> In my usage, i always thought that using a barrier=* + any other main tag was > wrong...
I agree that this usage is ambiguous. However, that usage is very common, and is suggested on Key:fenced: https://wiki.openstreetmap.org/wiki/Key:fenced - "Whether the outer perimeter of something is fenced." "This feature has been labeled as deprecated. The recommended replacement is: barrier=fence." "Once upon a time there were no barrier tags, because nobody had invented them yet. In that time the only way to map a fence in Openstreetmap was with fenced=yes. Almost all fences mapped since the invention of barrier=fence are (re)mapped using that new tag." Since the original mapping was to add "fenced=yes" to "landuse=meadow" or "leisure=playground", it is still very common to add 'barrier=fence' to one of these features, and by analogy this is also done with walls, hedges and other barriers. According to http://overpass-turbo.eu/s/Qr1 there are 36k closed ways with barrier=hedge + area=yes without another area feature, but there are 16k uses of `barrier=hedge` + another tag which describes an area: http://overpass-turbo.eu/s/Qr3 The situation is worse for `barrier=wall` and `barrier=city_walls`: there are over 98k ways with `barrier=wall` and another tag which defines an area (like leisure, landuse, amenity etc: http://overpass-turbo.eu/s/Qr4), compared to under 12k ways with `barrier=wall` but without one of those other tags. While the average wall is thinner than the average hedge, the difference is less than an order of magnitude, and there is another feature that is about as wide as a hedge: `barrier=city_wall` - which is also sometime mapped as a area. But there are only 787 of these ways with `area=yes` (http://overpass-turbo.eu/s/Qr6) versus 1800 barrier=city_wall ways which are combined with a polygon feature tag like landuse=* (not including historic=citywalls) - http://overpass-turbo.eu/s/Qr8 This means that if mappers want to use barrier=hedge and barrier=wall and barrier=city_wall for both linear features and areas, database users are going to have to look for tags like area=yes and type=multipolygon to try to figure out if it is a linear or area features, and often there will be mistakes The Netherlands has been claimed as a place where barrier=hedge areas are used properly and are necessary. I have already downloaded one whole provicne, Zeeland, which has quite complete landcover and landuse mapping due to an import. In Zeeland there are 149 uses of `barrier=hedge` on a closed way without `area=yes` or landuse=, natural= or leisure=, and only 12 closed ways with `barrier=hedge` + `area=yes`. I checked some of the former and all of the later, and it appears that the local mappers have treated both the same ways: 1) as an alternative to mapping thin hedges as a single line 2) as an alternative to mapping tree rows as a natural=wood or landuse=forest area 3) to map areas of bushes around farms or residential areas, which are perhaps more of a "shrubbery" than a proper "hedge" - often these are patches of bushes rather than a linear, barrier-like feature But in most areas, you will find similar features tagged with `landuse=forest` right next to the `barrier=hedge` closed ways. The tag natural=scrub for areas of bushes seems less common in the Netherlands than in some other countries, so perhaps the barrier=hedge areas are being used as an alternative. I will discuss these particular examples further at github where I can post images (see. Also please discuss the particular Openstreetmap-carto rendering issues there (https://github.com/gravitystorm/openstreetmap-carto/pull/3844), after reading through the relevant history. We did try just rendering hedges with area=yes first, but this did not work: https://github.com/gravitystorm/openstreetmap-carto/pull/3834 - read this first. Here on this mailing list we should try to focus on how to tag and map things. For example, perhaps someone can make a reasonable proposal for how to map small areas of pruned and trimmed bushes and shrubs: often these are currently mapped as natural=scrub or leisure=garden, but perhaps a new, more specific tag would be better? The natural vegetation tags like natural=scrub, natural=heath and natural=wood could also be improved by additional property tags which described the density of the vegetation (e.g. are there wide gaps between the tallest plants, or is there a continuous canopy?). It could also be considered to go back to using `fenced=yes` along with `walled=yes` and `hedged=yes` as a "property tag" to go with a feature like a playground or meadow, but this would require a huge amount of re-tagging. What doesn't make sense is trying to use the same tag to describe a linear feature like a road, barrier or waterway, and also for the area of that same feature. In all other cases we use a different tag for the area: * waterway=river + waterway=riverbank * highway= + area:highway= * railway= + landuse=railway - Joseph Eisenberg On 2/6/20, Lionel Giard <lionel.gi...@gmail.com> wrote: > In my usage, i always thought that using a barrier=* + any other main tag > was wrong and widely accepted (as i saw that it was separated in most > examples when i started mapping). Thus my method has always been to map > them separately (one way for the barrier and one way for the other main > tag, even if they are exactly sharing the same node). This is in order to > keep the one feature to one object and keep things manageable and without > ambiguity. Thus to me, all the examples of "barrier=*" (+ "area=yes" +) > "leisure=playground" are a tagging error, that should be two separate > objects. > > If it is a tagging error, then we don't need to remove the rendering, it > just need to be corrected on the data side by mappers. Am i wrong in > thinking that ? > > Le mer. 5 févr. 2020 à 22:43, marc marc <marc_marc_...@hotmail.com> a > écrit : > >> Le 05.02.20 à 22:08, Christoph Hormann a écrit : >> > (either 'invalid', '1d barrier' or '2d barrier'): >> >> Here is my view AND I known that osm consensus is not that : >> >> > closed way, barrier=fence >> >> 1d barrier >> >> > closed way, barrier=fence, area=yes >> >> 2d barrier >> >> > closed way, barrier=fence, leisure=playground >> >> bad idea >> >> > closed way, barrier=fence, leisure=playground, area=yes >> >> 2d barrier >> >> > multipolygon, barrier=fence >> >> 2d barrier >> >> > multipolygon, barrier=fence, area=yes >> >> 2d barrier >> >> > multipolygon, barrier=fence, leisure=playground >> >> 2d barrier >> >> > multipolygon, barrier=fence, leisure=playground, area=yes >> >> 2d barrier >> >> > closed way, barrier=hedge >> >> 1d barrier >> >> > closed way, barrier=hedge, area=yes >> >> 2d barrier >> >> > closed way, barrier=hedge, leisure=playground >> >> 2d barrier >> >> > closed way, barrier=hedge, leisure=playground, area=yes >> >> 2d barrier >> >> > multipolygon, barrier=hedge >> > multipolygon, barrier=hedge, area=yes >> > multipolygon, barrier=hedge, leisure=playground >> > multipolygon, barrier=hedge, leisure=playground, area=yes >> >> all : 2d barrier >> >> > closed way, barrier=ditch, waterway=ditch >> > closed way, barrier=ditch, waterway=ditch, area=yes >> > closed way, barrier=ditch, waterway=ditch, leisure=playground >> > closed way, barrier=ditch, waterway=ditch, leisure=playground, area=yes >> >> all : same as for barrier=hedge >> _______________________________________________ >> Tagging mailing list >> Tagging@openstreetmap.org >> https://lists.openstreetmap.org/listinfo/tagging >> > _______________________________________________ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
