org.geolatte.geom

Class MeasureInterpolatingVisitor

java.lang.Object

org.geolatte.geom.MeasureInterpolatingVisitor

All Implemented Interfaces:

GeometryVisitor

public class MeasureInterpolatingVisitor
extends Object
implements GeometryVisitor

A GeometryVisitor that derives a Geometry by interpolating on the measure values of the visited Geometries.

TODO -- rewrite (is copied from SQL/MM specs)

Interpolation is used to determine any points on the 1-dimensional geometry with an m coordinate value between SM and EM inclusively. The implementation-defined interpolation algorithm is used to estimate values between measured values, usually using a mathematical function. For example, given a measure of 6 and a 2-point linestring where the m coordinate value of the start point is 4 and the m coordinate value of the end point is 8, since 6 is halfway between 4 and 8, the interpolation algorithm would be a point on the linestring halfway between the start and end points. The interpolation is within a line segment and not across line segments in an ST_Curve. The interpolation is within an ST_Curve element and not across ST_Curve elements in an ST_MultiCurve. The results are produced in a geometry collection. If there are consecutive points in the 1-dimensional geometry with an m coordinate value between SM and EM inclusively, then a curve value element is added to the geometry collection to represent the curve elements between these consecutive points. Any disconnected points in the 1-dimensional geometry value with m coordinate values between SM and EM inclusively are also added to the geometry collection. If no matching m coordinate values are found, then an empty set of type ST_Point is returned.

Author:

Karel Maesen, Geovise BVBA creation-date: 4/10/12

Constructor Summary

Constructors

Constructor and Description
MeasureInterpolatingVisitor(Geometry geometry, double startMeasure, double endMeasure)

Method Summary

Modifier and Type	Method and Description
Geometry	result()
void	visit(GeometryCollection collection) Visits a GeometryCollection.
void	visit(LinearRing linearRing) Visits a LinearRing.
void	visit(LineString lineString) Visits a LineString.
void	visit(Point point) Visits a Point
void	visit(Polygon polygon) Visits a Polygon.
void	visit(PolyHedralSurface surface) Visits a PolyHedralSurface.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

MeasureInterpolatingVisitor

public MeasureInterpolatingVisitor(Geometry geometry,
                                   double startMeasure,
                                   double endMeasure)

Method Detail

visit

public void visit(Point point)

Description copied from interface: GeometryVisitor

Visits a Point

Specified by:

visit in interface GeometryVisitor

visit

public void visit(LineString lineString)

Description copied from interface: GeometryVisitor

Visits a LineString.

Specified by:

visit in interface GeometryVisitor

visit

public void visit(Polygon polygon)

Description copied from interface: GeometryVisitor

Visits a Polygon.

Specified by:

visit in interface GeometryVisitor

visit

public void visit(GeometryCollection collection)

Description copied from interface: GeometryVisitor

Visits a GeometryCollection.

The collection will pass the visitor to it constituent parts.

Specified by:

visit in interface GeometryVisitor

visit

public void visit(LinearRing linearRing)

Description copied from interface: GeometryVisitor

Visits a LinearRing.

Specified by:

visit in interface GeometryVisitor

visit

public void visit(PolyHedralSurface surface)

Description copied from interface: GeometryVisitor

Visits a PolyHedralSurface.

Specified by:

visit in interface GeometryVisitor

result

public Geometry result()