- All Superinterfaces:
Conversion
,CoordinateOperation
,IdentifiedObject
,SingleOperation
- All Known Subinterfaces:
ConicProjection
,CylindricalProjection
,PlanarProjection
A conversion transforming
(longitude,latitude) coordinates to Cartesian coordinates
(x,y). Although some map projections can be represented as a
geometric process, in general a map projection is a set of formulae that converts geodetic
latitude and longitude to plane (map) coordinates. Height plays no role in this process,
which is entirely two-dimensional. The same map projection can be applied to many
geographic CRSs, resulting in many
projected CRSs each of which is related
to the same geodetic datum as the
geographic CRS on which it was based.
An unofficial list of projections and their parameters can
be found there.
Most projections expect the following parameters:
"semi_major"
(mandatory),
"semi_minor"
(mandatory),
"central_meridian"
(default to 0),
"latitude_of_origin"
(default to 0),
"scale_factor"
(default to 1),
"false_easting"
(default to 0) and
"false_northing"
(default to 0).
- Since:
- 1.0
- See Also:
- Departure from OGC/ISO abstract specification:
Addition of element not in the ISO/OGC specification
This interface is not part of the ISO specification. It has been added in GeoAPI at user request, in order to provide a way to know the kind of map projection.
-
Field Summary
Fields inherited from interface CoordinateOperation
COORDINATE_OPERATION_ACCURACY_KEY, DOMAIN_OF_VALIDITY_KEY, OPERATION_VERSION_KEY, SCOPE_KEY
Fields inherited from interface IdentifiedObject
ALIAS_KEY, IDENTIFIERS_KEY, NAME_KEY, REMARKS_KEY
-
Method Summary
Modifier and TypeMethodDescriptionReturns the source CRS, which must be geographic ornull
.Returns the target CRS, which must be projected ornull
.Methods inherited from interface Conversion
getOperationVersion
Methods inherited from interface CoordinateOperation
getCoordinateOperationAccuracy, getDomainOfValidity, getMathTransform, getScope
Methods inherited from interface IdentifiedObject
getAlias, getIdentifiers, getName, getRemarks, toWKT
Methods inherited from interface SingleOperation
getMethod, getParameterValues
-
Method Details
-
getSourceCRS
CoordinateReferenceSystem getSourceCRS()Returns the source CRS, which must be geographic ornull
.Upcoming API change — specialization
The source CRS of a map projection is alwaysGeographicCRS
. This change may be applied in GeoAPI 4.0.- Specified by:
getSourceCRS
in interfaceConversion
- Specified by:
getSourceCRS
in interfaceCoordinateOperation
- Returns:
- the source CRS, or
null
if not available. - See Also:
-
getTargetCRS
CoordinateReferenceSystem getTargetCRS()Returns the target CRS, which must be projected ornull
.Upcoming API change — specialization
The target CRS of a map projection is alwaysProjectedCRS
. This change may be applied in GeoAPI 4.0.- Specified by:
getTargetCRS
in interfaceConversion
- Specified by:
getTargetCRS
in interfaceCoordinateOperation
- Returns:
- the target CRS, or
null
if not available. - See Also:
-