[OSM-talk-ie] Multi-part roundabouts (Colm Moore)

[Tony Furnell]

An extra thought on this - I recently found one of the O-shaped "structure"
areas, possibly one of yours Colm, on the northern edge of Derry.
Unfortunately they have an extra foible about them, which is that in iD (my
main editor), there are now rules that stop you saving an edit with an
untagged area. It doesn't appear to include the "note" tag as a *real* tag,
so the O-area didn't make the cut unfortunately :-(

So if continuing with the approach, I guess some extra tagging might be
required - but it then highlights the issue with objects being mapped which
are not really representing data on the ground... not sure how to square
that circle (ho ho).

--
Tony Furnell


On Sun, 24 Apr 2022 at 13:49, Tony Furnell <tonyfurnell at gmail.com> wrote:

> Multi-part roundabouts are a bit of a pet hate of mine too Colm.
>
> I tend to only use a "construction line" temporarily and then delete it
> afterwards, to avoid cluttering the mapping data. My personal preference,
> if it is indeed an option, would be if the roundabouts were not actually
> split - and in the instance of a relation joining and leaving a roundabout,
> the whole roundabout is then tagged with that relation.
>
> It's not outside the realm of reality that say a person following a road
> route by car actually drives around the whole roundabout once anyway, due
> to traffic issues or due to missing the turnoff, but I wouldn't necessarily
> see that as meaning that the driver has left the route - the roundabout is
> after all just a junction, which they join, and then leave. Doing this
> would avoid many instances of relation mistakes wherever edits are made,
> but I don't know what other side effects this may have.
>
> PS: I agree on the administrative boundaries; ideally they should stay
> wherever they were before the roundabout was mapped, usually through the
> centre.
>
> --
> Tony Furnell
>
>
>
>
>> Date: Sun, 24 Apr 2022 07:03:09 +0000
>> From: Colm Moore <colmmoore72 at hotmail.com>
>> To: "talk-ie at openstreetmap.org" <talk-ie at openstreetmap.org>
>> Subject: [OSM-talk-ie] Multi-part roundabouts
>> Message-ID:
>>         <
>> DB4PR10MB61442AF536DEF72A9246817DBDF99 at DB4PR10MB6144.EURPRD10.PROD.OUTLOOK.COM
>> >
>>
>> Content-Type: text/plain; charset="iso-8859-1"
>>
>> Hi,
>>
>> Normally a roundabout is drawn with a single way. However, when relations
>> for say, bus routes or boundaries are added, the way can be split into
>> several parts, as the bus usually will not use the whole roundabout. As
>> there are several parts, using the 'round' tool to make sure the roundabout
>> is circular (if it actually is circular on the ground) is not possible. My
>> previous solution was to add a circle (a 'construction line') to the
>> roundabout nodes, use the round tool and add the following tags:
>>
>> area=yes
>> note=Circle for maintaining shape of multi-part roundabout
>>
>> As there is a certain amount of effort in drawing the circle and making
>> sure it includes all nodes, I have saved the construction lines so that if
>> the roundabout has additional ways added (e.g. for the triangular traffic
>> islands that are common on most roundabouts) or is inadvertently twisted
>> out of shape, the round tool can be used again. Example here:
>> https://www.openstreetmap.org/way/448599590 - this is currently very
>> slightly off circular.
>>
>> An issue arises in that iD thinks that the above tagging is insufficient
>> and now refuses to allow any changes to be saved. JOSM still allows
>> insufficiently tagged objects to be saved.
>>
>> Would anyone have a better solution? There are currently ~102 roundabouts
>> tagged in this way, although there may be others that are still irregularly
>> shaped. As in the recent discussion about attaching landuse to roads, I am
>> not sure that adding a landuse or similar tagging would be appropriate.
>>
>> Thank you
>>
>> Colm
>>
>> PS It is probably best that boundaries go straight through the centre of
>> roundabouts and not follow the roadway - most boundaries were laid out
>> before roundabouts existed.
>>
>>
>>
>> ---------------------------------------------------------------------------------------------------------------
>>
>>
>>