qgsgeometryutils.h

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/***************************************************************************
                        qgsgeometryutils.h
  -------------------------------------------------------------------
Date                 : 21 Nov 2014
Copyright            : (C) 2014 by Marco Hugentobler
email                : marco.hugentobler at sourcepole dot com
 ***************************************************************************
 *                                                                         *
 *   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 QGSGEOMETRYUTILS_H
#define QGSGEOMETRYUTILS_H

#include <limits>

#include "qgis_core.h"
#include "qgis.h"
#include "qgspoint.h"


class QgsLineString;

class CORE_EXPORT QgsGeometryUtils
{
  public:

    static QVector<QgsLineString *> extractLineStrings( const QgsAbstractGeometry *geom ) SIP_FACTORY;

    static QgsPoint closestVertex( const QgsAbstractGeometry &geom, const QgsPoint &pt, QgsVertexId &id SIP_OUT );

    static QgsPoint closestPoint( const QgsAbstractGeometry &geometry, const QgsPoint &point );

    static double distanceToVertex( const QgsAbstractGeometry &geom, QgsVertexId id );

    static bool verticesAtDistance( const QgsAbstractGeometry &geometry,
                                    double distance,
                                    QgsVertexId &previousVertex SIP_OUT,
                                    QgsVertexId &nextVertex SIP_OUT );

    static double sqrDistance2D( const QgsPoint &pt1, const QgsPoint &pt2 );

    static double sqrDistToLine( double ptX, double ptY, double x1, double y1, double x2, double y2, double &minDistX SIP_OUT, double &minDistY SIP_OUT, double epsilon );

    static bool lineIntersection( const QgsPoint &p1, QgsVector v1, const QgsPoint &p2, QgsVector v2, QgsPoint &intersection SIP_OUT );

    static bool segmentIntersection( const QgsPoint &p1, const QgsPoint &p2, const QgsPoint &q1, const QgsPoint &q2, QgsPoint &intersectionPoint SIP_OUT, bool &isIntersection SIP_OUT, const double tolerance = 1e-8, bool acceptImproperIntersection = false );

    static bool lineCircleIntersection( const QgsPointXY &center, const double radius,
                                        const QgsPointXY &linePoint1, const QgsPointXY &linePoint2,
                                        QgsPointXY &intersection SIP_INOUT );

    static QgsPoint projectPointOnSegment( const QgsPoint &p, const QgsPoint &s1, const QgsPoint &s2 )
    {
      double nx = s2.y() - s1.y();
      double ny = -( s2.x() - s1.x() );
      double t = ( p.x() * ny - p.y() * nx - s1.x() * ny + s1.y() * nx ) / ( ( s2.x() - s1.x() ) * ny - ( s2.y() - s1.y() ) * nx );
      return t < 0. ? s1 : t > 1. ? s2 : QgsPoint( s1.x() + ( s2.x() - s1.x() ) * t, s1.y() + ( s2.y() - s1.y() ) * t );
    }

    struct SelfIntersection SIP_SKIP
    {
      int segment1;
      int segment2;
      QgsPoint point;
    };

    static QVector<SelfIntersection> selfIntersections( const QgsAbstractGeometry *geom, int part, int ring, double tolerance ) SIP_SKIP;

    static int leftOfLine( double x, double y, double x1, double y1, double x2, double y2 );

    static QgsPoint pointOnLineWithDistance( const QgsPoint &startPoint, const QgsPoint &directionPoint, double distance );

    static double ccwAngle( double dy, double dx );

    static void circleCenterRadius( const QgsPoint &pt1, const QgsPoint &pt2, const QgsPoint &pt3, double &radius SIP_OUT,
                                    double &centerX SIP_OUT, double &centerY SIP_OUT );

    static bool circleClockwise( double angle1, double angle2, double angle3 );

    static bool circleAngleBetween( double angle, double angle1, double angle2, bool clockwise );

    static bool angleOnCircle( double angle, double angle1, double angle2, double angle3 );

    static double circleLength( double x1, double y1, double x2, double y2, double x3, double y3 );

    static double sweepAngle( double centerX, double centerY, double x1, double y1, double x2, double y2, double x3, double y3 );

    static bool segmentMidPoint( const QgsPoint &p1, const QgsPoint &p2, QgsPoint &result SIP_OUT, double radius, const QgsPoint &mousePos );

    static double circleTangentDirection( const QgsPoint &tangentPoint, const QgsPoint &cp1, const QgsPoint &cp2, const QgsPoint &cp3 );

    static void segmentizeArc( const QgsPoint &p1, const QgsPoint &p2, const QgsPoint &p3,
                               QgsPointSequence SIP_PYALTERNATIVETYPE( QVector<QgsPoint> ) &points SIP_OUT, double tolerance = M_PI_2 / 90,
                               QgsAbstractGeometry::SegmentationToleranceType toleranceType = QgsAbstractGeometry::MaximumAngle,
                               bool hasZ = false, bool hasM = false );

    static int segmentSide( const QgsPoint &pt1, const QgsPoint &pt3, const QgsPoint &pt2 );

    static double interpolateArcValue( double angle, double a1, double a2, double a3, double zm1, double zm2, double zm3 );

    static QgsPointSequence pointsFromWKT( const QString &wktCoordinateList, bool is3D, bool isMeasure ) SIP_SKIP;

    static void pointsToWKB( QgsWkbPtr &wkb, const QgsPointSequence &points, bool is3D, bool isMeasure ) SIP_SKIP;

    static QString pointsToWKT( const QgsPointSequence &points, int precision, bool is3D, bool isMeasure ) SIP_SKIP;

    static QDomElement pointsToGML2( const QgsPointSequence &points, QDomDocument &doc, int precision, const QString &ns ) SIP_SKIP;

    static QDomElement pointsToGML3( const QgsPointSequence &points, QDomDocument &doc, int precision, const QString &ns, bool is3D ) SIP_SKIP;

    static QString pointsToJSON( const QgsPointSequence &points, int precision ) SIP_SKIP;

    static double normalizedAngle( double angle );

    static double lineAngle( double x1, double y1, double x2, double y2 );

    static double angleBetweenThreePoints( double x1, double y1, double x2, double y2,
                                           double x3, double y3 );

    static double linePerpendicularAngle( double x1, double y1, double x2, double y2 );

    static double averageAngle( double x1, double y1, double x2, double y2, double x3, double y3 );

    static double averageAngle( double a1, double a2 );

    static QPair<QgsWkbTypes::Type, QString> wktReadBlock( const QString &wkt ) SIP_SKIP;

    static QStringList wktGetChildBlocks( const QString &wkt, const QString &defaultType = QString() ) SIP_SKIP;

    static QgsPoint midpoint( const QgsPoint &pt1, const QgsPoint &pt2 );

    static QgsPointXY interpolatePointOnLine( double x1, double y1, double x2, double y2, double fraction );

    static QgsPoint interpolatePointOnLine( const QgsPoint &p1, const QgsPoint &p2, double fraction );

    static QgsPointXY interpolatePointOnLineByValue( double x1, double y1, double v1, double x2, double y2, double v2, double value );

    static double gradient( const QgsPoint &pt1, const QgsPoint &pt2 );

    static void coefficients( const QgsPoint &pt1, const QgsPoint &pt2,
                              double &a SIP_OUT, double &b SIP_OUT, double &c SIP_OUT );

    static QgsLineString perpendicularSegment( const QgsPoint &p, const QgsPoint &s1, const QgsPoint &s2 );

    static bool setZValueFromPoints( const QgsPointSequence &points, QgsPoint &point );

    enum ComponentType SIP_SKIP
    {
      Vertex,
      Ring,
      Part
    };

    template<class T> static double closestSegmentFromComponents( T &container, ComponentType ctype, const QgsPoint &pt, QgsPoint &segmentPt,  QgsVertexId &vertexAfter, int *leftOf, double epsilon ) SIP_SKIP
    {
      double minDist = std::numeric_limits<double>::max();
      double minDistSegmentX = 0.0, minDistSegmentY = 0.0;
      QgsVertexId minDistVertexAfter;
      int minDistLeftOf = 0;
      double sqrDist = 0.0;
      int vertexOffset = 0;
      int ringOffset = 0;
      int partOffset = 0;

      for ( int i = 0; i < container.size(); ++i )
      {
        sqrDist = container.at( i )->closestSegment( pt, segmentPt, vertexAfter, leftOf, epsilon );
        if ( sqrDist >= 0 && sqrDist < minDist )
        {
          minDist = sqrDist;
          minDistSegmentX = segmentPt.x();
          minDistSegmentY = segmentPt.y();
          minDistVertexAfter = vertexAfter;
          minDistVertexAfter.vertex = vertexAfter.vertex + vertexOffset;
          minDistVertexAfter.part = vertexAfter.part + partOffset;
          minDistVertexAfter.ring = vertexAfter.ring + ringOffset;
          if ( leftOf )
          {
            minDistLeftOf = *leftOf;
          }
        }

        if ( ctype == Vertex )
        {
          //-1 because compoundcurve counts duplicated vertices of neighbour curves as one node
          vertexOffset += container.at( i )->nCoordinates() - 1;
        }
        else if ( ctype == Ring )
        {
          ringOffset += 1;
        }
        else if ( ctype == Part )
        {
          partOffset += 1;
        }
      }

      if ( minDist == std::numeric_limits<double>::max() )
        return -1;  // error: no segments

      segmentPt.setX( minDistSegmentX );
      segmentPt.setY( minDistSegmentY );
      vertexAfter = minDistVertexAfter;
      if ( leftOf )
      {
        *leftOf = minDistLeftOf;
      }
      return minDist;
    }
};

#endif // QGSGEOMETRYUTILS_H