Merge pull request #3026 from nirvn/centroid_fill_parts

[FEATURE] add setting to control centroid fill point rendering on all parts or a single part of multi-features

python/core/symbology-ng/qgsfillsymbollayerv2.sip

@@ -893,4 +893,11 @@ class QgsCentroidFillSymbolLayerV2 : QgsFillSymbolLayerV2
 
     void setPointOnSurface( bool pointOnSurface );
     bool pointOnSurface() const;
+
+    /** Sets whether a point is drawn for all parts or only on the biggest part of multi-part features.
+     * @note added in 2.16 */
+    void setPointOnAllParts( bool pointOnAllParts );
+    /** Returns whether a point is drawn for all parts or only on the biggest part of multi-part features.
+     * @note added in 2.16 */
+    bool pointOnAllParts() const;
 };

python/core/symbology-ng/qgssymbolv2.sip

@@ -317,6 +317,24 @@ class QgsSymbolV2RenderContext
     //! @note added in 2.4
     const QgsFields* fields() const;
 
+    /** Part count of current geometry
+     * @note added in QGIS 2.16
+     */
+    int geometryPartCount() const;
+    /** Sets the part count of current geometry
+     * @note added in QGIS 2.16
+     */
+    void setGeometryPartCount( int count );
+
+    /** Part number of current geometry
+     * @note added in QGIS 2.16
+     */
+    int geometryPartNum() const;
+    /** Sets the part number of current geometry
+     * @note added in QGIS 2.16
+     */
+    void setGeometryPartNum( int num );
+
     double outputLineWidth( double width ) const;
     double outputPixelSize( double size ) const;
 

src/core/symbology-ng/qgsfillsymbollayerv2.cpp

@@ -19,6 +19,8 @@
 #include "qgssymbollayerv2utils.h"
 #include "qgsdxfexport.h"
 #include "qgsexpression.h"
+#include "qgsgeometry.h"
+#include "qgsgeometrycollectionv2.h"
 #include "qgsrendercontext.h"
 #include "qgsproject.h"
 #include "qgssvgcache.h"
@@ -3384,7 +3386,7 @@ QSet<QString> QgsPointPatternFillSymbolLayer::usedAttributes() const
 //////////////
 
 
-QgsCentroidFillSymbolLayerV2::QgsCentroidFillSymbolLayerV2(): mMarker( nullptr ), mPointOnSurface( false )
+QgsCentroidFillSymbolLayerV2::QgsCentroidFillSymbolLayerV2(): mMarker( nullptr ), mPointOnSurface( false ), mPointOnAllParts( true )
 {
   setSubSymbol( new QgsMarkerSymbolV2() );
 }
@@ -3400,6 +3402,8 @@ QgsSymbolLayerV2* QgsCentroidFillSymbolLayerV2::create( const QgsStringMap& prop
 
   if ( properties.contains( "point_on_surface" ) )
     sl->setPointOnSurface( properties["point_on_surface"].toInt() != 0 );
+  if ( properties.contains( "point_on_all_parts" ) )
+    sl->setPointOnAllParts( properties["point_on_all_parts"].toInt() != 0 );
 
   return sl;
 }
@@ -3419,6 +3423,9 @@ void QgsCentroidFillSymbolLayerV2::startRender( QgsSymbolV2RenderContext& contex
 {
   mMarker->setAlpha( context.alpha() );
   mMarker->startRender( context.renderContext(), context.fields() );
+
+  mCurrentFeatureId = -1;
+  mBiggestPartIndex = 0;
 }
 
 void QgsCentroidFillSymbolLayerV2::stopRender( QgsSymbolV2RenderContext& context )
@@ -3430,14 +3437,51 @@ void QgsCentroidFillSymbolLayerV2::renderPolygon( const QPolygonF& points, QList
 {
   Q_UNUSED( rings );
 
-  QPointF centroid = mPointOnSurface ? QgsSymbolLayerV2Utils::polygonPointOnSurface( points ) : QgsSymbolLayerV2Utils::polygonCentroid( points );
-  mMarker->renderPoint( centroid, context.feature(), context.renderContext(), -1, context.selected() );
+  if ( !mPointOnAllParts )
+  {
+    const QgsFeature* feature = context.feature();
+    if ( feature )
+    {
+      if ( feature->id() != mCurrentFeatureId )
+      {
+        mCurrentFeatureId = feature->id();
+        mBiggestPartIndex = 1;
+
+        if ( context.geometryPartCount() > 1 )
+        {
+          const QgsGeometry *geom = feature->constGeometry();
+          const QgsGeometryCollectionV2* geomCollection = dynamic_cast<const QgsGeometryCollectionV2*>( geom->geometry() );
+
+          double area = 0;
+          double areaBiggest = 0;
+          for ( int i = 0; i < context.geometryPartCount(); ++i )
+          {
+            area = geomCollection->geometryN( i )->area();
+            if ( area > areaBiggest )
+            {
+              areaBiggest = area;
+              mBiggestPartIndex = i + 1;
+            }
+          }
+        }
+      }
+    }
+  }
+
+  QgsDebugMsg( QString( "num: %1, count: %2" ).arg( context.geometryPartNum() ).arg( context.geometryPartCount() ) );
+
+  if ( mPointOnAllParts || ( context.geometryPartNum() == mBiggestPartIndex ) )
+  {
+    QPointF centroid = mPointOnSurface ? QgsSymbolLayerV2Utils::polygonPointOnSurface( points ) : QgsSymbolLayerV2Utils::polygonCentroid( points );
+    mMarker->renderPoint( centroid, context.feature(), context.renderContext(), -1, context.selected() );
+  }
 }
 
 QgsStringMap QgsCentroidFillSymbolLayerV2::properties() const
 {
   QgsStringMap map;
   map["point_on_surface"] = QString::number( mPointOnSurface );
+  map["point_on_all_parts"] = QString::number( mPointOnAllParts );
   return map;
 }
 
@@ -3448,6 +3492,7 @@ QgsCentroidFillSymbolLayerV2* QgsCentroidFillSymbolLayerV2::clone() const
   x->mColor = mColor;
   x->setSubSymbol( mMarker->clone() );
   x->setPointOnSurface( mPointOnSurface );
+  x->setPointOnAllParts( mPointOnAllParts );
   copyPaintEffect( x );
   return x;
 }

src/core/symbology-ng/qgsfillsymbollayerv2.h

@@ -1095,9 +1095,20 @@ class CORE_EXPORT QgsCentroidFillSymbolLayerV2 : public QgsFillSymbolLayerV2
     void setPointOnSurface( bool pointOnSurface ) { mPointOnSurface = pointOnSurface; }
     bool pointOnSurface() const { return mPointOnSurface; }
 
+    /** Sets whether a point is drawn for all parts or only on the biggest part of multi-part features.
+     * @note added in 2.16 */
+    void setPointOnAllParts( bool pointOnAllParts ) { mPointOnAllParts = pointOnAllParts; }
+    /** Returns whether a point is drawn for all parts or only on the biggest part of multi-part features.
+     * @note added in 2.16 */
+    bool pointOnAllParts() const { return mPointOnAllParts; }
+
   protected:
     QgsMarkerSymbolV2* mMarker;
     bool mPointOnSurface;
+    bool mPointOnAllParts;
+
+    QgsFeatureId mCurrentFeatureId;
+    int mBiggestPartIndex;
 };
 
 #endif

src/core/symbology-ng/qgssymbolv2.cpp

@@ -733,11 +733,14 @@ void QgsSymbolV2::renderFeature( const QgsFeature& feature, QgsRenderContext& co
     deleteSegmentizedGeometry = true;
   }
 
+  mSymbolRenderContext->setGeometryPartCount( segmentizedGeometry->geometry()->partCount() );
+  mSymbolRenderContext->setGeometryPartNum( 1 );
+
   if ( mSymbolRenderContext->expressionContextScope() )
   {
     context.expressionContext().appendScope( mSymbolRenderContext->expressionContextScope() );
     QgsExpressionContextUtils::updateSymbolScope( this, mSymbolRenderContext->expressionContextScope() );
-    mSymbolRenderContext->expressionContextScope()->setVariable( QgsExpressionContext::EXPR_GEOMETRY_PART_COUNT, segmentizedGeometry->geometry()->partCount() );
+    mSymbolRenderContext->expressionContextScope()->setVariable( QgsExpressionContext::EXPR_GEOMETRY_PART_COUNT, mSymbolRenderContext->geometryPartCount() );
     mSymbolRenderContext->expressionContextScope()->setVariable( QgsExpressionContext::EXPR_GEOMETRY_PART_NUM, 1 );
   }
 
@@ -833,6 +836,7 @@ void QgsSymbolV2::renderFeature( const QgsFeature& feature, QgsRenderContext& co
 
       for ( int i = 0; i < mp->numGeometries(); ++i )
       {
+        mSymbolRenderContext->setGeometryPartNum( i + 1 );
         mSymbolRenderContext->expressionContextScope()->setVariable( QgsExpressionContext::EXPR_GEOMETRY_PART_NUM, i + 1 );
 
         const QgsPointV2* point = static_cast< const QgsPointV2* >( mp->geometryN( i ) );
@@ -868,6 +872,7 @@ void QgsSymbolV2::renderFeature( const QgsFeature& feature, QgsRenderContext& co
 
       for ( unsigned int i = 0; i < num && wkbPtr; ++i )
       {
+        mSymbolRenderContext->setGeometryPartNum( i + 1 );
         mSymbolRenderContext->expressionContextScope()->setVariable( QgsExpressionContext::EXPR_GEOMETRY_PART_NUM, i + 1 );
 
         if ( geomCollection )
@@ -914,6 +919,7 @@ void QgsSymbolV2::renderFeature( const QgsFeature& feature, QgsRenderContext& co
 
       for ( unsigned int i = 0; i < num && wkbPtr; ++i )
       {
+        mSymbolRenderContext->setGeometryPartNum( i + 1 );
         mSymbolRenderContext->expressionContextScope()->setVariable( QgsExpressionContext::EXPR_GEOMETRY_PART_NUM, i + 1 );
 
         if ( geomCollection )
@@ -1002,7 +1008,9 @@ QgsSymbolV2RenderContext::QgsSymbolV2RenderContext( QgsRenderContext& c, QgsSymb
     mSelected( selected ),
     mRenderHints( renderHints ),
     mFeature( f ),
-    mFields( fields )
+    mFields( fields ),
+    mGeometryPartCount( 0 ),
+    mGeometryPartNum( 0 )
 {
 }
 
@@ -1440,6 +1448,8 @@ void QgsMarkerSymbolV2::renderPointUsingLayer( QgsMarkerSymbolLayerV2* layer, QP
 void QgsMarkerSymbolV2::renderPoint( QPointF point, const QgsFeature* f, QgsRenderContext& context, int layerIdx, bool selected )
 {
   QgsSymbolV2RenderContext symbolContext( context, outputUnit(), mAlpha, selected, mRenderHints, f, nullptr, mapUnitScale() );
+  symbolContext.setGeometryPartCount( symbolRenderContext()->geometryPartCount() );
+  symbolContext.setGeometryPartNum( symbolRenderContext()->geometryPartNum() );
 
   if ( layerIdx != -1 )
   {
@@ -1646,6 +1656,8 @@ void QgsLineSymbolV2::renderPolyline( const QPolygonF& points, const QgsFeature*
   //save old painter
   QPainter* renderPainter = context.painter();
   QgsSymbolV2RenderContext symbolContext( context, outputUnit(), mAlpha, selected, mRenderHints, f, nullptr, mapUnitScale() );
+  symbolContext.setGeometryPartCount( symbolRenderContext()->geometryPartCount() );
+  symbolContext.setGeometryPartNum( symbolRenderContext()->geometryPartNum() );
 
   if ( layerIdx != -1 )
   {
@@ -1723,6 +1735,8 @@ QgsFillSymbolV2::QgsFillSymbolV2( const QgsSymbolLayerV2List& layers )
 void QgsFillSymbolV2::renderPolygon( const QPolygonF& points, QList<QPolygonF>* rings, const QgsFeature* f, QgsRenderContext& context, int layerIdx, bool selected )
 {
   QgsSymbolV2RenderContext symbolContext( context, outputUnit(), mAlpha, selected, mRenderHints, f, nullptr, mapUnitScale() );
+  symbolContext.setGeometryPartCount( symbolRenderContext()->geometryPartCount() );
+  symbolContext.setGeometryPartNum( symbolRenderContext()->geometryPartNum() );
 
   if ( layerIdx != -1 )
   {

src/core/symbology-ng/qgssymbolv2.h

@@ -379,6 +379,24 @@ class CORE_EXPORT QgsSymbolV2RenderContext
     //! @note added in 2.4
     const QgsFields* fields() const { return mFields; }
 
+    /** Part count of current geometry
+     * @note added in QGIS 2.16
+     */
+    int geometryPartCount() const { return mGeometryPartCount; }
+    /** Sets the part count of current geometry
+     * @note added in QGIS 2.16
+     */
+    void setGeometryPartCount( int count ) { mGeometryPartCount = count; }
+
+    /** Part number of current geometry
+     * @note added in QGIS 2.16
+     */
+    int geometryPartNum() const { return mGeometryPartNum; }
+    /** Sets the part number of current geometry
+     * @note added in QGIS 2.16
+     */
+    void setGeometryPartNum( int num ) { mGeometryPartNum = num; }
+
     double outputLineWidth( double width ) const;
     double outputPixelSize( double size ) const;
 
@@ -410,6 +428,8 @@ class CORE_EXPORT QgsSymbolV2RenderContext
     int mRenderHints;
     const QgsFeature* mFeature; //current feature
     const QgsFields* mFields;
+    int mGeometryPartCount;
+    int mGeometryPartNum;
 
 
     QgsSymbolV2RenderContext( const QgsSymbolV2RenderContext& rh );

src/gui/symbology-ng/qgssymbollayerv2widget.cpp

@@ -2737,9 +2737,8 @@ void QgsCentroidFillSymbolLayerV2Widget::setSymbolLayer( QgsSymbolLayerV2* layer
   mLayer = static_cast<QgsCentroidFillSymbolLayerV2*>( layer );
 
   // set values
-  mDrawInsideCheckBox->blockSignals( true );
-  mDrawInsideCheckBox->setChecked( mLayer->pointOnSurface() );
-  mDrawInsideCheckBox->blockSignals( false );
+  whileBlocking( mDrawInsideCheckBox )->setChecked( mLayer->pointOnSurface() );
+  whileBlocking( mDrawAllPartsCheckBox )->setChecked( mLayer->pointOnAllParts() );
 }
 
 QgsSymbolLayerV2* QgsCentroidFillSymbolLayerV2Widget::symbolLayer()
@@ -2753,6 +2752,12 @@ void QgsCentroidFillSymbolLayerV2Widget::on_mDrawInsideCheckBox_stateChanged( in
   emit changed();
 }
 
+void QgsCentroidFillSymbolLayerV2Widget::on_mDrawAllPartsCheckBox_stateChanged( int state )
+{
+  mLayer->setPointOnAllParts( state == Qt::Checked );
+  emit changed();
+}
+
 ///////////////
 
 QgsRasterFillSymbolLayerWidget::QgsRasterFillSymbolLayerWidget( const QgsVectorLayer *vl, QWidget *parent )

src/gui/symbology-ng/qgssymbollayerv2widget.h

@@ -627,6 +627,7 @@ class GUI_EXPORT QgsCentroidFillSymbolLayerV2Widget : public QgsSymbolLayerV2Wid
 
   private slots:
     void on_mDrawInsideCheckBox_stateChanged( int state );
+    void on_mDrawAllPartsCheckBox_stateChanged( int state );
 
 };
 

src/ui/symbollayer/widget_centroidfill.ui

@@ -15,7 +15,7 @@
   </property>
   <layout class="QVBoxLayout" name="verticalLayout">
    <item>
-    <layout class="QHBoxLayout" name="horizontalLayout">
+    <layout class="QHBoxLayout" name="horizontalLayout_1">
      <item>
       <widget class="QCheckBox" name="mDrawInsideCheckBox">
        <property name="text">
@@ -41,6 +41,20 @@
      </item>
     </layout>
    </item>
+   <item>
+    <layout class="QHBoxLayout" name="horizontalLayout">
+     <item>
+      <widget class="QCheckBox" name="mDrawAllPartsCheckBox">
+       <property name="text">
+        <string>Draw point on every part of multi-part features</string>
+       </property>
+       <property name="toolTip">
+        <string>When unchecked, a single point will be drawn on the biggest part of multi-part features</string>
+       </property>
+      </widget>
+     </item>
+    </layout>
+   </item>
    <item>
     <spacer>
      <property name="orientation">

tests/src/core/CMakeLists.txt

@@ -145,6 +145,7 @@ ADD_QGIS_TEST(invertedpolygontest testqgsinvertedpolygonrenderer.cpp )
 ADD_QGIS_TEST(labelingenginev2 testqgslabelingenginev2.cpp)
 ADD_QGIS_TEST(layertree testqgslayertree.cpp)
 ADD_QGIS_TEST(legendrenderertest testqgslegendrenderer.cpp )
+ADD_QGIS_TEST(centroidfillsymboltest testqgscentroidfillsymbol.cpp )
 ADD_QGIS_TEST(linefillsymboltest testqgslinefillsymbol.cpp )
 ADD_QGIS_TEST(maplayerstylemanager testqgsmaplayerstylemanager.cpp )
 ADD_QGIS_TEST(maplayertest testqgsmaplayer.cpp)