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Some Progress to my WMA Edits

Posted by BioDP2 on 27 May 2022 in English.

To the Three Commenters who provided feedback to yesterday evening’s Diary post: “Thank you!”

It feels a bit counterintuitive, but I am not overly familiar with Social Media. I haven’t logged in to Facebook in over 4 years… I’m on a computer all day, and the last thing I want to do when I get off work is stare at another screen. That being the case, I am surprised at the speed of replies to my post. :)

And thank you for the recommendation of “Key:protect_class” ~ Looks like what I was needing!

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GeoJSON

So, it turns out that JOSM can read JSON files. (Yay!) But it is not happy if I try to import a multipart polygon from a JSON file. And I really don’t want to make the OSM Community or JOSM unhappy.

So I built a little model in ArcGIS last night. It steps through my WMA boundaries feature class, splits multipart polygons into single part polygons, and transforms the latter into GeoJSON files projected into WGS_1984. There’s some fancy renaming too (honestly, it isn’t very fancy, but it keeps the output from being a total mess).

I now have GeoJSON files for 407 singlepart polygons. The 4 representing Broken Bow WMA have already been used to replace my hand-digitized attempt from earlier in the week.

Worries

My current worries revolve around topology.

  • Areas managed by my Agency don’t always match up with other areas’ boundaries by conscious/cooperative design

Within my Agency, we use a Conformal Conic projection (NAD 1983) since it minimizes area/shape warping, and keeps distances comparable. But even when I reproject my data to Web Mercator, it doesn’t match up well to other’s boundaries even when that is expected.

See full entry

Location: Stillwater, Payne County, Oklahoma, United States

To whomever is reading this, my apologies.

I work for my state’s Dept. of Wildlife Conservation, and help make maps of agency-managed lands for public use. I’ve noticed a few projects geared towards community-development of basemaps.
At a recent Division-wide meeting, one of the Field Biologists brought up that they were surprised to find one of the WMAs (Wildlife Management Areas) depicted in an online vector basemap. At which point, I decided that I needed to take it upon myself to add/update our areas in those community-driven basemap projects.

I began by using the osm.org basic iD Editor. I was surprised to learn that shapes could not be imported directly. But happily began playing “connect the dots” with gpx files rendered from my shapefiles’ vertices.

We use Esri tools, so I made use of Dan Patterson’s “Poly* features to points” tool to create numbered points for each WMA.

This was okay for the first week.

I found myself losing patience with all those dots… Why couldn’t I trace another editor’s lake boundary? Why are this area’s boundaries linked to the roads? Why is this one area treated as two… is it not possible to dissolve them into one area along the shared boundary?

I don’t want to anger the rest of the OSM Community, but nor do I want to spend the rest of the month connecting the dots over some million-and-a-half acres and fiddly boundaries along man-made reservoirs.

So I found JOSM. It is horrendibly confusing to me, but I hope to get it right. …I note there is a ‘trace other feature’ tool. ^_^

See full entry

Location: Stillwater, Payne County, Oklahoma, United States