[OSM-dev] c-programmer at your command
artem.mapnik at googlemail.com
Fri Feb 8 12:33:54 GMT 2008
On 8 Feb 2008, at 11:54, SteveC wrote:
> I agree OSM in OGR is good but doesn't osm2pgsql -> OGR -> anything
> also work?
Of course, it does.
> On 7 Feb 2008, at 23:50, Milo van der Linden wrote:
>> Hello Hendri (and list)
>> There is a piece of GIS-translation Open Source software that is
>> currently head of the horde.
>> It mainly consists of two pieces:
>> - OGR; for translating from an to all kind of GIS formats (including
>> shape files and postGIS)<http://www.gdal.org/ogr/>
>> - GDAL; for raster files warping, georeferencing and
>> OGR/GDAL is solid and extremely active. Their community is even
>> then the OSM community consisting mostly of GIS professionals.
>> I have been posting messages to the GDAL/OGR development team to get
>> as a recognized datasource integrated in their software.
>> Mainly because adding OSM data format to OGR would open up the vault
>> ALL available GIS formats to get your OSM data into!
>> I know there is an OSM2PostGIS and attempts have been made to create
>> stable OSM2SHP conversion software, but adding it to OGR would realy
>> speed up things.
>> So, if you are well at home in C and C++, maybe you would like to
>> consider joining the OGR/GDAL team to get OSM as a solid and reliable
>> data adapter?
>> My knowledge on OGR is excelent as a user, not as a programmer.
>> But my
>> bet would be on OGR when I would have the skills to join them.
>> Hendrik Siedelmann schreef:
>>> This Project is great, and so I thought I'd like to help. As I do
>>> own a GPS-device the only possibility is to lend my programming
>>> in the c language.
>>> For now I already have some (ugly) code that parses an osm file and
>>> loads the ways into an r-tree, to allow fast lookup of areas. I also
>>> added some first svg export.
>>> But befor I begin developing something that someone else has already
>>> done, what Is needed the most:
>>> - fast Database as a backend for osm-based applications
>> postGIS, definitly!
>>> - unified osm to svg converter
>> Why only stick with svg when OGR opens up a whole lot of data formats
>> for you?<http://www.gdal.org/ogr/ogr_formats.html>
>>> - ... something else I could do?
>> I think that routing is the way to enhance OSM for the near future.
>> There is an implementation of Dijkstra algorithm for postGIS
>> But it would be good to set up a good algorithm that is more general
>> based on binary files rather then database tables, thus optimizing
>> People are already working on using OSM with qGIS for routing
>> <http://blog.qgis.org/?q=node/73> check it out!
>>> Also I have (of Course ;) ) some notes to make his Project even
>>> Why do nodes and ways have to be split? This makes working with osm
>>> data pretty complicated, as it requieres a database to work with,
>>> just to get the data of one way requires many node lookups, which is
>>> slow, especially if osm data would be use on handheld devices.
>>> Couldn't nodes simply be identified by their coordinates? This would
>>> also require less memory.
>> This is one of the main issues in my opinion too. Therefor good
>> translation software needs to be made to get OSM data into a routing
>> optimized binary file structure with r-tree functionality?
>>> Bezier curves. They are currently added via post-processing, which
>>> means suboptimal results, the mapper has little influence on the
>>> appearence and there are basically no memory savings. Instead of
>>> adding a rounding tag which does not solve most of these issues,
>>> about deriving the bezier curves from original data?
>>> Gps-Tracks a series of points, and propably also most of the other
>>> sources of map data? (I don't know). So if the mapper simply
>>> that the points between two points in the track form a way, then we
>>> could derive static sets of (bezier-) map data. And route
>>> and so on can be done on the original simple data.
>> Beziers are a major problem in ALL gis file formats. So if you
>> come up
>> with a solution there is a great future for you.
>>> Well thats it for now.
>>> Here is the database I coded for now (better dont't look at it ;) ):
>>> When started it reads from a file "map_p" in the working dir, which
>>> could be a pipe from a decompressor. The program writes data to
>>> "/tmp/osm/" so be sure to create this directory!
>>> After the import is finished, the Program will ask for
>>> latitude/longitude pairs and then dump a svg file named "place.svg"
>>> the working dir.
>>> The program is slow at the moment, so better test with a small
>>> dataset. I chose ther Germany extract of the planet dump.
>>> Here is such an svg dum:
>> Good luck and welcome to the team!
>>> dev mailing list
>>> dev at openstreetmap.org
>> dev mailing list
>> dev at openstreetmap.org
> have fun,
> SteveC | steve at asklater.com | http://www.asklater.com/steve/
> dev mailing list
> dev at openstreetmap.org
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