What is produced is a smooth track, but with applications like Tyre, it is possible to convert the Google maps route into a "turn-by-turn" file that can be downloaded into your GPS unit. This is done in part by creating a set of via points (similar to waypoints) as needed when there is a turn or a curve. If all goes well, the upcoming via point alerts your GPS to signal a turn. Usually, there is a track along with the via points so that you can see that you are on course. With a route loaded into your GPS, you can get a reading of how far it is to your destination and what your ETA is. Very comforting on a long ride in new territory.
I think that Google did not intend to make available this feature as soon as has come to be the case. They very likely will be introducing their own way of making "turn-by-turn" technology possible. In the meantime, programs like Tyre and others translate the information that is associated with a route shown on your screen into a file that can be downloaded into your GPS.
All of the routes you have seen so far on the Blog have *.gpx files associated with them. These are projected turn-by-turn routes. They undoubtedly have glitches, but for the most part are accurate and can provide something like the "turn-by-turn" experience, including distance and time to destination.
Since we are not in France, however, we can't test them directly. What I intend to do is to test them locally and then edit and emend the ones for France as needed. In the meantime, download these zipped *.gpx files here.
- From Castlenaudry to St-Ferreo Reservoir
- From St-Ferreo Reservoir to Bram (or thereabouts to rendezvous with the boat)
- From Trebes to Lastours and return
- The Minervre Excursion
The most recent GPS units handle lots of waypoints and via points. Older units, such as my Garmin 60Sx, are likely overwhelmed with a route generated by Google Maps for the whole trip, but likely do well with individual (daily) routes. I would welcome testing by canal boaters (and others) on perfecting the "turn-by-turn" experience well before we arrive in France. But the time is coming when cyclists will be able to navigate from a common *.gpx file they have imported into their GPS units (operating from the satellites) or iPhone or Android or Windows phone (operating from cell-tower triangulation).