[Talk-GB] Paths and Footways
ajt1047 at gmail.com
ajt1047 at gmail.com
Sun Aug 16 19:06:20 UTC 2015
On 16/08/2015 18:26, Rob Nickerson wrote:
> Hi all,
> Given that paths and footways are now rendered the same way in the
> default OSM style I wonder whether it is time to look at how the map
> can provide better information.
> For rural mappers tagging a path/footway as unpaved surface results in
> it having less prominence on the map. As most major public rights of
> way are unpaved this makes these paths harder to view on the default
> OSM map.
> Some possible changes:
> 1. Render all paths/footways that are tagged as
> designation=public_footpath (or other RoW) more prominently.
Are we talking about OSM-Carto here? That's by definition an
international style and I don't think that rendering
designation=public_footpath outside of England and Wales makes a lot of
sense, although it would make sense as a "local style" for England and
Wales (you've mentioned that as a possibility recently). I don't know
how far the "core paths" network in Scotland has progressed either on
the ground or in OSM, but perhaps some variant based on that could work
> 2. Render those paths/footways that make up a long distance walking
> route more prominent (relation data).
That makes some sense, but OSM-Carto's biggest problem is that a number
of the changes over the last year have been dedicated to making
well-mapped central European urban areas "look nice" at the expense of
the rest of the planet. There's a lot more that would have to be done
to make OSM-Carto usable for e.g. rural footpaths outside cities.
There's chapter and verse already in github issues (including "not
rendering foot=yes access=private ways at some zooms" and "not rendering
major landscape features such as abandoned railways"), so no need to
repeat here, but a lot of the last year's changes would need to be
reversed to make the style usable for that purpose. This doesn't make
the changes "wrong" or "bad" of course; every map style has to decide
what to show and what not to show - try and show everything and you end
up with a complete mess.
> 3. Render based on another tag such as trail visibility  or maybe
> we need a brand new tag to indicate path dominance (like we have
> motorway/trunk/primary/etc for roads).
I'm not sure there's "room" in the presentation of footway etc. for
this. I do render (using a modified style based on osm-carto from some
time ago*) designation and width, but do throw
footway/bridleway/cycleway/path into the same bucket.
http://imgur.com/JQGc0YR is an example of that (compare with
http://tile.openstreetmap.org/13/4061/2663.png ) - red means "public
footpath", blue means "bridleway", grey means "no designation"; and dots
mean "narrow" and dashes mean "wide". I suspect that trying to display
the many values of trail_visibility would be difficult or impossible
(and what should be the default value where it is not recorded?).
One approach (if we're just talking about raster tiles here) might
involve transparent overlays**, though that means even more data
downloaded over what is likely to be a dodgy cellular data connection if
you're in the middle of a field. If we're not (and if we're not
starting from OSM-carto, we don't need to) then other people have
already suggested something else entirely***.
* See https://github.com/SomeoneElseOSM/SomeoneElse-style and
https://github.com/SomeoneElseOSM/openstreetmap-carto-AJT . I'm not
suggesting this is a "style for all rural map users" of course (it'd be
rubbish for cyclists, for example). It's just included as an example of
the problems of displaying yet more different elements in the data.
** Like the Met Office use on their OpenLayers site (but better than
*** The author of http://blog.systemed.net/post/13 for one.
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