org.opengis.geometry.primitive

Interface Curve

All Superinterfaces:

GenericCurve, Geometry, OrientableCurve, OrientablePrimitive, Primitive, TransfiniteSet

@UML(identifier="GM_Curve",
     specification=ISO_19107)
public interface Curve
extends OrientableCurve, GenericCurve

Curve with a positive orientation. Curve is a descendent subtype of Primitive through OrientablePrimitive. It is the basis for 1-dimensional geometry. A curve is a continuous image of an open interval and so could be written as a parameterized function such as c(t):(a, b) → En where "t" is a real parameter and Eⁿ is Euclidean space of dimension n (usually 2 or 3, as determined by the coordinate reference system). Any other parameterization that results in the same image curve, traced in the same direction, such as any linear shifts and positive scales such as e(t) = c(a + t(b-a)):(0,1) → En, is an equivalent representation of the same curve. For the sake of simplicity, Curves should be parameterized by arc length, so that the parameterization operation inherited from GenericCurve will be valid for parameters between 0 and the length of the curve.

Curves are continuous, connected, and have a measurable length in terms of the coordinate system. The orientation of the curve is determined by this parameterization, and is consistent with the tangent function, which approximates the derivative function of the parameterization and shall always point in the "forward" direction. The parameterization of the reversal of the curve defined by c(t):(a, b) → En would be defined by a function of the form s(t) = c(a + b - t):(a, b) → En.

A curve is composed of one or more curve segments. Each curve segment within a curve may be defined using a different interpolation method. The curve segments are connected to one another, with the end point of each segment except the last being the start point of the next segment in the segment list.

Since:

GeoAPI 1.0

Author:

Martin Desruisseaux (IRD)

See Also:

PrimitiveFactory.createCurve(java.util.List<org.opengis.geometry.primitive.CurveSegment>)

Method Summary

Modifier and Type	Method and Description
OrientableCurve[]	getProxy() Returns the orientable curves associated with this curve.
List<? extends CurveSegment>	getSegments() Lists the components curve segments of Curve, each of which defines the direct position of points along a portion of the curve.

Methods inherited from interface OrientableCurve

getBoundary, getComposite, getPrimitive

Methods inherited from interface OrientablePrimitive

getOrientation

Methods inherited from interface Primitive

getComplexes, getContainedPrimitives, getContainingPrimitives

Methods inherited from interface Geometry

clone, distance, getBuffer, getCentroid, getClosure, getConvexHull, getCoordinateDimension, getCoordinateReferenceSystem, getDimension, getEnvelope, getMaximalComplex, getMbRegion, getPrecision, getRepresentativePoint, isCycle, isMutable, isSimple, toImmutable, transform, transform

Methods inherited from interface TransfiniteSet

contains, contains, difference, equals, intersection, intersects, symmetricDifference, union

Methods inherited from interface GenericCurve

asLineString, forConstructiveParam, forParam, getEndConstructiveParam, getEndParam, getEndPoint, getParamForPoint, getStartConstructiveParam, getStartParam, getStartPoint, getTangent, length, length

Method Detail

getSegments

@Association(value="Segmentation")
 @UML(identifier="segment",
     obligation=MANDATORY,
     specification=ISO_19107)
List<? extends CurveSegment> getSegments()

Lists the components curve segments of Curve, each of which defines the direct position of points along a portion of the curve. The order of the curve segments is the order in which they are used to trace this Curve. For a particular parameter interval, the Curve and CurveSegment agree.

Returns:

The list of curve segments. Should never be null neither empty.

See Also:

CurveSegment.getCurve(), Surface.getPatches()

getProxy

@Association(value="Oriented")
 @UML(identifier="proxy",
     obligation=MANDATORY,
     specification=ISO_19107)
OrientableCurve[] getProxy()

Returns the orientable curves associated with this curve.

Specified by:

getProxy in interface Primitive

Returns:

The orientable curves as an array of length 2.

See Also:

OrientableCurve.getPrimitive()