OpenStreetMap

#DigitizeRacine begins!

Posted by jcarlson on 1 October 2018 in English.

A lot of the counties around here provide publicly available building footprints. Mine doesn’t. Inspired by some of the more rigorous OSM efforts that exist in the broader community, I am committing myself to my home community of Racine.

Beginning with the City around me and broadening out, I’m going to work on getting all our buildings added to OSM, and fix some of the validation errors lurking in the data. Seems our local editors like to combine landuse ways with highways, but the common convention is that this is incorrect. Lots of ungluing to do. Other things, too.

An effort like this needs its own hashtag, I think. So: #DigitizeRacine

We’ll start with rough building footprints, just to get everything on the map. Later, house numbers, porches, more specific tags, all that. But for now, I’m just going to churn out some rectangles.

Edit: also seems that the landuse areas will, at their corners, follow the curb. But why follow one curb and say “landuse doesn’t include the street”, and then completely cover whole swathes of other streets? I’m going to break them up into block-sized areas. I’m of the opinion that this is more information, too, as it gives the actual curb locations.

Location: Racine, Racine County, Wisconsin, United States

Discussion

Comment from escada on 3 October 2018 at 09:15

I wonder why you consider the sidewalks as landuse=residential (and the road not). If you split up the landuse, it should end at the building. The sidewalks and roads belong to a “landuse=road” which is mapped as area:highway.

Considering the border of landuse=residential as kerb is something I haven’t heard before.

What many mappers do is indeed to have 1 landuse polygon going over roads if the usage stays the same, but let the landuse end outside the road/sidewalk/road side when it is different on both sides of the road. I only know a handful of people that go in more detail and always let the landuse end at the road side. (not the kerb).

Comment from LeifRasmussen on 3 October 2018 at 12:49

By the way, area:highway should not include sidewalks, just the street.

Comment from jcarlson on 3 October 2018 at 14:16

@escada A fair point. I’ll update my areas to end at the sidewalk, to be more in keeping with the parcel boundaries. I’m still of the opinion that each block should have its own area, however. To me, it doesn’t make sense that a landuse area would end at one street’s edge (implying that there is an important distinction), but then cover over other streets entirely (implying the opposite).

As @LeifRasmussen points out, highway areas are street-only. There’s no obvious landuse tag for that right-of-way strip between the parcel and the street, but that’s beyond the scope of what I’m doing at the moment.

Comment from escada on 3 October 2018 at 14:20

@LeifRasmussen not true: see https://wiki.openstreetmap.org/wiki/Key:area:highway and https://wiki.openstreetmap.org/wiki/Proposed_features/area_highway/mapping_guidelines

they are mapped as separate area:highway’s from the road area, but still as area:highway

Comment from jcarlson on 3 October 2018 at 14:27

Ah! Thank you for the link. I was confusing “area:highway” with some of the discussions about “landuse:highway”.

Comment from LeifRasmussen on 3 October 2018 at 14:52

@escada that is correct. What I meant was that area:highway=residential should not include sidewalks, grass, and other features not on the street but inside of the easement. Separate area:highway features can be used for sidewalks.

Comment from LeifRasmussen on 3 October 2018 at 14:56

By the way, Microsoft has released building footprints for the entire US that can be imported into OSM. Importing them might be a fun project to do in your county if you’re interested.

Comment from jcarlson on 3 October 2018 at 15:52

@LeifRasmussen Thanks for telling me! I’ll check it out.

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