[tests] Subdiagram position in vertically stacked diagrams (iterating subdiagrams backwards)

python/PyQt6/core/auto_generated/diagram/qgsstackeddiagram.sip.in

@@ -46,9 +46,12 @@ Adds a subdiagram to the stacked diagram object along with its corresponding set
           or more to the top (if stacked diagram is vertical).
 %End
 
-    QList< QgsDiagram * > subDiagrams() const;
+    QList< QgsDiagram * > subDiagrams( const QgsDiagramSettings &s ) const;
 %Docstring
 Returns an ordered list with the subdiagrams of the stacked diagram object.
+If the stacked diagram orientation is vertical, the list is returned backwards.
+
+:param s: stacked diagram settings
 %End
 
     QgsDiagramSettings *subDiagramSettings( const QgsDiagram *diagram ) const;

python/core/auto_generated/diagram/qgsstackeddiagram.sip.in

@@ -46,9 +46,12 @@ Adds a subdiagram to the stacked diagram object along with its corresponding set
           or more to the top (if stacked diagram is vertical).
 %End
 
-    QList< QgsDiagram * > subDiagrams() const;
+    QList< QgsDiagram * > subDiagrams( const QgsDiagramSettings &s ) const;
 %Docstring
 Returns an ordered list with the subdiagrams of the stacked diagram object.
+If the stacked diagram orientation is vertical, the list is returned backwards.
+
+:param s: stacked diagram settings
 %End
 
     QgsDiagramSettings *subDiagramSettings( const QgsDiagram *diagram ) const;

src/core/diagram/qgsstackeddiagram.cpp

@@ -38,12 +38,26 @@ void QgsStackedDiagram::addSubDiagram( QgsDiagram *diagram, QgsDiagramSettings *
   mSubDiagrams.append( DiagramData{diagram, s} );
 }
 
-QList< QgsDiagram * > QgsStackedDiagram::subDiagrams() const
+QList< QgsDiagram * > QgsStackedDiagram::subDiagrams( const QgsDiagramSettings &s ) const
 {
   QList< QgsDiagram * > diagrams;
-  for ( const auto &item : std::as_const( mSubDiagrams ) )
+
+  if ( s.stackedDiagramMode == QgsDiagramSettings::Horizontal )
   {
-    diagrams.append( item.diagram );
+    for ( const auto &item : std::as_const( mSubDiagrams ) )
+    {
+      diagrams.append( item.diagram );
+    }
+  }
+  else
+  {
+    // We'll draw vertical diagrams backwards,
+    // so we return the subdiagrams in reverse order
+    QList< DiagramData >::const_reverse_iterator iter = mSubDiagrams.rbegin();
+    for ( ; iter != mSubDiagrams.rend(); ++iter )
+    {
+      diagrams.append( iter->diagram );
+    }
   }
   return diagrams;
 }
@@ -71,7 +85,7 @@ void QgsStackedDiagram::subDiagramPosition( QPointF &newPos, const QgsRenderCont
   }
   else
   {
-    newPos += QPointF( 0, size.height() + spacing );
+    newPos -= QPointF( 0, size.height() + spacing );
   }
 }
 

src/core/diagram/qgsstackeddiagram.h

@@ -62,8 +62,12 @@ class CORE_EXPORT QgsStackedDiagram : public QgsDiagram SIP_NODEFAULTCTORS
      */
     void addSubDiagram( QgsDiagram *diagram, QgsDiagramSettings *s );
 
-    //! Returns an ordered list with the subdiagrams of the stacked diagram object.
-    QList< QgsDiagram * > subDiagrams() const;
+    /**
+     * Returns an ordered list with the subdiagrams of the stacked diagram object.
+     * If the stacked diagram orientation is vertical, the list is returned backwards.
+     * \param s stacked diagram settings
+     */
+    QList< QgsDiagram * > subDiagrams( const QgsDiagramSettings &s ) const;
 
     //! Returns the settings associated to the \a diagram.
     QgsDiagramSettings *subDiagramSettings( const QgsDiagram *diagram ) const;

src/core/qgsdiagramrenderer.cpp

@@ -507,7 +507,7 @@ void QgsDiagramRenderer::renderDiagram( const QgsFeature &feature, QgsRenderCont
   {
     // Iterate subdiagrams and render them individually
     QgsStackedDiagram *stackedDiagram = qgis::down_cast< QgsStackedDiagram *>( mDiagram.get() );
-    QList< QgsDiagram * > subDiagrams = stackedDiagram->subDiagrams();
+    QList< QgsDiagram * > subDiagrams = stackedDiagram->subDiagrams( s );
     QPointF newPos = pos; // Each subdiagram will have its own newPos
 
     for ( const auto &subDiagram : std::as_const( subDiagrams ) )

tests/src/core/testqgsstackeddiagram.cpp

@@ -194,6 +194,84 @@ class TestQgsStackedDiagram : public QgsTest
       QGSVERIFYRENDERMAPSETTINGSCHECK( "stackedhistograms", "stackedhistograms", *mMapSettings, 200, 15 );
     }
 
+    void testVerticallyStackedHistograms()
+    {
+      // Histogram 1
+      QgsDiagramSettings ds1;
+      QColor col1 = Qt::blue;
+      QColor col2 = Qt::red;
+      QColor col3 = Qt::yellow;
+      QColor col4 = Qt::green;
+      col1.setAlphaF( 0.5 );
+      col2.setAlphaF( 0.5 );
+      col3.setAlphaF( 0.5 );
+      col4.setAlphaF( 0.5 );
+      ds1.categoryColors = QList<QColor>() << col1 << col2 << col3 << col4;
+      ds1.categoryAttributes = QList<QString>() << QStringLiteral( "\"maennlich_ab_65\"" ) << QStringLiteral( "\"maennlich_18_64\"" ) << QStringLiteral( "\"maennlich_6_17\"" ) << QStringLiteral( "\"maennlich_unter_6\"" );  //#spellok
+      ds1.minimumScale = -1;
+      ds1.maximumScale = -1;
+      ds1.minimumSize = 0;
+      ds1.penColor = Qt::black;
+      ds1.penWidth = .5;
+      ds1.scaleByArea = true;
+      ds1.sizeType = Qgis::RenderUnit::Millimeters;
+      ds1.rotationOffset = 0;
+      ds1.diagramOrientation = QgsDiagramSettings::Up;
+
+      // Histogram 2
+      QgsDiagramSettings ds2;
+      col1 = Qt::blue;
+      col2 = Qt::red;
+      col3 = Qt::yellow;
+      col4 = Qt::green;
+      col1.setAlphaF( 0.5 );
+      col2.setAlphaF( 0.5 );
+      col3.setAlphaF( 0.5 );
+      col4.setAlphaF( 0.5 );
+      ds2.categoryColors = QList<QColor>() << col1 << col2 << col3 << col4;
+      ds2.categoryAttributes = QList<QString>() << QStringLiteral( "\"weiblich_ab_65\"" ) << QStringLiteral( "\"weiblich_18_64\"" ) << QStringLiteral( "\"weiblich_6_17\"" ) << QStringLiteral( "\"weiblich_unter_6\"" );  //#spellok
+      ds2.minimumScale = -1;
+      ds2.maximumScale = -1;
+      ds2.minimumSize = 0;
+      ds2.penColor = Qt::black;
+      ds2.penWidth = .5;
+      ds2.scaleByArea = true;
+      ds2.sizeType = Qgis::RenderUnit::Millimeters;
+      ds2.rotationOffset = 0;
+      ds2.diagramOrientation = QgsDiagramSettings::Down;
+
+      QgsDiagramSettings ds;
+      ds.stackedDiagramMode = QgsDiagramSettings::Vertical;
+      ds.categoryAttributes = ds1.categoryAttributes + ds2.categoryAttributes;
+      ds.setStackedDiagramSpacingUnit( Qgis::RenderUnit::Pixels );
+      ds.setStackedDiagramSpacing( 0 );
+
+      QgsStackedDiagram *stackedDiagram = new QgsStackedDiagram();
+      stackedDiagram->addSubDiagram( new QgsHistogramDiagram(), &ds1 );
+      stackedDiagram->addSubDiagram( new QgsHistogramDiagram(), &ds2 );
+
+      QgsLinearlyInterpolatedDiagramRenderer *dr = new QgsLinearlyInterpolatedDiagramRenderer();
+      dr->setLowerValue( 0.0 );
+      dr->setLowerSize( QSizeF( 0.0, 0.0 ) );
+      dr->setUpperValue( 15000 );
+      dr->setUpperSize( QSizeF( 20, 20 ) );
+      dr->setClassificationField( QStringLiteral( "max(\"maennlich_18_64\", \"maennlich_ab_65\", \"weiblich_unter_6\", \"weiblich_6_17\", \"weiblich_18_64\", \"weiblich_ab_65\")" ) );  //#spellok
+      dr->setDiagram( stackedDiagram );
+      dr->setDiagramSettings( ds );
+      mPointsLayer->setDiagramRenderer( dr );
+
+      QgsDiagramLayerSettings dls = QgsDiagramLayerSettings();
+      dls.setPlacement( QgsDiagramLayerSettings::OverPoint );
+      dls.setShowAllDiagrams( true );
+      mPointsLayer->setDiagramLayerSettings( dls );
+
+      const QgsRectangle extent( 9.7, 53.5, 9.95, 53.6 );
+      mMapSettings->setExtent( extent );
+      mMapSettings->setFlag( Qgis::MapSettingsFlag::ForceVectorOutput );
+      mMapSettings->setOutputDpi( 96 );
+      QGSVERIFYRENDERMAPSETTINGSCHECK( "verticallystackedhistograms", "verticallystackedhistograms", *mMapSettings, 200, 15 );
+    }
+
     void testStackedHistogramsWithSpacing()
     {
       // Histogram 1