Tomas, We just went through a whole discussion about mapping bays as polygons. (see https://lists.openstreetmap.org/pipermail/tagging/2018-November/040911.html) This is a similar one. I was one of the people who promoted converting nodes that describe bays into polygons in order to better represent their true size and provide better label placement. Now, after having to add boundaries to those areas of coastline, I can see the benefits of leaving the nodes as they are and allowing software to place the result labels as best it can. Many on this list didn't favor using multipolygons to outline bays either. Involving polygons does complicate subsequent mapping chores. For example, I was adding a National Park boundary in Alaska. I wanted to conflate it with coastline where I could. So I have this way, the boundary way, that is also shared with a peninsula, and also a portion of named ocean, the Chukchi Sea, a large "bay" of sorts, which is also a multipolygon. Each section of coastline/boundary must now be added separately to these three multipolygons! It's a ton of work.
I stopped using multipolygons to map bays after that. I might use them on occasion to better "illustrate" peninsulas but I won't do that in an area where there's already multipolygon complexity present. As people pointed out in the last discussion, it makes for a ton of extra work and invites errors from novice mappers. I now agree with that view. Dave On Thu, Jan 10, 2019 at 2:56 PM Tomas Straupis <[email protected]> wrote: > > 2019-01-10, kt, 09:06 Martin Koppenhoefer rašė: > > coding the geometry into the db does not necessarily mean creating polygons > > though. > > You could also store just 3 nodes and a hint that these are representing a > > polygon, to store a triangle (for example). > > Sorry, I did not get it. How saving only vertexes is better than > having a polygon (made out of those vertexes)? > > Full geometry is required to be able to calculate label positions on > all scales. For small scales this could be a simple curved line > (calculated from polygon geometry), for large scales it could be a lot > of labels placed/scattered on the same polygon geometry and > approximating (simplifying) such polygon too much would decrease > number of labels placed or labels would be placed outside of an object > which is even worse. > > _______________________________________________ > Tagging mailing list > [email protected] > https://lists.openstreetmap.org/listinfo/tagging -- Dave Swarthout Homer, Alaska Chiang Mai, Thailand Travel Blog at http://dswarthout.blogspot.com _______________________________________________ Tagging mailing list [email protected] https://lists.openstreetmap.org/listinfo/tagging
