[talk-au] JOSM multipolygon how-to?

[stevea]

To be sure everyone reading knows, JOSM's buffer has amazing undo capacity, I believe "all the way back to the beginning of the session."  And there's the fact you can edit, edit, play with things all day and night long, then you simply do not upload to the OSM servers (and into the fabric of our map).  That's a delightfully clear boundary and when you decide you DO want to upload your changes, JOSM wraps doing that up quite nicely (with the way it prompts for changeset comments, et cetera).

Good editor, JOSM.  I can't like it enough!  (Meaning I'm crazy-enthusiastic for it).

OSM data structures nutshell:  there are nodes, ways, closed ways (polygons) and relations.  Relations can be routes, boundaries, multipolygons, special_econonmic_zones, aboriginal_lands...these values are around 18 and they are all slightly different, with different rules about what's on the role tags and similar but pretty simple stuff.  Keep all that straight (it does take practice) and you've technically mastered writing data into OSM (at a volunteer Contributor level).  There's more to mastering OSM than that, but such technical mastery is a great start and even a pretty tall perch from which to further survey the OSM landscape.  It's a bit like "I can fly."

Have fun mapping, everybody.