Hi Frederik, On 4/19/11 4:13 AM, Frederik Ramm wrote:
You explain "building=yes" as meaning "is it filled?", when in reality it is completely up to the renderer whether or not to fill an object that is tagged to be a building.
Wait, I don't think I agree with this. That is, to me, the question of whether a 'thingie' in OSM is an area thingie or a line thingie should _not_ be up to the visualization layer. I think I am one of many voices who are saying that we should 'fix' this. (I'm not saying anything that isn't on the wiki already here.)
My concern here is that there are geometric operations you might want to do to "OSM data" without being dependent on interpretation, and you can't always do them if you don't know what you have. Consider tiling the data. If a way is a linear ring surrounding my tile, I can drop it. If it is a polygonal area/point set, I need to crop the point set to the bounded area.
It also seems difficult to provide a 'generic' editor (an editor not specifically tied to a visualization schema) without knowing whether a closed ring is an area or line loop.
This is a problem we do not have with multipolygons (they're always areas) and we certainly do not have with ways vs nodes...just with the special case of close ring rings being areas sometimes.
So Frederik, I agree that the data model, editing and rendering are distinct. But I would like to see the pure 'spatial' interpretation of data be unambiguous in the data model, even if its visualization is highly subjective.
cheers Ben -- Scenery Home Page: http://scenery.x-plane.com/ Scenery blog: http://www.x-plane.com/blog/ Plugin SDK: http://www.xsquawkbox.net/xpsdk/ X-Plane Wiki: http://wiki.x-plane.com/ Scenery mailing list: [email protected] Developer mailing list: [email protected] _______________________________________________ dev mailing list [email protected] http://lists.openstreetmap.org/listinfo/dev
