Fix line dependent orientation rendering of curved labels

Fixes #45051
qgis · Feb 2, 2022 · e3909cb · e3909cb
1 parent 13d8468
commit e3909cb
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Showing 6 changed files with 152 additions and 11 deletions.
diff --git a/src/core/pal/feature.cpp b/src/core/pal/feature.cpp
@@ -1337,12 +1337,16 @@ std::size_t FeaturePart::createCurvedCandidatesAlongLine( std::vector< std::uniq
   if ( hasAboveBelowLinePlacement && !qgsDoubleNear( offsetDistance, 0 ) )
   {
     // create offseted map shapes to be used for above and below line placements
-    mapShapeOffsetPositive = mapShape->clone();
-    mapShapeOffsetNegative = mapShape->clone();
-    if ( offsetDistance >= 0.0 )
+    if ( ( flags & QgsLabeling::LinePlacementFlag::MapOrientation ) || ( flags & QgsLabeling::LinePlacementFlag::AboveLine ) )
+      mapShapeOffsetPositive = mapShape->clone();
+    if ( ( flags & QgsLabeling::LinePlacementFlag::MapOrientation ) || ( flags & QgsLabeling::LinePlacementFlag::BelowLine ) )
+      mapShapeOffsetNegative = mapShape->clone();
+    if ( offsetDistance >= 0.0 || !( flags & QgsLabeling::LinePlacementFlag::MapOrientation ) )
     {
-      mapShapeOffsetPositive->offsetCurveByDistance( offsetDistance );
-      mapShapeOffsetNegative->offsetCurveByDistance( offsetDistance * -1 );
+      if ( mapShapeOffsetPositive )
+        mapShapeOffsetPositive->offsetCurveByDistance( offsetDistance );
+      if ( mapShapeOffsetNegative )
+        mapShapeOffsetNegative->offsetCurveByDistance( offsetDistance * -1 );
     }
     else
     {
@@ -1359,8 +1363,10 @@ std::size_t FeaturePart::createCurvedCandidatesAlongLine( std::vector< std::uniq
         flags &= ~QgsLabeling::LinePlacementFlag::BelowLine;
         flags |= QgsLabeling::LinePlacementFlag::AboveLine;
       }
-      mapShapeOffsetPositive->offsetCurveByDistance( offsetDistance * -1 );
-      mapShapeOffsetNegative->offsetCurveByDistance( offsetDistance );
+      if ( mapShapeOffsetPositive )
+        mapShapeOffsetPositive->offsetCurveByDistance( offsetDistance * -1 );
+      if ( mapShapeOffsetNegative )
+        mapShapeOffsetNegative->offsetCurveByDistance( offsetDistance );
     }
   }
 
@@ -1422,10 +1428,13 @@ std::size_t FeaturePart::createCurvedCandidatesAlongLine( std::vector< std::uniq
 
       if ( !labelPosition )
         continue;
-      if ( ( offset != NoOffset ) && !labeledLineSegmentIsRightToLeft && !( flags & QgsLabeling::LinePlacementFlag::AboveLine ) )
-        continue;
-      if ( ( offset != NoOffset ) && labeledLineSegmentIsRightToLeft && !( flags & QgsLabeling::LinePlacementFlag::BelowLine ) )
-        continue;
+      if ( flags & QgsLabeling::LinePlacementFlag::MapOrientation )
+      {
+        if ( ( offset != NoOffset ) && !labeledLineSegmentIsRightToLeft && !( flags & QgsLabeling::LinePlacementFlag::AboveLine ) )
+          continue;
+        if ( ( offset != NoOffset ) && labeledLineSegmentIsRightToLeft && !( flags & QgsLabeling::LinePlacementFlag::BelowLine ) )
+          continue;
+      }
 
       // evaluate cost
       const double angleDiff = labelPosition->angleDifferential();

diff --git a/tests/src/core/testqgslabelingengine.cpp b/tests/src/core/testqgslabelingengine.cpp
@@ -72,6 +72,8 @@ class TestQgsLabelingEngine : public QObject
     void testCurvedLabelCorrectLinePlacement();
     void testCurvedLabelNegativeDistance();
     void testCurvedLabelOnSmallLineNearCenter();
+    void testCurvedLabelLineOrientationAbove();
+    void testCurvedLabelLineOrientationBelow();
     void testRepeatDistanceWithSmallLine();
     void testParallelPlacementPreferAbove();
     void testLabelBoundary();
@@ -1535,6 +1537,136 @@ void TestQgsLabelingEngine::testCurvedLabelOnSmallLineNearCenter()
   QVERIFY( imageCheck( QStringLiteral( "label_curved_small_feature_centered" ), img, 20 ) );
 }
 
+void TestQgsLabelingEngine::testCurvedLabelLineOrientationAbove()
+{
+  QgsPalLayerSettings settings;
+  setDefaultLabelParams( settings );
+
+  QgsTextFormat format = settings.format();
+  format.setSize( 20 );
+  format.setColor( QColor( 0, 0, 0 ) );
+  settings.setFormat( format );
+
+  settings.fieldName = QStringLiteral( "'XXXXXXXX'" );
+  settings.isExpression = true;
+  settings.placement = QgsPalLayerSettings::Curved;
+  settings.labelPerPart = false;
+  settings.lineSettings().setPlacementFlags( QgsLabeling::LinePlacementFlag::AboveLine );
+
+  std::unique_ptr< QgsVectorLayer> vl2( new QgsVectorLayer( QStringLiteral( "LineString?crs=epsg:3946&field=id:integer" ), QStringLiteral( "vl" ), QStringLiteral( "memory" ) ) );
+  vl2->setRenderer( new QgsSingleSymbolRenderer( QgsLineSymbol::createSimple( { {QStringLiteral( "color" ), QStringLiteral( "#000000" )}, {QStringLiteral( "outline_width" ), 0.6} } ) ) );
+
+  QgsFeature f;
+  f.setAttributes( QgsAttributes() << 1 );
+  f.setGeometry( QgsGeometry::fromWkt( QStringLiteral( "LineString (190100 5000007, 190094 5000012, 190096 5000019, 190103 5000024, 190111 5000023, 190114 5000018)" ) ) );
+  QVERIFY( vl2->dataProvider()->addFeature( f ) );
+
+  vl2->setLabeling( new QgsVectorLayerSimpleLabeling( settings ) );  // TODO: this should not be necessary!
+  vl2->setLabelsEnabled( true );
+
+  // make a fake render context
+  const QSize size( 640, 480 );
+  QgsMapSettings mapSettings;
+  mapSettings.setLabelingEngineSettings( createLabelEngineSettings() );
+  mapSettings.setDestinationCrs( vl2->crs() );
+
+  mapSettings.setOutputSize( size );
+  mapSettings.setExtent( QgsRectangle( 190080, 5000000, 190130, 5000030 ) );
+  mapSettings.setLayers( QList<QgsMapLayer *>() << vl2.get() );
+  mapSettings.setOutputDpi( 96 );
+
+  QgsLabelingEngineSettings engineSettings = mapSettings.labelingEngineSettings();
+  engineSettings.setFlag( QgsLabelingEngineSettings::UsePartialCandidates, false );
+  engineSettings.setFlag( QgsLabelingEngineSettings::DrawLabelRectOnly, true );
+  //engineSettings.setFlag( QgsLabelingEngineSettings::DrawCandidates, true );
+  mapSettings.setLabelingEngineSettings( engineSettings );
+
+  QgsMapRendererSequentialJob job( mapSettings );
+  job.start();
+  job.waitForFinished();
+
+  QImage img = job.renderedImage();
+  QVERIFY( imageCheck( QStringLiteral( "label_curved_line_orientation_above" ), img, 20 ) );
+
+  // reverse line and retry, label should be flipped to other side of line
+  f.setGeometry( QgsGeometry( qgsgeometry_cast< QgsLineString * >( f.geometry().constGet() )->reversed() ) );
+  vl2->dataProvider()->truncate();
+  QVERIFY( vl2->dataProvider()->addFeature( f ) );
+
+
+  QgsMapRendererSequentialJob job2( mapSettings );
+  job2.start();
+  job2.waitForFinished();
+
+  img = job2.renderedImage();
+  QVERIFY( imageCheck( QStringLiteral( "label_curved_line_orientation_reversed_above" ), img, 20 ) );
+}
+
+void TestQgsLabelingEngine::testCurvedLabelLineOrientationBelow()
+{
+  QgsPalLayerSettings settings;
+  setDefaultLabelParams( settings );
+
+  QgsTextFormat format = settings.format();
+  format.setSize( 20 );
+  format.setColor( QColor( 0, 0, 0 ) );
+  settings.setFormat( format );
+
+  settings.fieldName = QStringLiteral( "'XXXXXXXX'" );
+  settings.isExpression = true;
+  settings.placement = QgsPalLayerSettings::Curved;
+  settings.labelPerPart = false;
+  settings.lineSettings().setPlacementFlags( QgsLabeling::LinePlacementFlag::BelowLine );
+
+  std::unique_ptr< QgsVectorLayer> vl2( new QgsVectorLayer( QStringLiteral( "LineString?crs=epsg:3946&field=id:integer" ), QStringLiteral( "vl" ), QStringLiteral( "memory" ) ) );
+  vl2->setRenderer( new QgsSingleSymbolRenderer( QgsLineSymbol::createSimple( { {QStringLiteral( "color" ), QStringLiteral( "#000000" )}, {QStringLiteral( "outline_width" ), 0.6} } ) ) );
+
+  QgsFeature f;
+  f.setAttributes( QgsAttributes() << 1 );
+  f.setGeometry( QgsGeometry::fromWkt( QStringLiteral( "LineString (190100 5000007, 190094 5000012, 190096 5000019, 190103 5000024, 190111 5000023, 190114 5000018)" ) ) );
+  QVERIFY( vl2->dataProvider()->addFeature( f ) );
+
+  vl2->setLabeling( new QgsVectorLayerSimpleLabeling( settings ) );  // TODO: this should not be necessary!
+  vl2->setLabelsEnabled( true );
+
+  // make a fake render context
+  const QSize size( 640, 480 );
+  QgsMapSettings mapSettings;
+  mapSettings.setLabelingEngineSettings( createLabelEngineSettings() );
+  mapSettings.setDestinationCrs( vl2->crs() );
+
+  mapSettings.setOutputSize( size );
+  mapSettings.setExtent( QgsRectangle( 190080, 5000000, 190130, 5000030 ) );
+  mapSettings.setLayers( QList<QgsMapLayer *>() << vl2.get() );
+  mapSettings.setOutputDpi( 96 );
+
+  QgsLabelingEngineSettings engineSettings = mapSettings.labelingEngineSettings();
+  engineSettings.setFlag( QgsLabelingEngineSettings::UsePartialCandidates, false );
+  engineSettings.setFlag( QgsLabelingEngineSettings::DrawLabelRectOnly, true );
+  //engineSettings.setFlag( QgsLabelingEngineSettings::DrawCandidates, true );
+  mapSettings.setLabelingEngineSettings( engineSettings );
+
+  QgsMapRendererSequentialJob job( mapSettings );
+  job.start();
+  job.waitForFinished();
+
+  QImage img = job.renderedImage();
+  QVERIFY( imageCheck( QStringLiteral( "label_curved_line_orientation_below" ), img, 20 ) );
+
+  // reverse line and retry, label should be flipped to other side of line
+  f.setGeometry( QgsGeometry( qgsgeometry_cast< QgsLineString * >( f.geometry().constGet() )->reversed() ) );
+  vl2->dataProvider()->truncate();
+  QVERIFY( vl2->dataProvider()->addFeature( f ) );
+
+
+  QgsMapRendererSequentialJob job2( mapSettings );
+  job2.start();
+  job2.waitForFinished();
+
+  img = job2.renderedImage();
+  QVERIFY( imageCheck( QStringLiteral( "label_curved_line_orientation_reversed_below" ), img, 20 ) );
+}
+
 void TestQgsLabelingEngine::testRepeatDistanceWithSmallLine()
 {
   // test a small line relative to label size still gives sufficient candidates to ensure more centered placements

diff --git a/..._curved_line_orientation_above/expected_label_curved_line_orientation_above.png b/..._curved_line_orientation_above/expected_label_curved_line_orientation_above.png
diff --git a/..._curved_line_orientation_below/expected_label_curved_line_orientation_below.png b/..._curved_line_orientation_below/expected_label_curved_line_orientation_below.png
diff --git a/...tation_reversed_above/expected_label_curved_line_orientation_reversed_above.png b/...tation_reversed_above/expected_label_curved_line_orientation_reversed_above.png
diff --git a/...tation_reversed_below/expected_label_curved_line_orientation_reversed_below.png b/...tation_reversed_below/expected_label_curved_line_orientation_reversed_below.png