some change in maptool makes rivers disappear

[zoff99]

rivers seem to be only a thin line. i made 2 screenshots. a) with an older map b) with new map file (same navit svn version)

[korrosa]

As mentioned on IRC: it is my strongest suspicion that this is an error with the OSM data - it looks like a riverbank polygon has been broken or deleted, or perhaps assimilated into a relation?

The thin stretch of river is a way used in OSM to show flow direction, and for major rivers riverbank polygons are used in conjunction to show the width and shape of the river - it looks like this polygon has been messed with somehow...

[korrosa]

I'm happy to report that this is not a Navit issue as such, in-so-far-as nothing has broken with maptool.

If you check the attached image I'll be uploading with this comment, you can see I've selected one of the 'missing' river polygons in JOSM (an editor for OSM). I've brought up the history for that polygon, and you can see that on 5th September 2011 all the key/value pairs were removed. Because there no longer exists a waterway=riverbank key/value pair, maptool doesn't recognise it as a river any longer.

So how does it still render in OSM (​http://www.openstreetmap.org/?lat=48.29724&lon=16.34659&zoom=16&layers=M)? The polygon is part of a multipolygon relation, as shown in the second image I'll be uploading with this comment. You can see that this relation has the key/value pair waterway=riverbank, and the OSM rendering engines (Mapnik et al) recognise this relation. Maptool, unfortunately, does not at this moment.

So, it's not that something broke with maptool, it's just that maptool doesn't yet recognise relations. As there are existing tickets calling for this feature, I'll close this one as invalid.