the-ground mapping with their own based solely on out-of-date imagery or the often-questionable Geobase, wildly incorrect highway classifications, and much more. Since these mappers seem to be intent on destroying the map (their actions can't be classified as anything but destructive), I'm throwing in the towel. If Telenav wishes to pay their employees to degrade the quality of the map, there isn't much I can do as a lone hobbyist in my spare time. At the rate I'm seeing things going, it won't be long until the OSM database has been degraded to the state that Google Maps is in these days since they started letting any yahoo edit their map. 

Going forward, I'm going to stick to mapping trails (which I sincerely hope Telenav doesn't branch out to), things like parks, and adding new roads. If a Telenav mapper later comes along and removes that new/realigned road because it doesn't look like that on Bing, then I guess they'd win again. I'm no longer going to clean up after Telenav, because they don't appear to want a quality map. I'll just have to accept that the routing on my OSM-based Garmin maps will gradually degrade and will likely contain routing issues, so I'll be careful about selecting my own route. 

I used to promote OSM as a great map that had benefits over others like Google, but I'm going to stop doing so because I no longer believe that. Congratulations, Telenav. You've beaten a heavy mapper into submission. You're free to degrade the map in the Victoria area as much as you want, and I won't fight back anymore. 

...at least the Telenav employees still get paid, so someone benefits from all of this in some twisted way... 

Andrew Lester 
Victoria, BC, Canada 

From: m at rtijn.org 
To: "James Mast" <rickmastfan67 at hotmail.com> 
Cc: "OSM US" <talk-us at openstreetmap.org>, "talk-ca" <talk-ca at openstreetmap.org> 
Sent: Wednesday, April 5, 2017 6:00:35 AM 
Subject: Re: [Talk-ca] Telenav mapping turn restrictions 

James — Thanks. This means that at the very least we need to check on a jurisdiction by jurisdiction basis if these turns are allowed or not. 

Just as a data point, Google maps won’t let you make that turn either [1]. That’s not to argue that I am right in any way, just to show that false assumptions regarding turns are made outside of OSM. 

[1] https://www.google.com/maps/dir/40.586229,-80.0446722/40.586796,-80.0438587/@40.5879274,-80.0482634,17.23z/data=!4m2!4m1!3e0 

On Apr 3, 2017, at 9:31 PM, James Mast < rickmastfan67 at hotmail.com > wrote: 

Martijn, that intersection for as long as I can remember, has allowed the right turn @ the intersection and also via the slip lane. The slip lane being closed when StreetView drove by was indeed temporary. They were using it as a temporary staging area for construction vehicles for the bridge they were replacing on Pine Creek Road (well since completed) that was on the other side of the intersection. 


From: Martijn van Exel < m at rtijn.org > 
Sent: Monday, April 3, 2017 1:18:38 PM 
To: James Mast 
Cc: talk-ca at openstreetmap.org ; OSM US 
Subject: Re: [Talk-ca] Telenav mapping turn restrictions 
James -- I could not find any OSC / Mapillary imagery at the location of your example so I took a peek at <<AHEM>> google street view. What I see there is that the slip road / ramp was (as of Aug 2016 -- temporarily?) closed to traffic which may very well inform the allowed right turn at the intersection? Or do you know this to be permanent? In this particular case, based on the info I have, the _link way should have access=no and indeed no restriction would be necessary. (Obviously I can't make those edits because of <<ahem>> above.) 

I'm not saying that there cannot be exceptions to the general rule that 'when there is a turn ramp one must use it', (and as I said before our team is not adding these 'implicit' restrictions until we clear this up). What I am looking for is more clarity (specifically in Canada but in the US also) as to traffic regulations that would make adding these restrictions not only valid but also a boost to the quality of OSM data. I would only want us to add these if there is no confusion regarding correctness and there is added value to adding them. 

I'm cc-ing the US list as there are very similar traffic situations there and I'm interested in clarifying the situation there as well. 



On Apr 3, 2017, at 6:47 AM, James Mast < rickmastfan67 at hotmail.com > wrote: 

Martijn, with your example you gave back 3/30 [1], are you 100% sure that it still might be legal to right turn at the main intersection? It might be if you haven't been there, even with the slip lane being there. 

Case in point, if you were to have one of your mappers modify this intersection [2] with a 'no right turn' relation, you would be adding false information to the OSM database. While there is a 'slip' lane for right turns, there is overhead signage past that slip lane leaving US-19 saying that you are allowed to make a right hand turn at the intersection. So, [3] would be completely legal and would be prevented if a false relation were to be added here. 

This is just something you can't be 100% sure of without visiting it in person, or have imagery from something like Mapillary to see it. So, I can see why Andrew was upset about this. 


[1] https://www.openstreetmap.org/directions?engine=osrm_car&route=40.66610,-111.86760;40.66386,-111.86464#map=18/40.66520/-111.86552 
[2] https://www.openstreetmap.org/directions?engine=osrm_car&route=40.58570%2C-80.04423%3B40.58680%2C-80.04410#map=19/40.58625/-80.04431 
[3] https://www.openstreetmap.org/directions?engine=osrm_car&route=40.58614%2C-80.04461%3B40.58680%2C-80.04410#map=19/40.58648/-80.04457 

From: Stewart C. Russell < scruss at gmail.com > 
Sent: Friday, March 31, 2017 7:26:12 PM 
To: talk-ca at openstreetmap.org 
Subject: Re: [Talk-ca] Telenav mapping turn restrictions 
On 2017-03-31 04:29 PM, Martijn van Exel wrote: 
> … the engine 
> may decide, lacking an explicit restriction, to take the non _link turn 
> because it's faster even if that is an illegal turn. That is why we need 
> these restrictions to be explicit in the data. 

but … but — that's Tagging For The Map, or worse, Tagging To Fix 
Software Stupidity. It's explicitly mapping something that's *not* 
there, and so is contrary to what we're supposed to map. 

I don't have a problem with it being in Telenav's data, but it doesn't 
belong in OSM. 


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