geo-extension-waypoints

From Microformats Wiki
Jump to navigation Jump to search

Geo Waypoint Trails

An exploration of publishing information about sequences of geographical points using series of Geo (or other) microformats.

Terms

Conceptually, a collection of points, with no sequential relationship (the county towns of England, say, or all skyscrapers in New York), is deemed a collection (or set) of individual Waypoints. A sequentially-ordered collection of points may be expressed as a track or a route. Tracks are a record of where a person has been, routes are suggestions about where they might go in the future. So, for instance, there might be timestamps for each point in a track (because someone is recording where and when they were there), but timestamps for each point in a route are unlikely to be provided, because the author is suggesting it, and nobody might ever have travelled it.

A route which ends at its beginning may also describe a boundary (also called a box or polygon). A boundary may be for an object or area on any scale, from a small building or plot of land to a continent, at any level of granularity.

It may therefore be appropriate to use a sequence of hCalendar microformats for tracks and of hCard microformats for routes, boundaries and waypoints.

The Problem

To allow the publishing of series of waypoints in such a way that they are downloadable and that their ordering is parsable.

Participants

Real-World Examples

Collections

  <tr>
  <td>10</td>
  <td>
    <div class="geo">
      <span class="latitude">52.38616</span><br/>
      <span class="longitude">4.91199</span>
    </div>
  </td>
  <td ><a href="...">Waypoint 10</a></td>
  <td >Amsterdam (3 km) <a title="" href="...">Map</a></td>
  </tr>

Other

  <wpt lat="39.921055008" lon="3.054223107"> 
  <ele>12.863281</ele> 
  <time>2005-05-16T11:49:06Z</time> 
  <name>Cala Sant Vicenç - Mallorca</name> 
  <sym>City</sym> 
  </wpt>

Existing formats

A number of other formats (which route/ track parsers may wish to export) are listed at http://www.gpsbabel.org/capabilities.html

GPS Babel is a free command line utility (there is a gui but it has limited functionality) for converting between these formats.

Typical mandatory attributes

  • Latitude (WSG84, using decimal or degrees-minutes-seconds values)
  • Longitude (ditto)
  • text label

Typical optional attributes

  • timestamp
  • elevation
  • image
  • note ?
  • url ?

Issues

  • How to indicate that a set of waypoints is a specific, but unordered, collection (i.e. a set of all the metro stations in Paris, and another set of all the underground stations in London, may be published on the same page)
    • KML uses "Folder" for each such set. e.g [1]
  • How to sequence routes
    • Perhaps using order in source code, ordered lists, hCalendar or hAtom?
    • We could use hAtom and the feed category to distinguish between ordered, unordered and polygons.
      • hAtom requires both an author and date, neither of which are required for routes or polygons. Andy Mabbett
  • How to timestamp tracks (timestamps imply a chronological sequence)
  • How to differentiate between a route (for example in the shape of a letter "U") and a boundary (or polygon) - in other words, to say whether or not, after the last point, the line returns to the first.
    • Suppose we use class="folder" for a sequence (per KML; see above). We could have class="folder route" or class="folder polygon".
  • What can we learn, or use, from the GPX (XML schema for GPS data) specification?

References

See Also
Retrieved from "http://microformats.org/wiki/index.php?title=geo-extension-waypoints&oldid=21228"