[mkgmap-dev] Splitting at country borders?

Sun Sep 20 22:13:01 BST 2009

> neither splitter or osmosis insert new points. but it is required to  
> have boundary nodes in mkgmap. splitter would need to calculate  
> crossing points with the boundary or a provided split polygon with all  
> ways and insert the boundary points.
>   
This is my opinion too. Whatever tool does the splitting into countries, 
it has to create new nodes at the intersection of the roads and the 
state borders.
> you can do the presplit but routing can't work then across boundaries.
> osmosis has different modes
> - clip ways at the boundary -> no routing across tiles due to missing  
> nodes
>   
As I'he written before, I don't know the internals of osmosis. But if I 
the ways are clipped at a border, then it should be possible to create a 
new node at the intersection and mark the node as a border node.
Is there a developper of osmosis reading this list?
>>> Then it would be possilbe to download europe from geofabrik, split it
>>> into countries and then crate maps from it.
>>> These maps would be interroutable. It would be also need less  
>>> computing
>>> power/memory for doing this compared of
>>> processing the whole europe map
>>>       
>> I would expect the interstate routing to work. Precondition is  
>> obviously
>> that the presplitted tiles don't miss any segments at the border and  
>> the
>> border nodes have exactly the same coordinates.
>>
>>     
>
> still don't understand why this is useful. If you want multiple  
> countries and route across countries and tiles why split it more than  
> necessary and try to assemble again?
>
>   
As some other users have written, then it would be possible to download 
the regions of interest from geofabrik and compile them with splitter 
and mkgmap and have a routable map.
Then its not neccessary to download whole europe, when I want only 
bavaria and austria. I could furthermore load the precompiled maps of 
countires onto my etrex, just as I need them.

So I would really appreciate it, if the presplitted maps from geofabrik 
are clipped 'correctly' at the borders.