Fix confusion in angle handling for label results, where angles

in radians were being treated as degrees

This made an interactive movement of a label shown for a line
segment initially have a quasi-random rotation, instead of
keeping the rotation of the original label

src/app/labeling/qgsmaptoollabel.cpp

@@ -660,7 +660,7 @@ bool QgsMapToolLabel::currentLabelRotationPoint( QgsPointXY &pos, bool ignoreUps
       break;
   }
 
-  double angle = mCurrentLabel.pos.rotation;
+  double angle = mCurrentLabel.pos.rotation * M_PI / 180;
   double xd = xdiff * std::cos( angle ) - ydiff * std::sin( angle );
   double yd = xdiff * std::sin( angle ) + ydiff * std::cos( angle );
   if ( mCurrentLabel.pos.upsideDown && !ignoreUpsideDown )

src/app/labeling/qgsmaptoolmovelabel.cpp

@@ -617,7 +617,7 @@ void QgsMapToolMoveLabel::cadCanvasPressEvent( QgsMapMouseEvent *e )
             int rCol;
             if ( currentLabelDataDefinedRotation( defRot, rSuccess, rCol ) )
             {
-              const double labelRot = mCurrentLabel.pos.rotation * 180 / M_PI;
+              const double labelRot = mCurrentLabel.pos.rotation;
               vlayer->changeAttributeValue( mCurrentLabel.pos.featureId, rCol, labelRot );
             }
           }

src/app/labeling/qgsmaptoolpinlabels.cpp

@@ -389,7 +389,7 @@ bool QgsMapToolPinLabels::pinUnpinCurrentLabel( bool pin )
 
     double labelX = referencePoint.x();
     double labelY = referencePoint.y();
-    double labelR = labelpos.rotation * 180 / M_PI;
+    double labelR = labelpos.rotation;
 
     // transform back to layer crs
     QgsPointXY transformedPoint = mCanvas->mapSettings().mapToLayerCoordinates( vlayer, referencePoint );

src/core/labeling/qgslabelfeature.h

@@ -107,7 +107,11 @@ class CORE_EXPORT QgsLabelFeature
     //TODO - remove when QgsGeometry caches GEOS preparedness
     const GEOSPreparedGeometry *permissibleZonePrepared() const { return mPermissibleZoneGeosPrepared.get(); }
 
-    //! Size of the label (in map units)
+    /**
+     * Size of the label (in map units).
+     *
+     * An optional \a angle (in radians) can be specified to return the size taking into account the rotation.
+     */
     QSizeF size( double angle = 0.0 ) const;
 
     /**
@@ -227,9 +231,17 @@ class CORE_EXPORT QgsLabelFeature
     bool hasFixedAngle() const { return mHasFixedAngle; }
     //! Sets whether the label should use a fixed angle instead of using angle from automatic placement
     void setHasFixedAngle( bool enabled ) { mHasFixedAngle = enabled; }
-    //! Angle in degrees of the fixed angle (relevant only if hasFixedAngle() returns TRUE)
+
+    /**
+     * Angle in radians of the fixed angle (relevant only if hasFixedAngle() returns TRUE)
+     * \see setFixedAngle()
+     */
     double fixedAngle() const { return mFixedAngle; }
-    //! Sets angle in degrees of the fixed angle (relevant only if hasFixedAngle() returns TRUE)
+
+    /**
+     * Sets the \a angle in radians of the fixed angle (relevant only if hasFixedAngle() returns TRUE).
+     * \see fixedAngle()
+     */
     void setFixedAngle( double angle ) { mFixedAngle = angle; }
 
     /**

src/core/labeling/qgslabelsearchtree.cpp

@@ -106,7 +106,7 @@ bool QgsLabelSearchTree::insertLabel( pal::LabelPosition *labelPos, QgsFeatureId
 
   const QgsRectangle bounds( xMin, yMin, xMax, yMax );
   const QgsGeometry labelGeometry( QgsGeometry::fromPolygonXY( QVector<QgsPolylineXY>() << cornerPoints ) );
-  std::unique_ptr< QgsLabelPosition > newEntry = std::make_unique< QgsLabelPosition >( featureId, labelPos->getAlpha() + mMapSettings.rotation(), cornerPoints, bounds,
+  std::unique_ptr< QgsLabelPosition > newEntry = std::make_unique< QgsLabelPosition >( featureId, -labelPos->getAlpha() * 180 / M_PI + mMapSettings.rotation(), cornerPoints, bounds,
       labelPos->getWidth(), labelPos->getHeight(), layerName, labeltext, labelfont, labelPos->getUpsideDown(), diagram, pinned, providerId, labelGeometry, isUnplaced );
   newEntry->groupedLabelId = uniqueLinkedId;
   mSpatialIndex.insert( newEntry.get(), bounds );

src/core/labeling/qgspallabeling.cpp

@@ -2344,7 +2344,8 @@ std::unique_ptr<QgsLabelFeature> QgsPalLayerSettings::registerFeatureWithDetails
   //data defined position / alignment / rotation?
   bool layerDefinedRotation = false;
   bool dataDefinedRotation = false;
-  double xPos = 0.0, yPos = 0.0, angle = 0.0;
+  double xPos = 0.0, yPos = 0.0;
+  double angleInRadians = 0.0;
   double quadOffsetX = 0.0, quadOffsetY = 0.0;
   double offsetX = 0.0, offsetY = 0.0;
   QgsPointXY anchorPosition;
@@ -2461,7 +2462,7 @@ std::unique_ptr<QgsLabelFeature> QgsPalLayerSettings::registerFeatureWithDetails
   if ( !qgsDoubleNear( angleOffset, 0.0 ) )
   {
     layerDefinedRotation = true;
-    angle = ( 360 - angleOffset ) * M_PI / 180; // convert to radians counterclockwise
+    angleInRadians = ( 360 - angleOffset ) * M_PI / 180; // convert to radians counterclockwise
   }
 
   const QgsMapToPixel &m2p = context.mapToPixel();
@@ -2484,7 +2485,7 @@ std::unique_ptr<QgsLabelFeature> QgsPalLayerSettings::registerFeatureWithDetails
         // TODO: add setting to disable having data defined rotation follow
         //       map rotation ?
         rotationDegrees += m2p.mapRotation();
-        angle = ( 360 - rotationDegrees ) * M_PI / 180.0;
+        angleInRadians = ( 360 - rotationDegrees ) * M_PI / 180.0;
       }
     }
   }
@@ -2550,7 +2551,7 @@ std::unique_ptr<QgsLabelFeature> QgsPalLayerSettings::registerFeatureWithDetails
         // layer rotation set, but don't rotate pinned labels unless data defined
         if ( layerDefinedRotation && !dataDefinedRotation )
         {
-          angle = 0.0;
+          angleInRadians = 0.0;
         }
 
         //horizontal alignment
@@ -2608,8 +2609,8 @@ std::unique_ptr<QgsLabelFeature> QgsPalLayerSettings::registerFeatureWithDetails
         if ( dataDefinedRotation )
         {
           //adjust xdiff and ydiff because the hali/vali point needs to be the rotation center
-          double xd = xdiff * std::cos( angle ) - ydiff * std::sin( angle );
-          double yd = xdiff * std::sin( angle ) + ydiff * std::cos( angle );
+          double xd = xdiff * std::cos( angleInRadians ) - ydiff * std::sin( angleInRadians );
+          double yd = xdiff * std::sin( angleInRadians ) + ydiff * std::cos( angleInRadians );
           xdiff = xd;
           ydiff = yd;
         }
@@ -2725,8 +2726,8 @@ std::unique_ptr<QgsLabelFeature> QgsPalLayerSettings::registerFeatureWithDetails
   labelFeature->setHasFixedPosition( hasDataDefinedPosition );
   labelFeature->setFixedPosition( QgsPointXY( xPos, yPos ) );
   // use layer-level defined rotation, but not if position fixed
-  labelFeature->setHasFixedAngle( dataDefinedRotation || ( !hasDataDefinedPosition && !qgsDoubleNear( angle, 0.0 ) ) );
-  labelFeature->setFixedAngle( angle );
+  labelFeature->setHasFixedAngle( dataDefinedRotation || ( !hasDataDefinedPosition && !qgsDoubleNear( angleInRadians, 0.0 ) ) );
+  labelFeature->setFixedAngle( angleInRadians );
   labelFeature->setQuadOffset( QPointF( quadOffsetX, quadOffsetY ) );
   labelFeature->setPositionOffset( QgsPointXY( offsetX, offsetY ) );
   labelFeature->setOffsetType( offsetType );

src/core/pal/feature.cpp

@@ -2146,23 +2146,23 @@ std::size_t FeaturePart::createCandidatesOutsidePolygon( std::vector<std::unique
 std::vector< std::unique_ptr< LabelPosition > > FeaturePart::createCandidates( Pal *pal )
 {
   std::vector< std::unique_ptr< LabelPosition > > lPos;
-  double angle = mLF->hasFixedAngle() ? mLF->fixedAngle() : 0.0;
+  double angleInRadians = mLF->hasFixedAngle() ? mLF->fixedAngle() : 0.0;
 
   if ( mLF->hasFixedPosition() )
   {
-    lPos.emplace_back( std::make_unique< LabelPosition> ( 0, mLF->fixedPosition().x(), mLF->fixedPosition().y(), getLabelWidth( angle ), getLabelHeight( angle ), angle, 0.0, this, false, LabelPosition::Quadrant::QuadrantOver ) );
+    lPos.emplace_back( std::make_unique< LabelPosition> ( 0, mLF->fixedPosition().x(), mLF->fixedPosition().y(), getLabelWidth( angleInRadians ), getLabelHeight( angleInRadians ), angleInRadians, 0.0, this, false, LabelPosition::Quadrant::QuadrantOver ) );
   }
   else
   {
     switch ( type )
     {
       case GEOS_POINT:
         if ( mLF->layer()->arrangement() == Qgis::LabelPlacement::OrderedPositionsAroundPoint )
-          createCandidatesAtOrderedPositionsOverPoint( x[0], y[0], lPos, angle );
+          createCandidatesAtOrderedPositionsOverPoint( x[0], y[0], lPos, angleInRadians );
         else if ( mLF->layer()->arrangement() == Qgis::LabelPlacement::OverPoint || mLF->hasFixedQuadrant() )
-          createCandidatesOverPoint( x[0], y[0], lPos, angle );
+          createCandidatesOverPoint( x[0], y[0], lPos, angleInRadians );
         else
-          createCandidatesAroundPoint( x[0], y[0], lPos, angle );
+          createCandidatesAroundPoint( x[0], y[0], lPos, angleInRadians );
         break;
 
       case GEOS_LINESTRING:
@@ -2206,15 +2206,15 @@ std::vector< std::unique_ptr< LabelPosition > > FeaturePart::createCandidates( P
                 double cx, cy;
                 getCentroid( cx, cy, mLF->layer()->centroidInside() );
                 if ( qgsDoubleNear( mLF->distLabel(), 0.0 ) )
-                  created += createCandidateCenteredOverPoint( cx, cy, lPos, angle );
-                created += createCandidatesAroundPoint( cx, cy, lPos, angle );
+                  created += createCandidateCenteredOverPoint( cx, cy, lPos, angleInRadians );
+                created += createCandidatesAroundPoint( cx, cy, lPos, angleInRadians );
                 break;
               }
               case Qgis::LabelPlacement::OverPoint:
               {
                 double cx, cy;
                 getCentroid( cx, cy, mLF->layer()->centroidInside() );
-                created += createCandidatesOverPoint( cx, cy, lPos, angle );
+                created += createCandidatesOverPoint( cx, cy, lPos, angleInRadians );
                 break;
               }
               case Qgis::LabelPlacement::Line:

src/core/pal/feature.h

@@ -263,14 +263,12 @@ namespace pal
       bool hasSameLabelFeatureAs( FeaturePart *part ) const;
 
       /**
-       * Returns the width of the label, optionally taking an \a angle into account.
-       * \returns the width of the label
+       * Returns the width of the label, optionally taking an \a angle (in radians) into account.
        */
       double getLabelWidth( double angle = 0.0 ) const { return mLF->size( angle ).width(); }
 
       /**
-       * Returns the height of the label, optionally taking an \a angle into account.
-       * \returns the hieght of the label
+       * Returns the height of the label, optionally taking an \a angle (in radians) into account.
        */
       double getLabelHeight( double angle = 0.0 ) const { return mLF->size( angle ).height(); }
 

src/core/pal/labelposition.h

@@ -83,7 +83,7 @@ namespace pal
        * \param y1 down-left y coordinate
        * \param w label width
        * \param h label height
-       * \param alpha rotation in rad
+       * \param alpha rotation in radians
        * \param cost geographic cost
        * \param feature labelpos owners
        * \param isReversed label is reversed
@@ -270,9 +270,10 @@ namespace pal
       double getHeight() const { return h; }
 
       /**
-       * Returns the angle to rotate text (in rad).
+       * Returns the angle to rotate text (in radians).
        */
       double getAlpha() const;
+
       bool getReversed() const { return reversed; }
       bool getUpsideDown() const { return upsideDown; }
 
@@ -368,7 +369,9 @@ namespace pal
 
       int nbOverlap;
 
+      //! Rotation in radians
       double alpha;
+
       double w;
       double h;
 

tests/src/core/testqgslabelingengine.cpp

@@ -3801,6 +3801,7 @@ void TestQgsLabelingEngine::labelingResults()
   settings.isExpression = true;
   settings.placement = Qgis::LabelPlacement::OverPoint;
   settings.priority = 10;
+  settings.angleOffset = 3;
 
   std::unique_ptr< QgsVectorLayer> vl2( new QgsVectorLayer( QStringLiteral( "Point?crs=epsg:4326&field=id:integer" ), QStringLiteral( "vl" ), QStringLiteral( "memory" ) ) );
   vl2->setRenderer( new QgsNullSymbolRenderer() );
@@ -3865,11 +3866,11 @@ void TestQgsLabelingEngine::labelingResults()
   QCOMPARE( labels.at( 0 ).labelText, QStringLiteral( "1" ) );
   QGSCOMPARENEAR( labels.at( 0 ).width, 167961, 500 ); // tolerance will probably need tweaking, to account for cross-platform font diffs
   QGSCOMPARENEAR( labels.at( 0 ).height, 295119, 500 );
-  QGSCOMPARENEAR( labels.at( 0 ).labelRect.xMinimum(), -779822, 500 );
-  QGSCOMPARENEAR( labels.at( 0 ).labelRect.xMaximum(), -611861, 500 );
-  QGSCOMPARENEAR( labels.at( 0 ).labelRect.yMinimum(), 6897647, 500 );
-  QGSCOMPARENEAR( labels.at( 0 ).labelRect.yMaximum(), 7192767, 500 );
-  QCOMPARE( labels.at( 0 ).rotation, 0.0 );
+  QGSCOMPARENEAR( labels.at( 0 ).labelRect.xMinimum(), -787429, 500 );
+  QGSCOMPARENEAR( labels.at( 0 ).labelRect.xMaximum(), -604253, 500 );
+  QGSCOMPARENEAR( labels.at( 0 ).labelRect.yMinimum(), 6893454, 500 );
+  QGSCOMPARENEAR( labels.at( 0 ).labelRect.yMaximum(), 7196960, 500 );
+  QCOMPARE( labels.at( 0 ).rotation, -357 );
 
   labels = results->labelsAtPosition( QgsPointXY( -769822, 6927647 ) );
   QCOMPARE( labels.count(), 1 );
@@ -3884,22 +3885,22 @@ void TestQgsLabelingEngine::labelingResults()
   QCOMPARE( labels.at( 0 ).labelText, QStringLiteral( "8888" ) );
   QGSCOMPARENEAR( labels.at( 0 ).width, 671844, 500 ); // tolerance will probably need tweaking, to account for cross-platform font diffs
   QGSCOMPARENEAR( labels.at( 0 ).height, 295119, 500 );
-  QGSCOMPARENEAR( labels.at( 0 ).labelRect.xMinimum(), -2779386, 500 );
-  QGSCOMPARENEAR( labels.at( 0 ).labelRect.xMaximum(), -2107542, 500 );
-  QGSCOMPARENEAR( labels.at( 0 ).labelRect.yMinimum(), 9240403, 500 );
-  QGSCOMPARENEAR( labels.at( 0 ).labelRect.yMaximum(), 9535523, 500 );
-  QCOMPARE( labels.at( 0 ).rotation, 0.0 );
+  QGSCOMPARENEAR( labels.at( 0 ).labelRect.xMinimum(), -2786649, 500 );
+  QGSCOMPARENEAR( labels.at( 0 ).labelRect.xMaximum(), -2100279, 500 );
+  QGSCOMPARENEAR( labels.at( 0 ).labelRect.yMinimum(), 9223025, 500 );
+  QGSCOMPARENEAR( labels.at( 0 ).labelRect.yMaximum(), 9552902, 500 );
+  QCOMPARE( labels.at( 0 ).rotation, -357 );
   labels = results->labelsAtPosition( QgsPointXY( -1383, 6708478 ) );
   QCOMPARE( labels.count(), 1 );
   QCOMPARE( labels.at( 0 ).featureId, 3 );
   QCOMPARE( labels.at( 0 ).labelText, QStringLiteral( "33333" ) );
   QGSCOMPARENEAR( labels.at( 0 ).width, 839805, 500 ); // tolerance will probably need tweaking, to account for cross-platform font diffs
   QGSCOMPARENEAR( labels.at( 0 ).height, 295119, 500 );
-  QGSCOMPARENEAR( labels.at( 0 ).labelRect.xMinimum(), -433112, 500 );
-  QGSCOMPARENEAR( labels.at( 0 ).labelRect.xMaximum(), 406692, 500 );
-  QGSCOMPARENEAR( labels.at( 0 ).labelRect.yMinimum(), 6563006, 500 );
-  QGSCOMPARENEAR( labels.at( 0 ).labelRect.yMaximum(), 6858125, 500 );
-  QCOMPARE( labels.at( 0 ).rotation, 0.0 );
+  QGSCOMPARENEAR( labels.at( 0 ).labelRect.xMinimum(), -440260, 500 );
+  QGSCOMPARENEAR( labels.at( 0 ).labelRect.xMaximum(), 413840, 500 );
+  QGSCOMPARENEAR( labels.at( 0 ).labelRect.yMinimum(), 6541232, 500 );
+  QGSCOMPARENEAR( labels.at( 0 ).labelRect.yMaximum(), 6879899, 500 );
+  QCOMPARE( labels.at( 0 ).rotation, -357 );
   labels = results->labelsAtPosition( QgsPointXY( -2463392, 6708478 ) );
   QCOMPARE( labels.count(), 0 );
 
@@ -3938,7 +3939,10 @@ void TestQgsLabelingEngine::labelingResults()
 
   mapSettings.setLayers( {vl2.get() } );
 
-  // with rotation
+  // with map rotation
+  settings.angleOffset = 0;
+  vl2->setLabeling( new QgsVectorLayerSimpleLabeling( settings ) );  // TODO: this should not be necessary!
+  vl2->setLabelsEnabled( true );
   mapSettings.setRotation( 60 );
   QgsMapRendererSequentialJob job2( mapSettings );
   job2.start();