render Thames River problem

ellweber · 2008-06-26T17:49:22.000Z

As a new user I have come upon a problem that I am unable to resolve. I would greatly appreciate some guidance.

When I view London using any of the online map viewing tools I see the river correctly rendered:

http://www.openstreetmap.org/?lat=51.5057&lon=-0.1198&zoom=14&layers=B00FTT

However, if I download a .osm file of the same area and convert it to a Garmin compatible .img file it renders quite differently as shown here:

Looking at the xml content of the .osm file I can see that the river is defined as a sequence of nodes that represent the banks with each bank a number of ways separately grouped and tagged as .

When the data is converted with mkgmap to a .img file and displayed on the GPS or displayed with GPSMapEdit each bank segment is rendered as a polygon that includes the bank and a straight line joining the ends. I see this same behavior on maps I have assembled and on the maps I find in the OSM Map On Garmin/Download page.

Interestingly when I look at the Seine it is composed of a sequence of abutting polygons and renders as expected.

Any clue as to what I am doing incorrectly or how to otherwise resolve this would be much appreciated.

Thanks,

Lynn

jamicu · 2008-06-28T12:59:10.000Z

I’m getting exactly the same problem with IMG files downloaded from the webpage where Garmin IMG maps are made available. My GPS reciever is showing exactly the same thing for the location you provided an image of.
Garmin map download
The rest of the Thames is confusing with vast areas of London apparently flooded

I was looking at how the River Thames had been drawn, but can work out if thats where the problem is

ellweber · 2008-07-06T18:49:10.000Z

[quote=jamicu]I’m getting exactly the same problem with IMG files downloaded from the webpage where Garmin IMG maps are made available. My GPS reciever is showing exactly the same thing for the location you provided an image of.
[urlhttp://wiki.openstreetmap.org/index.php/OSM_Map_On_Garmin/Download][/url]
The rest of the Thames is confusing with vast areas of London apparently flooded

I was looking at how the River Thames had been drawn, but can work out if thats where the problem is[/quote]
Thanks for the reply jamicu. I have come to the conclusion that mkgmap is not handling riverbanks correctly when they are composed of segments for the banks rather than polygons for segments of the whole river. I will inquire in the mkgmap discussion area as this doesn’t seem to be the right place to ask! I am a little surprised that we seem to be the only two people that have noticed this but I am sure it will be resolved in due time.

Best regards,

Lynn