[Tagging] Feature Proposal - RFC - Sidewalks as separate ways

[Serge Wroclawski]

On Thu, Mar 24, 2011 at 4:15 PM, David Paleino <dapal at debian.org> wrote:
> Hello everybody,
> as promised, I came back with an "official" proposal.
>
>  http://wiki.openstreetmap.org/wiki/Proposed_features/Sidewalk_as_separate_way

"In particular, for blind people, it's important to have precise
information when walking: to understand on which side of the street
they are, for example. This is not possible when just adding tags to
the main way -- a separate way ought to be mapped."

My general frustration with your RFC is that it reads more as a stance
than a proposal. I think that this issue of the blind, for example, is
a bit of a false dichotomy, because the issue of sidewalk direction is
handled in both methods"

One can take exactly the opposite stance, which is that in order to
help the blind, we should make it as easy as possible to map things
that they care about. Therefore a sidewalk=yes tag would be the
fastest way to get the maximum data into the map.

This is especially important when talking about rendering and routing,
which I think are the main use cases of this tag. Your proposal only
casually mentions relations, but they're extremely important without
the main road data (see later in this mail where I go into detail
about this).

But even so, I don't really care what method is used, but I think the
proposal should be more factual and less ideological, even (and
including) removing emphasized words such as "However" and removing
emoticons.

> I tried to summarize what my ideas are, and why I don't believe that tagging
> the main road is any good.
>
> To summarize here: to tag a sidewalk:
>
>  * highway=footway
>  * footway=sidewalk

Later in this thread, David, you asked for a clarification of the term
"real world" by another mapper. Humor of that question not
withstanding, I believe the other mapper was reacting to the fact that
we already have a great deal of difficulty getting casual mappers to
work with our system. We've mitigated some of these issues with
helpers like preset menus.

With sidewalks as a separate way, you are now stuck with two unoptimal
situations:

a) The sidewalks have no road-associated data

The sidewalks not having street data is, IMHO, a significant problem.
It means that while it might be possible to get highly accurate
routing directions in the sense of "turn right in 30 meters", you will
lack information such as "Walk up Main Street".

This is bad for everyone.

b) There is a relation

Relations are a powerful tool, but they're hard to work with. They're
hard for renderers to work with (say those who render), they're hard
to make work correctly in the editors (say the editor authors) and
they're hard to work with, and even harder to teach others how to use.
I know, I've done it.

In this specific instance, your proposal lacks a relation example, or
even the recommended relation type that should be used. Looking at the
relation page: http://wiki.openstreetmap.org/wiki/Relation

I don't see a relation that fits. Can you provide an example which
answers these basic questions?

Generally, I think this proposal seems to be more of a reaction.
Personally, if people want to map sidewalks, I don't care about the
method. This way may be more technically correct, but after having run
mapping parties and taught mappers, I think we need to encourage
simplicity.

- Serge