OpenStreetMap

datalogg's Diary

Recent diary entries

NOT mapping Kibera

Posted by datalogg on 3 November 2009 in English.

Just read mapkibera.org, and spent a small hour mapping virgin Kibera from hi-res Yahoo! imagery, thinking it would be my way to help out.

Then decided not to upload it.

As much as I'd like to do my share, I had the feeling I'd kill the project if I plucked all the low-hanging fruit like that. I'd disregard all the thrill and the anticipation of the starry-eyed people waiting to get started on the ground. So that's one changeset I don't mind throwing away...

Mapping in Ukraine

Posted by datalogg on 6 October 2009 in English.

Am having a good time mapping in Ukraine. Managed to log large parts of the Kiev-Odessa and Odessa-Lviv railroads at a 1 sec intervals with excellent hdop, so when I get back to Holland I can correct some mistakes and even add a whole stretch of track. Met up with Igor Shubovych in Kiev and had some drinks, did some simple mapping, and talked about the map and what Cloudmade has in store (which is very impressive). Am logging restaurants and coffee bars as I hop from wifi to wifi, as well as waypointing certain amenities like public toilets. The funniest thing I've done is adding name:nl tags for some streets, so that KIev now has a street called the "Chresjatikstraat" and "Zolotaja Botsjka"-bar ;-)

Here's a tip I wanted to share about JOSM:

Oftentimes you want to make ways, areas, points, etc perfectly orthogonal or perpendicular. For instance, you want to grid-fit all streets in a "grid-type" city, or you want to align buildings perfectly to a street. Here's how to do it in JOSM:

Find a long, straight feature like a main street or a canal. This will be your baseline. Then draw a huge rectangle that easily covers the area of interest. Select the body of the rectangle and two endnodes of the baseline, and press Q. This will align the rectangle to the baseline and make it perpendicular. What you now have is a giant "ruler" that you can use to align streets.

Next step is to align streets along this "ruler". Position the ruler over a street, select the two endpoints of the leg of the ruler and all the points of the street, and press L. All the street's nodes will be aligned to the ruler! Lather, rinse, repeat.

Once you have perpendicular streets, the nice thing is that you can shift streets in the X and Y directions independently of each other. If you want to move a street a bit to the right, say, then your new alignment action will not affect streets going from top to bottom.

To align buildings (or other areas) perfectly to a street and make them perpendicular, select two points on the street and the body of the building/area, and press Q.