DESCRIPTION

r.in.wms handles all of downloading and importing raster data from an OGC WMS web mapping server. It need only be told the desired data to collect (bounds and resolution) via a region, the server to get the data from, and the layer or layers to get. It downloads the data in tiles, reprojects it, imports it, and patches it back together.

NOTES

By default data is downloaded to $GISDBASE/wms_download. This can be changed by setting the folder option when using r.in.wms.

To understand the data you are getting it is necessary to look at the capabilities of the WMS server. This should be available via a capabilities request. This is an example capabilities request to NASA's OnEarth server.

Other brain-dead servers will not accept queries in the form of POST data. If you get an error try using the -g flag to force r.in.wms to send an atomic GET request instead.

EXAMPLES

General Get Capabilities Request

A capabilities request like http://mapserver.flightgear.org/ms?Service=WMS&Version=1.1.1&request=GetCapabilities is where you should start. It tells you what data is offered, the projections it is in, where to find meta data, resolutions, scales, and bounds for data, etc. For example lists the layers available from TelaScience's OSGeo/FlightGear landcover server.


r.in.wms mapserver="http://mapserver.flightgear.org/ms" -l

Land Cover

In a Lat/Lon location first set the region to cover the state of North Carolina and the resolution to 30 arc-seconds.

g.region -p n=37N s=33N w=85W e=75W res=0:00:30
r.in.wms output=nc_landcover mapserver="http://mapserver.flightgear.org/ms" \
         layer=LANDCOVER format=png

North Carolina landcover map

DRG from Terraserver server download

Set the resolution to 1.2 meters for DRGs. Their native resolution is 2.4 meters, so this is some pretty hefty oversampling:

g.region res=1.2 -ap
g.region save=drg-resolution

r.in.wms output=terraserver-drg mapserver="http://terraserver.microsoft.com/ogcmap6.ashx" \
         layers=DRG region=drg-resolution format=jpeg srs=EPSG:26910

Downloads digital raster graphics from Microsoft TerraServer. Note that srs will need to be changed to a projection that is appropriate for your region.

REQUIRED PROGRAMS

r.in.wms requires the following programs to work:

wget: An http download program, or
curl: Alternate http download program
bc: A calculator program
sed, grep: Unix string processing and search programs
gdalwarp: A reprojection tool, needed only if data is projected into this location.
xml2: An xml parser. Enables more accurate listing of layers on the server.

AUTHORS

Soeren Gebbert, Jachym Cepicky, and Cedric Shock

Last changed: $Date$