48 lines
2.1 KiB
Plaintext
48 lines
2.1 KiB
Plaintext
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= GPX Gem
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Copyright (C) 2006 Doug Fales
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Doug Fales mailto:doug@falesafeconsulting.com
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== What It Does
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This library reads GPX files and provides an API for reading and manipulating
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the data as objects. For more info on the GPX format, see
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http://www.topografix.com/gpx.asp.
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In addition to parsing GPX files, this library is capable of converting
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Magellan NMEA files to GPX, and writing new GPX files. It can crop and delete
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rectangular areas within a file, and it also calculates some meta-data about
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the tracks and points in a file (such as distance, duration, average speed,
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etc).
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== Examples
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Reading a GPX file, and cropping its contents to a given area:
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<tt>gpx = GPX::GPXFile.new(:gpx_file => filename) # Read GPX file</tt>
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<tt>bounds = GPX::Bounds.new(params) # Create a rectangular area to crop</tt>
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<tt>gpx.crop(bounds) # Crop it</tt>
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<tt>gpx.write(filename) # Save it</tt>
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Converting a Magellan track log to GPX:
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<tt>if GPX::MagellanTrackLog::is_magellan_file?(filename)</tt>
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<tt> GPX::MagellanTrackLog::convert_to_gpx(filename, "#{filename}.gpx")</tt>
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<tt>end</tt>
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== Notes
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This library was written to bridge the gap between my Garmin Geko
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and my website, WalkingBoss.org (RIP). For that reason, it has always been more of a
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work-in-progress than an attempt at full GPX compliance. The track side of the
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library has seen much more use than the route/waypoint side, so if you're doing
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something with routes or waypoints, you may need to tweak some things.
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Since this code uses XML to read an entire GPX file into memory, it is not
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the fastest possible solution for working with GPX data, especially if you are
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working with tracks from several days or weeks.
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Finally, it should be noted that none of the distance/speed calculation or
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crop/delete code has been tested under International Date Line-crossing
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conditions. That particular part of the code will likely be unreliable if
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you're zig-zagging across 180 degrees longitude routinely.
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