gpx - Extracts waypoints, tracks and routes from GPX files
package require Tcl 8.5
package require gpx ?0.9?
::gpx::Create gpxFilename ?rawXML?
::gpx::Cleanup token
::gpx::GetGPXMetadata token
::gpx::GetWaypointCount token
::gpx::GetAllWaypoints token
::gpx::GetTrackCount token
::gpx::GetTrackMetadata token whichTrack
::gpx::GetTrackPoints token whichTrack
::gpx::GetRouteCount token
::gpx::GetRouteMetadata token whichRoute
::gpx::GetRoutePoints token whichRoute
This module parses and extracts waypoints, tracks, routes and
metadata from a GPX (GPS eXchange) file. Both GPX version 1.0 and 1.1 are
supported.
- ::gpx::Create gpxFilename ?rawXML?
- The ::gpx::Create is the first command called to process GPX data.
It takes the GPX data from either the rawXML parameter if present
or from the contents of gpxFilename, and parses it using
tdom. It returns a token value that is used by all the other
commands.
- ::gpx::Cleanup token
- This procedure cleans up resources associated with token. It is
strongly recommended that you call this function after you are done
with a given GPX file. Not doing so will result in memory not being freed,
and if your app calls ::gpx::Create enough times, the memory leak
could cause a performance hit...or worse.
- ::gpx::GetGPXMetadata token
- This procedure returns a dictionary of the metadata associated with the
GPX data identified by token. The format of the metadata dictionary
is described below, but keys version and creator will always
be present.
- ::gpx::GetWaypointCount token
- This procedure returns the number of waypoints defined in the GPX data
identified by token.
- ::gpx::GetAllWaypoints token
- This procedure returns the a list of waypoints defined in the GPX data
identified by token. The format of each waypoint item is described
below.
- ::gpx::GetTrackCount token
- This procedure returns the number of tracks defined in the GPX data
identified by token.
- ::gpx::GetTrackMetadata token whichTrack
- This procedure returns a dictionary of the metadata associated track
number whichTrack (1 based) in the GPX data identified by
token. The format of the metadata dictionary is described
below.
- ::gpx::GetTrackPoints token whichTrack
- The procedure returns a list of track points comprising track number
whichTrack (1 based) in the GPX data identified by token.
The format of the metadata dictionary is described below.
- ::gpx::GetRouteCount token
- This procedure returns the number of routes defined in the GPX data
identified by token.
- ::gpx::GetRouteMetadata token whichRoute
- This procedure returns a dictionary of the metadata associated route
number whichRoute (1 based) in the GPX data identified by
token. The format of the metadata dictionary is described
below.
- ::gpx::GetRoutePoints token whichRoute
- The procedure returns a list of route points comprising route number
whichRoute (1 based) in the GPX data identified by token.
The format of the metadata dictionary is described below.
- metadata
dictionary
- The metadata associated with either the GPX document, a track, a route, a
waypoint, a track point or route point is returned in a dictionary. The
keys of that dictionary will be whatever optional GPX elements are
present. The value for each key depends on the GPX schema for that
element. For example, the value for a version key will be a string, while
for a link key will be a sub-dictionary with keys href and
optionally text and type.
- point item
- Each item in a track or route list of points consists of a list of three
elements: latitude, longitude and metadata
dictionary. Latitude and longitude are decimal numbers.
The metadata dictionary format is described above. For points in a
track, typically there will always be ele (elevation) and time metadata
keys.
% set token [::gpx::Create myGpxFile.gpx]
% set version [dict get [::gpx::GetGPXMetadata $token] version]
% set trackCnt [::gpx::GetTrackCount $token]
% set firstPoint [lindex [::gpx::GetTrackPoints $token 1] 0]
% lassign $firstPoint lat lon ptMetadata
% puts "first point in the first track is at $lat, $lon"
% if {[dict exists $ptMetadata ele]} {
puts "at elevation [dict get $ptMetadata ele] meters"
}
% ::gpx::Cleanup $token
- [1]
- GPX: the GPS Exchange Format
(http://www.topografix.com/gpx.asp)
- [2]
- GPX 1.1 Schema Documentation
(http://www.topografix.com/GPX/1/1/)
- [3]
- GPX 1.0 Developer's Manual
(http://www.topografix.com/gpx_manual.asp)
This document, and the package it describes, will undoubtedly
contain bugs and other problems. Please report such in the category
gpx of the Tcllib Trackers
[http://core.tcl.tk/tcllib/reportlist]. Please also report any ideas for
enhancements you may have for either package and/or documentation.
When proposing code changes, please provide unified diffs,
i.e the output of diff -u.
Note further that attachments are strongly preferred over
inlined patches. Attachments can be made by going to the Edit form of
the ticket immediately after its creation, and then using the left-most
button in the secondary navigation bar.
Copyright (c) 2010, Keith Vetter <kvetter@gmail.com>