My 5 cent of Olivers suggestion: A possible use and implementation case could be:
Use case I: - Read the track into QMS - Create 1 to n waypoints near the track for possible new track start points - The waypoints will be recognized internally as "assigned track waypoints" within a threshold of 50m - Maybe rename the waypoints by proper names Implementation: - Development of a new track filter "Reassign start point", maybe in the section "Miscellaneous" - GUI could be very simple: One Combobox with the list of the names of the assigned track waypoints and the "Compute" pushbutton - The track vector of the given points has internally be reordered from "n" to "end point" from "end point" "to start point" from "start point" to "n" Use Case II: - Select an assigned track waypoint from Combobox list and push the button of "Compute" - Then track points will be reordered beginning with the selected track waypoint Still to be consider: - Implementation will be consider "all" kind of tracks, a non circle track will be then linked from end to start point, may be a long straight line from end to start point will be the shown - Tracks with internal multiple segments will be transformed to one internal segment - How to handle history (I am not experienced in that)? - Timestamps of the track points has maybe reassign by a new starting date and time (has to reflect a bit more in detail) Hope it helps. Karl ... Am Dienstag, den 13.03.2018, 19:08 +0100 schrieb Oliver Eichler: > Ah, ok I recall the stuff. > > > I do not know of a library to read GPX files written in C or C++. In > the first > place you need an XML parser and writer. There are libraries for that > task. Qt > has one, too. That's what I use in QMS. > > Of course you can extract the code from QMS. But the GPX and track > classes and > their sub-classes are quite some beasts. After all tracks are > incredible > complex GIS items. > > So you might end up like Karl, writing your own track filter in QMS. > By that > you can focus on the task without dealing too much with GPX, drawing > stuff > etc.. > > > Oliver > > > > > > Am Dienstag, 13. März 2018, 14:07:43 CET schrieben Sie: > > > > -------- Weitergeleitete Nachricht -------- > > Betreff: Fwd: Re: [Qlandkartegt-users] Shift the Startpoint > > from a > > track to another point; Programming an own tool > > Datum: Tue, 13 Mar 2018 14:03:35 +0100 > > Von: APM <[email protected]> > > An: Qmapshack mailing list <[email protected] > > forge.net> > > > > > > > > Note: I got a SMTP error for my first mail, second try. > > > > Hi Oliver, > > > > > > yes of course! > > > > We mainly use circle hiking paths, the tracks are given. The track > > starts and end at the same point. > > > > But from time to time we start and finish at another point on the > > circle. > > > > Problem: If I use my Garmin GPS with this track, the "journey- > > computer" > > (in German menue 'Reisecomputer') shows me the remaining distance > > and > > time to the end of the track, which is not the endpoint we really > > have > > and the remaining distance and time are 'wrong'. > > > > My idea is to manipulate the track in this way, that I define a new > > startpoint and the c++ programm change the trackpoints in > > accordance to > > the new startpoint. > > > > So far as I know, the Garmin GPS can't do a shift of a startpoint > > from a > > track. > > > > > > Kind regards > > > > > > Axel > > > > Am 13.03.2018 um 12:57 schrieb Oliver Eichler: > > > > > > Can you explain again what you want to do? It sounds like moving > > > trackpoints without changing the timestamp or other properties. > > > > > > Oliver > > > > > > > > > > > Gesendet: Dienstag, 13. März 2018 um 10:09 Uhr > > > > Von: APM <[email protected]> > > > > An: "Qmapshack mailing list" <[email protected] > > > > rge.net> > > > > Betreff: [Qlandkartegt-users] Shift the Startpoint from a track > > > > to > > > > another point; Programming an own tool > > > > > > > > Dear all, > > > > > > > > for a couple of month I asked in this list how to shift a > > > > startpoint > > > > from a given track without to cut and assemble the track. > > > > > > > > It's a pity, but I have no solution until now or do not > > > > understand what > > > > to do in this case. > > > > > > > > My idea is to progamm a tool in C++ of my own, but I'm > > > > inexperienced. > > > > > > > > My question is, if there's a class in the libary I can use or > > > > maybe a > > > > similar tool is already present? > > > > > > > > > > > > Thank you very much! > > > > > > > > > > > > Kind regards > > > > > > > > > > > > Axel > > > > > > > > > > > > > > > > > > > > ------------------------------------------------------------- > > > > ------------ > > > > ----- Check out the vibrant tech community on one of the > > > > world's most > > > > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > > > > _______________________________________________ > > > > Qlandkartegt-users mailing list > > > > [email protected] > > > > https://lists.sourceforge.net/lists/listinfo/qlandkartegt-users > > > --------------------------------------------------------------- > > > ----------- > > > ---- Check out the vibrant tech community on one of the world's > > > most > > > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > > > _______________________________________________ > > > Qlandkartegt-users mailing list > > > [email protected] > > > https://lists.sourceforge.net/lists/listinfo/qlandkartegt-users > > > ------------------------------------------------------------------- > ----------- > Check out the vibrant tech community on one of the world's most > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > _______________________________________________ > Qlandkartegt-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/qlandkartegt-users ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Qlandkartegt-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/qlandkartegt-users
