org.opengis.referencing.crs
Interface EngineeringCRS
- All Superinterfaces:
- CoordinateReferenceSystem, IdentifiedObject, ReferenceSystem, SingleCRS
@UML(identifier="SC_EngineeringCRS",
specification=ISO_19111)
public interface EngineeringCRS
- extends SingleCRS
A contextually local coordinate reference system. It can be divided into two broad categories:
- earth-fixed systems applied to engineering activities on or near the surface of the
earth;
- CRSs on moving platforms such as road vehicles, vessels, aircraft, or spacecraft.
Earth-fixed Engineering CRSs are commonly based on a simple flat-earth approximation of the
earth's surface, and the effect of earth curvature on feature geometry is ignored: calculations
on coordinates use simple plane arithmetic without any corrections for earth curvature. The
application of such Engineering CRSs to relatively small areas and "contextually local" is in
this case equivalent to "spatially local".
Engineering CRSs used on moving platforms are usually intermediate coordinate reference
systems that are computationally required to calculate coordinates referenced to
geocentric, geographic or
projected CRSs. These engineering coordinate reference
systems are subject to all the motions of the platform with which they are associated.
In this case "contextually local" means that the associated coordinates are meaningful
only relative to the moving platform. Earth curvature is usually irrelevant and is therefore
ignored. In the spatial sense their applicability may extend from the immediate vicinity of
the platform (e.g. a moving seismic ship) to the entire earth (e.g. in space applications).
The determining factor is the mathematical model deployed in the positioning calculations.
Transformation of coordinates from these moving Engineering CRSs to earth-referenced coordinate
reference systems involves time-dependent coordinate operation parameters.
- Since:
- GeoAPI 1.0
getDatum
@UML(identifier="datum",
obligation=MANDATORY,
specification=ISO_19111)
EngineeringDatum getDatum()
- Returns the datum, which must be an engineering one.
- Specified by:
getDatum
in interface SingleCRS
- Returns:
- The datum.
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