Interface Ellipsoid

All Superinterfaces:

@UML(identifier="Ellipsoid", specification=ISO_19111) public interface Ellipsoid extends IdentifiedObject
Geometric figure that can be used to describe the approximate shape of a planet. For the Earth the ellipsoid is bi-axial with rotation about the polar axis. For other planet, the ellipsoid may be tri-axial. An ellipsoid requires two or three defining parameters: For some applications, for example small-scale mapping in atlases, a spherical approximation of the geoid's surface is used, requiring only the radius of the sphere to be specified.
See Also:
Departure from OGC/ISO standard due to constraint of the Java language ISO 19111 defines the union named secondDefiningParameter as being either semiMinorAxis or inverseFlattening. The union construct (defined in some languages like C/C++) does not exist in Java. GeoAPI changed the interface to require both ellipsoidal parameters (in addition to the semiMajorAxis parameter which is mandatory in any case), as was done in OGC 01-009. However, implementers could readily permit users to only provide one of the two parameters by creating a class which calculates the second parameter from the first. For precision, GeoAPI imports the isIvfDefinitive attribute from OGC 01-009 to enable the user to establish which of the two parameters was used to define the instance.