[Geometry checker] Add line intersection check

Author: manisandro

src/plugins/geometry_checker/CMakeLists.txt

@@ -15,6 +15,7 @@ SET (geometrychecker_SRCS
     checks/qgsgeometrycheck.cpp
     checks/qgsgeometrygapcheck.cpp
     checks/qgsgeometryholecheck.cpp
+    checks/qgsgeometrylineintersectioncheck.cpp
     checks/qgsgeometrymultipartcheck.cpp
     checks/qgsgeometrycontainedcheck.cpp
     checks/qgsgeometryoverlapcheck.cpp
@@ -53,6 +54,7 @@ SET (geometrychecker_MOC_HDRS
     checks/qgsgeometryduplicatenodescheck.h
     checks/qgsgeometrygapcheck.h
     checks/qgsgeometryholecheck.h
+    checks/qgsgeometrylineintersectioncheck.h
     checks/qgsgeometrymultipartcheck.h
     checks/qgsgeometrycontainedcheck.h
     checks/qgsgeometryoverlapcheck.h

src/plugins/geometry_checker/checks/qgsgeometrylineintersectioncheck.cpp

@@ -0,0 +1,79 @@
+/***************************************************************************
+    qgsgeometrylineintersectioncheck.cpp
+    ---------------------
+    begin                : June 2017
+    copyright            : (C) 2017 by Sandro Mani / Sourcepole AG
+    email                : smani at sourcepole dot 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.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#include "qgsgeometrylineintersectioncheck.h"
+#include "qgslinestring.h"
+
+void QgsGeometryLineIntersectionCheck::collectErrors( QList<QgsGeometryCheckError *> &errors, QStringList &/*messages*/, QAtomicInt *progressCounter, const QMap<QString, QgsFeatureIds> &ids ) const
+{
+  QMap<QString, QgsFeatureIds> featureIds = ids.isEmpty() ? allLayerFeatureIds() : ids;
+  QgsGeometryCheckerUtils::LayerFeatures layerFeatures( mContext->featurePools, featureIds, mCompatibleGeometryTypes, progressCounter, true );
+  for ( const QgsGeometryCheckerUtils::LayerFeature &layerFeature : layerFeatures )
+  {
+    const QgsAbstractGeometry *geom = layerFeature.geometry();
+    for ( int iPart = 0, nParts = geom->partCount(); iPart < nParts; ++iPart )
+    {
+      const QgsLineString *line = dynamic_cast<const QgsLineString *>( QgsGeometryCheckerUtils::getGeomPart( geom, iPart ) );
+      if ( !line )
+      {
+        // Should not happen
+        continue;
+      }
+
+      // Check whether the line intersects with any other lines
+      QgsGeometryCheckerUtils::LayerFeatures checkFeatures( mContext->featurePools, featureIds.keys(), line->boundingBox(), {QgsWkbTypes::LineGeometry} );
+      for ( const QgsGeometryCheckerUtils::LayerFeature &checkFeature : checkFeatures )
+      {
+        if ( checkFeature.feature().id() == layerFeature.feature().id() )
+        {
+          // Skip current feature
+          continue;
+        }
+        const QgsAbstractGeometry *testGeom = checkFeature.geometry();
+        for ( int jPart = 0, mParts = testGeom->partCount(); jPart < mParts; ++jPart )
+        {
+          const QgsLineString *testLine = dynamic_cast<const QgsLineString *>( QgsGeometryCheckerUtils::getGeomPart( testGeom, jPart ) );
+          if ( !testLine )
+          {
+            continue;
+          }
+          QgsPoint inter;
+          if ( QgsGeometryCheckerUtils::linesIntersect( line, testLine, mContext->tolerance, inter ) )
+          {
+            errors.append( new QgsGeometryCheckError( this, layerFeature, inter ) );
+          }
+        }
+      }
+    }
+  }
+}
+
+void QgsGeometryLineIntersectionCheck::fixError( QgsGeometryCheckError *error, int method, const QMap<QString, int> & /*mergeAttributeIndices*/, Changes & /*changes*/ ) const
+{
+  if ( method == NoChange )
+  {
+    error->setFixed( method );
+  }
+  else
+  {
+    error->setFixFailed( tr( "Unknown method" ) );
+  }
+}
+
+QStringList QgsGeometryLineIntersectionCheck::getResolutionMethods() const
+{
+  static QStringList methods = QStringList() << tr( "No action" );
+  return methods;
+}

src/plugins/geometry_checker/checks/qgsgeometrylineintersectioncheck.h

@@ -0,0 +1,38 @@
+/***************************************************************************
+    qgsgeometrylineintersectioncheck.h
+    ---------------------
+    begin                : June 2017
+    copyright            : (C) 2017 by Sandro Mani / Sourcepole AG
+    email                : smani at sourcepole dot 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 QGSGEOMETRYLINEINTERSECTIONCHECK_H
+#define QGSGEOMETRYLINEINTERSECTIONCHECK_H
+
+#include "qgsgeometrycheck.h"
+
+class QgsGeometryLineIntersectionCheck : public QgsGeometryCheck
+{
+    Q_OBJECT
+
+  public:
+    QgsGeometryLineIntersectionCheck( QgsGeometryCheckerContext *context )
+      : QgsGeometryCheck( FeatureNodeCheck, {QgsWkbTypes::LineGeometry}, context )
+    {}
+    void collectErrors( QList<QgsGeometryCheckError *> &errors, QStringList &messages, QAtomicInt *progressCounter = nullptr, const QMap<QString, QgsFeatureIds> &ids = QMap<QString, QgsFeatureIds>() ) const override;
+    void fixError( QgsGeometryCheckError *error, int method, const QMap<QString, int> &mergeAttributeIndices, Changes &changes ) const override;
+    QStringList getResolutionMethods() const override;
+    QString errorDescription() const override { return tr( "Intersection" ); }
+    QString errorName() const override { return QStringLiteral( "QgsGeometryLineIntersectionCheck" ); }
+  private:
+    enum ResolutionMethod { NoChange };
+};
+
+#endif // QGSGEOMETRYLINEINTERSECTIONCHECK_H

src/plugins/geometry_checker/qgsgeometrycheckfactory.cpp

@@ -25,6 +25,7 @@
 #include "checks/qgsgeometryduplicatenodescheck.h"
 #include "checks/qgsgeometrygapcheck.h"
 #include "checks/qgsgeometryholecheck.h"
+#include "checks/qgsgeometrylineintersectioncheck.h"
 #include "checks/qgsgeometrymultipartcheck.h"
 #include "checks/qgsgeometryoverlapcheck.h"
 #include "checks/qgsgeometrypointcoveredbylinecheck.h"
@@ -299,6 +300,35 @@ REGISTER_QGS_GEOMETRY_CHECK_FACTORY( QgsGeometryCheckFactoryT<QgsGeometryHoleChe
 
 ///////////////////////////////////////////////////////////////////////////////
 
+template<> void QgsGeometryCheckFactoryT<QgsGeometryLineIntersectionCheck>::restorePrevious( Ui::QgsGeometryCheckerSetupTab &ui ) const
+{
+  ui.checkLineIntersection->setChecked( QgsSettings().value( sSettingsGroup + "checkLineIntersection" ).toBool() );
+}
+
+template<> bool QgsGeometryCheckFactoryT<QgsGeometryLineIntersectionCheck>::checkApplicability( Ui::QgsGeometryCheckerSetupTab &ui, int /*nPoint*/, int nLineString, int /*nPolygon*/ ) const
+{
+  ui.checkLineIntersection->setEnabled( nLineString > 0 );
+  return ui.checkLineIntersection->isEnabled();
+}
+
+template<> QgsGeometryCheck *QgsGeometryCheckFactoryT<QgsGeometryLineIntersectionCheck>::createInstance( QgsGeometryCheckerContext *context, const Ui::QgsGeometryCheckerSetupTab &ui ) const
+{
+  QgsSettings().setValue( sSettingsGroup + "checkLineIntersection", ui.checkLineIntersection->isChecked() );
+  if ( ui.checkLineIntersection->isEnabled() && ui.checkLineIntersection->isChecked() )
+  {
+    return new QgsGeometryLineIntersectionCheck( context );
+  }
+  else
+  {
+    return nullptr;
+  }
+}
+
+REGISTER_QGS_GEOMETRY_CHECK_FACTORY( QgsGeometryCheckFactoryT<QgsGeometryLineIntersectionCheck> )
+
+///////////////////////////////////////////////////////////////////////////////
+
+
 template<> void QgsGeometryCheckFactoryT<QgsGeometryMultipartCheck>::restorePrevious( Ui::QgsGeometryCheckerSetupTab &ui ) const
 {
   ui.checkBoxMultipart->setChecked( QgsSettings().value( sSettingsGroup + "checkMultipart" ).toBool() );

src/plugins/geometry_checker/ui/qgsgeometrycheckersetuptab.ui

@@ -43,7 +43,7 @@
         <x>0</x>
         <y>0</y>
         <width>626</width>
-        <height>895</height>
+        <height>918</height>
        </rect>
       </property>
       <layout class="QGridLayout" name="gridLayout_4">
@@ -511,6 +511,13 @@
                </property>
               </widget>
              </item>
+             <item row="5" column="0">
+              <widget class="QCheckBox" name="checkLineIntersection">
+               <property name="text">
+                <string>Lines must not intersect</string>
+               </property>
+              </widget>
+             </item>
              <item row="0" column="0">
               <widget class="QCheckBox" name="checkBoxDuplicates">
                <property name="text">
@@ -535,7 +542,7 @@
                </property>
               </widget>
              </item>
-             <item row="5" column="0" colspan="2">
+             <item row="8" column="0" colspan="2">
               <widget class="QLabel" name="label">
                <property name="text">
                 <string>&lt;i&gt;Note: Topology checks are performed in the current map CRS.&lt;/i&gt;</string>
@@ -552,7 +559,7 @@
                </property>
               </widget>
              </item>
-             <item row="4" column="0" colspan="2">
+             <item row="4" column="0">
               <widget class="QCheckBox" name="checkPointCoveredByLine">
                <property name="text">
                 <string>Points must be covered by lines</string>

src/plugins/geometry_checker/utils/qgsgeometrycheckerutils.cpp

@@ -222,6 +222,25 @@ namespace QgsGeometryCheckerUtils
     return false;
   }
 
+  bool linesIntersect( const QgsLineString *line1, const QgsLineString *line2, double tol, QgsPoint &inter )
+  {
+    for ( int i = 0, n = line1->vertexCount() - 1; i < n; ++i )
+    {
+      for ( int j = 0, m = line2->vertexCount() - 1; j < m; ++j )
+      {
+        QgsPoint p1 = line1->vertexAt( QgsVertexId( 0, 0, i ) );
+        QgsPoint p2 = line1->vertexAt( QgsVertexId( 0, 0, i + 1 ) );
+        QgsPoint q1 = line1->vertexAt( QgsVertexId( 0, 0, j ) );
+        QgsPoint q2 = line1->vertexAt( QgsVertexId( 0, 0, j + 1 ) );
+        if ( QgsGeometryUtils::segmentIntersection( p1, p2, q1, q2, inter, tol ) )
+        {
+          return true;
+        }
+      }
+    }
+    return false;
+  }
+
   double sharedEdgeLength( const QgsAbstractGeometry *geom1, const QgsAbstractGeometry *geom2, double tol )
   {
     double len = 0;

src/plugins/geometry_checker/utils/qgsgeometrycheckerutils.h

@@ -128,6 +128,8 @@ namespace QgsGeometryCheckerUtils
 
   bool pointOnLine( const QgsPoint &p, const QgsLineString *line, double tol, bool excludeExtremities = false );
 
+  bool linesIntersect( const QgsLineString *line1, const QgsLineString *line2, double tol, QgsPoint &inter );
+
   double sharedEdgeLength( const QgsAbstractGeometry *geom1, const QgsAbstractGeometry *geom2, double tol );
 
   /**