Mark Burton wrote:

Hi Mark,

...

I'm trying out maps with routing turned on. The routing seems to work fine within a single map tile, it also works fine when I route to a neighbouring tile.

However, if I route across multiple tiles then it always fails. Mapsource just spends ages and then draws a straight line whilst my garmin counts to 100% and says their was a calculation error.

Am I doing something wrong or is this something we are aware of?

I believe that routing across multiple tiles generally works OK.

You don't say anything about how you produced your tiles. Are you using splitter.jar? What options are you using?

Cheers,

Mark

Sorry forgot to add that bit. I'm using splitter on the UK extracts from geofabrik. The most recent trials have used r1099, but before that I was using r1067 and r1072 all with the same results. As I say going from one tile to an adjacent one works; but anything with an intermediate tile fails. I've tried various routes so I believe the problem is general (for me at least!) rather than a specific road that is causing the problem.

Mark Burton wrote:

Hi Mark,

...

Sorry forgot to add that bit. I'm using splitter on the UK extracts from geofabrik.

OK.

...

The most recent trials have used r1099, but before that I was using r1067 and r1072 all with the same results.

OK.

...

As I say going from one tile to an adjacent one works; but anything with an intermediate tile fails. I've tried various routes so I believe the problem is general (for me at least!) rather than a specific road that is causing the problem.

Testing with mapsource on tiled maps of the UK and the Netherlands, I can route across multiple tiles (in one case, I counted 7 tiles).

However, mapsource often gives up when trying to route long distances (especially with the UK map compared to the NL) so I wonder if there's some complexity contstraint that we're not adhering to.

But to answer your original question, multiple tiles can be routed across.

Cheers,

Mark

Thanks for the feedback. I've just done a new map rerunning splitter and mkgmap r1099 again but I get the same problem. At least you've confirmed it should work so I'll try and do some more thorough testing to see if I can pin down what I'm going wrong.

Ralf Kleineisel wrote:

On 07/28/2009 08:04 PM, MarkS wrote:

...

However, if I route across multiple tiles then it always fails. Mapsource just spends ages and then draws a straight line whilst my garmin counts to 100% and says their was a calculation error.

It does work for me. I routed successfully through half of Germany and the Netherlands with a map made with r1065. Used Geofabrik Europe data and mkgmap-splitter.

What are the command line options you used?

These are the command lines I just tried with. java -Xmx1200m -enableassertions -jar ../splitter/splitter.jar --max-nodes=1500000 ../great_britain.osm java -Xmx1200m -jar ../mkgmap-r1099/mkgmap.jar --latin1 --remove-short-arcs --lower-case --preserve-element-order --location-autofill=1 --gmapsupp --route --net --tdbfile -c template.args They seem to improve the situation slightly (it will sometimes route across a whole tile). However, equally it fails to route sometimes even when the start and end are within the same time. For example in the attached gdb file it fails to route from "Cornwall" to "Wales" (same tile). A number of other routes (eg. "Bramley" to "Hol", "Sherfield" to "Hol") also fail to calculate, whereas "M4" to "A1" calculates fine and covers the same sort of tiles. All the routes have been tried in Mapsource (v.6.15.6), altough I've had similar behaviour in 6.13.7. I've also done a bit of experimenting: - My routing preference has been set at the mid point. If I move the slider two notches up towards prefering highways then I don't have a problem. suggesting that it might be complexity of the route. - In a test (on a separate machine) against a Garmin map, the gamin maps had no problem with the routing. - Using splitter with less max-nodes (and therefore more tiles) makes the situation worse. I wonder if it is something to do with minor roads (and inter-tile connections). Maybe they get a higher class on mkgmap than on the garmin maps. This allows more complex routes, which eventually overloads the routing calculation and it fails.

Ralf Kleineisel wrote:

On 07/30/2009 11:25 PM, MarkS wrote:

Thanks for this. I've tried it but it doesn't seem to make much difference. A couple of routes did calculate different (in fact one was a bit odd as it took the M4 across the Severn Bridge and then the A48 up the side of the Severn before joining the M5, rather than just going up the M5). However, whilst some longer distances (over a couple of tiles are working), shorter ones sometimes break (unless within a single tile). Here is what I can tell: - The route is more likely to calculate in mapsource if I prefer highways. Using a garmin map it mapsource will calculate regardless of prefernce. - My Etrex has the same sort of issues (not exactly the same). Routing is more likely to work on quickest calculation than best route. - It isn't distance related (some routes were much longer than others) - It isn't purely crossing tiles (some crossing one tile, or going via another fail). - Cornwall and Mid-Wales seem to have more problems with routing to/from (note: might just be where I placed a marker rather than the whole of the area). It looks a bit as if a route that is more likely to involve minor roads (either because of the area or the preferences) the more likely a problem will occur.