Hello, >From http://mapserver.org/mapfile/projection.html
I get this: "(...) To set up projections you must define one projection object for the output image (in the MAP object) and one projection object for each layer (in the LAYER objects) to be projected. (..) Think of the MAP-level projection object as your output projection. The EXTENT and UNITS values at the MAP-level must be in the output projection units. Also, if you have layers in other projections (other than the MAP-level projection) then you must define PROJECTION objects for those layers, to tell MapServer what projections they are in." Ok, pretty clear so far. Mapserver will render one or more data layers. Each data layer will have its own projection, and this is specified in the PROJECTION property of the layer object. The layers will be render to a image map with another projection. This projection is specified in the PROJECTION property of the MAP object, at highest level. This is the output projection. Now, I want to serve my maps under WMS protocol. http://mapserver.org/ogc/wms_server.html#setup-a-mapfile-for-your-wms So, I need to define a MAP PROJECTION. And that projection will be used to generate a BoundingBox tag for the GetCapabilities XML response. But, my first question: Is this the projection in which the data will be rendered? What about if I want to serve my data in different projections? Do I need to specify several PROJECTION objects at MAP level? I guess not, because I read: "(...) it is often impossible to find an EPSG code to match the projection of your data. In those cases, the “wms_srs” metadata is used to list one or more EPSG codes that the data can be served in, and the PROJECTION object contains the real PROJ4 definition of the data’s projection" So, if I understood, I specify the output projections I offer for my data in "wms_srs" at WEB object level. But then, why do I need a PROJECTION object at MAP level? I specified the projection of all my input data in each LAYER object. Or other way: - My input data projection is defined at LAYER level - The output projections offered are specified in "wms_srs" at WEB level Then,,, why do I need PROJECTION object at MAP level when I want to configure my WMS server? Sorry for the basic questions, and many thanks in advance Best regards, -- Jorge Arévalo Internet & Mobility Division, DEIMOS [email protected] http://es.linkedin.com/in/jorgearevalo80 http://mobility.grupodeimos.com/ http://gis4free.wordpress.com http://geohash.org/ezjqgrgzz0g _______________________________________________ mapserver-users mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/mapserver-users
