qgsinternalgeometryengine.h

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/***************************************************************************
  qgsinternalgeometryengine.h - QgsInternalGeometryEngine
 
 ---------------------
 begin                : 13.1.2016
 copyright            : (C) 2016 by Matthias Kuhn
 email                : matthias@opengis.ch
 ***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/
#ifndef QGSINTERNALGEOMETRYENGINE_H
#define QGSINTERNALGEOMETRYENGINE_H
 
#define SIP_NO_FILE
 
#include <functional>
 
#include "qgspointxy.h"
 
class QgsGeometry;
class QgsAbstractGeometry;
class QgsLineString;
class QgsLineSegment2D;
class QgsFeedback;
 
class QgsInternalGeometryEngine
{
  public:
 
    explicit QgsInternalGeometryEngine( const QgsGeometry &geometry );
 
    QString lastError() const;
 
    QgsGeometry extrude( double x, double y ) const;
 
    QgsGeometry poleOfInaccessibility( double precision, double *distanceFromBoundary = nullptr ) const;
 
    QgsGeometry orthogonalize( double tolerance = 1.0E-8, int maxIterations = 1000, double angleThreshold = 15.0 ) const;
 
    QgsGeometry densifyByCount( int extraNodesPerSegment ) const;
 
    QgsGeometry densifyByDistance( double distance ) const;
 
    QgsGeometry variableWidthBuffer( int segments, const std::function< std::unique_ptr< double[] >( const QgsLineString *line ) > &widthFunction ) const;
 
    QgsGeometry taperedBuffer( double startWidth, double endWidth, int segments ) const;
 
    QgsGeometry variableWidthBufferByM( int segments ) const;
 
    static QVector< QgsPointXY > randomPointsInPolygon( const QgsGeometry &polygon, int count,
        const std::function< bool( const QgsPointXY & ) > &acceptPoint, unsigned long seed = 0, QgsFeedback *feedback = nullptr, int maxTriesPerPoint = 0 );
 
    QgsGeometry convertToCurves( double distanceTolerance, double angleTolerance ) const;
 
    QgsGeometry orientedMinimumBoundingBox( double &area SIP_OUT, double &angle SIP_OUT, double &width SIP_OUT, double &height SIP_OUT ) const;
 
  private:
    const QgsAbstractGeometry *mGeometry = nullptr;
 
    mutable QString mLastError;
};
 
class CORE_EXPORT QgsRay2D
{
  public:
 
    QgsRay2D( const QgsPointXY &origin, QgsVector direction )
      : origin( origin )
      , direction( direction )
    {}
 
    bool intersects( const QgsLineSegment2D &segment, QgsPointXY &intersectPoint ) const;
 
  private:
 
    QgsPointXY origin;
    QgsVector direction;
};
 
 
// adapted for QGIS geometry classes from original work at https://github.com/trylock/visibility by trylock
 
class CORE_EXPORT QgsLineSegmentDistanceComparer
{
  public:
 
    explicit QgsLineSegmentDistanceComparer( const QgsPointXY &origin )
      : mOrigin( origin )
    {}
 
    bool operator()( QgsLineSegment2D ab, QgsLineSegment2D cd ) const;
 
  private:
 
    QgsPointXY mOrigin;
 
};
 
 
// adapted for QGIS geometry classes from original work at https://github.com/trylock/visibility by trylock
 
class CORE_EXPORT QgsClockwiseAngleComparer
{
  public:
    explicit QgsClockwiseAngleComparer( const QgsPointXY &origin )
      : mVertex( origin )
    {}
 
    bool operator()( const QgsPointXY &a, const QgsPointXY &b ) const;
 
  private:
 
    QgsPointXY mVertex;
 
};
 
 
#endif // QGSINTERNALGEOMETRYENGINE_H