[OSM-talk] Separate lane tagging

[LM_1]

I somehow forgot to react on this one.

2012/3/5 Martin Koppenhoefer <dieterdreist at gmail.com>:
> Am 5. März 2012 12:08 schrieb LM_1 <flukas.robot+osm at gmail.com>:
>> Currently the recommendation about separate mapping of directions
>> seems to be the existence of a physical divider (wall, grass...).
>>  There is no problem if the divider is continuous and only has
>> 'holes' in it to allow turning or lane changing during construction
>> works.
>
>
> when there are "holes" you will obviously have to split the divider
> and keep the holes free.
>

Sure, this question was not about dividers, but about the streets around.
>
>> If the divider is only a small object like tram platform, it does not
>> seem right to divide the way and connect it afterwards.
>
>
> why not? IMHO you should so exactly this. There are also similar
> situations like subway entrances and pedestrian crossing islands where
> the carriageway is split.
>
>
Not, because it seems like the road is curved, while it is not (or
very little).
>>  If this is mapped according to the recommendation the street would
>> be between two rails (trams cannot change rails), which is not true.
>>  If each of the one way general traffic roads is mapped separately,
>> it would seem that you cannot turn (you are not allowed to, but it is
>> physically possible).
>
>
> This whole "physically possible" field merits some further
> considerations and discussions IMHO. First of all: physically possible
> for whom? An old lady with a stick? A battle tank? A generic young
> male acting as pedestrian? Possible with a vehicle with 2 axes 4
> metres long and 1.8 wide or one 18 metres long and 2.3 metres wide?
> Would a cyclist dismantle and lift his bike over a small fence to
> avoid 3 km of detour? Would you risk damaging the tyres of your car
> (could still be "physically possible") or do you prefer not to? This
> all depends on a lot of different factors.
>
In this case physically possible for all the examples you mentioned.
The road has almost same surface quality across the whole width, the
only thing that is stopping you is a white line.
Adhering to the rules creates completely misleading results and
ignoring them by tagging the current legal situation makes physically
connected way look like a street with separated directions...
>
> For instance some time ago some mappers started to use
> highway=footway, footway=sidewalk to map sidewalks with dedicated
> osm-ways. This will in many cases actually lead to worse routing
> results, as a destination just on the other side of the road will make
> your router suggest to go via the next crossing (however far that
> might be), instead of telling you that you have already arrived.
>
>
> cheers,
> Martin
LM_1