C++ (Cpp) QgsVectorLayer::updateExtents Examples

Example #1

File: shortestpathwidget.cpp Project: Br1ndavoine/QGIS

void RgShortestPathWidget::exportPath()
{
  RgExportDlg dlg( this );
  if ( !dlg.exec() )
    return;

  QgsVectorLayer *vl = dlg.mapLayer();
  if ( vl == NULL )
    return;

  QgsPoint p1, p2;
  QgsGraph *path = getPath( p1, p2 );
  if ( path == NULL )
    return;

  QgsCoordinateTransform ct( mPlugin->iface()->mapCanvas()->mapSettings().destinationCrs(),
                             vl->crs() );

  int startVertexIdx = path->findVertex( p1 );
  int stopVertexIdx  = path->findVertex( p2 );

  double time = 0.0;
  double cost = 0.0;

  Unit timeUnit = Unit::byName( mPlugin->timeUnitName() );
  Unit distanceUnit = Unit::byName( mPlugin->distanceUnitName() );

  QgsPolyline p;
  while ( startVertexIdx != stopVertexIdx )
  {
    if ( stopVertexIdx < 0 )
      break;

    QgsGraphArcIdList l = path->vertex( stopVertexIdx ).inArc();
    if ( l.empty() )
      break;
    const QgsGraphArc& e = path->arc( l.front() );

    cost += e.property( 0 ).toDouble();
    time += e.property( 1 ).toDouble();

    p.push_front( ct.transform( path->vertex( e.inVertex() ).point() ) );
    stopVertexIdx = e.outVertex();
  }
  p.push_front( ct.transform( p1 ) );

  QgsFeature f;
  f.initAttributes( vl->pendingFields().count() );
  f.setGeometry( QgsGeometry::fromPolyline( p ) );
  f.setAttribute( 0, cost / distanceUnit.multipler() );
  f.setAttribute( 1, time / timeUnit.multipler() );
  QgsFeatureList features;
  features << f;
  vl->dataProvider()->addFeatures( features );
  vl->updateExtents();

  mPlugin->iface()->mapCanvas()->update();
  delete path;
}

Example #2

File: shortestpathwidget.cpp Project: afrigeo/Quantum-GIS

void RgShortestPathWidget::exportPath()
{
  RgExportDlg dlg( this );
  if ( !dlg.exec() )
    return;

  QgsVectorLayer *vl = dlg.mapLayer();
  if ( vl == NULL )
    return;

  QgsPoint p1, p2;
  QgsGraph *path = getPath( p1, p2 );
  if ( path == NULL )
    return;

  QgsCoordinateTransform ct( mPlugin->iface()->mapCanvas()->mapRenderer()->destinationCrs(),
                             vl->crs() );

  int startVertexIdx = path->findVertex( p1 );
  int stopVertexIdx  = path->findVertex( p2 );

  QgsPolyline p;
  while ( startVertexIdx != stopVertexIdx )
  {
    QgsGraphArcIdList l = path->vertex( stopVertexIdx ).inArc();
    if ( l.empty() )
      break;
    const QgsGraphArc& e = path->arc( l.front() );
    p.push_front( ct.transform( path->vertex( e.inVertex() ).point() ) );
    stopVertexIdx = e.outVertex();
  }
  p.push_front( ct.transform( p1 ) );

  vl->startEditing();
  QgsFeature f;
  f.setGeometry( QgsGeometry::fromPolyline( p ) );
  vl->addFeature( f );
  vl->updateExtents();

  mPlugin->iface()->mapCanvas()->update();
  delete path;
}