[mkgmap-dev] Bug in Road Merging - actually doubling roads.

Tue Mar 20 16:30:26 GMT 2018

Hi Felix,

well, up to now I thought that you want to fix the problem in your style and just need help to find out where it happens.
I still don't understand why your style adds so many routable lines, in my eyes this is an errpr on your side.
But you may be right, mkgmap might be able to change the bearing values of an arc when there are too many equal ones.
You never told me what exactly I should do to reproduce a problem. In previous posts you wrote about crashes, now you
mention broken routing. I guess this still only happens on the device?

Gerd

________________________________________
Von: mkgmap-dev <mkgmap-dev-bounces at lists.mkgmap.org.uk> im Auftrag von Felix Hartmann <extremecarver at gmail.com>
Gesendet: Dienstag, 20. März 2018 13:23:37
An: Development list for mkgmap
Betreff: Re: [mkgmap-dev] Bug in Road Merging - actually doubling roads.

well I think if ways are overlapping which have identical nodes it should be possible to throw away according to say this prinicple:
a) identical tags (except name which is not important) - throw away the copy/copies. I think here it is clear the copies are not needed.
b) identical tags (except name) plus more tags.
Eg way 1 has: key1=a key2=b     way 2 has key1=a, key2=b key3=c. So throw away way1.
If there is however
way 1 has: key1=a key2=b  key3=c    way 2 has key1=a, key2=b key4=d. it is more complicated but it could still be merged to a single way consisting of key1=a, key2=b, key3=c, key4=d
if
way 1 has: key1=a key2=b  key3=c    way 2 has key1=a, key2=b key3=d we could keep both ways, or throw away one of them - but yeah then it is not clear which one so better keep.

For the problems related to  http://www.openstreetmap.org/browse/way/310376420
and the other 2 ways. Following a) removes one copy. Following rule b) would actually get rid of the second copy and now information/detail will be lost.

I'll try the new patch and see if I can find out more about problems.

BTW - would it not be better to just use a test map for finding the error? I'm pretty sure any 6 routable roads on top of each other (identical direction) cause routing to break on Oregon 600. As soon as some way is slightly different angle - it is fine.