GetCapabilities
To obtain general information about this WMS
and specific information about the available map layers, users
should invoke the "GetCapabilities" request. The response
generated by "GetCapabilities" consists of an XML document
to be displayed in your browser window. The form of the URL-encoded
request is as follows:
http://atlas.gc.ca/cgi-bin/atlaswms_en?VERSION=1.1.1&request=Getcapabilities&service=wms
The information contained within the resulting XML document
will assist in selecting the layers desired for the creation
of a map. The unique layer names and their description as
well as projection options are also provided in the XML document.
For a list of other available request parameters, please consult
the following document: “OpenGIS®
Web Map Server Interfaces Implementation Specification, Version
1.1.0” .
GetMap
The “GetMap” request is used to produce a map
with Atlas of Canada base layers. Several parameters are required
to form the URL request including: VERSION, REQUEST, SRS,
BBOX, WIDTH, HEIGHT, LAYERS, STYLES and FORMAT. For further
information on these parameters and others, please consult
the on-line document entitled “OpenGIS®
Web Map Server Interfaces Implementation Specification, Version
1.1.1”.
The following URL-encoded string is an example of a functional
GetMap request containing the above-mentioned parameters and
their values: the “version” of WMS used is 1.1.0,
the “request” is GetMap; the “SRS”
(spatial reference system or projection) is expressed as EPSG:42304
(See the list in the Projections section that follows.); the
bounding box (“bbox”) coordinates are: 2750564.75,-936638.5,3583872.5,4673125,
the “width” and “height” parameters
specify a rectangle of pixels 500 by 500 in dimension, the
value of “layers” is the name of the single layer
displayed, wa_15m; a null value is use for the “styles”
parameter as the layer will be displayed using it’s
default styles; and the “format” of the map image
returned is GIF.
http://atlas.gc.ca/cgi-bin/atlaswms_en?VERSION=1.1.1&request=GetMap&SRS=EPSG:42304&BBOX=-2750564.75,-936638.5,3583872.5,4673125&WIDTH=500&HEIGHT=500&LAYERS=wa_15m&STYLES=&FORMAT=GIF
Please note that each parameter is separated by an “&”
and values are assigned using the “=” sign.
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