One of the things Dave Earl mentioned in his talk about rendering was the gaps-in-casings you sometimes get at bridges.
What I've ended up doing is 1) rendering casings in layer (not underneath everything like Mapnik) 2) putting in a flag to identify ways that join ways of different layer, with a view to suppressing end caps layer_change=yes (suppress end caps on this way; taken to be implied by bridge=yes; use on ramps down to layer=-1 ways) layer_change=no (enforce end caps on this way; use on bridges that have ramps separately tagged) The traditional layer=0 / layer=1+bridge=yes / layer=0 tagging is unaltered (the renderer sees the bridge=yes and suppresses end caps). The main place you end up changing the tags is for grade-separated junctions, for example: http://www.openstreetmap.org/?lat=51.7557415366173&lon=-1.29630088806152&zoom=18 Here the underpass gets separated into three sections, with layer=0+layer_change=yes ways bracketing a layer=-1 way. The renderer draws the end caps on the layer=-1 way, but suppresses them on the layer_change ways. Also notice that the roundabout is all at layer=0, including the bridges. You can't make the bridges longer at lower zooms, but at least the layer=0 casings stay on top as the underpass gets wider. Good idea, or just a local fix? Richard On Sun, Jul 25, 2010 at 7:56 PM, David Earl <da...@frankieandshadow.com> wrote: > My two talks for State of the Map > * Tag Central - a schema for OpenStreetMap > * What I learned making a real map on real paper for real people and real > money > are now available online at http://www.frankieandshadow.com/sotm10/ > > David > > _______________________________________________ > talk mailing list > t...@openstreetmap.org > http://lists.openstreetmap.org/listinfo/talk > _______________________________________________ Tagging mailing list Tagging@openstreetmap.org http://lists.openstreetmap.org/listinfo/tagging
