DYT/Tool/OpenSceneGraph-3.6.5/include/geos/triangulate/DelaunayTriangulationBuilder.h

/**********************************************************************
 *
 * 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/DelaunayTriangulationBuilder.java r524
 *
 **********************************************************************/

#pragma once

#include <geos/triangulate/IncrementalDelaunayTriangulator.h>
#include <geos/geom/CoordinateSequence.h>

#include <memory>

namespace geos {
namespace geom {
class Geometry;
class MultiLineString;
class GeometryCollection;
class GeometryFactory;
class Envelope;
}
namespace triangulate {
namespace quadedge {
class QuadEdgeSubdivision;
}
}
}

namespace geos {
namespace triangulate { //geos.triangulate


/** \brief
 * A utility class which creates Delaunay Triangulations
 * from collections of points and extract the resulting
 * triangulation edges or triangles as geometries.
 *
 * @author JTS: Martin Davis
 * @author Benjamin Campbell
 *
 */
class GEOS_DLL DelaunayTriangulationBuilder {
public:
    /**
     * Extracts the unique {@link geom::Coordinate}s from the given
     * {@link geom::Geometry}.
     *
     * @param geom the geometry to extract from
     * @return a List of the unique Coordinates. Caller takes ownership of the returned object.
     */
    static std::unique_ptr<geom::CoordinateSequence> extractUniqueCoordinates(const geom::Geometry& geom);

    /**
     * Converts all {@link geom::Coordinate}s in a collection to
     * {@link quadedge::Vertex}es.
     *
     * @param coords the coordinates to convert
     * @return a List of Vertex objects.
     */
    static IncrementalDelaunayTriangulator::VertexList toVertices(const geom::CoordinateSequence& coords);

    /**
     * Returns a CoordinateSequence containing only the unique coordinates of its input.
     * @param seq a coordinateSequence
     * @return a sorted CoordinateSequence with the unique points of seq.
     */
    static std::unique_ptr<geom::CoordinateSequence> unique(const geom::CoordinateSequence* seq);

private:
    std::unique_ptr<geom::CoordinateSequence> siteCoords;
    double tolerance;
    std::unique_ptr<quadedge::QuadEdgeSubdivision> subdiv;

public:
    /**
     * Creates a new triangulation builder.
     *
     */
    DelaunayTriangulationBuilder();

    ~DelaunayTriangulationBuilder() = default;

    /**
     * Sets the sites (vertices) which will be triangulated.
     * All vertices of the given geometry will be used as sites.
     *
     * @param geom the geometry from which the sites will be extracted.
     */
    void setSites(const geom::Geometry& geom);

    /**
     * Sets the sites (vertices) which will be triangulated
     * from a collection of {@link geom::Coordinate}s.
     *
     * @param coords a CoordinateSequence.
     */
    void setSites(const geom::CoordinateSequence& coords);

    /**
     * Sets the snapping tolerance which will be used
     * to improved the robustness of the triangulation computation.
     * A tolerance of 0.0 specifies that no snapping will take place.
     *
     * @param p_tolerance the tolerance distance to use
     */
    inline void
    setTolerance(double p_tolerance)
    {
        this->tolerance = p_tolerance;
    }

private:
    void create();

public:
    /**
     * Gets the {@link quadedge::QuadEdgeSubdivision} which models the computed triangulation.
     *
     * @return the subdivision containing the triangulation
     */
    quadedge::QuadEdgeSubdivision& getSubdivision();

    /**
     * Gets the edges of the computed triangulation as a {@link geom::MultiLineString}.
     *
     * @param geomFact the geometry factory to use to create the output
     * @return the edges of the triangulation. The caller takes ownership of the returned object.
     */
    std::unique_ptr<geom::MultiLineString> getEdges(const geom::GeometryFactory& geomFact);

    /**
     * Gets the faces of the computed triangulation as a {@link geom::GeometryCollection}
     * of {@link geom::Polygon}.
     *
     * @param geomFact the geometry factory to use to create the output
     * @return the faces of the triangulation. The caller takes ownership of the returned object.
     */
    std::unique_ptr<geom::GeometryCollection> getTriangles(const geom::GeometryFactory& geomFact);

    /**
     * Computes the {@link geom::Envelope} of a collection of
     * {@link geom::Coordinate}s.
     *
     * @param coords a List of Coordinates
     * @return the envelope of the set of coordinates
     */

    static geom::Envelope envelope(const geom::CoordinateSequence& coords);

};

} //namespace geos.triangulate
} //namespace goes