85 lines
2.2 KiB
C
85 lines
2.2 KiB
C
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/**********************************************************************
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*
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* GEOS - Geometry Engine Open Source
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* http://geos.osgeo.org
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*
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* Copyright (C) 2006 Refractions Research Inc.
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*
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* This is free software; you can redistribute and/or modify it under
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* the terms of the GNU Lesser General Licence as published
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* by the Free Software Foundation.
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* See the COPYING file for more information.
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*
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**********************************************************************
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*
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* Last port: simplify/DouglasPeuckerSimplifier.java rev. 1.5 (JTS-1.7)
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*
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**********************************************************************/
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#pragma once
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#include <geos/export.h>
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#include <memory> // for unique_ptr
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// Forward declarations
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namespace geos {
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namespace geom {
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class Geometry;
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}
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}
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namespace geos {
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namespace simplify { // geos::simplify
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/** \brief
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* Simplifies a Geometry using the standard Douglas-Peucker algorithm.
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*
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* Ensures that any polygonal geometries returned are valid.
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* Simple lines are not guaranteed to remain simple after simplification.
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*
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* Note that in general D-P does not preserve topology -
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* e.g. polygons can be split, collapse to lines or disappear
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* holes can be created or disappear,
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* and lines can cross.
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* To simplify geometry while preserving topology use TopologyPreservingSimplifier.
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* (However, using D-P is significantly faster).
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*
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*/
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class GEOS_DLL DouglasPeuckerSimplifier {
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public:
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static std::unique_ptr<geom::Geometry> simplify(
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const geom::Geometry* geom,
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double tolerance);
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DouglasPeuckerSimplifier(const geom::Geometry* geom);
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/** \brief
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* Sets the distance tolerance for the simplification.
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*
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* All vertices in the simplified geometry will be within this
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* distance of the original geometry.
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* The tolerance value must be non-negative. A tolerance value
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* of zero is effectively a no-op.
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*
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* @param tolerance the approximation tolerance to use
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*/
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void setDistanceTolerance(double tolerance);
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std::unique_ptr<geom::Geometry> getResultGeometry();
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private:
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const geom::Geometry* inputGeom;
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double distanceTolerance;
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};
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} // namespace geos::simplify
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} // namespace geos
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