I do still use tertiaries and above for higher level roads in accordance with the Highway Tag Africa scheme. I was merely giving an example of how I classify a service road.
-AndrewBuck On 11/14/2017 09:48 PM, Pierre Béland wrote: > From discussions since 2013 with various african OSM communities and other > continents with similar realities, it appears that this wiki page is quite > usefull to help classifiy the highways in these countries. > The objective was to simplify, clarify how to tag highways. Adding pages by > country would not faciliate the task, would add confusion. > About Andrew proposition, I dont understand why to use the hierarchy set > (residential, service) instead of (tertiary, residential). With such > classification, there is nothing between motorways / primary and residential > highways. > > Pierre > > > Le mardi 14 novembre 2017 22:10:38 HNE, Gaurav Thapa > <gthapa.w...@gmail.com> a écrit : > > Youthmappers initiative actually has a very large presence in Africa and in > particular local mappers of Ghana, Uganda and Nigeria are very active. They > don't use the talk pages but maybe we can bring them on board to improve > > https://wiki.openstreetmap.org /wiki/Highway_Tag_Africa > > or create country specific pages. > > On Wed, Nov 15, 2017 at 4:15 AM, Andrew Buck <andrew.r.b...@gmail.com> wrote: > > Pierre's suggestions are a good guideline in general and I don't have > any disagreements with them. > > I did, however want to expand a bit on the idea of when to use service > roads, so here is that... > > I for one am in favor of additionally making liberal (but careful) use > of highway=service. > > A service road is like a residential road, but is not meant to be used > for "through traffic" but rather as the first or last leg of a longer > journey. With this in mind, I offer up the following example as a good > guideline (or case study) of how this should look in practice: > > Several years ago, I traced the roads in Ibadan, Nigeria. It was nearly > a blank map when I started so I had complete freedom in deciding how to > classify them (this was years before "highway tag africa"). I started > by just marking nearly everything as highway=residential. Then after > the whole city was mapped I spend some time just looking at the finished > map and the roads overlaid on the satellite imagery. After taking in > this "whole city view" for a while I began to see patterns in how the > roads were laid out, and these patterns suggested which roads should be > downgraded to service. > > In the case of Ibadan there are little "pocket communities" of people, > separated by streams with a few roads crossing the streams but a dense > network within each community. So after digesting the map, and seeing > how the town was structured, I decided I would downgrade all the roads > that only served to access buildings within one community, but were not > part of the routing if you were traveling outside of the community. > This lead to a marked improvement in the quality of the map, which you > can see in the two links below. Although I finished tracing all the > roads, I didn't finish all the classifications, so you can see a good > "before and after" of how much better it looks with proper use of > service roads. > > Here is a "before" section where all the roads are left as residential: > > https://www.openstreetmap.org/ #map=15/7.3354/3.9118 > > And here is an "after" section where I have downgraded local-access-only > roads to service but left the rest as residential. Notice how much more > clearly you can see the neighborhoods, and also how much easier it is to > follow a route, without having to use a route planning tool. You can > navigate just by looking at the map. > > https://www.openstreetmap.org/ #map=15/7.3933/3.9598 > > In the second example above you can actually see some areas of all > residential to the east, so there is a very clear difference between the > two sections. > > Obviously every town will be slightly different, but I think this is the > general rule we should follow: > > if you use the road mainly for accessing buildings (even if it is > a fairly large number of them) but not for long distance travel, > then the road should be downgraded to service. > > After you spend a bit of time looking at the whole town, and keeping > this rule in mind, you will get a good sense of what to downgrade. Then > it is just a matter of going through and applying it. > > Anyway, hope this all makes sense to people. I had been meaning to > write it up for a while now and this seemed like a good opportunity. > Maybe I will try to go through and finish up Ibadan, I am a lot faster > at this now than I was back then, so it wouldn't take me long. I will > leave it for the time being so it doesn't break the examples. If people > think this sounds reasonable, maybe we should grab some before and after > screenshots for the wiki to document this. > > -AndrewBuck > > > > > On 11/14/2017 03:30 PM, john whelan wrote: >> That seems very sensible. >> >> Thanks John >> >> On 14 November 2017 at 16:26, Pierre Béland <pierz...@yahoo.fr> wrote: >> >>> I we follow the Highway Tag Africa wiki page I initiated in 2013, narrow >>> highways should be evaluaed on the type of traffic possible >>> - highway= residential in residential areas if at least passable by 4 >>> wheels >>> - highway=path if only motorcycles, bicyles and foot traffic is possible. >>> >>> https://wiki.openstreetmap. org/wiki/Highway_Tag_Africa >>> >>> The additions made to the wiki page a few months ago about the width add >>> confusion. I think that we should simply move this in a separate section >>> giving guidance on possible widths that represent the various types of >>> highways. >>> >>> regard >>> >>> Pierre >>> >>> >>> Le mardi 14 novembre 2017 16:14:22 HNE, john whelan <jwhelan0...@gmail.com> >>> a écrit : >>> >>> >>> I'm not even sure if this is the best place to raise this but Africa >>> covers a lot of countries. >>> >>> We have some agreement on how to map highways in general Africa but narrow >>> residential highways are a problem. I suspect highway=residential plus a >>> width tag might be best. >>> >>> South Africa I think has local mappers who able to resolve any problems >>> but for the rest of Africa given the large number of armchair mappers >>> mapping there some guidance would be nice. >>> >>> Some mappers use highway=service generously. >>> >>> Is it possible to reach some sort of general concenus? >>> >>> Thoughts? >>> >>> Thanks John >>> ______________________________ _________________ >>> talk mailing list >>> talk@openstreetmap.org >>> https://lists.openstreetmap. org/listinfo/talk >>> >> >> >> >> ______________________________ _________________ >> talk mailing list >> talk@openstreetmap.org >> https://lists.openstreetmap. org/listinfo/talk >> > > > > ______________________________ _________________ > talk mailing list > talk@openstreetmap.org > https://lists.openstreetmap. org/listinfo/talk > > > > >
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