Pitney Bowes MapInfo Professional - Manual (Page 412)

Enhancing Map Data using a Web Map Service
(WMS)
Web Services can provide more data for you to work with in MapInfo Professional. A Web Map Service
(WMS) allows you to access maps and data through your local intranet or the Internet. This innovation
is based on a specification from the Open GIS Consortium (OGC) that allows you to use raster map
images from servers that also comply with the specification. You must specify the coordinate system
within your data request to ensure that the images you retrieve "sync up" or register with your other map
data.
How Does MapInfo Professional Use WMS Servers?
When you create a .tab file from WMS layer(s), you are actually creating a pointer to an XML file that
keeps track of the data you selected, (the server address, the selected layer(s), the styles, the format,
and the projection settings). You never actually retrieve the data and save it on your computer. Every
time you add a WMS table as a layer to your map or you change the view of the map, the system
generates a map request and retrieves the layer information. To do this, the .tab file points to an XML
file which retrieves the information from the WMS Server and displays it on your computer. If you are
not connected to the Internet, the server is unavailable, or the WMS layer(s) you are retrieving are not
available, you cannot use the WMS .tab file.
The WMS sites that we include in this documentation or in the standard installation of MapInfo
Professional have been verified as part of the testing process. We cannot guarantee that these
sites will remain active, only that they were active as of this writing. Note:
WMS Maps Display in Current Map Window's Coordinate System by Default
Many times, when you are retrieving a WMS map, you are adding it to enhance the detail of a Map
window that you are already working on. We have changed the default behavior of the Projection
drop-down box. Now, this list defaults to the projection that matches the front-most map window, if that
projection is available in the list.
But What if a WMS Definition Already Exists or I am not Working in a Map Window?
• If you are retrieving a WMS map and there was a previous WMS definition (or you are modifying a
WMS map), MapInfo Professional uses the coordinate system that matches the current projection (not
necessarily the Map window's coordinate system).
• If there was no previous WMS definition, the current Map window's coordinate system is selected if it
can be found in the Projection list.
• If the Map window's coordinate system is not in the Projection list or you are retrieving a WMS map
when you are not working in a Map window, MapInfo Professional tries to default to EPSG:4326.
• Finally, if none of these projections are found, the first item in the Projection list is selected.
Supported Image Formats for WMS
MapInfo Professional supports the following image formats for WMS:
• PNG
• JPEG (JPG)
• TIFF (GeoTIFF AND TIFF)
• GIF.
Not every format will be available from every Web Map Service. Note:
MapInfo Professional 12.5 412
Enhancing Map Data using a Web Map Service (WMS)