[OSM-talk] Large Rivers in general, mapnik rendering in Particular

[David Groom]

The proposed tag waterway = river, 
http://wiki.openstreetmap.org/index.php/Proposed_features/Large_rivers , has 
been at proposal stage for over 18 months, which seems far too long for a 
tag which represents such an important feature.

The main problem area seems to be that some people do not like the current 
proposal whereby a river is divided up in to separate closed areas.  The 
reason being that the "segment" crossing the river to close the area marks a 
boundary which does not actually exist.  Discussion on this could go on 
indefinitely, but it does really need a Mapnik "expert" to either (i) see if 
there is a way that Mapnik can render areas which are not closed (ie. 
comprised of two parallel ways), or (ii) if this is not , and will never be, 
possible then to state that fact , and we can then have a tag proposal which 
will render in both Mapnik and Tiles at home

The main issue in practice is we now have no standard way of tagging rivers, 
and people are relatively free to do what they like, with the result that 
large portions of the River Thames disappeared from the Mapnik layer 
recently 
http://www.informationfreeway.org/?lat=51.49&lon=0.41&zoom=11&layers=0000F0B0F

David