Jyrki Kuoppala - 2012-08-21

Not sure if a better place would be this or email, but I'll try here, if someone thinks it's better by email, let's move there.

I expect to be soon working more on using the Finnish National Land Survey's free / open datasets on GpsMid. Basically, the official governmental Land Survey has opened most of the data sets used to making topographic maps, and also names of national roads, data to generate a comprehensive set of house numbers and so on, can't even remember everything. See http://www.maanmittauslaitos.fi/en/opendata for details, not sure how much is in English.

I have added the required license info to GpsMid's map display, splash and COPYING-MAPS file. I've already built one sample GpsMid bundle for a small area, containing only roads though - seems to work for navigation. Not distributed anywhere though at the moment.

The question - does anyone have any objections to hosting Finnish free GpsMid maps built from NLS database on the SF site for GpsMid? For now, the map bundles would contain _only_ NLS data, no OSM data at all, due to licensing.

Another place which might benefit from alternative map data is Australia. If I understand correctly, substantial parts of the Australian OSM data have been removed due to licensing being incompatible with ODbL (having been imported from local land survey or the like). Not sure of the details, but might be a GpsMid map built for Australia from the old OSM data and/or the land survey data could be useful.

Can't yet estimate the size of what the bundles will be in the long run, but there's a file size limit in the SF web hosting. I think we ran into this when bundles were at SF; maybe somewhere between 50-200 Mb ? https://sourceforge.net/apps/trac/sourceforge/wiki/Project%20web%20and%20developer%20web%20platform mentions the limit but doesn't specify what it is.

The road data is 434 MB (finland.osm.bz2 is ca. 200 Mb), while the main database (with lakes, topographic info, etc.) is ca. 9,8 Gb. That data is distributed elsewhere, just talking about map bundles for SF distribution. The resulting map bundle with both area formats from OSM data is ca. 300 MB, which maybe can give some estimate of what the NLS data will ad up to. This is probably too much for the SF file size limit. At first, I expect to distribute only partial area maps, and probably as otherwise the file size would grow too much, for maps with many data types the areas would be less than country-wide even later.

Later, if support for multiple maps will be added to GpsMid and if the ODbL change goes as planned, might have bundles containing both OSM & NLS data, but that's a different discussion.