[mkgmap-dev] Short Arc Problem? Error 3 Mapsource, Problem on Calculating this route Basecamp.

Thu Jan 3 19:47:17 GMT 2013

But I still don't get it fully.
Is the MP creating a new line, or adding the tags?

Because now there would be two conflicting highway keys...

I think it would be good to have a behaviour to only add keys to the 
underlying line, but not overwrite or not double if its a line...
because I don't think I can add a check like:
highway=* & highway=residential & mkgmap:mp_created=true {delete 
highway=residential}

(without deleting both highway keys...).

Are there any cases, where we really need highways from multipolygon in 
case highway already exists on the line itself?
On 03.01.2013 20:17, WanMil wrote:
> Maybe it helps if I explain what happens in detail with the mp:
>
> 1. The mp calculates the tags for the mp. In this case the tags of the 
> mp are used which are [area=yes; highway=residential]
> 2. These mp tags are removed from all outer ways if they are 
> identical. In this case no tag is removed from way 114405617.
> 3. All outer ways are copied and tagged with the mp tags. These copied 
> ways are only processed by the line style file. They can be identified 
> by the additional tag mkgmap:mp_created=true.
> 4. All outer polygons are tagged with the mp tags and are processed by 
> the polygon style file only. They can also be identified by the 
> additional tag mkgmap:mp_created=true.
>
> Point 2 and 3 are required because in OSM the mp *and* the outer ways 
> are tagged quite often.
>
> In this case it creates a residential way (point 3) with identical 
> coords like the tertiary way 114405617.
>
> WanMil
>
>
>> But that change causes problems for other parts. There are some
>> highway=residential areas without ways that cross them, so in order to
>> have routing work in some inner city cases, you must make sure that you
>> route along the edges.
>>
>> If multipolygons were treated the same way as relations, that would make
>> it easier to make sure only one routable highway gets created (because
>> add highway onto highway would not add the highway, because there is
>> already an underlying highway).
>>
>>
>> The only thing I could think that does cause problems, if two routable
>> lines are on top of each other, and both have the same road_type and
>> same road_speed. Maybe there could be a check in the mkgmap continue
>> function, never to create two routable lines on top of each other, if
>> both road_speed and road_type are identical.
>> On 03.01.2013 14:44, Minko wrote:
>>>
>>> The issue also disappears when you use
>>> highway=residential & area!=yes [0x06 road_class=0 road_speed=2 
>>> resolution 22]
>>> instead of the default rule
>>> highway=residential [0x06 road_class=0 road_speed=2 resolution 22]
>>>
>>> So it got to do with those two routable lines on top of each other
>>>
>>>
>>
>

-- 
keep on biking and discovering new trails

Felix
openmtbmap.org & www.velomap.org