bool QgsGeometryAnalyzer::centroids( QgsVectorLayer* layer, const QString& shapefileName,
bool onlySelectedFeatures, QProgressDialog* p )
{
if ( !layer )
{
QgsDebugMsg( "No layer passed to centroids" );
return false;
}
QgsVectorDataProvider* dp = layer->dataProvider();
if ( !dp )
{
QgsDebugMsg( "No data provider for layer passed to centroids" );
return false;
}
QgsWkbTypes::Type outputType = QgsWkbTypes::Point;
QgsCoordinateReferenceSystem crs = layer->crs();
QgsVectorFileWriter vWriter( shapefileName, dp->encoding(), layer->fields(), outputType, crs );
QgsFeature currentFeature;
//take only selection
if ( onlySelectedFeatures )
{
//use QgsVectorLayer::featureAtId
const QgsFeatureIds selection = layer->selectedFeaturesIds();
if ( p )
{
p->setMaximum( selection.size() );
}
int processedFeatures = 0;
QgsFeatureIds::const_iterator it = selection.constBegin();
for ( ; it != selection.constEnd(); ++it )
{
if ( p )
{
p->setValue( processedFeatures );
}
if ( p && p->wasCanceled() )
{
break;
}
if ( !layer->getFeatures( QgsFeatureRequest().setFilterFid( *it ) ).nextFeature( currentFeature ) )
{
continue;
}
centroidFeature( currentFeature, &vWriter );
++processedFeatures;
}
if ( p )
{
p->setValue( selection.size() );
}
}
//take all features
else
{
QgsFeatureIterator fit = layer->getFeatures( QgsFeatureRequest().setSubsetOfAttributes( QgsAttributeList() ) );
int featureCount = layer->featureCount();
if ( p )
{
p->setMaximum( featureCount );
}
int processedFeatures = 0;
while ( fit.nextFeature( currentFeature ) )
{
if ( p )
{
p->setValue( processedFeatures );
}
if ( p && p->wasCanceled() )
{
break;
}
centroidFeature( currentFeature, &vWriter );
++processedFeatures;
}
if ( p )
{
p->setValue( featureCount );
}
}
return true;
}
bool QgsGeometryAnalyzer::centroids( QgsVectorLayer* layer, const QString& shapefileName,
bool onlySelectedFeatures, QProgressDialog* p )
{
if ( !layer )
{
return false;
}
QgsVectorDataProvider* dp = layer->dataProvider();
if ( !dp )
{
return false;
}
QGis::WkbType outputType = QGis::WKBPoint;
const QgsCoordinateReferenceSystem crs = layer->crs();
QgsVectorFileWriter vWriter( shapefileName, dp->encoding(), dp->fields(), outputType, &crs );
QgsFeature currentFeature;
//take only selection
if ( onlySelectedFeatures )
{
//use QgsVectorLayer::featureAtId
const QgsFeatureIds selection = layer->selectedFeaturesIds();
if ( p )
{
p->setMaximum( selection.size() );
}
int processedFeatures = 0;
QgsFeatureIds::const_iterator it = selection.constBegin();
for ( ; it != selection.constEnd(); ++it )
{
if ( p )
{
p->setValue( processedFeatures );
}
if ( p && p->wasCanceled() )
{
break;
}
if ( !layer->featureAtId( *it, currentFeature, true, true ) )
{
continue;
}
centroidFeature( currentFeature, &vWriter );
++processedFeatures;
}
if ( p )
{
p->setValue( selection.size() );
}
}
//take all features
else
{
layer->select( layer->pendingAllAttributesList(), QgsRectangle(), true, false );
int featureCount = layer->featureCount();
if ( p )
{
p->setMaximum( featureCount );
}
int processedFeatures = 0;
while ( layer->nextFeature( currentFeature ) )
{
if ( p )
{
p->setValue( processedFeatures );
}
if ( p && p->wasCanceled() )
{
break;
}
centroidFeature( currentFeature, &vWriter );
++processedFeatures;
}
if ( p )
{
p->setValue( featureCount );
}
}
return true;
}
