[Talk-us] Fwd: Sidewalks as footpaths

[Serge Wroclawski]

Bill,

You're right that we should map what exists on the ground. I think we
need to really consider a few factors here:

1. Why we map sidewalks at all (in either style)
2. What benefits one mapping method has over another
3. The data as it exists now

1. Why map sidewalks

This is a judgement call. In NYC it's reasonable to assume that a road
has a sidwalk. It would be better to map roads without sidwalks than
roads with them, because a vast majority of roads have sidewalks.

In DC, where I used to live, many roads did not have sidewalks, or
only had sidewalks on one side of the street.

Maybe where you are, it's closer to DC, or possibly even less. Or
maybe you are trying to bright some light on the state of sidewalks in
your area.

2. Benefits of one mapping method over another

I think we've beaten this topic to death, not only on this thread, but
several times in the past on this and other lists. Benefits of
sidewalks as attributes: simplicity (which often wins in OSM).

Benefits of mapping them as separate ways: Potentially more data about
quality, breaks in the sidewalk, etc. Downsides: Routing engines can't
know what sidewalk is associated with what street.

Benefits of using relations is that it gets around the routing
problem, except that AFAIK no router does that.

3. Usage

The biggest issue here is usage. It's not "what mappers should do",
but "What mappers actually do" and what mappers actually do is not to
create relations. Most sidewalks are either mapped as separate ways,
as attributes, or not at all.

That's why I'd prefer it to be made as easy as possible for them.

Ultimately this is a decision people can make for themselves. I'd
rather they map than not map, but certainly people have their own
ideas on how people should represent things.

- Serge