AlaskaDave has commented on the following diary entries

Post When Comment
A Mapper in the Spotlight: Dave Swarthout (USA/Thailand) 2 days ago

@bdiscoe Wow, good work! Adding riverbank to the "Big Su" is a huge job. I didn't want to tackle it until I was back there next summer. I just read through your diary entries and came away quite impressed. I've often wanted a way to automate drawing roads and tracing lakes and it looks like you've been working on writing some code to accomplish that. I began using FastDraw some time ago but was disappointed with how savagely it reduced the number of points when simplifying. But after some help from more astute mappers I learned how to control it better and am using it much more now. But a fully automatic lake tracer would be a huge help in mapping Alaska's vastness. Maybe you're the guy who will do that. (I'll be keeping my fingers crossed.)

Seriously though, thanks for the help. I see you spend a good deal of your time in Hawaii but I wonder if you are someone who likes Alaska or wants to visit. If you ever get there in the summer months, drop me a line. I live in Homer, one of the prettiest places on earth. I did most of the Tiger work there, corrected names, verified highway data on the ground, etc. I'm trying to add landuse features on the Kenai Peninsula but for the moment am limiting myself to just what can be seen from the highway. There is simply too much area for one person to take care of!

A Mapper in the Spotlight: Dave Swarthout (USA/Thailand) 11 days ago

Hi javbw, thanks for the nice comments,

I started out in Thailand as a motorcycle enthusiast. This country has some of the best roads for motorcycling; it's got to rank among the best in the world, especially if you take into account how cheap it is to tour here. A nice hotel costs about 15-20 USD and the food is both delicious and cheap. The highways are generally good, with smooth pavement, light traffic, and lots of curves! And the Thai people are so friendly and helpful. That is a huge part of why I stay here and enjoy it so much.

So, yeah, even before mapping took over my life, I used to travel in the region. And, as I said, I used to write a blog, take photos and tweak them in Photoshop. I enjoy writing and still maintain the blog but just don't get around to posting in it as much as I used to. As they say, "so little time, so much to do."

Even while taking care of emails, I'm always having some sort of OSM-related conversation going in my head: how should I handle splitting that big multipolygon over near Omkoi? Or, what about finishing mapping the Susitna River in Alaska? When will you get back to mapping the natural features along the Sterling Highway between Homer and Soldotna? And then, for a really big project, there is always the Adirondack Forest Preserve in NYS. Phew! It's almost too much.

Again, thanks for the comments.

A Mapper in the Spotlight: Dave Swarthout (USA/Thailand) 11 days ago

Thanks for reading and taking the time to make comments. I felt honored to take part in Marc's series.

To Warin's comment, I am aware of the danger posed by riding a motorcycle with a camera around my neck but I just cannot figure another way to do my surveying. I sometimes stop to shoot the photos but mostly I do it while moving, another big no-no. I am exploring other ways to do that but so far haven't found one. I tried a Gopro camera with time-lapse turned on but it just isn't as good as those still photos.

Mapillary 10 months ago

I too would like to see a Mapillary plugin for JOSM. I occasionally use Google Streetview to double check my ground surveys but I'd like to be able to stop doing that, just as I have their other free (but not free) mapping toys.

Until that happens Mapillary will be just another interesting website to visit. OSM mapping has become an addiction and drives my every move these days. Having Mapillary photos accessible in OSM's most powerful editor seems a logical next step.


WikiProject Emergency Cleanup over 1 year ago

I'm not sure how much I'll be able to contribute to the discussion but I must say, I love the banner!

Thailand Mapping + London Mapping TONIGHT over 1 year ago

Hi Harry,

AlaskaDave here. I just happened to catch your post and enjoyed reading your observations about the state of OSM mapping in Chiang Mai. Actually, most of the folks on that OSM heat map live here or spend a lot of time here and love mapping. Thailand is, as you surmise, pretty well mapped in spots and in other places not so well. Chiang Mai is a popular place for expats. Johnny and Tom live here full time, Stephan visits often, and is vying to come here more or less permanently if he can arrange a telecommuting situation at his real job, and I share time between here and Alaska. There are a few Thais working Chiang Mai too but the foreigners, farangs, are much more active.

I'm about to leave Thailand for the hot months. I'll go back to Alaska, a huge state with very small population, and few OSM mappers. It's vast and mostly unmapped. Most of the main roads are present but not much geography. It's an immense project that I began working on last year and that I will work on for many months to come. Rivers, streams, islands, peaks, glaciers, trails — lots of work.

I don't spend much time in the south of Thailand where the beaches are but I'll take a look at those problem areas you mentioned. Did you happen to leave Notes on the map near the problems?

At the moment, I am almost ready to leave for the airport but I'll check the above links when I have more time.

Best, Dave

The Overpass Query Wizard almost 2 years ago

This is an awesome tool! Thank you.

I have used Overpass Turbo in the past and did find constructing queries to be both tedious and irksome. This tool makes it SO MUCH EASIER.


Mapping in Thailand about 2 years ago

Wow, your reservoir makes mine look tiny! Good job.

With OSM Inspector I looked at the geometry of the Kiew Ko Ma Reservoir and it all checked out with the exception of the two islands which had the error message "inner_in_inner". I changed their roles to outer and will wait to see how that checks out. At some point I will work up enough courage to try adding the two halves of the reservoir multipolygon together but using two distinct way segments for its outline in order to get around the 2,000 node limit. Thanks for bringing OSM Inspector to my attention. I have used it before but not enough to remember to employ it in diagnosing this problem.

Yes, I have read the documentation on multipolygons but it is not terribly helpful. The relation editor is another very opaque tool, difficult to use and not very user friendly. While there is much to like about JOSM, IMO it's help facility is sadly lacking. The Search tool is another I would take issue with but then, it is still vastly better than nothing at all.

You say "You can have multipolygons within multipolygons but you should try to avoid them if possible". Well, if that's the case, then how would you map a reservoir inside a pre-existing wood polygon, and then add islands inside the reservoir?

The other advice you gave from your first post:

"The outer perimeter should be split into sections of less than 1900 nodes and be part of a relation and defined as "outer". The islands should be mapped as islets and include other attributes such as "scrub" and be defined as "inner" within that same relation-number! Quite easy really."

is fine but I think you're forgetting that there was that pre-existing wood multipolygon into which the reservoir had to be inserted. How should I have handled that situation?

Thanks the the feedback and the helpful suggestions.


Mapping in Thailand about 2 years ago


Thanks for the info. I've already seen the f4 maps and they are indeed impressive

Please clarify how the reservoir can be defined with role outer when it is already enclosed within a larger wood multi-polygon, a polygon whose role is also "outer"

Someone else mentioned the idea of splitting the outline into two smaller pieces, and then making them part of a relation I have not done that before and would be afraid to try it. I can also assure you that I will not attempt to make such a node-heavy polygon again.