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

94 lines
2.6 KiB
C++

/**********************************************************************
*
* GEOS - Geometry Engine Open Source
* http://geos.osgeo.org
*
* Copyright (C) 2006 Refractions Research Inc.
*
* This is free software; you can redistribute and/or modify it under
* the terms of the GNU Lesser General Licence as published
* by the Free Software Foundation.
* See the COPYING file for more information.
*
**********************************************************************
*
* Last port: simplify/TopologyPreservingSimplifier.java r536 (JTS-1.12+)
*
**********************************************************************
*
* NOTES:
*
**********************************************************************/
#pragma once
#include <geos/export.h>
#include <geos/geom/Geometry.h>
#include <geos/simplify/TaggedLinesSimplifier.h>
#include <memory> // for unique_ptr
#include <map>
#ifdef _MSC_VER
#pragma warning(push)
#pragma warning(disable: 4251) // warning C4251: needs to have dll-interface to be used by clients of class
#endif
namespace geos {
namespace simplify { // geos::simplify
/** \brief
* Simplifies a geometry, ensuring that
* the result is a valid geometry having the
* same dimension and number of components as the input.
*
* The simplification uses a maximum distance difference algorithm
* similar to the one used in the Douglas-Peucker algorithm.
*
* In particular, if the input is an areal geometry
* ( Polygon or MultiPolygon )
*
* - The result has the same number of shells and holes (rings) as the input,
* in the same order
* - The result rings touch at <b>no more</b> than the number of touching point in the input
* (although they may touch at fewer points)
*
*/
class GEOS_DLL TopologyPreservingSimplifier {
public:
static std::unique_ptr<geom::Geometry> simplify(
const geom::Geometry* geom,
double tolerance);
TopologyPreservingSimplifier(const geom::Geometry* geom);
/** \brief
* Sets the distance tolerance for the simplification.
*
* All vertices in the simplified geometry will be within this
* distance of the original geometry.
* The tolerance value must be non-negative. A tolerance value
* of zero is effectively a no-op.
*
* @param tolerance the approximation tolerance to use
*/
void setDistanceTolerance(double tolerance);
std::unique_ptr<geom::Geometry> getResultGeometry();
private:
const geom::Geometry* inputGeom;
std::unique_ptr<TaggedLinesSimplifier> lineSimplifier;
};
} // namespace geos::simplify
} // namespace geos
#ifdef _MSC_VER
#pragma warning(pop)
#endif