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    Navigation software Moderator kunix's Avatar
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    Can we just imagine some generic coordinate conversion formula and calculate its constants by comparing encoded and original coordinates for a few points?
    In case of a plane it's something like (Xenc,Yenc) = (X*A11+Y*A12,X*A21+Y*A22) + (B1,B2).

    Also what is the program that uses those .db files? I can't find "trails", "trail_segs" strings in the MapSource.exe.
    Got it, it's basecamp.
    Last edited by kunix; 22nd August 2012 at 05:44 PM.

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    Data in SQL (.db) filesData in SQL (.db) files GPSFranz's Avatar
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    Quote Originally Posted by kunix View Post
    Can we just imagine some generic coordinate conversion formula and calculate its constants by comparing encoded and original coordinates for a few points?
    In case of a plane it's something like (Xenc,Yenc) = (X*A11+Y*A12,X*A21+Y*A22) + (B1,B2).

    Also what is the program that uses those .db files? I can't find "trails", "trail_segs" strings in the MapSource.exe.
    Got it, it's basecamp.
    The .db files are SQLite database files containing tables of trails and trail segments (see previous posts).
    These are used by BaseCamp and some of the newer GPS units to find and display 'Named Trails' for a given map and area.
    This feature was added recently, and therefore (as far as I know) Mapsource does not support it.

    I think comparing encoded and original coordinates for a few points is a good idea.
    The tables in 010-D1215-00.db give plenty of points (I guess more than 1000) and their encoded coordinates.
    Unfortunately, the tables provide only numerical node IDs (177569, 177607, 177367, etc.) for the points (not names or anything giving a hint at their location).
    How can we find out where a given point identified only by its node ID is located?
    Maybe this will be of help:
    The table 'trails' lists several trails (with different IDs and names) which, I guess, are separate trails that are part of the whole trail commonly called 'GR G1'. Let's call them subtrails.
    This could help to narrow down the geographic area for a given subset of 'nodes'.
    The subtrails listed in the table 'trails' are (I provide trail ID and name):

    50002 GR G1
    50003 GR M1
    50004 GR MT1
    50005 GR R1
    50006 GR R2
    50007 GR R3
    50008 Le sentier Mangrove de Dapani
    50009 Le sentier Padza de Bouéni
    50010 Le sentier Vanille de Chiconi
    50011 Le sentier Ylang de Dzoumonyé

    It would be nice have a person familiar with the area here on Noeman (but I don't count on it).
    So I have started to use Google to search for the subtrail names (to find hints at their original coordinates), with limited success.
    Ideally, we would want to have .gpx files with tracks, routes and/or waypoints for these subtrails.
    Any ideas?

    PS: There is a 'subtrail' called GR G1. This is not the whole trail commonly called GR G1 (at least as far as I understand it).
    Last edited by GPSFranz; 22nd August 2012 at 06:57 PM. Reason: clarification
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