Module org.opengis.geoapi

Package org.opengis.referencing.cs

Interface CartesianCS

All Superinterfaces:

AffineCS, CoordinateSystem, IdentifiedObject

@UML(identifier="CS_CartesianCS",
     specification=ISO_19111)
public interface CartesianCS
extends AffineCS

A 2- or 3-dimensional coordinate system with orthogonal straight axes. All axes shall have the same length unit of measure.

This type of CS can be used by coordinate reference systems of type GeocentricCRS, ProjectedCRS, EngineeringCRS or ImageCRS. The following examples describe some possible set of axes for Cartesian CS used with the above-cited CRS:

Example 1: used with a Projected CRS

Axis name	Abbr.	Direction	Unit
Easting	E	AxisDirection.EAST	metre
Northing	N	AxisDirection.NORTH	metre

Example 2: used with a Geocentric CRS

Axis name	Abbr.	Direction	Unit
Geocentric X	X	AxisDirection.GEOCENTRIC_X	metre
Geocentric Y	Y	AxisDirection.GEOCENTRIC_Y	metre
Geocentric Z	Z	AxisDirection.GEOCENTRIC_Z	metre

Example 3: used with an Engineering CRS for a station fixed to Earth

Axis name	Abbr.	Direction	Unit
Site north	x	AxisDirection.SOUTH_EAST	metre
Site east	y	AxisDirection.SOUTH_WEST	metre

Example 4: used with an Engineering CRS for a moving platform

Axis name	Abbr.	Direction	Unit
Ahead	x	AxisDirection.valueOf("FORWARD")	metre
Right	y	AxisDirection.valueOf("STARBOARD")	metre
Down	z	AxisDirection.DOWN	metre

Note: the above example uses two axis directions that are not defined in ISO 19111, but found in ISO 19162 as "forward" and "starboard".

Since:

1.0

See Also:

• CSAuthorityFactory.createCartesianCS(String)
• CSFactory.createCartesianCS(Map, CoordinateSystemAxis, CoordinateSystemAxis)
• CSFactory.createCartesianCS(Map, CoordinateSystemAxis, CoordinateSystemAxis, CoordinateSystemAxis)

Departure from OGC/ISO abstract specification:

Departure due to constraint of the Java language

ISO 19111 defines CartesianCS as a direct sub-type of CoordinateSystem. ISO also defines ImageCS as the union of AffineCS and CartesianCS, for use by ImageCRS. Because the union construct found in some languages like C/C++ does not exist in Java, GeoAPI defines CartesianCS as a sub-type of AffineCS in order to achieve the same type safety. With this change, GeoAPI can use AffineCS directly without the need to define ImageCS. In this hierarchy, CartesianCS is considered a special case of AffineCS where all axes are perpendicular to each other.

Field Summary

Fields inherited from interface IdentifiedObject

ALIAS_KEY, IDENTIFIERS_KEY, NAME_KEY, REMARKS_KEY

Method Summary

Methods inherited from interface CoordinateSystem

getAxis, getDimension

Methods inherited from interface IdentifiedObject

getAlias, getIdentifiers, getName, getRemarks, toWKT