5 ms·

I don't understand what this is and where the "Portable Offline Open Street Map" part is described. There are already tons of applications for offline OSM usag

by anc84 11y ago

I don't understand what this is and where the "Portable Offline Open Street Map" part is described. There are already tons of applications for offline OSM usage. There are even (sadly) many different vector formats and files available for download. It would be nice to focus improvement of those instead of developing yet another competing standard. I want to be able to use multiple apps with the same data, not having to provide each app with its own format (looking at you, OSMAnd, Oruxmaps, maps.me...).

chippy 11y ago
I cannot see where the "of the world" bit comes into it, but essentially I think it's offline editing.
detaro 11y ago
I'd say it is to have a server with an offline fork, which a) provides you access to OSM without internet (which is the "boring" part) and b) allows you to make changes when you get new data. When you return to somewhere with better internet, you then can sync the changes to upstream OSM. And all that prepackaged so it is easy to prepare and deploy to a laptop, a small portable server, ...
- beagle3 11y ago
  a) is "boring", but last I looked was still far from a simple installation (tar.gz, apt-get, docker or otherwise). On mobile now, so I can't test but if this is a simple way to start a local read only server, it is already a significant improvement.
  - rmc 11y ago
    There isn't a load of benefit to having a read only OSM API database. If you want to load the data into an OSM editor like JOSM, you can open an OSM XML file. If you want to render maps from OSM data, you have to load it into postgresql with osm2pgsql which works with OSM pbf or xml files. A local API db is rarely useful.
  - voltagex_ 11y ago
    Simpler - https://github.com/AmericanRedCross/posm-build https://github.com/AmericanRedCross/posm-build seems to be based on Ubuntu 14.04 with some extra packages. There's also a Kickstart script.
    - beagle3 11y ago
      Thanks -- that's from the original article, whose contribution describing an easy way to set up a local OSM server is what I was applauding.
ZenoArrow 11y ago
Don't they all work with ESRI Shapefiles?
- maxerickson 11y ago
  Can you explain in more detail what you are asking? In general, the Android/ios apps have their own file formats and then have a PC tool for generating those maps. It's relatively trivial to feed a shapefile into those generators (install GDAL/OGR and convert to a format the tool accepts), but there is not really a standard schema in use in shapefiles so it is also necessary to map the attributes in the shapefile over to something the app will understand (or to provide a custom style to the app that is based on the shapefile schema).
  - ZenoArrow 11y ago
    My understanding (and I only have a passing knowledge about GIS data formats) is that the ESRI shapefile is the closest to a vector data format that most/all mapping software supports. I wasn't aware that shapefiles aren't standardised. From the Wikipedia page (https://en.wikipedia.org/wiki/Shapefile https://en.wikipedia.org/wiki/Shapefile ), it looks like this is the official spec: http://www.esri.com/library/whitepapers/pdfs/shapefile.pdf http://www.esri.com/library/whitepapers/pdfs/shapefile.pdf Do you have any examples of implementations that differ from this spec?
    - maxerickson 11y ago
      What I'm talking about would probably fall under "Organization of the dBASE file". Except it's left to the user. Is a street name given under "FULLNAME" or is is only provided in the parts "PREFIX" "NAME" "SUFFIX". How are various things categorized. Is there a "FUNCTION" column, or a "USE" column. To be useful, software needs instructions how to interpret that information. That's what I meant by a style. As an example, it might be necessary to map a value of "A41" given in the "CFCC" column to an osm property like "highway=residential". This is a real example from the US imports of TIGER data. A41 means "Local, neighborhood, and rural road, city street, unseparated.", so that mapping is a little bit unfortunate, as in OSM, highway=residential is unlikely for a rural road. As far as shapefiles being a vector data format that mapping software supports, the device apps aren't really mapping software in that sense, they are too specialized (I think in large part because users of that software expect premade feature styling).

by anc84 11y ago

chippy 11y ago

I cannot see where the "of the world" bit comes into it, but essentially I think it's offline editing.

detaro 11y ago

I'd say it is to have a server with an offline fork, which a) provides you access to OSM without internet (which is the "boring" part) and b) allows you to make changes when you get new data. When you return to somewhere with better internet, you then can sync the changes to upstream OSM. And all that prepackaged so it is easy to prepare and deploy to a laptop, a small portable server, ...

beagle3 11y ago
a) is "boring", but last I looked was still far from a simple installation (tar.gz, apt-get, docker or otherwise). On mobile now, so I can't test but if this is a simple way to start a local read only server, it is already a significant improvement.
- rmc 11y ago
  There isn't a load of benefit to having a read only OSM API database. If you want to load the data into an OSM editor like JOSM, you can open an OSM XML file. If you want to render maps from OSM data, you have to load it into postgresql with osm2pgsql which works with OSM pbf or xml files. A local API db is rarely useful.
- voltagex_ 11y ago
  Simpler - https://github.com/AmericanRedCross/posm-build https://github.com/AmericanRedCross/posm-build seems to be based on Ubuntu 14.04 with some extra packages. There's also a Kickstart script.
  - beagle3 11y ago
    Thanks -- that's from the original article, whose contribution describing an easy way to set up a local OSM server is what I was applauding.

ZenoArrow 11y ago

Don't they all work with ESRI Shapefiles?

maxerickson 11y ago
Can you explain in more detail what you are asking? In general, the Android/ios apps have their own file formats and then have a PC tool for generating those maps. It's relatively trivial to feed a shapefile into those generators (install GDAL/OGR and convert to a format the tool accepts), but there is not really a standard schema in use in shapefiles so it is also necessary to map the attributes in the shapefile over to something the app will understand (or to provide a custom style to the app that is based on the shapefile schema).
- ZenoArrow 11y ago
  My understanding (and I only have a passing knowledge about GIS data formats) is that the ESRI shapefile is the closest to a vector data format that most/all mapping software supports. I wasn't aware that shapefiles aren't standardised. From the Wikipedia page (https://en.wikipedia.org/wiki/Shapefile https://en.wikipedia.org/wiki/Shapefile ), it looks like this is the official spec: http://www.esri.com/library/whitepapers/pdfs/shapefile.pdf http://www.esri.com/library/whitepapers/pdfs/shapefile.pdf Do you have any examples of implementations that differ from this spec?
  - maxerickson 11y ago
    What I'm talking about would probably fall under "Organization of the dBASE file". Except it's left to the user. Is a street name given under "FULLNAME" or is is only provided in the parts "PREFIX" "NAME" "SUFFIX". How are various things categorized. Is there a "FUNCTION" column, or a "USE" column. To be useful, software needs instructions how to interpret that information. That's what I meant by a style. As an example, it might be necessary to map a value of "A41" given in the "CFCC" column to an osm property like "highway=residential". This is a real example from the US imports of TIGER data. A41 means "Local, neighborhood, and rural road, city street, unseparated.", so that mapping is a little bit unfortunate, as in OSM, highway=residential is unlikely for a rural road. As far as shapefiles being a vector data format that mapping software supports, the device apps aren't really mapping software in that sense, they are too specialized (I think in large part because users of that software expect premade feature styling).