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Configuration of a geoDatum is important for the display of map layers in the FEWs Explorer and Grid display. A geoDatum is the coordinate system the extents, or map layers are defined in. Enumeration of of geoDatums of many different coordinate systems are available in Appendix B.
projection
One can use various projections: mercator, web_mercator, orthographic, llxy and gnomonic. In combination with WMS services only (web-) mercator is possible.
defaultExtent
Definition of the default zoom extent.
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