[mkgmap-dev] Routing across multiple tiles

Fri Jul 31 15:16:15 BST 2009

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.