[Tagging] Sidewalk Tagging for Routing

[Bryan Housel]

Current preference seems to be map sidewalks as separate ways tagged as `highway=footway + footway=sidewalk`.

1. As you mentioned, you can use sidewalk-specific tags (slope, surface) without affecting the adjacent highway.
2. The sidewalk and the road really are separate features.
3. New users like to trace and they are going to map it like this anyway.
 
I don’t really buy the “mapping sidewalks as part of the road makes routing easier" argument, but I don’t work on routing software so maybe there really is something complicated about routing that I am unaware of.



> On Nov 23, 2015, at 6:03 PM, Clifford Snow <clifford at snowandsnow.us> wrote:
> 
> I'm working with a local non-profit to tag sidewalks for wheelchair [1] accessibility. Tagging sidewalks is usually done by either drawing in a new way and often parallel to roads or tagging the highway with sidewalk=left/right/both/none. Either of these produce acceptable results for normal walking. My questions concern tagging the wheelchair slope. Tagging slope when the sidewalk is tagged with highway=footway, footway=sidewalk is pretty straight forward. Novices can be easily trained to tag sidewalks this way. One of the issues with this arrangement is routing the other is it adds to the number of features. 
> 
> The other method, tagging sidewalks as features of highway=* would appear to make routing much easier. Adding in tags for the kerb (curb) slope start to increase the complexity. A typical tag for slope is sidewalk:right:sloped_curb:start. iD can handle this tag by manually entering the tag, but it increases the complexity to teach new mappers. There is also the problem when a city decides to save money by adding the slop the the corner of the intersection. Instead of 8 cuts, they only have four. Taginfo only has 175 slopes [2]  tagged. 
> 
> My goal is to provide a simple method to train novices to add sidewalks and kerb ramps. 
> 
> I would be interested to hear your thoughts on how to approach this problem.
> 
> Clifford