[OSM-newbies] mapping islands of a salt flat

[Richard Weait]

On Thu, Nov 24, 2011 at 1:03 PM, Alexandros Papadopoulos
<alexandros.papadopoulos at gmail.com> wrote:
> On 24 November 2011 13:38, Craig Wallace <craigw84 at fastmail.fm> wrote:
>> On 24/11/2011 15:33, Alexandros Papadopoulos wrote:
>>>
>>> Hello.
>>>
>>> I am mapping the islands of the Salar de Uyuni
>>> (http://osm.org/go/NK_7Jv--) as I found it particularly annoying they
>>> were not on the map when I needed this information.

[ ... ]

>> Islands in inland water need to mapped with multipolygon relations. ie map
>> the island as an area, and add it to a multipolygon relation with role
>> "inner", and add the outline of the lake to the relation with role "outer".
>> I see that Isla Incahuasi is already mapped with a multipolygon relation, so
>> you can add all of the other islands to the same relation, with role inner
>> for each.
>>
>> There is no need to tag the islands with natural=land. It is more useful to
>> tag what is actually there. eg if the island is covered with trees then tag
>> it with natural=wood, or if its a beach tag it as natural=beach etc.
>
> Thanks Craig.
>
> So to sum up:
>
> 1. Mark the island as an area.
> 2. Add any useful designations (natural=beach etc)
> 3. Add to multipolygon relation.
>
> I have attempted to do just that for the 20odd islands I can see on
> Bing aerial photography, hope I did the right thing.

Almost perfect, Alex.

As Craig said, once these new polygon islands are added to the
multipolygon relation for the salt flat, you must assign the island a
"role" in the multipolygon relation.

in potlatch, select the island way
in the advanced tab, double click the relation number to open the
relation dialogue box.
select the members panel in the relations dialogue
add "inner" for the role of the island ways.
then save your changes as usual.

You are almost there!  Keep trying. :-)