Talk:Proposed features/lakeshore

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  • I'm sorry, but having not needed to map large lakes or coastlines I don't understand what difference changing a tag value would make if they are still essentially the same thing? Could you expand on the rationale/comments sections a bit, please? EdLoach 10:35, 3 November 2008 (UTC)
  • If I understand your proposal correctly the outline of a lake would be made up of a number of ways tagged as natural=lakeshore, each way starting where the other way ended. The each individual way would not in itself form a closed area, but all the ways taken together would form a closed area. This proposal follows exactly the initial thinking behind the first discussions on the proposal for waterway = riverbank , see discussions. Over the course of much discussion it was pointed out that renders have a problem with this approach, and that in general closed polygons are best for defining areas. In order to get ways tagged as natural=coastline rendered correctly both Mapnik and Tiles@home layers take a different approach to rendering normal OSM features. I am concerned that your proposal for natural = lakeshore will result in lakes which can not be rendered.
However whilst writing the above paragraph I did wonder if it would be possible to keep your proposal , but also to require all the separate ways to be part of a relation which grouped them together. I do not know of the practicalities of this from the rendering point of view, but anyone reviewing this proposal , and / or voting on it, needs to be aware if the issues involved.
After a bit more thought I realised that if it were possible to group collected adjacent ways into a relation, then in fact there might be no need for a new tag of natural = lakeshore, as it is possible the existing tag of natural = lake could still be used. Dmgroom 11:00, 3 November 2008 (UTC)
Seconded. Relations are the way to go. If the feature is small enough, put the tag on the way. Otherwise, use a relation to group individual ways (mutltipolygon) and put the tag on it. Renderers should be smart enough to tell this apart. --Pshunter 23:40, 11 February 2009 (UTC)
  • Change natural=coastline to natural=shore, and use it for both. It's a PITA anyway, but it'd be better than 2 nearly-identical PITA's. Alexrudd 01:40, 14 January 2009 (UTC)