[josm-dev] WMSPlugin Update

Ian Dees ian.dees at gmail.com
Wed Sep 1 17:17:30 BST 2010

2010/9/1 Iván Sánchez Ortega <ivan at sanchezortega.es>

> El día Wednesday 01 September 2010 17:20:53, Ian Dees dijo:
> > My update does check the available CRS from GetCapabilities for each
> layer
> > and will flag a layer as unusable if it doesn't match the current
> > projection set in JOSM's preferences.
> Wait a second there.
> So what if I query a epsg:4326 WMS but JOSM's display is set to EPSG:3857
> spherical mercator?
> AFAIK, JOSM handles this transparently right now... and I wouldn't like to
> see
> that broken.

Unless the plugin is stretching or reprojecting the image locally somehow,
the WMS plugin will have to send the GetMap WMS request with an SRS set to
whatever the projection is in JOSM (which causes the server to send back an
image in the right projection). If JOSM has projection set to Mercator, it
will build the URL with EPSG:3857. ... I think.

Currently, my change to the plugin gives a warning when any of the WMS
layers selected do not support the currently-selected JOSM projection.

The suggestion was to prompt the user to switch JOSM to a projection that
was supported by the WMS server instead of blindly trying to load the GetMap
request (and failing with a red image on the map).

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