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Getting Started Developing With OpenStreetMap Data
Nerval's Lobster writes In 2004, Steve Coast set up OpenStreetMap (OSM) in the U.K. It subsequently spread worldwide, powered by a combination of donations and volunteers willing to do ground surveys with tools such as handheld GPS units, notebooks, and digital cameras. JavaScript libraries and plugins for WordPress, Django and other content-management systems allow users to display their own maps. But how do you actually develop for the platform? Osmcode.org is a good place to start, home to the Osmium library (libosmium). Fetch and build Libosmium; on Linux/Unix systems there are a fair number of dependencies that you'll need as well; these are listed within the links. If you prefer JavaScript or Python, there are bindings for those. As an alternative for Java developers, there's Osmosis, which is a command-line application for processing OSM data.
And actually hacking. I think I may give this a try.
I would like to know how this story relates to Systemd
The 70's called looking for it...
Yeah, I often misplace things 40 years in the future, or more sometimes! You know how it is, it's a busy day, my mind is somewhere else, and poof! I can't find my command line application. So I just look up the number for every year in the future and start calling. I've called a lot over the years. If someone told you the 80s called and want something back, I'm sorry for bothering you.
Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
this site also used to have technical stories. like this one. so its actually a welcome change from "what would benet..." series.
Rich
Please make him contribute again.
For a project I'm working on, I started to play around with the OpenStreetMap data as a source for locations (from a guy who's never used GIS info systems), so I think I'd be a good insight into getting started with using this great resource.
Notes:
- I develop in Java mostly, but I have a generally well rounded skill set.
Firstly, I had to make the jump to Postgress and PostGIS, which are annoying to setup if you're not familiar with them. I had a MySQL instance running, but for the life of me, I couldn't get osmosis to import before getting the setup just right, which unfortunately wasnt' as simple and stright forward as I'd have liked to see in any docs. So after finally banging PostGIS over the head enough to accept the import, I was hit with a huge knowledge gap on how to actually access spatial and hstore based data. Admittedly, once you get the handle of them, the SQL access the data is quite expressive and powerful.
For DB imports, I used Osmosis for data import. I couldn't find any stand-alone Java based libaries for actually using the DB data which would help a lot (maybe I'll end up writing an open source one if it doesn't already exist). So, I basically dropped down to writing PostGIS based SQL queries, which is really quite expressive and well structured when the data is good (depends on the world region, mostly good for North America from what I found so far).
Secondly, there was the OpenStreetMap data itself. As someone who primarily wants to work on geographic barriers and political boundaries, there's a big disconnect between the polygons of the system and the political ones. Generally, there's always a node (think of a pin on a map) to represent a proper place name (New york city for instance) and a polygon that encompass what New York's political boundaries are, but quite often there won't be explicit ties between the two, so you're left with bridging the two yourself constructing queries for where nodes are within city / state / country / etc.. Anyways, thats as far as I've gotten so far, so good luck!
Some links that helped me:
http://www.postgresql.org/docs...
http://postgis.net/docs/manual...
http://wiki.openstreetmap.org/... (Make sure to read carefully, becase its rather unforgiving and terse about bad environment setups)
Bye!
Their bus stops are all out of date for where I live
Hear hear! Bring back Bennett! It was the only thing keeping this website interesting.
As a developer of GIS systems you can earn very good money indeed. Why would anyone want to do it for free?
I was doing some development with OSM and was using my own formulae to convert from latitude/longitude to OSM tile coordinates. I spent days getting the wrong results until I realised the problem was pi. i had been using pi=3.1415926535. It turns out that that is not GOOD enough to zoom into house level. I added 5 extra 5 or so digits of PI and then all my tiles were correct to the house level. I was awed that for a simple, practical task i needed 15 digits of pi!
I'm playing around with viewing OSM data. I like the MarbleWidget. (And despite the KDE link, it only needs Qt, not the whole KDE Stack.)
Red to red, black to black. Switch it on, but stand well back.
No need to converge on some phantom OSM paradigm. It is just data, you can use anything you want for the .dev end of it. OSM has lots of interesting tolls, most of which could use a lot more mature approach of an enterprise, mostly on the data quality verification and maintenance end, as wholesale breakage is not prevented just as in Wikipedia.
I'm all for using open source software and information but it has to be at least 90% as good as the commercial alternatives especially if those commercial alternatives are reasonably priced. I'm going on a trip to Las Vegas, a city with extremely complex infrastructure including multiple monorail systems, a public bus system, complex streets, taxi and bus specific lanes, and a high density of shops and restaurants residing on multiple levels in extremely large buildings. I figured it would be the perfect opportunity for OSM to show off the best it has to offer.
Google appears so overwhelmingly better at handling all of those complex mapping scenarios to the point where OSM can't be seriously considered for people trying to use it to navigate that city. Most business data is out of date, public transit stops aren't as detailed, and it doesn't have the internal structures of buildings that take up multiple city blocks.
Interestingly enough my own city's OSM data is top notch, easily surpassing Google's data. Clearly there seems to be wide range of map data in the database, but I would think large cities that people travel to often seems like the place you really want high quality data and visualization if you want non-ideological users to switch. Had I not looked at my own community I would have written off OSM as a totally underdeveloped open source project with no chance of competing, and it seems like that's the exact opposite of the potential it has, but clearly there needs to be more outreach in some larger cities.
I think i will try this,maybe it will be helpfull to my site http://www.bagswalletsforsale....
The current one is awful. Most features are not clickable and don't have tooltips or any other discoverable way to access metadata. Icons are not explained. Layers are not customizable at all. I know it's all open source, but then why is nothing happening on the front end?
"if something is free, you are the product" ... is a pretty good rule of thumb. It's only sensible to have a healthy level of cynicism about websites and companies operating them, especially websites which are asking to volunteer your time towards contributing to a dataset. There are countless websites operated by profit-making companies, which do this, and then don't behave well. The most basic cardinal sin here is not giving the data back under an open license. This applies to geo datasets with things like Google Map Maker and Waze. "you are the product" is very much true in this case. So yes, be cynical. Before spending time on these things, look into it carefully, and don't contribute to projects which are not treating contributors fairly.
But if you look into OpenStreetMap carefully, you'll find a similar set-up to Wikipedia. You'll find everything is released with an open license. You'll find a not-for-profit organisation with oversight over servers and funding. You'll find a large open community of volunteers who are just trying to make the world a better place by building something great.
Be cynical. Be suspicious. Contribute your time wisely. Contribute to OpenStreetMap.