DYT/Tool/OpenSceneGraph-3.6.5/include/geos/linearref/LocationIndexOfPoint.h
2024-12-25 07:49:36 +08:00

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/**********************************************************************
*
* GEOS - Geometry Engine Open Source
* http://geos.osgeo.org
*
* Copyright (C) 2011 Sandro Santilli <strk@kbt.io>
* Copyright (C) 2005-2006 Refractions Research Inc.
* Copyright (C) 2001-2002 Vivid Solutions Inc.
*
* This is free software; you can redistribute and/or modify it under
* the terms of the GNU Lesser General Public Licence as published
* by the Free Software Foundation.
* See the COPYING file for more information.
*
**********************************************************************
*
* Last port: linearref/LinearGeometryBuilder.java r466
*
**********************************************************************/
#pragma once
#include <geos/geom/Coordinate.h>
#include <geos/geom/Geometry.h>
#include <geos/linearref/LinearLocation.h>
namespace geos {
namespace linearref { // geos::linearref
/** \brief
* Computes the LinearLocation of the point on a linear [Geometry](@ref geom::Geometry)
* nearest a given [Coordinate](@ref geom::Coordinate).
*
* The nearest point is not necessarily unique; this class always computes
* the nearest point closest to the start of the geometry.
*/
class LocationIndexOfPoint {
private:
const geom::Geometry* linearGeom;
LinearLocation indexOfFromStart(const geom::CoordinateXY& inputPt, const LinearLocation* minIndex) const;
public:
static LinearLocation indexOf(const geom::Geometry* linearGeom, const geom::CoordinateXY& inputPt);
static LinearLocation indexOfAfter(const geom::Geometry* linearGeom, const geom::CoordinateXY& inputPt,
const LinearLocation* minIndex);
LocationIndexOfPoint(const geom::Geometry* linearGeom);
/** \brief
* Find the nearest location along a linear [Geometry](@ref geom::Geometry)
* to a given point.
*
* @param inputPt the coordinate to locate
* @return the location of the nearest point
*/
LinearLocation indexOf(const geom::CoordinateXY& inputPt) const;
/** \brief
* Find the nearest LinearLocation along the linear [Geometry](@ref geom::Geometry)
* to a given [Coordinate](@ref geom::Coordinate) after the specified minimum LinearLocation.
*
* If possible the location returned will be strictly greater than the
* `minLocation`.
* If this is not possible, the value returned will equal `minLocation`.
* (An example where this is not possible is when `minLocation = [end of line]`).
*
* @param inputPt the coordinate to locate
* @param minIndex the minimum location for the point location
* @return the location of the nearest point
*/
LinearLocation indexOfAfter(const geom::CoordinateXY& inputPt, const LinearLocation* minIndex) const;
};
}
}