C++ QgsVectorLayer::addTopologicalPoints方法代码示例

void QgsMapToolAddFeature::digitized( QgsFeature &f )
{
  QgsVectorLayer *vlayer = currentVectorLayer();
  bool res = addFeature( vlayer, &f, false );

  if ( res && ( mode() == CaptureLine || mode() == CapturePolygon ) )
  {
    //add points to other features to keep topology up-to-date
    bool topologicalEditing = QgsProject::instance()->topologicalEditing();

    //use always topological editing for avoidIntersection.
    //Otherwise, no way to guarantee the geometries don't have a small gap in between.
    QList<QgsVectorLayer *> intersectionLayers = QgsProject::instance()->avoidIntersectionsLayers();
    bool avoidIntersection = !intersectionLayers.isEmpty();
    if ( avoidIntersection ) //try to add topological points also to background layers
    {
      const auto constIntersectionLayers = intersectionLayers;
      for ( QgsVectorLayer *vl : constIntersectionLayers )
      {
        //can only add topological points if background layer is editable...
        if ( vl->geometryType() == QgsWkbTypes::PolygonGeometry && vl->isEditable() )
        {
          vl->addTopologicalPoints( f.geometry() );
        }
      }
    }
    else if ( topologicalEditing )
    {
      vlayer->addTopologicalPoints( f.geometry() );
    }
  }
}

int QgsMapToolEdit::addTopologicalPoints( const QList<QgsPoint>& geom )
{
  if ( !mCanvas )
  {
    return 1;
  }

  //find out current vector layer
  QgsVectorLayer *vlayer = currentVectorLayer();

  if ( !vlayer )
  {
    return 2;
  }

  QList<QgsPoint>::const_iterator list_it = geom.constBegin();
  for ( ; list_it != geom.constEnd(); ++list_it )
  {
    vlayer->addTopologicalPoints( *list_it );
  }
  return 0;
}

//.........这里部分代码省略.........
      //polygons: bail out if there are not at least two vertices
      if ( mode() == CapturePolygon && size() < 3 )
      {
        stopCapturing();
        return;
      }

      //create QgsFeature with wkb representation
      QgsFeature* f = new QgsFeature( 0, "WKBLineString" );

      QgsGeometry *g;

      if ( mode() == CaptureLine )
      {
        if ( layerWKBType == QGis::WKBLineString || layerWKBType == QGis::WKBLineString25D )
        {
          g = QgsGeometry::fromPolyline( points().toVector() );
        }
        else if ( layerWKBType == QGis::WKBMultiLineString || layerWKBType == QGis::WKBMultiLineString25D )
        {
          g = QgsGeometry::fromMultiPolyline( QgsMultiPolyline() << points().toVector() );
        }
        else
        {
          QMessageBox::critical( 0, tr( "Error" ), tr( "Cannot add feature. Unknown WKB type" ) );
          stopCapturing();
          return; //unknown wkbtype
        }

        f->setGeometry( g );
      }
      else // polygon
      {
        if ( layerWKBType == QGis::WKBPolygon ||  layerWKBType == QGis::WKBPolygon25D )
        {
          g = QgsGeometry::fromPolygon( QgsPolygon() << points().toVector() );
        }
        else if ( layerWKBType == QGis::WKBMultiPolygon ||  layerWKBType == QGis::WKBMultiPolygon25D )
        {
          g = QgsGeometry::fromMultiPolygon( QgsMultiPolygon() << ( QgsPolygon() << points().toVector() ) );
        }
        else
        {
          QMessageBox::critical( 0, tr( "Error" ), tr( "Cannot add feature. Unknown WKB type" ) );
          stopCapturing();
          return; //unknown wkbtype
        }

        if ( !g )
        {
          stopCapturing();
          delete f;
          return; // invalid geometry; one possibility is from duplicate points
        }
        f->setGeometry( g );

        int avoidIntersectionsReturn = f->geometry()->avoidIntersections();
        if ( avoidIntersectionsReturn == 1 )
        {
          //not a polygon type. Impossible to get there
        }
#if 0
        else if ( avoidIntersectionsReturn == 2 ) //MH120131: disable this error message until there is a better way to cope with the single type / multi type problem
        {
          //bail out...
          QMessageBox::critical( 0, tr( "Error" ), tr( "The feature could not be added because removing the polygon intersections would change the geometry type" ) );
          delete f;
          stopCapturing();
          return;
        }
#endif
        else if ( avoidIntersectionsReturn == 3 )
        {
          QMessageBox::critical( 0, tr( "Error" ), tr( "An error was reported during intersection removal" ) );
        }
      }

      vlayer->beginEditCommand( tr( "Feature added" ) );

      if ( addFeature( vlayer, f ) )
      {
        //add points to other features to keep topology up-to-date
        int topologicalEditing = QgsProject::instance()->readNumEntry( "Digitizing", "/TopologicalEditing", 0 );
        if ( topologicalEditing )
        {
          vlayer->addTopologicalPoints( f->geometry() );
        }

        vlayer->endEditCommand();
      }
      else
      {
        delete f;
        vlayer->destroyEditCommand();
      }

      stopCapturing();
    }
  }
}

//.........这里部分代码省略.........
      bool hasCurvedSegments = captureCurve()->hasCurvedSegments();
      bool providerSupportsCurvedSegments = vlayer->dataProvider()->capabilities() & QgsVectorDataProvider::CircularGeometries;

      QgsCurveV2* curveToAdd = 0;
      if ( hasCurvedSegments && providerSupportsCurvedSegments )
      {
        curveToAdd = captureCurve()->clone();
      }
      else
      {
        curveToAdd = captureCurve()->curveToLine();
      }

      if ( mode() == CaptureLine )
      {
        f->setGeometry( new QgsGeometry( curveToAdd ) );
      }
      else
      {
        QgsCurvePolygonV2* poly = 0;
        if ( hasCurvedSegments && providerSupportsCurvedSegments )
        {
          poly = new QgsCurvePolygonV2();
        }
        else
        {
          poly = new QgsPolygonV2();
        }
        poly->setExteriorRing( curveToAdd );
        f->setGeometry( new QgsGeometry( poly ) );

        int avoidIntersectionsReturn = f->geometry()->avoidIntersections();
        if ( avoidIntersectionsReturn == 1 )
        {
          //not a polygon type. Impossible to get there
        }
#if 0
        else if ( avoidIntersectionsReturn == 2 ) //MH120131: disable this error message until there is a better way to cope with the single type / multi type problem
        {
          //bail out...
          emit messageEmitted( tr( "The feature could not be added because removing the polygon intersections would change the geometry type" ), QgsMessageBar::CRITICAL );
          stopCapturing();
          return;
        }
#endif
        else if ( avoidIntersectionsReturn == 3 )
        {
          emit messageEmitted( tr( "An error was reported during intersection removal" ), QgsMessageBar::CRITICAL );
        }

        if ( !f->constGeometry()->asWkb() ) //avoid intersection might have removed the whole geometry
        {
          QString reason;
          if ( avoidIntersectionsReturn != 2 )
          {
            reason = tr( "The feature cannot be added because it's geometry is empty" );
          }
          else
          {
            reason = tr( "The feature cannot be added because it's geometry collapsed due to intersection avoidance" );
          }
          emit messageEmitted( reason, QgsMessageBar::CRITICAL );
          stopCapturing();
          return;
        }
      }

      if ( addFeature( vlayer, f.data(), false ) )
      {
        //add points to other features to keep topology up-to-date
        int topologicalEditing = QgsProject::instance()->readNumEntry( "Digitizing", "/TopologicalEditing", 0 );

        //use always topological editing for avoidIntersection.
        //Otherwise, no way to guarantee the geometries don't have a small gap in between.
        QStringList intersectionLayers = QgsProject::instance()->readListEntry( "Digitizing", "/AvoidIntersectionsList" );
        bool avoidIntersection = !intersectionLayers.isEmpty();
        if ( avoidIntersection ) //try to add topological points also to background layers
        {
          QStringList::const_iterator lIt = intersectionLayers.constBegin();
          for ( ; lIt != intersectionLayers.constEnd(); ++lIt )
          {
            QgsMapLayer* ml = QgsMapLayerRegistry::instance()->mapLayer( *lIt );
            QgsVectorLayer* vl = qobject_cast<QgsVectorLayer*>( ml );
            //can only add topological points if background layer is editable...
            if ( vl && vl->geometryType() == QGis::Polygon && vl->isEditable() )
            {
              vl->addTopologicalPoints( f->constGeometry() );
            }
          }
        }
        else if ( topologicalEditing )
        {
          vlayer->addTopologicalPoints( f->constGeometry() );
        }
      }

      stopCapturing();
    }
  }
}