[FEATURE] Allow overide of geometry type in vector save as dialog

Also allows forcing output file to be multi type, or include z
dimension.

This makes it possible to do things like save a geometryless
table WITH a geometry type, so that geometries can then be
manually added to rows. Previously this was only possible to do in
QGIS by resorting to dummy joins or other hacks.

python/core/qgsvectorfilewriter.sip

@@ -121,7 +121,10 @@ class QgsVectorFileWriter
     @param newFilename QString pointer which will contain the new file name created (in case it is different to fileName).
     @param symbologyExport symbology to export
     @param symbologyScale scale of symbology
-    @param filterExtent if not a null pointer, only features intersecting the extent will be saved
+    @param filterExtent if not a null pointer, only features intersecting the extent will be saved (added in QGIS 2.4)
+    allows for conversion of geometryless tables to null geometries, etc (added in QGIS 2.14)
+    @param forceMulti set to true to force creation of multi* geometries (added in QGIS 2.14)
+    @param includeZ set to true to include z dimension in output. This option is only valid if overrideGeometryType is set. (added in QGIS 2.14)
     */
     static WriterError writeAsVectorFormat( QgsVectorLayer* layer,
                                             const QString& fileName,
@@ -136,10 +139,33 @@ class QgsVectorFileWriter
                                             QString *newFilename = 0,
                                             SymbologyExport symbologyExport = NoSymbology,
                                             double symbologyScale = 1.0,
-                                            const QgsRectangle* filterExtent = 0 // added in 2.4
+                                            const QgsRectangle* filterExtent = 0,
+                                            QgsWKBTypes::Type overrideGeometryType = QgsWKBTypes::Unknown,
+                                            bool forceMulti = false,
+                                            bool includeZ = false
                                           );
 
-    //! @note added in v2.2
+    /** Writes a layer out to a vector file.
+     * @param layer layer to write
+     * @param fileName file name to write to
+     * @param fileEncoding encoding to use
+     * @param ct
+     * @param driverName OGR driver to use
+     * @param onlySelected write only selected features of layer
+     * @param errorMessage pointer to buffer fo error message
+     * @param datasourceOptions list of OGR data source creation options
+     * @param layerOptions list of OGR layer creation options
+     * @param skipAttributeCreation only write geometries
+     * @param newFilename QString pointer which will contain the new file name created (in case it is different to fileName).
+     * @param symbologyExport symbology to export
+     * @param symbologyScale scale of symbology
+     * @param filterExtent if not a null pointer, only features intersecting the extent will be saved (added in QGIS 2.4)
+     * @param overrideGeometryType set to a valid geometry type to override the default geometry type for the layer. This parameter
+     * allows for conversion of geometryless tables to null geometries, etc (added in QGIS 2.14)
+     * @param forceMulti set to true to force creation of multi* geometries (added in QGIS 2.14)
+     * @param includeZ set to true to include z dimension in output. This option is only valid if overrideGeometryType is set. (added in QGIS 2.14)
+     * @note added in v2.2
+     */
     static WriterError writeAsVectorFormat( QgsVectorLayer* layer,
                                             const QString& fileName,
                                             const QString& fileEncoding,
@@ -153,7 +179,10 @@ class QgsVectorFileWriter
                                             QString *newFilename = 0,
                                             SymbologyExport symbologyExport = NoSymbology,
                                             double symbologyScale = 1.0,
-                                            const QgsRectangle* filterExtent = 0 // added in 2.4
+                                            const QgsRectangle* filterExtent = 0,
+                                            QgsWKBTypes::Type overrideGeometryType = QgsWKBTypes::Unknown,
+                                            bool forceMulti = false,
+                                            bool includeZ = false
                                           );
 
     /** Create shapefile and initialize it */

src/app/ogr/qgsvectorlayersaveasdialog.cpp

@@ -67,6 +67,15 @@ void QgsVectorLayerSaveAsDialog::setup()
   mFormatComboBox->setCurrentIndex( mFormatComboBox->findData( format ) );
   mFormatComboBox->blockSignals( false );
 
+  //add geometry types to combobox
+  mGeometryTypeComboBox->addItem( tr( "Automatic" ), -1 );
+  mGeometryTypeComboBox->addItem( QgsWKBTypes::displayString( QgsWKBTypes::Point ), QgsWKBTypes::Point );
+  mGeometryTypeComboBox->addItem( QgsWKBTypes::displayString( QgsWKBTypes::LineString ), QgsWKBTypes::LineString );
+  mGeometryTypeComboBox->addItem( QgsWKBTypes::displayString( QgsWKBTypes::Polygon ), QgsWKBTypes::Polygon );
+  mGeometryTypeComboBox->addItem( QgsWKBTypes::displayString( QgsWKBTypes::GeometryCollection ), QgsWKBTypes::GeometryCollection );
+  mGeometryTypeComboBox->addItem( tr( "No geometry" ), QgsWKBTypes::NoGeometry );
+  mGeometryTypeComboBox->setCurrentIndex( mGeometryTypeComboBox->findData( -1 ) );
+
   mEncodingComboBox->addItems( QgsVectorDataProvider::availableEncodings() );
 
   QString enc = settings.value( "/UI/encoding", "System" ).toString();
@@ -458,6 +467,44 @@ bool QgsVectorLayerSaveAsDialog::onlySelected() const
   return mSelectedOnly->isChecked();
 }
 
+QgsWKBTypes::Type QgsVectorLayerSaveAsDialog::geometryType() const
+{
+  int currentIndexData = mGeometryTypeComboBox->itemData( mGeometryTypeComboBox->currentIndex() ).toInt();
+  if ( currentIndexData == -1 )
+  {
+    //automatic
+    return QgsWKBTypes::Unknown;
+  }
+
+  return ( QgsWKBTypes::Type )currentIndexData;
+}
+
+bool QgsVectorLayerSaveAsDialog::automaticGeometryType() const
+{
+  int currentIndexData = mGeometryTypeComboBox->itemData( mGeometryTypeComboBox->currentIndex() ).toInt();
+  return currentIndexData == -1;
+}
+
+bool QgsVectorLayerSaveAsDialog::forceMulti() const
+{
+  return mForceMultiCheckBox->isChecked();
+}
+
+void QgsVectorLayerSaveAsDialog::setForceMulti( bool checked )
+{
+  mForceMultiCheckBox->setChecked( checked );
+}
+
+bool QgsVectorLayerSaveAsDialog::includeZ() const
+{
+  return mIncludeZCheckBox->isChecked();
+}
+
+void QgsVectorLayerSaveAsDialog::setIncludeZ( bool checked )
+{
+  mIncludeZCheckBox->setChecked( checked );
+}
+
 void QgsVectorLayerSaveAsDialog::on_mSymbologyExportComboBox_currentIndexChanged( const QString& text )
 {
   bool scaleEnabled = true;
@@ -468,3 +515,11 @@ void QgsVectorLayerSaveAsDialog::on_mSymbologyExportComboBox_currentIndexChanged
   mScaleSpinBox->setEnabled( scaleEnabled );
   mScaleLabel->setEnabled( scaleEnabled );
 }
+
+void QgsVectorLayerSaveAsDialog::on_mGeometryTypeComboBox_currentIndexChanged( int index )
+{
+  int currentIndexData = mGeometryTypeComboBox->itemData( index ).toInt();
+
+  mForceMultiCheckBox->setEnabled( currentIndexData != -1 );
+  mIncludeZCheckBox->setEnabled( currentIndexData != -1 );
+}

src/app/ogr/qgsvectorlayersaveasdialog.h

@@ -65,13 +65,44 @@ class QgsVectorLayerSaveAsDialog : public QDialog, private Ui::QgsVectorLayerSav
 
     bool onlySelected() const;
 
+    /** Returns the selected flat geometry type for the export.
+     * @see automaticGeometryType()
+     * @see forceMulti()
+     * @see includeZ()
+     */
+    QgsWKBTypes::Type geometryType() const;
+
+    /** Returns true if geometry type is set to automatic.
+     * @see geometryType()
+     */
+    bool automaticGeometryType() const;
+
+    /** Returns true if force multi geometry type is checked.
+     * @see includeZ()
+     */
+    bool forceMulti() const;
+
+    /** Sets whether the force multi geometry checkbox should be checked.
+     */
+    void setForceMulti( bool checked );
+
+    /** Returns true if include z dimension is checked.
+     * @see forceMulti()
+     */
+    bool includeZ() const;
+
+    /** Sets whether the include z dimension checkbox should be checked.
+     */
+    void setIncludeZ( bool checked );
+
   private slots:
     void on_mFormatComboBox_currentIndexChanged( int idx );
     void on_leFilename_textChanged( const QString& text );
     void on_browseFilename_clicked();
     void on_mCrsSelector_crsChanged( const QgsCoordinateReferenceSystem& crs );
     void on_buttonBox_helpRequested() { QgsContextHelp::run( metaObject()->className() ); }
     void on_mSymbologyExportComboBox_currentIndexChanged( const QString& text );
+    void on_mGeometryTypeComboBox_currentIndexChanged( int index );
     void accept() override;
 
   private:

src/app/qgisapp.cpp

@@ -5476,13 +5476,16 @@ void QgisApp::saveAsVectorFileGeneral( QgsVectorLayer* vlayer, bool symbologyOpt
   QgsVectorLayerSaveAsDialog *dialog = new QgsVectorLayerSaveAsDialog( vlayer->crs().srsid(), vlayer->extent(), vlayer->selectedFeatureCount() != 0, options, this );
 
   dialog->setCanvasExtent( mMapCanvas->mapSettings().visibleExtent(), mMapCanvas->mapSettings().destinationCrs() );
+  dialog->setIncludeZ( QgsWKBTypes::hasZ( QGis::fromOldWkbType( vlayer->wkbType() ) ) );
 
   if ( dialog->exec() == QDialog::Accepted )
   {
     QString encoding = dialog->encoding();
     QString vectorFilename = dialog->filename();
     QString format = dialog->format();
     QStringList datasourceOptions = dialog->datasourceOptions();
+    bool autoGeometryType = dialog->automaticGeometryType();
+    QgsWKBTypes::Type forcedGeometryType = dialog->geometryType();
 
     QgsCoordinateTransform* ct = 0;
     destCRS = QgsCoordinateReferenceSystem( dialog->crs(), QgsCoordinateReferenceSystem::InternalCrsId );
@@ -5529,7 +5532,11 @@ void QgisApp::saveAsVectorFileGeneral( QgsVectorLayer* vlayer, bool symbologyOpt
               &newFilename,
               ( QgsVectorFileWriter::SymbologyExport )( dialog->symbologyExport() ),
               dialog->scaleDenominator(),
-              dialog->hasFilterExtent() ? &filterExtent : 0 );
+              dialog->hasFilterExtent() ? &filterExtent : 0,
+              autoGeometryType ? QgsWKBTypes::Unknown : forcedGeometryType,
+              dialog->forceMulti(),
+              dialog->includeZ()
+            );
 
     delete ct;
 

src/core/qgsvectorfilewriter.cpp

@@ -1725,7 +1725,8 @@ OGRFeatureH QgsVectorFileWriter::createFeature( QgsFeature& feature )
     QgsGeometry *geom = feature.geometry();
 
     // turn single geoemetry to multi geometry if needed
-    if ( geom && geom->wkbType() != mWkbType && geom->wkbType() == QGis::singleType( mWkbType ) )
+    if ( geom && geom->wkbType() != mWkbType &&
+         QgsWKBTypes::flatType( geom->geometry()->wkbType() ) == QgsWKBTypes::flatType( QgsWKBTypes::singleType( QGis::fromOldWkbType( mWkbType ) ) ) )
     {
       geom->convertToMultiType();
     }
@@ -1738,6 +1739,10 @@ OGRFeatureH QgsVectorFileWriter::createFeature( QgsFeature& feature )
       // we must force the use of 25D.
       if ( mWkbType >= QGis::WKBPoint25D && mWkbType <= QGis::WKBMultiPolygon25D )
       {
+        //ND: I suspect there's a bug here, in that this is NOT converting the geometry's WKB type,
+        //so the exported WKB has a different type to what the OGRGeometry is expecting.
+        //possibly this is handled already in OGR, but it should be fixed regardless by actually converting
+        //geom to the correct WKB type
         QgsWKBTypes::Type wkbType = QGis::fromOldWkbType( geom->wkbType() );
         if ( wkbType >= QgsWKBTypes::PointZ && wkbType <= QgsWKBTypes::MultiPolygonZ )
         {
@@ -1799,6 +1804,10 @@ OGRFeatureH QgsVectorFileWriter::createFeature( QgsFeature& feature )
       // set geometry (ownership is not passed to OGR)
       OGR_F_SetGeometry( poFeature, mGeom );
     }
+    else
+    {
+      OGR_F_SetGeometry( poFeature, createEmptyGeometry( mWkbType ) );
+    }
   }
   return poFeature;
 }
@@ -1848,7 +1857,10 @@ QgsVectorFileWriter::writeAsVectorFormat( QgsVectorLayer* layer,
     QString *newFilename,
     SymbologyExport symbologyExport,
     double symbologyScale,
-    const QgsRectangle* filterExtent )
+    const QgsRectangle* filterExtent,
+    QgsWKBTypes::Type overrideGeometryType,
+    bool forceMulti,
+    bool includeZ )
 {
   QgsCoordinateTransform* ct = 0;
   if ( destCRS && layer )
@@ -1857,7 +1869,7 @@ QgsVectorFileWriter::writeAsVectorFormat( QgsVectorLayer* layer,
   }
 
   QgsVectorFileWriter::WriterError error = writeAsVectorFormat( layer, fileName, fileEncoding, ct, driverName, onlySelected,
-      errorMessage, datasourceOptions, layerOptions, skipAttributeCreation, newFilename, symbologyExport, symbologyScale, filterExtent );
+      errorMessage, datasourceOptions, layerOptions, skipAttributeCreation, newFilename, symbologyExport, symbologyScale, filterExtent, overrideGeometryType, forceMulti, includeZ );
   delete ct;
   return error;
 }
@@ -1875,7 +1887,10 @@ QgsVectorFileWriter::WriterError QgsVectorFileWriter::writeAsVectorFormat( QgsVe
     QString *newFilename,
     SymbologyExport symbologyExport,
     double symbologyScale,
-    const QgsRectangle* filterExtent )
+    const QgsRectangle* filterExtent,
+    QgsWKBTypes::Type overrideGeometryType,
+    bool forceMulti,
+    bool includeZ )
 {
   if ( !layer )
   {
@@ -1896,7 +1911,18 @@ QgsVectorFileWriter::WriterError QgsVectorFileWriter::writeAsVectorFormat( QgsVe
     outputCRS = &layer->crs();
   }
 
-  QGis::WkbType wkbType = layer->wkbType();
+  QgsWKBTypes::Type destWkbType = QGis::fromOldWkbType( layer->wkbType() );
+  if ( overrideGeometryType != QgsWKBTypes::Unknown )
+  {
+    destWkbType = QgsWKBTypes::flatType( overrideGeometryType );
+    if ( QgsWKBTypes::hasZ( overrideGeometryType ) || includeZ )
+      destWkbType = QgsWKBTypes::addZ( destWkbType );
+  }
+  if ( forceMulti )
+  {
+    destWkbType = QgsWKBTypes::multiType( destWkbType );
+  }
+
   QgsFields fields = skipAttributeCreation ? QgsFields() : layer->fields();
 
   if ( layer->providerType() == "ogr" && layer->dataProvider() )
@@ -1912,19 +1938,21 @@ QgsVectorFileWriter::WriterError QgsVectorFileWriter::writeAsVectorFormat( QgsVe
     }
 
     // Shapefiles might contain multi types although wkbType() only reports singles
-    if ( layer->storageType() == "ESRI Shapefile" )
+    if ( layer->storageType() == "ESRI Shapefile" && !QgsWKBTypes::isMultiType( destWkbType ) )
     {
-      const QgsFeatureIds &ids = layer->selectedFeaturesIds();
-      QgsFeatureIterator fit = layer->getFeatures();
+      QgsFeatureRequest req;
+      if ( onlySelected )
+      {
+        req.setFilterFids( layer->selectedFeaturesIds() );
+      }
+      QgsFeatureIterator fit = layer->getFeatures( req );
       QgsFeature fet;
+
       while ( fit.nextFeature( fet ) )
       {
-        if ( onlySelected && !ids.contains( fet.id() ) )
-          continue;
-
-        if ( fet.constGeometry() && fet.constGeometry()->wkbType() == QGis::multiType( wkbType ) )
+        if ( fet.constGeometry() && !fet.constGeometry()->isEmpty() && QgsWKBTypes::isMultiType( fet.constGeometry()->geometry()->wkbType() ) )
         {
-          wkbType = QGis::multiType( wkbType );
+          destWkbType = QgsWKBTypes::multiType( destWkbType );
           break;
         }
       }
@@ -1947,7 +1975,7 @@ QgsVectorFileWriter::WriterError QgsVectorFileWriter::writeAsVectorFormat( QgsVe
   }
 
   QgsVectorFileWriter* writer =
-    new QgsVectorFileWriter( fileName, fileEncoding, fields, wkbType, outputCRS, driverName, datasourceOptions, layerOptions, newFilename, symbologyExport );
+    new QgsVectorFileWriter( fileName, fileEncoding, fields, QGis::fromNewWkbType( destWkbType ), outputCRS, driverName, datasourceOptions, layerOptions, newFilename, symbologyExport );
   writer->setSymbologyScaleDenominator( symbologyScale );
 
   if ( newFilename )

src/core/qgsvectorfilewriter.h

@@ -174,7 +174,11 @@ class CORE_EXPORT QgsVectorFileWriter
     @param newFilename QString pointer which will contain the new file name created (in case it is different to fileName).
     @param symbologyExport symbology to export
     @param symbologyScale scale of symbology
-    @param filterExtent if not a null pointer, only features intersecting the extent will be saved
+    @param filterExtent if not a null pointer, only features intersecting the extent will be saved (added in QGIS 2.4)
+    @param overrideGeometryType set to a valid geometry type to override the default geometry type for the layer. This parameter
+    allows for conversion of geometryless tables to null geometries, etc (added in QGIS 2.14)
+    @param forceMulti set to true to force creation of multi* geometries (added in QGIS 2.14)
+    @param includeZ set to true to include z dimension in output. This option is only valid if overrideGeometryType is set. (added in QGIS 2.14)
     */
     static WriterError writeAsVectorFormat( QgsVectorLayer* layer,
                                             const QString& fileName,
@@ -189,10 +193,33 @@ class CORE_EXPORT QgsVectorFileWriter
                                             QString *newFilename = 0,
                                             SymbologyExport symbologyExport = NoSymbology,
                                             double symbologyScale = 1.0,
-                                            const QgsRectangle* filterExtent = 0 // added in 2.4
+                                            const QgsRectangle* filterExtent = 0,
+                                            QgsWKBTypes::Type overrideGeometryType = QgsWKBTypes::Unknown,
+                                            bool forceMulti = false,
+                                            bool includeZ = false
                                           );
 
-    //! @note added in v2.2
+    /** Writes a layer out to a vector file.
+     * @param layer layer to write
+     * @param fileName file name to write to
+     * @param fileEncoding encoding to use
+     * @param ct
+     * @param driverName OGR driver to use
+     * @param onlySelected write only selected features of layer
+     * @param errorMessage pointer to buffer fo error message
+     * @param datasourceOptions list of OGR data source creation options
+     * @param layerOptions list of OGR layer creation options
+     * @param skipAttributeCreation only write geometries
+     * @param newFilename QString pointer which will contain the new file name created (in case it is different to fileName).
+     * @param symbologyExport symbology to export
+     * @param symbologyScale scale of symbology
+     * @param filterExtent if not a null pointer, only features intersecting the extent will be saved (added in QGIS 2.4)
+     * @param overrideGeometryType set to a valid geometry type to override the default geometry type for the layer. This parameter
+     * allows for conversion of geometryless tables to null geometries, etc (added in QGIS 2.14)
+     * @param forceMulti set to true to force creation of multi* geometries (added in QGIS 2.14)
+     * @param includeZ set to true to include z dimension in output. This option is only valid if overrideGeometryType is set. (added in QGIS 2.14)
+     * @note added in v2.2
+     */
     static WriterError writeAsVectorFormat( QgsVectorLayer* layer,
                                             const QString& fileName,
                                             const QString& fileEncoding,
@@ -206,7 +233,10 @@ class CORE_EXPORT QgsVectorFileWriter
                                             QString *newFilename = 0,
                                             SymbologyExport symbologyExport = NoSymbology,
                                             double symbologyScale = 1.0,
-                                            const QgsRectangle* filterExtent = 0 // added in 2.4
+                                            const QgsRectangle* filterExtent = 0,
+                                            QgsWKBTypes::Type overrideGeometryType = QgsWKBTypes::Unknown,
+                                            bool forceMulti = false,
+                                            bool includeZ = false
                                           );
 
     /** Create shapefile and initialize it */