User:Carneyfex

My name is Petras Ražanskas, I have graduated as a BMath at Kaunas University of Technology and now I am going for MMath in the same institution. My main lines of research include artificial intelligence, visual recognition, control systems and robotics, but I deviate to other areas of mathematical expertise every once in a while. During my spare time I am a bassist and the primary music writer in an underground progressive rock band, which is recording their first album right now, which might be out by the end of the year. Also, I am an avid fan of geography. My first venture at on-line maps was Wikimapia project, where my primary areas of work were road and railway systems of Lithuania and, later, Latvia. Sadly, due to a major rift between administration and users, Wikimapia project seems to be an unwelcoming place to stay right now, and from all the alternatives OpenStreetMap seemed to be the best choice.

My goals for the nearest future

I have purchased a GPS device and now I am eagerly waiting for its arrival. It doesn't seem to be much, it costs only 85€, but it should be more than enough for my initial mapping needs. I will concentrate my effort on these areas at first:

• Petrašiūnai is very much the black hole of Kaunas, with only some streets marked, and even those are at very low resolution, looking jagged when one zooms in. I already started some smoothing to the best of my knowledge and what I have collected when I got to play with my friend's GPS, however, these data were very limited (I didn't even know, how to record a trace, so I just wrote down a bunch of coordinates and then used orthogonalization and circularization (where appropriate) tools provided in JOSM to make those points look good).
• I am not quite sure, but it seems that the only trace of public transportation in the map of Kaunas is a bunch of marked bus stops, and no routes have been marked as of yet. When I confirm this, I will take my time and go on all of those routes one by one with my GPS to
  1. get a better trace for the streets that are in lo-res;
  2. mark all of the bus stops, their names and other relevant information.
• I am also an avid fan of railways, so I would be more than happy to provide OpenStreetMap with better and smoother depictions of Lithuanian railways from wherever I go by train. I will make sure to take my GPS with me and add the data I collected. I will also collect the traces by going on foot where it's near where I live and when it is actually possible (I don't want to infringe any law by accessing restricted areas of industries or Lithuanian Railways).

What I have already done

Sadly, my imprint on the OpenStreetMap is as of yet very minute, but I plan on working on that, providing quality content from whatever data I collect with my GPS device. For now I have done the following:

• smoothing of marked streets in northeastern Petrašiūnai (using data from my friend's GPS)
• adding Petrašiūnai secondary school with its infrastructure (ditto)
• adding Šilas mall (ditto)
• marking Buriuotojų and Meškeriotojų streets deep in Pažaislis forest (ditto)
• adding bus stops and street crossings in eastern Petrašiūnai (ditto)

This list will be appropriately compressed as it grows to never exceed a sensible length of 20 or so points

How to mark a building my way

The easiest way to mark a building, of course, is to walk around it almost touching the wall, but it has the disadvantage of having half of GPS satellites blocked by the building itself most of the time, thus drastically reducing the precision of the device. What I do to avoid it if there is enough space around the building (that is subjective and depends on the actual height of the building) is I walk some steps away from the building, take a position where I am looking straight along one of the walls and then I walk 20 or more meters directly straight towards that wall. This gives me enough data to find the straight line that the wall of the building lies on. When all of these lines are found, the inner shape they make is the outline of the building. This shape can then be orthogonalized if appropriate and otherwise adjusted to fit the reality more.

Of course, if there are no problems with GPS reception, bothering with this geometric fiddling may be a lot more time consuming than just walking around and then correcting the data in JOSM. You can't beat this kind of linear interpolation technique when the building is not directly accessible though due to other buildings that are blocked with it or a fence in the way.

You are well advised to regard this advice with skepticism, because it comes from my very limited experience, but it is sure to be worked upon in the future.