Merge pull request #1338 from manisandro/line_multi_labeling

Line multi labeling

src/app/qgslabelinggui.cpp

@@ -62,6 +62,7 @@ QgsLabelingGui::QgsLabelingGui( QgsVectorLayer* layer, QgsMapCanvas* mapCanvas,
   mShadowRadiusUnitWidget->setUnits( QStringList() << tr( "mm" ) << tr( "map units" ), 1 );
   mPointOffsetUnitWidget->setUnits( QStringList() << tr( "mm" ) << tr( "map units" ), 1 );
   mLineDistanceUnitWidget->setUnits( QStringList() << tr( "mm" ) << tr( "map units" ), 1 );
+  mRepeatDistanceUnitWidget->setUnits( QStringList() << tr( "mm" ) << tr( "map units" ), 1 );
 
   mCharDlg = new QgsCharacterSelectorDialog( this );
 
@@ -308,6 +309,11 @@ void QgsLabelingGui::init()
       chkLineOrientationDependent->setChecked( true );
   }
 
+  // Label repeat distance
+  mRepeatDistanceSpinBox->setValue( lyr.repeatDistance );
+  mRepeatDistanceUnitWidget->setUnit( lyr.repeatDistanceUnit - 1 );
+  mRepeatDistanceUnitWidget->setMapUnitScale( lyr.repeatDistanceMapUnitScale );
+
   mPrioritySlider->setValue( lyr.priority );
   chkNoObstacle->setChecked( lyr.obstacle );
   chkLabelPerFeaturePart->setChecked( lyr.labelPerPart );
@@ -591,6 +597,9 @@ QgsPalLayerSettings QgsLabelingGui::layerSettings()
     qFatal( "Invalid settings" );
   }
 
+  lyr.repeatDistance = mRepeatDistanceSpinBox->value();
+  lyr.repeatDistanceUnit = static_cast<QgsPalLayerSettings::SizeUnit>(1 + mRepeatDistanceUnitWidget->getUnit());
+  lyr.repeatDistanceMapUnitScale = mRepeatDistanceUnitWidget->getMapUnitScale();
 
   lyr.textColor = btnTextColor->color();
   lyr.textFont = mRefFont;
@@ -779,6 +788,8 @@ QgsPalLayerSettings QgsLabelingGui::layerSettings()
   // TODO: is this necessary? maybe just use the data defined-only rotation?
   //setDataDefinedProperty( mPointAngleDDBtn, QgsPalLayerSettings::OffsetRotation, lyr );
   setDataDefinedProperty( mMaxCharAngleDDBtn, QgsPalLayerSettings::CurvedCharAngleInOut, lyr );
+  setDataDefinedProperty( mRepeatDistanceDDBtn, QgsPalLayerSettings::RepeatDistance, lyr );
+  setDataDefinedProperty( mRepeatDistanceUnitDDBtn, QgsPalLayerSettings::RepeatDistanceUnit, lyr );
 
   // data defined-only
   setDataDefinedProperty( mCoordXDDBtn, QgsPalLayerSettings::PositionX, lyr );
@@ -1004,6 +1015,10 @@ void QgsLabelingGui::populateDataDefinedButtons( QgsPalLayerSettings& s )
   //                        QgsDataDefinedButton::AnyType, QgsDataDefinedButton::double180RotDesc() );
   mMaxCharAngleDDBtn->init( mLayer, s.dataDefinedProperty( QgsPalLayerSettings::CurvedCharAngleInOut ),
                             QgsDataDefinedButton::AnyType, tr( "double coord [<b>in,out</b> as 20.0-60.0,20.0-95.0]" ) );
+  mRepeatDistanceDDBtn->init( mLayer, s.dataDefinedProperty( QgsPalLayerSettings::RepeatDistance ),
+                              QgsDataDefinedButton::AnyType, QgsDataDefinedButton::doublePosDesc() );
+  mRepeatDistanceUnitDDBtn->init( mLayer, s.dataDefinedProperty( QgsPalLayerSettings::DistanceUnits ),
+                                QgsDataDefinedButton::String, QgsDataDefinedButton::unitsMmMuDesc() );
 
   // data defined-only
   QString ddPlaceInfo = tr( "In edit mode, layer's relevant labeling map tool is:<br>"

src/core/pal/layer.cpp

@@ -39,6 +39,7 @@
 #include <iostream>
 #include <cstring>
 #include <cmath>
+#include <vector>
 
 
 #include <pal/pal.h>
@@ -228,7 +229,7 @@ namespace pal
 
   bool Layer::registerFeature( const char *geom_id, PalGeometry *userGeom, double label_x, double label_y, const char* labelText,
                                double labelPosX, double labelPosY, bool fixedPos, double angle, bool fixedAngle,
-                               int xQuadOffset, int yQuadOffset, double xOffset, double yOffset, bool alwaysShow )
+                               int xQuadOffset, int yQuadOffset, double xOffset, double yOffset, bool alwaysShow, double repeatDistance )
   {
     if ( !geom_id || label_x < 0 || label_y < 0 )
       return false;
@@ -284,6 +285,74 @@ namespace pal
       throw InternalException::UnknownGeometry();
     }
 
+    // if multiple labels are requested for lines, split the line in pieces of desired distance
+    if(repeatDistance > 0) {
+      int nSimpleGeometries = simpleGeometries->size();
+      for(int i = 0; i < nSimpleGeometries; ++i) {
+        const GEOSGeometry* geom = simpleGeometries->pop_front();
+        if(GEOSGeomTypeId(geom) == GEOS_LINESTRING) {
+
+          // get number of points
+          int n = GEOSGeomGetNumPoints(geom);
+
+          // Read points
+          std::vector<Point> points(n);
+          for(int i = 0; i < n; ++i) {
+            GEOSGeometry* p = GEOSGeomGetPointN(geom, i);
+            GEOSGeomGetX(p, &points[i].x);
+            GEOSGeomGetY(p, &points[i].y);
+            GEOSGeom_destroy(p);
+          }
+
+          // Cumulative length vector
+          std::vector<double> len(n, 0);
+          for(int i = 1; i < n; ++i) {
+            double dx = points[i].x - points[i - 1].x;
+            double dy = points[i].y - points[i - 1].y;
+            len[i] = len[i - 1] + std::sqrt(dx * dx + dy * dy);
+          }
+
+          // Walk along line
+          int cur = 0;
+          double lambda = 0;
+          std::vector<Point> part;
+          while(true) {
+            lambda += repeatDistance;
+            for(; cur < n && lambda > len[cur]; ++cur) {
+              part.push_back(points[cur]);
+            }
+            if(cur >= n) {
+              break;
+            }
+            double c = (lambda - len[cur - 1]) / (len[cur] - len[cur - 1]);
+            Point p;
+            p.x = points[cur - 1].x + c * (points[cur].x - points[cur - 1].x);
+            p.y = points[cur - 1].y + c * (points[cur].y - points[cur - 1].y);
+            part.push_back(p);
+            GEOSCoordSequence* cooSeq = GEOSCoordSeq_create(part.size(), 2);
+            for(std::size_t i = 0; i < part.size(); ++i) {
+              GEOSCoordSeq_setX(cooSeq, i, part[i].x);
+              GEOSCoordSeq_setY(cooSeq, i, part[i].y);
+            }
+
+            simpleGeometries->push_back(GEOSGeom_createLineString(cooSeq));
+            part.clear();
+            part.push_back(p);
+          }
+          // Create final part
+          part.push_back(points[n - 1]);
+          GEOSCoordSequence* cooSeq = GEOSCoordSeq_create(part.size(), 2);
+          for(std::size_t i = 0; i < part.size(); ++i) {
+            GEOSCoordSeq_setX(cooSeq, i, part[i].x);
+            GEOSCoordSeq_setY(cooSeq, i, part[i].y);
+          }
+          simpleGeometries->push_back(GEOSGeom_createLineString(cooSeq));
+        }else{
+          simpleGeometries->push_back( geom );
+        }
+      }
+    }
+
     while ( simpleGeometries->size() > 0 )
     {
       const GEOSGeometry* geom = simpleGeometries->pop_front();
@@ -320,7 +389,7 @@ namespace pal
         continue;
       }
 
-      if ( mode == LabelPerFeature && ( type == GEOS_POLYGON || type == GEOS_LINESTRING ) )
+      if ( mode == LabelPerFeature && repeatDistance == 0.0 && ( type == GEOS_POLYGON || type == GEOS_LINESTRING ) )
       {
         if ( type == GEOS_LINESTRING )
           GEOSLength( geom, &geom_size );
@@ -349,7 +418,7 @@ namespace pal
     modMutex->unlock();
 
     // if using only biggest parts...
-    if (( mode == LabelPerFeature || f->fixedPosition() ) && biggest_part != NULL )
+    if (( (mode == LabelPerFeature && repeatDistance == 0.0) || f->fixedPosition() ) && biggest_part != NULL )
     {
       addFeaturePart( biggest_part, labelText );
       first_feat = false;

src/core/pal/layer.h

@@ -317,7 +317,7 @@ namespace pal
                             const char* labelText = NULL, double labelPosX = 0.0, double labelPosY = 0.0,
                             bool fixedPos = false, double angle = 0.0, bool fixedAngle = false,
                             int xQuadOffset = 0, int yQuadOffset = 0, double xOffset = 0.0, double yOffset = 0.0,
-                            bool alwaysShow = false );
+                            bool alwaysShow = false, double repeatDistance = 0.0 );
 
       /** return pointer to feature or NULL if doesn't exist */
       Feature* getFeature( const char* geom_id );

src/core/pal/util.h

@@ -74,6 +74,10 @@ namespace pal
     int  new_label;
   } ElemTrans;
 
+  struct Point {
+    double x, y;
+  };
+
 
 
 #define EPSILON 1e-9

src/core/qgspallabeling.cpp

@@ -322,6 +322,8 @@ QgsPalLayerSettings::QgsPalLayerSettings()
   maxCurvedCharAngleIn = 20.0;
   maxCurvedCharAngleOut = -20.0;
   priority = 5;
+  repeatDistance = 0;
+  repeatDistanceUnit = MM;
 
   // rendering
   scaleVisibility = false;
@@ -513,6 +515,9 @@ QgsPalLayerSettings::QgsPalLayerSettings( const QgsPalLayerSettings& s )
   maxCurvedCharAngleIn = s.maxCurvedCharAngleIn;
   maxCurvedCharAngleOut = s.maxCurvedCharAngleOut;
   priority = s.priority;
+  repeatDistance = s.repeatDistance;
+  repeatDistanceUnit = s.repeatDistanceUnit;
+  repeatDistanceMapUnitScale = s.repeatDistanceMapUnitScale;
 
   // rendering
   scaleVisibility = s.scaleVisibility;
@@ -1007,6 +1012,10 @@ void QgsPalLayerSettings::readFromLayer( QgsVectorLayer* layer )
   maxCurvedCharAngleIn = layer->customProperty( "labeling/maxCurvedCharAngleIn", QVariant( 20.0 ) ).toDouble();
   maxCurvedCharAngleOut = layer->customProperty( "labeling/maxCurvedCharAngleOut", QVariant( -20.0 ) ).toDouble();
   priority = layer->customProperty( "labeling/priority" ).toInt();
+  repeatDistance = layer->customProperty( "labeling/repeatDistance", 0.0 ).toDouble();
+  repeatDistanceUnit = (SizeUnit) layer->customProperty( "labeling/repeatDistanceUnit", QVariant( MM )).toUInt();
+  repeatDistanceMapUnitScale.minScale = layer->customProperty( "labeling/repeatDistanceMapUnitMinScale", 0.0).toDouble();
+  repeatDistanceMapUnitScale.maxScale = layer->customProperty( "labeling/repeatDistanceMapUnitMaxScale", 0.0).toDouble();
 
   // rendering
   int scalemn = layer->customProperty( "labeling/scaleMin", QVariant( 0 ) ).toInt();
@@ -1173,6 +1182,10 @@ void QgsPalLayerSettings::writeToLayer( QgsVectorLayer* layer )
   layer->setCustomProperty( "labeling/maxCurvedCharAngleIn", maxCurvedCharAngleIn );
   layer->setCustomProperty( "labeling/maxCurvedCharAngleOut", maxCurvedCharAngleOut );
   layer->setCustomProperty( "labeling/priority", priority );
+  layer->setCustomProperty( "labeling/repeatDistance", repeatDistance );
+  layer->setCustomProperty( "labeling/repeatDistanceUnit", repeatDistanceUnit );
+  layer->setCustomProperty( "labeling/repeatDistanceMapUnitMinScale", repeatDistanceMapUnitScale.minScale );
+  layer->setCustomProperty( "labeling/repeatDistanceMapUnitMaxScale", repeatDistanceMapUnitScale.maxScale );
 
   // rendering
   layer->setCustomProperty( "labeling/scaleVisibility", scaleVisibility );
@@ -2219,12 +2232,48 @@ void QgsPalLayerSettings::registerFeature( QgsFeature& f, const QgsRenderContext
 #endif
   lbl->setDefinedFont( labelFont );
 
+  // data defined repeat distance?
+  double repeatDist = repeatDistance;
+  if ( dataDefinedEvaluate( QgsPalLayerSettings::RepeatDistance, exprVal ) )
+  {
+    bool ok;
+    double distD = exprVal.toDouble( &ok );
+    if ( ok )
+    {
+      repeatDist = distD;
+    }
+  }
+
+  // data defined label-repeat distance units?
+  bool repeatdistinmapunit = repeatDistanceUnit == MapUnits;
+  if ( dataDefinedEvaluate( QgsPalLayerSettings::RepeatDistanceUnit, exprVal ) )
+  {
+    QString units = exprVal.toString().trimmed();
+    QgsDebugMsgLevel( QString( "exprVal RepeatDistanceUnits:%1" ).arg( units ), 4 );
+    if ( !units.isEmpty() )
+    {
+      repeatdistinmapunit = ( _decodeUnits( units ) == QgsPalLayerSettings::MapUnits );
+    }
+  }
+
+  if ( repeatDist != 0 )
+  {
+    if ( !repeatdistinmapunit ) //convert distance from mm/map units to pixels
+    {
+      repeatDist *= repeatDistanceMapUnitScale.computeMapUnitsPerPixel(context) * context.scaleFactor();
+    }
+    else //mm
+    {
+      repeatDist *= vectorScaleFactor;
+    }
+  }
+
   //  feature to the layer
   try
   {
     if ( !palLayer->registerFeature( lbl->strId(), lbl, labelX, labelY, labelText.toUtf8().constData(),
                                      xPos, yPos, dataDefinedPosition, angle, dataDefinedRotation,
-                                     quadOffsetX, quadOffsetY, offsetX, offsetY, alwaysShow ) )
+                                     quadOffsetX, quadOffsetY, offsetX, offsetY, alwaysShow, repeatDist ) )
       return;
   }
   catch ( std::exception &e )
@@ -2279,6 +2328,7 @@ void QgsPalLayerSettings::registerFeature( QgsFeature& f, const QgsRenderContext
     feat->setDistLabel( qAbs( ptOne.x() - ptZero.x() )* distance );
   }
 
+
   //add parameters for data defined labeling to QgsPalGeometry
   QMap< DataDefinedProperties, QVariant >::const_iterator dIt = dataDefinedValues.constBegin();
   for ( ; dIt != dataDefinedValues.constEnd(); ++dIt )

src/core/qgspallabeling.h

@@ -254,6 +254,8 @@ class CORE_EXPORT QgsPalLayerSettings
       Hali = 11, //horizontal alignment for data defined label position (Left, Center, Right)
       Vali = 12, //vertical alignment for data defined label position (Bottom, Base, Half, Cap, Top)
       Rotation = 14, //data defined rotation
+      RepeatDistance = 84,
+      RepeatDistanceUnit = 85,
 
       // rendering
       ScaleVisibility = 23,
@@ -377,6 +379,10 @@ class CORE_EXPORT QgsPalLayerSettings
     bool distInMapUnits; //true if distance is in map units (otherwise in mm)
     QgsMapUnitScale distMapUnitScale;
 
+    double repeatDistance;
+    SizeUnit repeatDistanceUnit;
+    QgsMapUnitScale repeatDistanceMapUnitScale;
+
     // offset labels of point/centroid features default to center
     // move label to quadrant: left/down, don't move, right/up (-1, 0, 1)
     QuadrantPosition quadOffset;