[processing] native save selected features algorithm

nirvn · nirvn · commit 04ee85f0e8e8 · 2017-09-15T15:51:30.000+07:00
diff --git a/python/plugins/processing/algs/help/qgis.yaml b/python/plugins/processing/algs/help/qgis.yaml
@@ -499,11 +499,6 @@ qgis:reprojectlayer: >
 
   Attributes are not modified by this algorithm.
 
-qgis:saveselectedfeatures: >
-  This algorithm creates a new layer with all the selected features in a given vector layer.
-
-  If the selected layer has no selected features, all features will be added to the resulting feature.
-
 qgis:selectbyattribute: >
   This algorithm creates a selection in a vector layer. The criteria for selected features is defined based on the values of an attribute from the input layer.
 
diff --git a/python/plugins/processing/algs/qgis/QGISAlgorithmProvider.py b/python/plugins/processing/algs/qgis/QGISAlgorithmProvider.py
@@ -129,7 +129,6 @@
 from .Relief import Relief
 from .ReverseLineDirection import ReverseLineDirection
 from .Ruggedness import Ruggedness
-from .SaveSelectedFeatures import SaveSelectedFeatures
 from .SelectByAttribute import SelectByAttribute
 from .SelectByExpression import SelectByExpression
 from .ServiceAreaFromLayer import ServiceAreaFromLayer
@@ -266,7 +265,6 @@ def getAlgs(self):
                 Relief(),
                 ReverseLineDirection(),
                 Ruggedness(),
-                SaveSelectedFeatures(),
                 SelectByAttribute(),
                 SelectByExpression(),
                 ServiceAreaFromLayer(),
diff --git a/python/plugins/processing/algs/qgis/SaveSelectedFeatures.py b/python/plugins/processing/algs/qgis/SaveSelectedFeatures.py
diff --git a/src/core/processing/qgsnativealgorithms.cpp b/src/core/processing/qgsnativealgorithms.cpp
@@ -80,10 +80,71 @@ void QgsNativeAlgorithms::loadAlgorithms()
   addAlgorithm( new QgsExtractByLocationAlgorithm() );
   addAlgorithm( new QgsFixGeometriesAlgorithm() );
   addAlgorithm( new QgsMergeLinesAlgorithm() );
+  addAlgorithm( new QgsSaveSelectedFeatures() );
   addAlgorithm( new QgsSmoothAlgorithm() );
   addAlgorithm( new QgsSimplifyAlgorithm() );
 }
 
+void QgsSaveSelectedFeatures::initAlgorithm( const QVariantMap & )
+{
+  addParameter( new QgsProcessingParameterVectorLayer( QStringLiteral( "INPUT" ), QObject::tr( "Input layer" ) ) );
+  addParameter( new QgsProcessingParameterFeatureSink( QStringLiteral( "OUTPUT" ), QObject::tr( "Selected features" ), QgsProcessing::TypeVectorPoint ) );
+}
+
+QString QgsSaveSelectedFeatures::shortHelpString() const
+{
+  return QObject::tr( "This algorithm creates a new layer with all the selected features in a given vector layer.\n\n"
+                      "If the selected layer has no selected features, all features will be added to the resulting feature." );
+}
+
+QgsSaveSelectedFeatures *QgsSaveSelectedFeatures::createInstance() const
+{
+  return new QgsSaveSelectedFeatures();
+}
+
+QVariantMap QgsSaveSelectedFeatures::processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
+{
+  QgsVectorLayer *selectLayer = parameterAsVectorLayer( parameters, QStringLiteral( "INPUT" ), context );
+
+  QString dest;
+  std::unique_ptr< QgsFeatureSink > sink( parameterAsSink( parameters, QStringLiteral( "OUTPUT" ), context, dest, selectLayer->fields(), selectLayer->wkbType(), selectLayer->sourceCrs() ) );
+  if ( !sink )
+    return QVariantMap();
+
+  QgsFeatureIterator it;
+  QgsFeature feat;
+
+  int count = selectLayer->selectedFeatureCount();
+  if ( count > 0 )
+  {
+    it = selectLayer->getSelectedFeatures();
+  }
+  else
+  {
+    count = selectLayer->featureCount();
+    it = selectLayer->getFeatures();
+  }
+
+  int current = 0;
+  double step = count > 0 ? 100.0 / count : 1;
+
+  while ( it.nextFeature( feat ) )
+  {
+    if ( feedback->isCanceled() )
+    {
+      break;
+    }
+
+    sink->addFeature( feat, QgsFeatureSink::FastInsert );
+
+    feedback->setProgress( current++ * step );
+  }
+
+  QVariantMap outputs;
+  outputs.insert( QStringLiteral( "OUTPUT" ), dest );
+  return outputs;
+}
+
 void QgsCentroidAlgorithm::initAlgorithm( const QVariantMap & )
 {
   addParameter( new QgsProcessingParameterFeatureSource( QStringLiteral( "INPUT" ), QObject::tr( "Input layer" ) ) );
diff --git a/src/core/processing/qgsnativealgorithms.h b/src/core/processing/qgsnativealgorithms.h
@@ -48,6 +48,29 @@ class QgsNativeAlgorithms: public QgsProcessingProvider
 
 };
 
+/**
+ * Native save selected features algorithm.
+ */
+class QgsSaveSelectedFeatures : public QgsProcessingAlgorithm
+{
+
+  public:
+
+    QgsSaveSelectedFeatures() = default;
+    void initAlgorithm( const QVariantMap &configuration = QVariantMap() ) override;
+    QString name() const override { return QStringLiteral( "saveselectedfeatures" ); }
+    QString displayName() const override { return QObject::tr( "Save Selected Features" ); }
+    QStringList tags() const override { return QObject::tr( "selection,save" ).split( ',' ); }
+    QString group() const override { return QObject::tr( "Vector general" ); }
+    QString shortHelpString() const override;
+    QgsSaveSelectedFeatures *createInstance() const override SIP_FACTORY;
+
+  protected:
+
+    virtual QVariantMap processAlgorithm( const QVariantMap &parameters,
+                                          QgsProcessingContext &context, QgsProcessingFeedback *feedback ) override;
+};
+
 /**
  * Native centroid algorithm.
  */
