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Garmin nRoute plots straight-line routes only. Why?
t1d
I am new to nRoute, but an extensive Streets & Trips user.
I had another post regarding navigation in Liberia and Russia.
According to those recommendations, I have:
1) Successfully installed BaseCamp
2) Successfully installed OSM-Routable Map for Liberia
3) Successfully installed nRoute
4) Successfully installed GPSGate
5) Successfully integrated to BU-353 receiver

BaseCamp and nRoute, both, are failing to route along roads between two waypoints in Liberia.

Map is supposed to be routable. Preferences are set to automatic routing (i.e., not direct routing.)

Suggestions? Thanks in advance!
Ken in Regina
Have you tried routes in other locations on the map to make sure the map is really routable. The symptoms you describe usually mean there is no routing data between the two points or you have direct routing preference (which you don't).

...ken...
t1d
Ahhh, Ken, it is sooo good to know that I have a very gracious expert to help me!

I have tested with other waypoints and you are on point. Other waypoints will route by road. I have narrowed down the culprit and it seems to be the airport and the surrounding area. The Airport has two map-provided waypoints for the Airport. However, neither of the two will route by road.

These points are on the Airport complex and do not lie directly on any road. Thinking the lack of contact with a road to be the problem, I created a waypoint on the nearest road. This waypoint did not route by road, either. So, I suspect that:
1) I have corrupted map data, or
2) This area was never built for road routing.

I am thinking of uninstalling/reinstalling the map. You had me do a precise order for the orginal installs. Is there anything that I need to know for the order of the map reinstall?

Thanks sooo much for your good help!
Attached Images
spriggs-airport.jpg  
Ken in Regina
Now that all the programs are installed and working, your only concern is the maps. Just remove and reinstall the maps. Don't mess with anything else.

There is nothing you can do to corrupt the map data by making waypoints and routes so forget about that possibility.

Odds are best that the routing data is simply missing from the airport area and reinstalling is probably a waste of time.

Before reinstalling the maps you might just want to do a little more testing. Find two points on roads in the general vicinity of the airport that will route properly between them. Obviously make sure they have at least one turn between them so you know they are routing properly. Then start sneeking one of the points closer to the airport and recalculating the route. Repeat until it breaks.

And keep in mind that you always get what you pay for.

..... I guess I should clarify that I'm not criticising either the map or your attempt to use it. It's just a hint to not get your expectations too high. That way you won't be too disappointed when you encounter the occasional minor hiccup. And so you won't waste a bunch of time trying to troubleshoot or "fix" something when the most likely answer is simply that the map has a few flaws. Enjoy what works, work around what you can and forget the little that you can't.

...ken...
t1d
Thanks for the 411, Ken... I did a bit of additional testing this afternoon. The break in the data is a bit farther away from the airport than what I thought. Just not quite sure where, yet. I got some very odd simulations. While running the GPS simulator and having nRoute simulate a (misconfigured) straight-line route, the vehicle would switch back and forth between the crow's-flight-line and roads.

And, you are very much correct about price and value. Yep, I need to keep my expectations realistic. But, in contrast, when I was first getting into laptop/gps, I returned Delorme's Street Atlas because it had a break in the map data at the entrance to our neighborhood, rendering it useless. I have been a veerryyy happy S&T user, ever since.

I will post my findings...

Thank you, yet again!
t1d
I did the reinstall and things seem to be improved. Many more POIs showing, so the first map install must have not gone well. Still experiencing some quirks in routing... I think that is a combination of the data and my nRoute learning curve.

All in all, I am impressed and think it will serve nicely for my purposes.

Thanks, again!
Ken in Regina
It's good to hear you got an improvement. It's really quite amazing what you can do with some of the free stuff that is available if you are willing to add a bit of sweat equity.

...ken...
t1d
To quote Radar O'Rielly from the sitcom Mash, "Ahhh, Bach!" Part of what I thought was continued quirky routing may actually be that this map is routing for left-side drivers. However, I think Liberian's drive on the right side of the road.

My Liberia map came from OSM/Lambertus. I would appreciate someone cross-checking me.

Thumbnail Attached - Drive from right to left on Jaimaca Road... Turn left/south on divided road... The route is on the left side of the divided road, going south...
Attached Images
left-side.jpg  
mihermano
My 2c.
Hi. Using nRoute and OSM maps it may be easier to place Waypoints at all of your stops, and route from Waypoint to Waypoint. In the Route Properties dialogue (in nRoute), just need to click "Activate" or "Recalculate" to force the auto routing. When actually navigating with the GPSr connected, possibly right-click on a point and "Route to it".

Looks like dodgy autorouting on the Liberia map is due to some divided roads and connecting roads not being connected properly to create a routing pathway. Autorouting worked OK on visible OSM roads and streets here (including the Monrovia airport road), but some connections are broken so shorter trips should theoretically return fewer map errors.
Cheers.
Attached Images
heres-one-break-700.jpg  
t1d
Hi, mihermano,

Thanks for your research work. It seems to confirm my thinking.

I would appreciate knowing the location/Lat/Lon of the particular break that you note in your thumbnail. I may attempt to report it to OSM's. Thanks in advance for this help.

Edit: I found the location in the small print of the thumbnail: N6 20.963 W10 47.257

Editx2: I have (attempted) to report the error through:
http://osmbugs.org/
I hope this was the proper way to report the error...

Editx3: Followings mihermano's lead, I scrolled through some more of the map and posted some more errors at OSMBugs. I finally found so many that I made this general post:
I mean no disrespect to the hard work that has been done to create this map, but it should be reviewed in its entirety for broken roads and intersections, I have only marked a few that I noticed. Maybe remove its description of "Routable" until then. I am using nRoute on a laptop.
mihermano
Hi. It really needs someone on the ground there to check which breaks are legitimate road features and which are mistakes. There have been quite a few edits in the data recently so it *should* all be corrected eventually, maybe. I guess many hands make light work.
Cheers.
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