Gnomic Projection

The Gnomic projection is used for plotting great circle arcs as straight lines on a map. Scale, shape and area are badly distorted along these paths, but the great circle routes are precise in relation to the sphere.

The "Gnomic" Projection has the following Parameters:

Parameter Name

Parameter String

Units

Longitude of the Center of the Projection

central_meridian

AngularValue

Latitude of the Origin of the Projection

latitude_of_origin

AngularValue

Radius of the Sphere

spherical_radius

LinearValue

False Easting

false_easting

LinearValue

False Northing

false_northing

LinearValue

Note: If the spherical_radius parameter is set to a value greater than zero, then it will be used as the radius of the sphere.  If this parameter is set to a value less than or equal to zero, then the SemiMajor radius of the Ellipsoid will be used as the radius of the sphere.