Multipolygon Post Processing

The reasoning for Multipolygon Post Processing is as follows:

1. I import a closed way tagged landuse=wood and create a polygon.
2. I import a closed way tagged natural=water and create a polygon.
3. I import a relation that has the first way as "outer" and the second as "inner". I now either have to remove the polygon from 1, replacing it with one that has a hole defined by 2, or else I have to delay polygon creation until after all relations are read.

Not really - the outer way should not have the landuse tag, because

• tags on the outer way apply to the whole covered area including any holes
• tags on the relation apply to the multipolygon (the area excluding the outer holes)

Hum, http://wiki.openstreetmap.org/wiki/Multipolygon suggests, the outer way may have tags on its own that would then apply to the relation. Need to check how osm2pgsql handles this..