Module org.opengis.geoapi

Package org.opengis.referencing.crs

Interface GeneralDerivedCRS

All Superinterfaces:

CoordinateReferenceSystem, IdentifiedObject, ReferenceSystem, SingleCRS

All Known Subinterfaces:

DerivedCRS, ProjectedCRS

@Classifier(ABSTRACT)
@UML(identifier="SC_GeneralDerivedCRS",
     specification=ISO_19111)
public interface GeneralDerivedCRS
extends SingleCRS

A coordinate reference system that is defined by its coordinate conversion from another coordinate reference system. Derived CRS are not directly associated to a datum.

In principle, all sub-types of CoordinateReferenceSystem may take on the role of either source or derived CRS with the exception of a GeocentricCRS and a ProjectedCRS. The latter is modelled as an object class under its own name, rather than as a general derived CRS of type "projected". This has been done to honour common practice, which acknowledges projected CRSs as one of the best known types of coordinate reference systems.

Since:

1.0

Field Summary

Fields inherited from interface IdentifiedObject

ALIAS_KEY, IDENTIFIERS_KEY, NAME_KEY, REMARKS_KEY

Fields inherited from interface ReferenceSystem

DOMAIN_OF_VALIDITY_KEY, SCOPE_KEY

Method Summary

Modifier and Type	Method	Description
CoordinateReferenceSystem	getBaseCRS()	Returns the base coordinate reference system.
Conversion	getConversionFromBase()	Returns the conversion from the base CRS to this CRS.

Methods inherited from interface IdentifiedObject

getAlias, getIdentifiers, getName, getRemarks, toWKT

Methods inherited from interface ReferenceSystem

getDomainOfValidity, getScope

Methods inherited from interface SingleCRS

getCoordinateSystem, getDatum

Method Details

getBaseCRS

@UML(identifier="baseCRS",
     obligation=MANDATORY,
     specification=ISO_19111)
CoordinateReferenceSystem getBaseCRS()

Returns the base coordinate reference system.

Upcoming API change — specialization
According ISO 19111, the return type should be SingleCRS. This change may be applied in GeoAPI 4.0.

Returns:

the base coordinate reference system.

getConversionFromBase

@UML(identifier="conversion",
     obligation=MANDATORY,
     specification=ISO_19111)
Conversion getConversionFromBase()

Returns the conversion from the base CRS to this CRS.

Returns:

the conversion from the base CRS.

Departure from OGC/ISO abstract specification:

Change of name without change in functionality

"conversion" may be confusing as a method name since it does not indicate which CRS is the source or which is the target. The OGC 01-009 specification used the toBase() method name. By analogy with 01-009, GeoAPI defines a method name which contains the "FromBase" expression.