[josm-dev] WMS load/save support

[Frederik Ramm]

Hi,

   I just announced on talk that the latest WMS plugin has primitive
load and save support.

This works by simply using the built-in Java serializing support to
save images to disk and load them from there.

My implementation is quite rough; for example you can only save a full
WMS layer, not individual tiles, and to load the file you need to have
a layer already because loading is from the layer context menu (so I
added a "blank layer" command to the WMS menu). It also doesn't work
on OSGB layers and is likely to horribly break if you change your
projection settings between saving and loading.

Also, it would be nice if one could influence the amount of detail
stored - currently it uses PNG output streams which consume a lot of
disk space. I think it would also be nice to store the individual
files in a structure that can be read by other programs (e.g. a "zip"
file with one control text file that contains metadata, and one jpg or
png file for each WMS tile loaded) - currently it's Java serialization
mumble that nobody else can read.

The WMS plugin should also have some sort of tile management where you
can not only move tiles around but also delete them.

Also, I think we might have to add a function to the "view" menu so
that it is possible to zoom to the extent of a WMS layer, and we might
want to make it possible to load a WMS layer file right away from the
start screen (currently you have to load OSM data or use the "new"
button first).

If anyone is willing and able to improve the WMS plugin along these
lines (or whatever else he likes)... please do! The plugin is not
really actively maintained by anyone, but heavily used by many mappers
every day so this would surely be a good chance to make the community
happy.

Ah, yes, and we might have to find a way for the WMS plugin to detect
whether you have loaded YWMS data and disable saving in that case, or
at least show a big bright warning to tell people they should not save
Yahoo! data.
   
Bye
Frederik

-- 
Frederik Ramm  ##  eMail frederik at remote.org  ##  N49°00.09' E008°23.33'