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

Thu Feb 22 19:03:08 GMT 2018

Hi Felix,

I can reproduce the problem with a small download around the way and just the --route option.
The problem seems to be in WrongAngleFixer, it says
"... all points of way http://www.openstreetmap.org/way/130665733 are rounded to equal map units"
No idea why the way is not reduced to a single point, will investigate further.

Gerd

________________________________________
Von: mkgmap-dev <mkgmap-dev-bounces at lists.mkgmap.org.uk> im Auftrag von Felix Hartmann <extremecarver at gmail.com>
Gesendet: Donnerstag, 22. Februar 2018 19:27:44
An: Development list for mkgmap
Betreff: [mkgmap-dev] Bug in Road Merging - actually doubling roads.

I just noticed that mkgmap sometimes creates a lot more routable roads for a certain stretch than actually defined in the style-file.

https://www.openstreetmap.org/way/130665733

should be only once as a routable line in my map, however it ends up 6 times!
Once is correct, but 5 iterations are actually the way from the south (3 times) and the way from the East (2 times). Now each of these ways should be created that often, however it should not overlay into this short stretch of way.

While doubling up ways can be beneficial for routing, having a way more than 5 times on top of each other let's Garmin devices crash on routing over them. Also it leads to detours - as it will not always route straight from the Way from South to the Way going to the West, but follow along after the intersection for 4.3m until hitting up north, then reversing and finally going to the way in the West.

I've uploaded the tile here:
https://openmtbmap.org/gmapsupp_copied.img

I'm pretty sure that with other style-files - the way will also be copied past the intersection and end up too often in the map for that 4.3m stretch...

I kinda guess it is related to it being so short - that place has some remarkable micro-mapping detail.
Or is this really expected?

If needed I can try to create a reduced style to only create that problem - but I think the bug should be obvious.

--
Felix Hartman - Openmtbmap.org & VeloMap.org
Schusterbergweg 32/8
6020 Innsbruck
Austria - Österreich