QGIS/src/core/qgsgeometryvalidator.cpp
2017-12-03 15:12:51 +10:00

425 lines
12 KiB
C++

/***************************************************************************
qgsgeometryvalidator.cpp - geometry validation thread
-------------------------------------------------------------------
Date : 03.01.2012
Copyright : (C) 2012 by Juergen E. Fischer
email : jef at norbit dot de
***************************************************************************
* *
* 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. *
* *
***************************************************************************/
#include "qgis.h"
#include "qgsgeometryvalidator.h"
#include "qgsgeometry.h"
#include "qgslogger.h"
#include "qgsgeos.h"
QgsGeometryValidator::QgsGeometryValidator( const QgsGeometry &geometry, QVector<QgsGeometry::Error> *errors, QgsGeometry::ValidationMethod method )
: mGeometry( geometry )
, mErrors( errors )
, mStop( false )
, mErrorCount( 0 )
, mMethod( method )
{
}
QgsGeometryValidator::~QgsGeometryValidator()
{
stop();
wait();
}
void QgsGeometryValidator::stop()
{
mStop = true;
}
void QgsGeometryValidator::checkRingIntersections(
int p0, int i0, const QgsPolylineXY &ring0,
int p1, int i1, const QgsPolylineXY &ring1 )
{
for ( int i = 0; !mStop && i < ring0.size() - 1; i++ )
{
QgsVector v = ring0[i + 1] - ring0[i];
for ( int j = 0; !mStop && j < ring1.size() - 1; j++ )
{
QgsVector w = ring1[j + 1] - ring1[j];
QgsPointXY s;
if ( intersectLines( ring0[i], v, ring1[j], w, s ) )
{
double d = -distLine2Point( ring0[i], v.perpVector(), s );
if ( d >= 0 && d <= v.length() )
{
d = -distLine2Point( ring1[j], w.perpVector(), s );
if ( d > 0 && d < w.length() &&
ring0[i + 1] != ring1[j + 1] && ring0[i + 1] != ring1[j] &&
ring0[i + 0] != ring1[j + 1] && ring0[i + 0] != ring1[j] )
{
QString msg = QObject::tr( "segment %1 of ring %2 of polygon %3 intersects segment %4 of ring %5 of polygon %6 at %7" )
.arg( i0 ).arg( i ).arg( p0 )
.arg( i1 ).arg( j ).arg( p1 )
.arg( s.toString() );
QgsDebugMsg( msg );
emit errorFound( QgsGeometry::Error( msg, s ) );
mErrorCount++;
}
}
}
}
}
}
void QgsGeometryValidator::validatePolyline( int i, QgsPolylineXY line, bool ring )
{
if ( ring )
{
if ( line.size() < 4 )
{
QString msg = QObject::tr( "ring %1 with less than four points" ).arg( i );
QgsDebugMsg( msg );
emit errorFound( QgsGeometry::Error( msg ) );
mErrorCount++;
return;
}
if ( line[0] != line[ line.size() - 1 ] )
{
QString msg = QObject::tr( "ring %1 not closed" ).arg( i );
QgsDebugMsg( msg );
emit errorFound( QgsGeometry::Error( msg ) );
mErrorCount++;
return;
}
}
else if ( line.size() < 2 )
{
QString msg = QObject::tr( "line %1 with less than two points" ).arg( i );
QgsDebugMsg( msg );
emit errorFound( QgsGeometry::Error( msg ) );
mErrorCount++;
return;
}
int j = 0;
while ( j < line.size() - 1 )
{
int n = 0;
while ( j < line.size() - 1 && line[j] == line[j + 1] )
{
line.remove( j );
n++;
}
if ( n > 0 )
{
QString msg = QObject::tr( "line %1 contains %n duplicate node(s) at %2", "number of duplicate nodes", n ).arg( i ).arg( j );
QgsDebugMsg( msg );
emit errorFound( QgsGeometry::Error( msg, line[j] ) );
mErrorCount++;
}
j++;
}
for ( j = 0; !mStop && j < line.size() - 3; j++ )
{
QgsVector v = line[j + 1] - line[j];
double vl = v.length();
int n = ( j == 0 && ring ) ? line.size() - 2 : line.size() - 1;
for ( int k = j + 2; !mStop && k < n; k++ )
{
QgsVector w = line[k + 1] - line[k];
QgsPointXY s;
if ( !intersectLines( line[j], v, line[k], w, s ) )
continue;
double d = 0.0;
try
{
d = -distLine2Point( line[j], v.perpVector(), s );
}
catch ( QgsException &e )
{
Q_UNUSED( e );
QgsDebugMsg( "Error validating: " + e.what() );
continue;
}
if ( d < 0 || d > vl )
continue;
try
{
d = -distLine2Point( line[k], w.perpVector(), s );
}
catch ( QgsException &e )
{
Q_UNUSED( e );
QgsDebugMsg( "Error validating: " + e.what() );
continue;
}
if ( d <= 0 || d >= w.length() )
continue;
QString msg = QObject::tr( "segments %1 and %2 of line %3 intersect at %4" ).arg( j ).arg( k ).arg( i ).arg( s.toString() );
QgsDebugMsg( msg );
emit errorFound( QgsGeometry::Error( msg, s ) );
mErrorCount++;
}
}
}
void QgsGeometryValidator::validatePolygon( int idx, const QgsPolygonXY &polygon )
{
// check if holes are inside polygon
for ( int i = 1; !mStop && i < polygon.size(); i++ )
{
if ( !ringInRing( polygon[i], polygon[0] ) )
{
QString msg = QObject::tr( "ring %1 of polygon %2 not in exterior ring" ).arg( i ).arg( idx );
QgsDebugMsg( msg );
emit errorFound( QgsGeometry::Error( msg ) );
mErrorCount++;
}
}
// check holes for intersections
for ( int i = 1; !mStop && i < polygon.size(); i++ )
{
for ( int j = i + 1; !mStop && j < polygon.size(); j++ )
{
checkRingIntersections( idx, i, polygon[i], idx, j, polygon[j] );
}
}
// check if rings are self-intersecting
for ( int i = 0; !mStop && i < polygon.size(); i++ )
{
validatePolyline( i, polygon[i], true );
}
}
void QgsGeometryValidator::run()
{
mErrorCount = 0;
switch ( mMethod )
{
case QgsGeometry::ValidatorGeos:
{
char *r = nullptr;
geos::unique_ptr g0( mGeometry.exportToGeos() );
GEOSContextHandle_t handle = QgsGeometry::getGEOSHandler();
if ( !g0 )
{
emit errorFound( QgsGeometry::Error( QObject::tr( "GEOS error: could not produce geometry for GEOS (check log window)" ) ) );
}
else
{
GEOSGeometry *g1 = nullptr;
char res = GEOSisValidDetail_r( handle, g0.get(), GEOSVALID_ALLOW_SELFTOUCHING_RING_FORMING_HOLE, &r, &g1 );
if ( res != 1 )
{
if ( g1 )
{
const GEOSCoordSequence *cs = GEOSGeom_getCoordSeq_r( handle, g1 );
unsigned int n;
if ( GEOSCoordSeq_getSize_r( handle, cs, &n ) && n == 1 )
{
double x, y;
GEOSCoordSeq_getX_r( handle, cs, 0, &x );
GEOSCoordSeq_getY_r( handle, cs, 0, &y );
emit errorFound( QgsGeometry::Error( QObject::tr( "GEOS error: %1" ).arg( r ), QgsPointXY( x, y ) ) );
mErrorCount++;
}
GEOSGeom_destroy_r( handle, g1 );
}
else
{
emit errorFound( QgsGeometry::Error( QObject::tr( "GEOS error: %1" ).arg( r ) ) );
mErrorCount++;
}
GEOSFree_r( handle, r );
}
}
break;
}
case QgsGeometry::ValidatorQgisInternal:
{
QgsWkbTypes::Type flatType = QgsWkbTypes::flatType( mGeometry.wkbType() );
//if ( flatType == QgsWkbTypes::Point || flatType == QgsWkbTypes::MultiPoint )
// break;
if ( flatType == QgsWkbTypes::LineString )
{
validatePolyline( 0, mGeometry.asPolyline() );
}
else if ( flatType == QgsWkbTypes::MultiLineString )
{
QgsMultiPolylineXY mp = mGeometry.asMultiPolyline();
for ( int i = 0; !mStop && i < mp.size(); i++ )
validatePolyline( i, mp[i] );
}
else if ( flatType == QgsWkbTypes::Polygon )
{
validatePolygon( 0, mGeometry.asPolygon() );
}
else if ( flatType == QgsWkbTypes::MultiPolygon )
{
QgsMultiPolygonXY mp = mGeometry.asMultiPolygon();
for ( int i = 0; !mStop && i < mp.size(); i++ )
{
validatePolygon( i, mp[i] );
}
for ( int i = 0; !mStop && i < mp.size(); i++ )
{
if ( mp[i].isEmpty() )
{
emit errorFound( QgsGeometry::Error( QObject::tr( "polygon %1 has no rings" ).arg( i ) ) );
mErrorCount++;
continue;
}
for ( int j = i + 1; !mStop && j < mp.size(); j++ )
{
if ( mp[j].isEmpty() )
continue;
if ( ringInRing( mp[i][0], mp[j][0] ) )
{
emit errorFound( QgsGeometry::Error( QObject::tr( "polygon %1 inside polygon %2" ).arg( i ).arg( j ) ) );
mErrorCount++;
}
else if ( ringInRing( mp[j][0], mp[i][0] ) )
{
emit errorFound( QgsGeometry::Error( QObject::tr( "polygon %1 inside polygon %2" ).arg( j ).arg( i ) ) );
mErrorCount++;
}
else
{
checkRingIntersections( i, 0, mp[i][0], j, 0, mp[j][0] );
}
}
}
}
else if ( flatType == QgsWkbTypes::Unknown )
{
QgsDebugMsg( QObject::tr( "Unknown geometry type" ) );
emit errorFound( QgsGeometry::Error( QObject::tr( "Unknown geometry type %1" ).arg( mGeometry.wkbType() ) ) );
mErrorCount++;
}
if ( mStop )
{
emit errorFound( QgsGeometry::Error( QObject::tr( "Geometry validation was aborted." ) ) );
}
else if ( mErrorCount > 0 )
{
emit errorFound( QgsGeometry::Error( QObject::tr( "Geometry has %1 errors." ).arg( mErrorCount ) ) );
}
#if 0
else
{
emit errorFound( QgsGeometry::Error( QObject::tr( "Geometry is valid." ) ) );
}
#endif
break;
}
}
}
void QgsGeometryValidator::addError( const QgsGeometry::Error &e )
{
if ( mErrors )
*mErrors << e;
}
void QgsGeometryValidator::validateGeometry( const QgsGeometry &geometry, QVector<QgsGeometry::Error> &errors, QgsGeometry::ValidationMethod method )
{
QgsGeometryValidator *gv = new QgsGeometryValidator( geometry, &errors, method );
connect( gv, &QgsGeometryValidator::errorFound, gv, &QgsGeometryValidator::addError );
gv->run();
gv->wait();
}
//
// distance of point q from line through p in direction v
// return >0 => q lies left of the line
// <0 => q lies right of the line
//
double QgsGeometryValidator::distLine2Point( const QgsPointXY &p, QgsVector v, const QgsPointXY &q )
{
if ( qgsDoubleNear( v.length(), 0 ) )
{
throw QgsException( QObject::tr( "invalid line" ) );
}
return ( v.x() * ( q.y() - p.y() ) - v.y() * ( q.x() - p.x() ) ) / v.length();
}
bool QgsGeometryValidator::intersectLines( const QgsPointXY &p, QgsVector v, const QgsPointXY &q, QgsVector w, QgsPointXY &s )
{
double d = v.y() * w.x() - v.x() * w.y();
if ( qgsDoubleNear( d, 0 ) )
return false;
double dx = q.x() - p.x();
double dy = q.y() - p.y();
double k = ( dy * w.x() - dx * w.y() ) / d;
s = p + v * k;
return true;
}
bool QgsGeometryValidator::pointInRing( const QgsPolylineXY &ring, const QgsPointXY &p )
{
bool inside = false;
int j = ring.size() - 1;
for ( int i = 0; !mStop && i < ring.size(); i++ )
{
if ( qgsDoubleNear( ring[i].x(), p.x() ) && qgsDoubleNear( ring[i].y(), p.y() ) )
return true;
if ( ( ring[i].y() < p.y() && ring[j].y() >= p.y() ) ||
( ring[j].y() < p.y() && ring[i].y() >= p.y() ) )
{
if ( ring[i].x() + ( p.y() - ring[i].y() ) / ( ring[j].y() - ring[i].y() ) * ( ring[j].x() - ring[i].x() ) <= p.x() )
inside = !inside;
}
j = i;
}
return inside;
}
bool QgsGeometryValidator::ringInRing( const QgsPolylineXY &inside, const QgsPolylineXY &outside )
{
for ( int i = 0; !mStop && i < inside.size(); i++ )
{
if ( !pointInRing( outside, inside[i] ) )
return false;
}
return true;
}