A longer version (I'll try). I assume we all agree that overlapping or not reaching polygons where there is adjacency on the ground is wrong. So how can we properly express adjacency? The simple way is to run two polygons through the same subset of nodes. The advanced is to separate this subset into a single line, which will now belong to two multipolygons. I will try to convince you that using advanced is easier, when it comes to "heavy" objects, like landuse= or natural=. Imagine someone has mapped a forest, with a good detail, precisely following its border with a farmland. Now you want to map this farmland. In the simple way you need to follow all nodes your predessor had drawn, clicking all the nodes, be it 25 nodes or 100. In the advanced way, you don't. You instantly reuse his line for your new polygon. This was a most typical example of benefits that advanced multipolygons provide.
I use them for this all the time. _______________________________________________ Talk-us mailing list Talk-us@openstreetmap.org https://lists.openstreetmap.org/listinfo/talk-us
