GeoCalc Projection Tab

The GeoCalc Projection tab allows Global Mapper users administrative control of geodetic parameters through Geographic Calculator*. Once enabled, Global Mapper will access the Geographic Calculator datasource (GeoCalc Library) for data re projection and coordinate transformations.

On GeoCalc Projection tab, options are available to perform a Projection change or Coordinate Transformation (including Vertical), using the Geographic Calculator datasource.

By default, this tab will display the current Coordinate System, Datum, Units, Vertical Reference and Vertical Units. Changing these values will initiate a Projection change or a Coordinate Transformation.

To save any changes made to the data's Projection, or to perform a Coordinate System/Datum Transformation, hit the Apply button after configuring the Coordinate System, Datum, Units, and Vertical Reference.

Load Projection From File... this may be used to load a coordinate system contained with in a Projection (.prj), .txt or Esri aux.xml file format.

Save Projections To File... this may be used to save coordinate systems to a Projection (.prj), .txt or Esri aux.xml file format.

Coord Transforms: When a coordinate transformation is performed, the transformation from Geographic Calculator will populate in this window. Right-clicking on the transformation line allows for the details of the source layer coordinate system, or the transformation currently being used for that layer to be viewed. Double clicking on a transformation line allows for alteration of the currently selected transformation applied to that specific layer.

For more information on any of the Coordinate Systems, Units or Datums available hit the blue 'I' button next to that field. This will bring up a description from the Geographic Calculator datasource (See below).