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

107 lines
3.4 KiB
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/**********************************************************************
*
* GEOS - Geometry Engine Open Source
* http://geos.osgeo.org
*
* Copyright (C) 2012 Excensus LLC.
*
* 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: triangulate/IncrementalDelaunayTriangulator.java r524
*
**********************************************************************/
#pragma once
#include <list>
#include <geos/triangulate/quadedge/Vertex.h>
namespace geos {
namespace triangulate { //geos.triangulate
namespace quadedge {
class QuadEdge;
class QuadEdgeSubdivision;
}
/** \brief
* Computes a Delauanay Triangulation of a set of {@link quadedge::Vertex}es,
* using an incrementatal insertion algorithm.
*
* @author JTS: Martin Davis
* @author Benjamin Campbell
*/
class GEOS_DLL IncrementalDelaunayTriangulator {
private:
quadedge::QuadEdgeSubdivision* subdiv;
bool isUsingTolerance;
bool m_isForceConvex;
public:
/**
* Creates a new triangulator using the given {@link quadedge::QuadEdgeSubdivision}.
* The triangulator uses the tolerance of the supplied subdivision.
*
* @param subdiv
* a subdivision in which to build the TIN
*/
IncrementalDelaunayTriangulator(quadedge::QuadEdgeSubdivision* subdiv);
typedef std::vector<quadedge::Vertex> VertexList;
/**
* Sets whether the triangulation is forced to have a convex boundary. Because
* of the use of a finite-size frame, this condition requires special logic to
* enforce. The default is true, since this is a requirement for some uses of
* Delaunay Triangulations (such as Concave Hull generation). However, forcing
* the triangulation boundary to be convex may cause the overall frame
* triangulation to be non-Delaunay. This can cause a problem for Voronoi
* generation, so the logic can be disabled via this method.
*
* @param isForceConvex true if the triangulation boundary is forced to be convex
*/
void forceConvex(bool isForceConvex);
/**
* Inserts all sites in a collection. The inserted vertices <b>MUST</b> be
* unique up to the provided tolerance value. (i.e. no two vertices should be
* closer than the provided tolerance value). They do not have to be rounded
* to the tolerance grid, however.
*
* @param vertices a Collection of Vertex
*
* @throws LocateFailureException if the location algorithm
* fails to converge in a reasonable number of iterations
*/
void insertSites(const VertexList& vertices);
/**
* Inserts a new point into a subdivision representing a Delaunay
* triangulation, and fixes the affected edges so that the result
* is still a Delaunay triangulation.
* <p>
*
* @return a quadedge containing the inserted vertex
*/
quadedge::QuadEdge& insertSite(const quadedge::Vertex& v);
private:
bool isConcaveBoundary(const quadedge::QuadEdge& e) const;
bool isConcaveAtOrigin(const quadedge::QuadEdge& e) const;
bool isBetweenFrameAndInserted(const quadedge::QuadEdge& e, const quadedge::Vertex& vInsert) const;
};
} //namespace geos.triangulate
} //namespace goes