[talk-au] Ferry Routes mapping in NSW

Sigurjón Gísli Rúnarsson sjonni11 at gmail.com
Mon Nov 26 00:43:27 UTC 2018


Hi all,



I have had some recent feedback regarding my changes to the ferry route
paths in Sydney Harbour in August this year.  I basically changed the
mapping from single way approach to relation approach.  The main reason for
this change was so that the ferry route paths could be used for routing
purposes, to reflect what is actually happening on the “ground” with these
ferry route services.



The feedback I received from the OSM user is that these ferry routes should
be mapped back to single way approach as having ways intersecting/branching
between terminals/wharves should not be allowed. Rather, there should only
be a single way between wharves.  At the moment some routing engines take
turns in the middle of the harbour (example
<https://www.openstreetmap.org/directions?engine=graphhopper_foot&route=-33.8471%2C151.1852%3B-33.8385%2C151.1760#map=16/-33.8434/151.1907>
– now fixed in database) which I agree is not ideal.  I have tried to map
the ways to avoid this as much as possible.



I feel that I’m following the wiki
https://wiki.openstreetmap.org/wiki/Tag:route=ferry with the relation
approach.  At the time that I made the changes, I got only minimal (all
positive) feedback regarding my approach to this.  But I can also
understand the reasoning behind why the single way approach is preferred,
as it looks better from a cartographic point of view on the standard OSM
map tiles and gives a good overview of the ferry routes.



Unfortunately mapping with the single way approach does not give options
for accurate routing based on the way the actual ferry services operate.



The idea was brought forward to apply custom tagging to the “new” ways that
have been mapped based on the relation approach.  These custom tags (i.e.
route=[custom tag]) could then be used in conjunction with single way
approach ways for routing based on services.



I am not saying this is ideal, but I am willing to look at any compromise
that could be perhaps suit everybody.



So my question is, is it possible to tag with custom tagging (i.e.
route=ferry_services) or any of the existing tags
https://taginfo.openstreetmap.org/tags? That would mean that routing
engines like graphHopper could keep using the route=ferry for it’s ‘A’ to
‘B’ foot routing.



I think that moving forward, there will be the need for relation approach
(routable) ferry route paths.  App devs and transport agencies will have
need to use these ways for routing. Obviously, this is my opinion, so I
would really appreciate your views on this.



Thank you



On Mon, 6 Aug 2018 at 23:42, Andrew Harvey <andrew.harvey4 at gmail.com> wrote:

> I think so long as there's an active ferry route running between two
> terminals then it should have a route=ferry[1] connecting them, roughly
> following the actual geometry the route normally takes. Where you have a
> ferry route that sometimes has a few variants, eg. sometimes skips a
> terminal, or sometimes goes to a different wharf, then that can be
> accounted for using the ferry route relation.
>
> As the wiki points out[1], this could be a simple way, or a route
> relation[2]
>
> [1] https://wiki.openstreetmap.org/wiki/Tag:route%3Dferry
> [2] https://wiki.openstreetmap.org/wiki/Relation:route
>
> On 6 August 2018 at 23:20, Sigurjón Gísli Rúnarsson <sjonni11 at gmail.com>
> wrote:
>
>> Hi,
>>
>>
>> I would like to amend the Ferry routes in NSW, particularly in and around
>> Sydney using a different approach.
>>
>>
>>
>> At the moment the Ferry routes are mapped with a *single way approach,*
>> by tagging a single way drawn along the whole route (i.e. Circular Quay
>> to Manly).  The only benefit for the single line approach, that I can see,
>> is that it is simple and represents well on the map tiles.  The problem
>> with this approach is that it does not allow ways to share different routes
>> and or variants.
>>
>>
>>
>> That’s where my particular problem lies.  When I try to generate route
>> paths from GTFS Sydney Ferries and private ferries (TfNSW) using the OSM
>> Ferry route paths as the routing network, a lot of errors occur.  Many
>> variants/trips in the GTFS dataset, which are based on recent timetable
>> information from Sydney Ferries and other private operators, have no
>> routing options.  This is because of the single way approach between
>> wharves.
>>
>>
>>
>> For example, F4 Watsons Bay – Pyrmont via Rose Bay and Circular Quay: To
>> go from Rose Bay to Circular Quay the routing takes you around the harbour
>> (Taronga Zoo, Milsons Point, Balmain and Darling H) before getting to CQ
>> Wharf 5.  Instead, there should be a direct route displayed between Rose
>> Bay and Circular Quay
>>
>>
>>
>> Another example is that one ferry service might use wharf 5 at Circular
>> Quay, but 20% of the trips/variants might use wharf 4. Those 20% of
>> trips/variants will not route to and from the correct wharf using the
>> single way approach.
>>
>>
>>
>> To be able to use the OSM Ferry route network for routing using GTFS
>> files from TfNSW, I want to map based on the *relation approach*.  Just
>> like other transport modes are being mapped in OSM (i.e. bus routes).
>>
>>
>>
>> This would mean that more than one ferry route could share some ways,
>> enabling users to extract OSM ferry routes to use for routing.
>>
>>
>>
>> I would like to get thoughts from OSM users on this approach before I
>> start mapping in such way.
>>
>>
>> Regards,
>>
>> Maradona11
>>
>> _______________________________________________
>> Talk-au mailing list
>> Talk-au at openstreetmap.org
>> https://lists.openstreetmap.org/listinfo/talk-au
>>
>>
> _______________________________________________
> Talk-au mailing list
> Talk-au at openstreetmap.org
> https://lists.openstreetmap.org/listinfo/talk-au
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/talk-au/attachments/20181126/f87227fd/attachment.html>


More information about the Talk-au mailing list