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

112 lines
3.1 KiB
C++

/**********************************************************************
*
* GEOS - Geometry Engine Open Source
* http://geos.osgeo.org
*
* Copyright (c) 2021 Martin Davis
* Copyright (C) 2021 Paul Ramsey <pramsey@cleverelephant.ca>
*
* 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.
*
**********************************************************************/
#pragma once
#include <geos/export.h>
#include <geos/geom/CoordinateSequence.h> // to materialize CoordinateSequence
#include <memory>
#include <vector>
// Forward declarations
namespace geos {
namespace geom {
class Coordinate;
class CoordinateSequence;
class Geometry;
class GeometryFactory;
class LineString;
}
}
using geos::geom::Coordinate;
using geos::geom::CoordinateSequence;
using geos::geom::Geometry;
using geos::geom::GeometryFactory;
using geos::geom::LineString;
namespace geos { // geos.
namespace operation { // geos.operation
namespace buffer { // geos.operation.buffer
/**
* Models a section of a raw offset curve,
* starting at a given location along the raw curve.
* The location is a decimal number, with the integer part
* containing the segment index and the fractional part
* giving the fractional distance along the segment.
* The location of the last section segment
* is also kept, to allow optimizing joining sections together.
*
* @author mdavis
*/
class GEOS_DLL OffsetCurveSection {
private:
std::unique_ptr<CoordinateSequence> sectionPts;
double location;
double locLast;
bool isEndInSameSegment(double nextLoc) const;
public:
OffsetCurveSection(std::unique_ptr<CoordinateSequence> && secPts, double pLoc, double pLocLast)
: sectionPts(std::move(secPts))
, location(pLoc)
, locLast(pLocLast)
{};
const CoordinateSequence* getCoordinates() const;
std::unique_ptr<CoordinateSequence> releaseCoordinates();
double getLocation() const { return location; };
/**
* Joins section coordinates into a LineString.
* Join vertices which lie in the same raw curve segment
* are removed, to simplify the result linework.
*
* @param sections the sections to join
* @param geomFactory the geometry factory to use
* @return the simplified linestring for the joined sections
*/
static std::unique_ptr<Geometry> toLine(
std::vector<std::unique_ptr<OffsetCurveSection>>& sections,
const GeometryFactory* geomFactory);
static std::unique_ptr<Geometry> toGeometry(
std::vector<std::unique_ptr<OffsetCurveSection>>& sections,
const GeometryFactory* geomFactory);
static std::unique_ptr<OffsetCurveSection> create(
const CoordinateSequence* srcPts,
std::size_t start, std::size_t end,
double loc, double locLast);
static bool OffsetCurveSectionComparator(
const std::unique_ptr<OffsetCurveSection>& a,
const std::unique_ptr<OffsetCurveSection>& b);
};
} // namespace geos.operation.buffer
} // namespace geos.operation
} // namespace geos