Matti Nykyri <matti.nyk...@iki.fi> [14-09-30 19:44]: > > On Sep 30, 2014, at 17:12, Alec Ten Harmsel <a...@alectenharmsel.com> wrote: > > > > > > >> On 09/30/2014 10:05 AM, meino.cra...@gmx.de wrote: > >> Suppose the GPS would already be attached > >> to the board and works... > >> > >> Is there any free available software and data for > >> strict offline useage (which does NOT calls > >> to home), which is able to map GPS data to a street/land > >> map? > >> I need both: The maps themselves and the logic to read > >> GPS coordinates and map movements and ways to those maps. > >> > >> Is something like that available for free or should > >> I directly ask the NSA/CIA/FBI/...? > >> > >> Thank you very much in advance for any help! > >> Best regards, > >> mcc > > The only project I know of that has openly available map data is > > OpenStreetMap (openstreetmap.org). I know they have an API, and they > > probably (not sure) have maps available for download. > > > > afaik the only way to combine various map data out of the box is to use > > a GIS package like QGIS. You can write software to do this using the > > proj4 library for an embedded box, not sure if anything for your > > specific use case already exists and is open source. > > > > Alec > > Sorry iphone send mail even if you don't wanna :/ > > What you are considering doing is quite a challenge. What kind of coordinates > does your gps module give you? The gps system works with cartesian x y z > coordinates. Then these are usually displayed to the user in WGS-84. This is > a quite hard mathematical problem (differential elliptical problem). Usually > is done by your gps receiver and is approximated. GIS libraries have these > functions built inside. Distances are easier and faster to calculate in > cartesian coordinates. You need to calculate distance because coordinates > from gps will never coincide with any address. > > Open street maps provides a very good start, but addresses have great > differences in different countries. For example google misses addresses quite > much depending on where you are searching. Getting the address right requires > good locality from the program. Addresses and roads are vector maps. The > fastest way to get address is to have the vector map of the world and then > calculate distance to the closest address. The database will be huge :) > > Maps are usually raster pictures which have some projection. When you display > them you can use 3d or 2d visual. In 3d (like google earth) you draw a sphere > (or oblate spheroid) and draw textures on top of is to the right coordinates. > In 3d everything needs to be converted to cartesian coordinates. Or in 2d you > decide a projection and then convert the projection of your maps to this > projection. After that it is just easy drawing. GIS libraries contain all the > needed tools for these operations. There are a few of them with open source > license. > > I have been doing some work with opengl 3d drawing maps. Good luck your > project is quite big but it is sure very much fun :) > > -- > -Matti > > >
YEAH! Matti is back! I saw your previous mail and thought: Oh boy...Clint Eastwood is very talkative compared to /him/. ;;;))) I am not /that/ serious this evening...sorry... With all the help from this forum this evening I got by far more working results as I have thought... But back to your mail: The GPS module I plan to use is this one (by Adafruit, Lady Ada): https://learn.adafruit.com/adafruit-ultimate-gps/overview >From there (see link list on the left) you can also download the manuals (pdf). I will not use this thing as a driving assistant or "navi" (is this common speaking outside germany also...or is it one of those pseudo english german words like "handy" for "cell phone"...dont laugh! This time /I am/ serious! :) ) Its more like a GPS data logger. I plan to copy the gathered data on my PC later and I will try to "draw" them onto a map. May be the results proof later, that I am able to walk through walls and hovering over the face of the waters...;) May be the UV-mappinga abillity of this 3D renderig program will help -- I am using it for other purposes since 2006. www.blender.org Will see how far it will go. First step in progress will be acchived, when I can read any data from the GPS module and they are not that changing if I dont move and they will change when I move. The module is ordered and will arrive -- I hope -- next week. Best regards, mcc
