[Tagging] Can OSM become a geospacial database?
fl.infosreseaux at gmail.com
Wed Dec 5 16:31:23 UTC 2018
I don't get the link between geospatial db or not and the difficulties
regarding the local side of tagging.
The same issues can raise on geospatial db as well don't you ?
All the best
Le mer. 5 déc. 2018 à 16:50, Eugene Podshivalov <yaugenka at gmail.com> a
> This email is a forward message of this forum topic
> I guess this topic has been raised may times already but let me add to it.
> Right now OSM is a collection of dots and lines with some generic tags for
> rendering them on a map. They do compile into nice maps but does it really
> work when it comes to searching for objects of real life categories? Let's
> look into some examples.
> * place=city/town/village/hamlet/isolated_dwelling stand for settlements
> of some pupulation ranges. But each country has its own categorization of
> settlements which may absolutely differ from the suggested gradation.
> * waterway=river/stream are used for natural relatively large or small
> waterways. But the notion of river may differ from country to country and
> they may have a much wider range of categories then just these two ones.
> * amenity=school/university/college have some generic notion of secondary,
> higher and further edicution institutions. But again each country has it's
> own categorization of educational institutions and in some cases it even
> contradicts the suggested tag names, e.g. in Russia they have colleges as
> something intermediate between high school and university.
> To wrap it up it is hard to impossible to get objects of some real live
> category from OSM database in order for example to hight light them on a
> map or to list them in search results.
> There are two workarounds used right now. The first one is to bind some
> new tags to local categories e.g. school=high_school, school=college. This
> approach is very contradictary because it is recognized only locally and
> may conflict with notations in other countries.
> The second one is to put category name into "name" tag, e.g. "Liberty
> avenue", "Blue lake", "South park". This approach works pretty fine until
> you think of applying it to everything, e.g. "Manchester" would become
> "Manchester city", all shops would become "[name] shop" and will be
> rendered as such on maps or otherwise additional algorithms will need to be
> coded for rederers to decide whether to cut a category name from the
> displayed name or not for each particular country.
> I invision the following solution here.
> * First of all, the "name" tag should containt proper name only.
> * Secondly, introduce a new tag for the real life language specific
> category name. I know that "name:prefix/postfix" key was originally
> introduced for another purpose but it can be a candidate here as well. Note
> that in some languages the place of category name relative to the proper
> name matters.
> * Thirdly, in order to make the life of renderers simple, introduce one
> more tag for holding the name which can be displayed on maps as is without
> any modifications, e.g. "display_name". This tag may contain whatever
> content is considered locally appropriate specifically for rendering on
> maps. For example, it may contain proper name with category abbriviation
> like "r. Missisipi" or proper name with category full name like "Liberty
> avenue" or if an object has no proper name but is worth being labeled like
> "police station". Locally agreed upon rules should prevail here and if
> somebody needs another format he is free to utilize "name" and
> "name:prefix" tags the way he likes it.
> If proper name is considered good for rendering without any modifications
> like "Manchester" city then display_name can be missing.
> Here are a couple of collective examples:
> * highway=residential + name:ru=Независимости + name:prefix:ru=проспект +
> display_name:ru="пр-т Независимости"
> * waterway=river + name:de=Elbe + name:prefix:de=Fluß (no "display_name"
> tag becase they usually display only proper names of rivers on maps in
> * place=city + name:en=Manchester (no "display_name" tag because it is
> equal to "name", and no "name:prefix" tag if and only if the values in
> "place" tag correspond to the real life settlement categories in US)
> Eugene P
> Tagging mailing list
> Tagging at openstreetmap.org
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the Tagging