QGIS/src/core/qgsgeometryvalidator.cpp
2020-10-16 12:18:33 +10:00

475 lines
15 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"
#include "qgsgeometrycollection.h"
#include "qgspolygon.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 QgsLineString *ring0, int p1, int i1, const QgsLineString *ring1 )
{
for ( int i = 0; !mStop && i < ring0->numPoints() - 1; i++ )
{
const double ring0XAti = ring0->xAt( i );
const double ring0YAti = ring0->yAt( i );
QgsVector v( ring0->xAt( i + 1 ) - ring0XAti, ring0->yAt( i + 1 ) - ring0YAti );
for ( int j = 0; !mStop && j < ring1->numPoints() - 1; j++ )
{
const double ring1XAtj = ring1->xAt( j );
const double ring1YAtj = ring1->yAt( j );
QgsVector w( ring1->xAt( j + 1 ) - ring1XAtj, ring1->yAt( j + 1 ) - ring1YAtj );
double sX;
double sY;
if ( intersectLines( ring0XAti, ring0YAti, v, ring1XAtj, ring1YAtj, w, sX, sY ) )
{
double d = -distLine2Point( ring0XAti, ring0YAti, v.perpVector(), sX, sY );
if ( d >= 0 && d <= v.length() )
{
d = -distLine2Point( ring1XAtj, ring1YAtj, w.perpVector(), sX, sY );
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, %8" )
.arg( i0 ).arg( i ).arg( p0 )
.arg( i1 ).arg( j ).arg( p1 )
.arg( sX ).arg( sY );
QgsDebugMsg( msg );
emit errorFound( QgsGeometry::Error( msg, QgsPointXY( sX, sY ) ) );
mErrorCount++;
}
}
}
}
}
}
void QgsGeometryValidator::validatePolyline( int i, const QgsLineString *line, bool ring )
{
if ( !line )
return;
if ( ring )
{
if ( line->numPoints() < 4 )
{
QString msg = QObject::tr( "ring %1 with less than four points" ).arg( i );
QgsDebugMsgLevel( msg, 2 );
emit errorFound( QgsGeometry::Error( msg ) );
mErrorCount++;
return;
}
if ( !line->isClosed() )
{
QString msg = QObject::tr( "ring %1 not closed" ).arg( i );
QgsDebugMsgLevel( msg, 2 );
emit errorFound( QgsGeometry::Error( msg ) );
mErrorCount++;
return;
}
}
else if ( line->numPoints() < 2 )
{
QString msg = QObject::tr( "line %1 with less than two points" ).arg( i );
QgsDebugMsgLevel( msg, 2 );
emit errorFound( QgsGeometry::Error( msg ) );
mErrorCount++;
return;
}
std::unique_ptr< QgsLineString > noDupes;
// test for duplicate nodes, and if we find any flag errors and then remove them so that the subsequent
// tests work OK.
const QVector< QgsVertexId > duplicateNodes = line->collectDuplicateNodes( 1E-8 );
if ( !duplicateNodes.empty() )
{
noDupes.reset( line->clone() );
for ( int j = duplicateNodes.size() - 1; j >= 0; j-- )
{
const QgsVertexId duplicateVertex = duplicateNodes.at( j );
const QgsPointXY duplicationLocation = noDupes->vertexAt( duplicateVertex );
noDupes->deleteVertex( duplicateVertex );
int n = 1;
// count how many other points exist at this location too
for ( int k = j - 1; k >= 0; k-- )
{
const QgsVertexId prevDupe = duplicateNodes.at( k );
const QgsPoint prevPoint = noDupes->vertexAt( prevDupe );
if ( qgsDoubleNear( duplicationLocation.x(), prevPoint.x(), 1E-8 ) && qgsDoubleNear( duplicationLocation.y(), prevPoint.y(), 1E-8 ) )
{
noDupes->deleteVertex( prevDupe );
n++;
}
else
{
break;
}
}
j -= n - 1;
QString msg = QObject::tr( "line %1 contains %n duplicate nodes starting at vertex %2", "number of duplicate nodes", n + 1 ).arg( i + 1 ).arg( duplicateVertex.vertex - n + 1 );
QgsDebugMsgLevel( msg, 2 );
emit errorFound( QgsGeometry::Error( msg, duplicationLocation ) );
mErrorCount++;
}
line = noDupes.get();
}
for ( int j = 0; !mStop && j < line->numPoints() - 3; j++ )
{
const double xAtJ = line->xAt( j );
const double yAtJ = line->yAt( j );
QgsVector v( line->xAt( j + 1 ) - xAtJ, line->yAt( j + 1 ) - yAtJ );
double vl = v.length();
int n = ( j == 0 && ring ) ? line->numPoints() - 2 : line->numPoints() - 1;
for ( int k = j + 2; !mStop && k < n; k++ )
{
const double xAtK = line->xAt( k );
const double yAtK = line->yAt( k );
QgsVector w( line->xAt( k + 1 ) - xAtK, line->yAt( k + 1 ) - yAtK );
double sX;
double sY;
if ( !intersectLines( xAtJ, yAtJ, v, xAtK, yAtK, w, sX, sY ) )
continue;
double d = 0.0;
try
{
d = -distLine2Point( xAtJ, yAtJ, v.perpVector(), sX, sY );
}
catch ( QgsException &e )
{
Q_UNUSED( e )
QgsDebugMsg( "Error validating: " + e.what() );
continue;
}
if ( d < 0 || d > vl )
continue;
try
{
d = -distLine2Point( xAtK, yAtK, w.perpVector(), sX, sY );
}
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, %5" ).arg( j ).arg( k ).arg( i ).arg( sX ).arg( sY );
QgsDebugMsgLevel( msg, 2 );
emit errorFound( QgsGeometry::Error( msg, QgsPointXY( sX, sY ) ) );
mErrorCount++;
}
}
}
void QgsGeometryValidator::validatePolygon( int idx, const QgsPolygon *polygon )
{
// check if holes are inside polygon
for ( int i = 0; !mStop && i < polygon->numInteriorRings(); ++i )
{
if ( !ringInRing( static_cast< const QgsLineString * >( polygon->interiorRing( i ) ), static_cast< const QgsLineString * >( polygon->exteriorRing() ) ) )
{
QString msg = QObject::tr( "ring %1 of polygon %2 not in exterior ring" ).arg( i + 1 ).arg( idx );
QgsDebugMsg( msg );
emit errorFound( QgsGeometry::Error( msg ) );
mErrorCount++;
}
}
// check holes for intersections
for ( int i = 0; !mStop && i < polygon->numInteriorRings(); i++ )
{
for ( int j = i + 1; !mStop && j < polygon->numInteriorRings(); j++ )
{
checkRingIntersections( idx, i + 1, qgsgeometry_cast< QgsLineString * >( polygon->interiorRing( i ) ),
idx, j + 1, qgsgeometry_cast< QgsLineString * >( polygon->interiorRing( j ) ) );
}
}
// check if rings are self-intersecting
validatePolyline( 0, qgsgeometry_cast< const QgsLineString * >( polygon->exteriorRing() ), true );
for ( int i = 0; !mStop && i < polygon->numInteriorRings(); i++ )
{
validatePolyline( i + 1, qgsgeometry_cast< const QgsLineString * >( polygon->interiorRing( i ) ), true );
}
}
void QgsGeometryValidator::run()
{
mErrorCount = 0;
if ( mGeometry.isNull() )
{
return;
}
switch ( mMethod )
{
case QgsGeometry::ValidatorGeos:
{
// avoid calling geos for trivial point geometries
if ( QgsWkbTypes::geometryType( mGeometry.wkbType() ) == QgsWkbTypes::PointGeometry )
{
return;
}
QgsGeos geos( mGeometry.constGet() );
QString error;
QgsGeometry errorLoc;
if ( !geos.isValid( &error, true, &errorLoc ) )
{
if ( errorLoc.isNull() )
{
emit errorFound( QgsGeometry::Error( error ) );
mErrorCount++;
}
else
{
const QgsPointXY point = errorLoc.asPoint();
emit errorFound( QgsGeometry::Error( error, point ) );
mErrorCount++;
}
}
break;
}
case QgsGeometry::ValidatorQgisInternal:
{
switch ( QgsWkbTypes::flatType( mGeometry.constGet()->wkbType() ) )
{
case QgsWkbTypes::Point:
case QgsWkbTypes::MultiPoint:
break;
case QgsWkbTypes::LineString:
validatePolyline( 0, qgsgeometry_cast< const QgsLineString * >( mGeometry.constGet() ) );
break;
case QgsWkbTypes::MultiLineString:
{
const QgsGeometryCollection *collection = qgsgeometry_cast< const QgsGeometryCollection * >( mGeometry.constGet() );
for ( int i = 0; !mStop && i < collection->numGeometries(); i++ )
validatePolyline( i, qgsgeometry_cast< const QgsLineString * >( collection->geometryN( i ) ) );
break;
}
case QgsWkbTypes::Polygon:
validatePolygon( 0, qgsgeometry_cast< const QgsPolygon * >( mGeometry.constGet() ) );
break;
case QgsWkbTypes::MultiPolygon:
{
const QgsGeometryCollection *collection = qgsgeometry_cast< const QgsGeometryCollection * >( mGeometry.constGet() );
for ( int i = 0; !mStop && i < collection->numGeometries(); i++ )
validatePolygon( i, qgsgeometry_cast< const QgsPolygon * >( collection->geometryN( i ) ) );
for ( int i = 0; !mStop && i < collection->numGeometries(); i++ )
{
const QgsPolygon *poly = qgsgeometry_cast< const QgsPolygon * >( collection->geometryN( i ) );
if ( !poly->exteriorRing() || poly->exteriorRing()->isEmpty() )
{
emit errorFound( QgsGeometry::Error( QObject::tr( "Polygon %1 has no rings" ).arg( i ) ) );
mErrorCount++;
continue;
}
for ( int j = i + 1; !mStop && j < collection->numGeometries(); j++ )
{
const QgsPolygon *poly2 = qgsgeometry_cast< const QgsPolygon * >( collection->geometryN( j ) );
if ( !poly2->exteriorRing() || poly2->exteriorRing()->isEmpty() )
continue;
if ( ringInRing( qgsgeometry_cast< const QgsLineString * >( poly->exteriorRing() ),
qgsgeometry_cast< const QgsLineString * >( poly2->exteriorRing() ) ) )
{
emit errorFound( QgsGeometry::Error( QObject::tr( "Polygon %1 lies inside polygon %2" ).arg( i ).arg( j ) ) );
mErrorCount++;
}
else if ( ringInRing( static_cast< const QgsLineString * >( poly2->exteriorRing() ),
static_cast< const QgsLineString * >( poly->exteriorRing() ) ) )
{
emit errorFound( QgsGeometry::Error( QObject::tr( "Polygon %1 lies inside polygon %2" ).arg( j ).arg( i ) ) );
mErrorCount++;
}
else
{
checkRingIntersections( i, 0, qgsgeometry_cast< const QgsLineString * >( poly->exteriorRing() ),
j, 0, qgsgeometry_cast< const QgsLineString * >( poly2->exteriorRing() ) );
}
}
}
break;
}
case QgsWkbTypes::Unknown:
{
emit errorFound( QgsGeometry::Error( QObject::tr( "Unknown geometry type %1" ).arg( mGeometry.wkbType() ) ) );
mErrorCount++;
break;
}
default:
break;
}
if ( mStop )
{
emit validationFinished( QObject::tr( "Geometry validation was aborted." ) );
}
else if ( mErrorCount > 0 )
{
emit validationFinished( QObject::tr( "Geometry has %1 errors." ).arg( mErrorCount ) );
}
else
{
emit validationFinished( QObject::tr( "Geometry is valid." ) );
}
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( double px, double py, QgsVector v, double qX, double qY )
{
const double l = v.length();
if ( qgsDoubleNear( l, 0 ) )
{
throw QgsException( QObject::tr( "invalid line" ) );
}
return ( v.x() * ( qY - py ) - v.y() * ( qX - px ) ) / l;
}
bool QgsGeometryValidator::intersectLines( double px, double py, QgsVector v, double qx, double qy, QgsVector w, double &sX, double &sY )
{
double d = v.y() * w.x() - v.x() * w.y();
if ( qgsDoubleNear( d, 0 ) )
return false;
double dx = qx - px;
double dy = qy - py;
double k = ( dy * w.x() - dx * w.y() ) / d;
sX = px + v.x() * k;
sY = py + v.y() * k;
return true;
}
bool QgsGeometryValidator::pointInRing( const QgsLineString *ring, double pX, double pY )
{
if ( !ring->boundingBox().contains( QgsPointXY( pX, pY ) ) )
return false;
bool inside = false;
int j = ring->numPoints() - 1;
for ( int i = 0; !mStop && i < ring->numPoints(); i++ )
{
const double xAti = ring->xAt( i );
const double yAti = ring->yAt( i );
const double xAtj = ring->xAt( j );
const double yAtj = ring->yAt( j );
if ( qgsDoubleNear( xAti, pX ) && qgsDoubleNear( yAti, pY ) )
return true;
if ( ( yAti < pY && yAtj >= pY ) ||
( yAtj < pY && yAti >= pY ) )
{
if ( xAti + ( pY - yAti ) / ( yAtj - yAti ) * ( xAtj - xAti ) <= pX )
inside = !inside;
}
j = i;
}
return inside;
}
bool QgsGeometryValidator::ringInRing( const QgsLineString *inside, const QgsLineString *outside )
{
if ( !outside->boundingBox().contains( inside->boundingBox() ) )
return false;
for ( int i = 0; !mStop && i < inside->numPoints(); i++ )
{
if ( !pointInRing( outside, inside->xAt( i ), inside->yAt( i ) ) )
return false;
}
return true;
}