Update diagram renderer to use rotation in degrees clockwise

doc/api_break.dox

@@ -1024,6 +1024,7 @@ QgsDiagramSettings        {#qgis_api_break_3_0_QgsDiagramSettings}
 - The SizeType enum was removed. Use QgsUnitTypes.RenderUnit instead.
 - readXml() and writeXml() do not take QgsVectorLayer as an argument anymore.
 - transparency was removed. Use opacity instead.
+- angleOffset was removed. Use rotationOffset instead.
 
 
 QgsDial        {#qgis_api_break_3_0_QgsDial}

python/core/qgsdiagramrenderer.sip

@@ -365,7 +365,12 @@ Opacity, from 0 (transparent) to 1.0 (opaque)
 %End
 
     bool scaleByArea;
-    int angleOffset;
+
+    double rotationOffset;
+%Docstring
+ Rotation offset, in degrees clockwise from horizontal.
+.. versionadded:: 3.0
+%End
 
     bool scaleBasedVisibility;
     double minScaleDenominator;

src/app/qgsdiagramproperties.cpp

@@ -147,10 +147,10 @@ QgsDiagramProperties::QgsDiagramProperties( QgsVectorLayer *layer, QWidget *pare
   mScaleDependencyComboBox->addItem( tr( "Area" ), true );
   mScaleDependencyComboBox->addItem( tr( "Diameter" ), false );
 
-  mAngleOffsetComboBox->addItem( tr( "Top" ), 90 * 16 );
+  mAngleOffsetComboBox->addItem( tr( "Top" ), 270 );
   mAngleOffsetComboBox->addItem( tr( "Right" ), 0 );
-  mAngleOffsetComboBox->addItem( tr( "Bottom" ), 270 * 16 );
+  mAngleOffsetComboBox->addItem( tr( "Bottom" ), 90 );
-  mAngleOffsetComboBox->addItem( tr( "Left" ), 180 * 16 );
+  mAngleOffsetComboBox->addItem( tr( "Left" ), 180 );
 
   QgsSettings settings;
 
@@ -283,7 +283,7 @@ QgsDiagramProperties::QgsDiagramProperties( QgsVectorLayer *layer, QWidget *pare
         mLabelPlacementComboBox->setCurrentIndex( 1 );
       }
 
-      mAngleOffsetComboBox->setCurrentIndex( mAngleOffsetComboBox->findData( settingList.at( 0 ).angleOffset ) );
+      mAngleOffsetComboBox->setCurrentIndex( mAngleOffsetComboBox->findData( settingList.at( 0 ).rotationOffset ) );
 
       mOrientationLeftButton->setProperty( "direction", QgsDiagramSettings::Left );
       mOrientationRightButton->setProperty( "direction", QgsDiagramSettings::Right );
@@ -779,7 +779,7 @@ void QgsDiagramProperties::apply()
   ds.scaleBasedVisibility = mScaleVisibilityGroupBox->isChecked();
 
   // Diagram angle offset (pie)
-  ds.angleOffset = mAngleOffsetComboBox->currentData().toInt();
+  ds.rotationOffset = mAngleOffsetComboBox->currentData().toInt();
 
   // Diagram orientation (histogram)
   ds.diagramOrientation = static_cast<QgsDiagramSettings::DiagramOrientation>( mOrientationButtonGroup->checkedButton()->property( "direction" ).toInt() );

src/core/diagram/qgspiediagram.cpp

@@ -138,7 +138,7 @@ void QgsPieDiagram::renderDiagram( const QgsFeature &feature, QgsRenderContext &
         }
         else
         {
-          p->drawPie( baseX, baseY, w, h, totalAngle + s.angleOffset, currentAngle );
+          p->drawPie( baseX, baseY, w, h, totalAngle - s.rotationOffset * 16.0, currentAngle );
         }
         totalAngle += currentAngle;
       }

src/core/qgsdiagramrenderer.cpp

@@ -255,7 +255,10 @@ void QgsDiagramSettings::readXml( const QDomElement &elem )
 
   barWidth = elem.attribute( QStringLiteral( "barWidth" ) ).toDouble();
 
-  angleOffset = elem.attribute( QStringLiteral( "angleOffset" ) ).toInt();
+  if ( elem.hasAttribute( QStringLiteral( "angleOffset" ) ) )
+    rotationOffset = fmod( 360.0 - elem.attribute( QStringLiteral( "angleOffset" ) ).toInt() / 16.0, 360.0 );
+  else
+    rotationOffset = elem.attribute( QStringLiteral( "rotationOffset" ) ).toDouble();
 
   minimumSize = elem.attribute( QStringLiteral( "minimumSize" ) ).toDouble();
 
@@ -374,7 +377,7 @@ void QgsDiagramSettings::writeXml( QDomElement &rendererElem, QDomDocument &doc
 
   categoryElem.setAttribute( QStringLiteral( "barWidth" ), QString::number( barWidth ) );
   categoryElem.setAttribute( QStringLiteral( "minimumSize" ), QString::number( minimumSize ) );
-  categoryElem.setAttribute( QStringLiteral( "angleOffset" ), QString::number( angleOffset ) );
+  categoryElem.setAttribute( QStringLiteral( "rotationOffset" ), QString::number( rotationOffset ) );
 
   int nCats = qMin( categoryColors.size(), categoryAttributes.size() );
   for ( int i = 0; i < nCats; ++i )
@@ -447,8 +450,8 @@ void QgsDiagramRenderer::renderDiagram( const QgsFeature &feature, QgsRenderCont
     s.penColor = properties.valueAsColor( QgsDiagramLayerSettings::StrokeColor, c.expressionContext(), s.penColor );
     c.expressionContext().setOriginalValueVariable( s.penWidth );
     s.penWidth = properties.valueAsDouble( QgsDiagramLayerSettings::StrokeWidth, c.expressionContext(), s.penWidth );
-    c.expressionContext().setOriginalValueVariable( s.angleOffset / 16.0 );
+    c.expressionContext().setOriginalValueVariable( s.rotationOffset );
-    s.angleOffset = 16.0 * properties.valueAsDouble( QgsDiagramLayerSettings::StartAngle, c.expressionContext(), s.angleOffset / 16.0 );
+    s.rotationOffset = properties.valueAsDouble( QgsDiagramLayerSettings::StartAngle, c.expressionContext(), s.rotationOffset );
   }
 
   mDiagram->renderDiagram( feature, c, s, pos );

src/core/qgsdiagramrenderer.h

@@ -374,7 +374,7 @@ class CORE_EXPORT QgsDiagramSettings
       , barWidth( 5.0 )
       , opacity( 1.0 )
       , scaleByArea( true )
-      , angleOffset( 90 * 16 ) //top
+      , rotationOffset( 270 ) //top
       , scaleBasedVisibility( false )
       , minScaleDenominator( -1 )
       , maxScaleDenominator( -1 )
@@ -418,7 +418,12 @@ class CORE_EXPORT QgsDiagramSettings
     double opacity;
 
     bool scaleByArea;
-    int angleOffset;
+
+    /**
+     * Rotation offset, in degrees clockwise from horizontal.
+     * \since QGIS 3.0
+     */
+    double rotationOffset;
 
     bool scaleBasedVisibility;
     //scale range (-1 if no lower / upper bound )

src/core/qgsmapsettings.cpp

@@ -106,7 +106,8 @@ double QgsMapSettings::rotation() const
 
 void QgsMapSettings::setRotation( double degrees )
 {
-  if ( qgsDoubleNear( mRotation, degrees ) ) return;
+  if ( qgsDoubleNear( mRotation, degrees ) )
+    return;
 
   mRotation = degrees;
 

src/core/qgsmapsettings.h

@@ -76,14 +76,19 @@ class CORE_EXPORT QgsMapSettings
     //! Set the size of the resulting map image
     void setOutputSize( QSize size );
 
-    //! Return the rotation of the resulting map image
+    /**
-    //! Units are clockwise degrees
+     * Returns the rotation of the resulting map image, in degrees clockwise.
-    //! \since QGIS 2.8
+     * \since QGIS 2.8
+     * \see setRotation()
+     */
     double rotation() const;
-    //! Set the rotation of the resulting map image
+
-    //! Units are clockwise degrees
+    /**
-    //! \since QGIS 2.8
+     * Sets the \a rotation of the resulting map image, in degrees clockwise.
-    void setRotation( double degrees );
+     * \since QGIS 2.8
+     * \see rotation()
+     */
+    void setRotation( double rotation );
 
     //! Return DPI used for conversion between real world units (e.g. mm) and pixels
     //! Default value is 96

tests/src/core/testqgsdiagram.cpp

@@ -153,7 +153,7 @@ class TestQgsDiagram : public QObject
       ds.scaleByArea = true;
       ds.sizeType = QgsUnitTypes::RenderMillimeters;
       ds.size = QSizeF( 5, 5 );
-      ds.angleOffset = 0;
+      ds.rotationOffset = 270;
 
       QgsLinearlyInterpolatedDiagramRenderer *dr = new QgsLinearlyInterpolatedDiagramRenderer();
       dr->setLowerValue( 0.0 );
@@ -190,7 +190,7 @@ class TestQgsDiagram : public QObject
       ds.scaleByArea = true;
       ds.sizeType = QgsUnitTypes::RenderMillimeters;
       ds.size = QSizeF( 5, 5 );
-      ds.angleOffset = 0;
+      ds.rotationOffset = 270;
 
       QgsLinearlyInterpolatedDiagramRenderer *dr = new QgsLinearlyInterpolatedDiagramRenderer();
       dr->setLowerValue( 0.0 );
@@ -232,7 +232,7 @@ class TestQgsDiagram : public QObject
       ds.scaleByArea = true;
       ds.sizeType = QgsUnitTypes::RenderMillimeters;
       ds.size = QSizeF( 15, 15 );
-      ds.angleOffset = 0;
+      ds.rotationOffset = 270;
 
       QgsSingleCategoryDiagramRenderer *dr = new QgsSingleCategoryDiagramRenderer();
       dr->setDiagram( new QgsPieDiagram() );
@@ -269,7 +269,7 @@ class TestQgsDiagram : public QObject
       ds.scaleByArea = true;
       ds.sizeType = QgsUnitTypes::RenderMillimeters;
       ds.size = QSizeF( 15, 15 );
-      ds.angleOffset = 0;
+      ds.rotationOffset = 270;
 
       QgsSingleCategoryDiagramRenderer *dr = new QgsSingleCategoryDiagramRenderer();
       dr->setDiagram( new QgsPieDiagram() );
@@ -306,7 +306,7 @@ class TestQgsDiagram : public QObject
       ds.scaleByArea = true;
       ds.sizeType = QgsUnitTypes::RenderMillimeters;
       ds.size = QSizeF( 15, 15 );
-      ds.angleOffset = 0;
+      ds.rotationOffset = 270;
 
       QgsSingleCategoryDiagramRenderer *dr = new QgsSingleCategoryDiagramRenderer();
       dr->setDiagram( new QgsPieDiagram() );
@@ -342,7 +342,7 @@ class TestQgsDiagram : public QObject
       ds.scaleByArea = true;
       ds.sizeType = QgsUnitTypes::RenderMillimeters;
       ds.size = QSizeF( 15, 15 );
-      ds.angleOffset = 0;
+      ds.rotationOffset = 270;
 
       QgsSingleCategoryDiagramRenderer *dr = new QgsSingleCategoryDiagramRenderer();
       dr->setDiagram( new QgsPieDiagram() );
@@ -378,7 +378,7 @@ class TestQgsDiagram : public QObject
       ds.scaleByArea = true;
       ds.sizeType = QgsUnitTypes::RenderMillimeters;
       ds.size = QSizeF( 15, 15 );
-      ds.angleOffset = 0;
+      ds.rotationOffset = 270;
 
       QgsSingleCategoryDiagramRenderer *dr = new QgsSingleCategoryDiagramRenderer();
       dr->setDiagram( new QgsPieDiagram() );
@@ -414,7 +414,7 @@ class TestQgsDiagram : public QObject
       ds.scaleByArea = true;
       ds.sizeType = QgsUnitTypes::RenderMillimeters;
       ds.size = QSizeF( 50, 50 );
-      ds.angleOffset = 0;
+      ds.rotationOffset = 270;
 
       QgsSingleCategoryDiagramRenderer *dr = new QgsSingleCategoryDiagramRenderer();
       dr->setDiagram( new QgsPieDiagram() );
@@ -448,7 +448,7 @@ class TestQgsDiagram : public QObject
       ds.scaleByArea = true;
       ds.sizeType = QgsUnitTypes::RenderMillimeters;
       ds.size = QSizeF( 50, 50 );
-      ds.angleOffset = 0;
+      ds.rotationOffset = 270;
 
       QgsSingleCategoryDiagramRenderer *dr = new QgsSingleCategoryDiagramRenderer();
       dr->setDiagram( new QgsPieDiagram() );
@@ -484,7 +484,7 @@ class TestQgsDiagram : public QObject
       ds.scaleByArea = true;
       ds.sizeType = QgsUnitTypes::RenderMillimeters;
       ds.size = QSizeF( 50, 50 );
-      ds.angleOffset = 0;
+      ds.rotationOffset = 270;
 
       QgsSingleCategoryDiagramRenderer *dr = new QgsSingleCategoryDiagramRenderer();
       dr->setDiagram( new QgsPieDiagram() );
@@ -525,7 +525,7 @@ class TestQgsDiagram : public QObject
       ds.scaleByArea = true;
       ds.sizeType = QgsUnitTypes::RenderMillimeters;
       ds.size = QSizeF( 15, 15 );
-      ds.angleOffset = 0;
+      ds.rotationOffset = 270;
 
       QgsSingleCategoryDiagramRenderer *dr = new QgsSingleCategoryDiagramRenderer();
       dr->setDiagram( new QgsTextDiagram() );