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

70 lines
1.8 KiB
C++

/**********************************************************************
*
* GEOS - Geometry Engine Open Source
* http://geos.osgeo.org
*
* 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 <memory>
#include <geos/geom/Coordinate.h>
#include <geos/geom/CoordinateSequence.h>
#include <geos/constants.h>
using geos::geom::Coordinate;
using geos::geom::CoordinateSequence;
namespace geos {
namespace simplify { // geos::simplify
class LinkedRing
{
private:
const CoordinateSequence& m_coord;
std::size_t m_size;
std::vector<std::size_t> m_next;
std::vector<std::size_t> m_prev;
static std::vector<std::size_t> createNextLinks(std::size_t size);
static std::vector<std::size_t> createPrevLinks(std::size_t size);
public:
LinkedRing(const CoordinateSequence& cs)
: m_coord(cs)
, m_size(cs.size()-1)
, m_next(createNextLinks(m_size))
, m_prev(createPrevLinks(m_size))
{};
std::size_t size() const;
std::size_t next(std::size_t i) const;
std::size_t prev(std::size_t i) const;
const Coordinate& getCoordinate(std::size_t index) const;
const Coordinate& prevCoordinate(std::size_t index) const;
const Coordinate& nextCoordinate(std::size_t index) const;
bool hasCoordinate(std::size_t index) const;
void remove(std::size_t index);
std::unique_ptr<CoordinateSequence> getCoordinates() const;
}; // LinkedRing
} // geos::simplify
} // geos