[pal] Use GEOS methods for label position conflict tests

src/core/pal/costcalculator.cpp

@@ -42,6 +42,8 @@ namespace pal
         if ( dist < 0 )
           n = 2;
         else if ( dist < distlabel )
+          //note this never happens at the moment - points are not obstacles if they don't fall
+          //within the label
           n = 1;
         else
           n = 0;

src/core/pal/feature.cpp

@@ -1381,13 +1381,11 @@ namespace pal
       return false;
     }
 
-    if ( mOwnsGeom ) // delete old geometry if we own it
-      GEOSGeom_destroy_r( ctxt, mGeos );
-    GEOSPreparedGeom_destroy_r( ctxt, mPreparedGeom );
+    invalidateGeos();
+
     // set up new geometry
     mGeos = gTmp;
     mOwnsGeom = true;
-    mPreparedGeom = 0;
 
     deleteCoords();
     qDeleteAll( mHoles );

src/core/pal/labelposition.cpp

@@ -48,7 +48,8 @@
 namespace pal
 {
   LabelPosition::LabelPosition( int id, double x1, double y1, double w, double h, double alpha, double cost, FeaturePart *feature, bool isReversed, Quadrant quadrant )
-      : id( id )
+      : PointSet()
+      , id( id )
       , cost( cost )
       , feature( feature )
       , probFeat( 0 )
@@ -62,6 +63,10 @@ namespace pal
       , upsideDown( false )
       , quadrant( quadrant )
   {
+    type = GEOS_POLYGON;
+    nbPoints = 4;
+    x = new double[nbPoints];
+    y = new double[nbPoints];
 
     // alpha take his value bw 0 and 2*pi rad
     while ( this->alpha > 2*M_PI )
@@ -148,9 +153,18 @@ namespace pal
         upsideDown = true;
       }
     }
+
+    for ( int i = 0; i < nbPoints; ++i )
+    {
+      xmin = qMin( xmin, x[i] );
+      xmax = qMax( xmax, x[i] );
+      ymin = qMin( ymin, y[i] );
+      ymax = qMax( ymax, y[i] );
+    }
   }
 
   LabelPosition::LabelPosition( const LabelPosition& other )
+      : PointSet( other )
   {
     id = other.id;
     cost = other.cost;
@@ -250,39 +264,15 @@ namespace pal
 
   bool LabelPosition::isInConflictSinglePart( LabelPosition* lp )
   {
-    // TODO: add bounding box test to possibly avoid cross product calculation
+    if ( !mGeos )
+      createGeosGeom();
 
-    int i, i2, j;
-    int d1, d2;
-    double cp1, cp2;
+    if ( !lp->mGeos )
+      lp->createGeosGeom();
 
-    for ( i = 0; i < 4; i++ )
-    {
-      i2 = ( i + 1 ) % 4;
-      d1 = -1;
-      d2 = -1;
-
-      for ( j = 0; j < 4; j++ )
-      {
-        cp1 = cross_product( x[i], y[i], x[i2], y[i2], lp->x[j], lp->y[j] );
-        if ( cp1 > 0 )
-        {
-          d1 = 1;
-        }
-        cp2 = cross_product( lp->x[i], lp->y[i],
-                             lp->x[i2], lp->y[i2],
-                             x[j], y[j] );
-
-        if ( cp2 > 0 )
-        {
-          d2 = 1;
-        }
-      }
-
-      if ( d1 == -1 || d2 == -1 ) // disjoint
-        return false;
-    }
-    return true;
+    GEOSContextHandle_t geosctxt = geosContext();
+    bool result = ( GEOSPreparedIntersects_r( geosctxt, preparedGeom(), lp->mGeos ) == 1 );
+    return result;
   }
 
   bool LabelPosition::isInConflictMultiPart( LabelPosition* lp )
@@ -315,8 +305,9 @@ namespace pal
 
     if ( nextPart )
       nextPart->offsetPosition( xOffset, yOffset );
-  }
 
+    invalidateGeos();
+  }
 
   int LabelPosition::getId() const
   {
@@ -500,88 +491,35 @@ namespace pal
     return true;
   }
 
-
-
-  double LabelPosition::getDistanceToPoint( double xp, double yp )
+  double LabelPosition::getDistanceToPoint( double xp, double yp ) const
   {
-    int i;
-    int j;
+    //first check if inside, if so then distance is -1
+    double distance = ( containsPoint( xp, yp ) ? -1
+                        : sqrt( minDistanceToPoint( xp, yp ) ) );
 
-    double mx[4];
-    double my[4];
+    if ( nextPart && distance > 0 )
+      return qMin( distance, nextPart->getDistanceToPoint( xp, yp ) );
 
-    double dist_min = DBL_MAX;
-    double dist;
-
-    for ( i = 0; i < 4; i++ )
-    {
-      j = ( i + 1 ) % 4;
-      mx[i] = ( x[i] + x[j] ) / 2.0;
-      my[i] = ( y[i] + y[j] ) / 2.0;
+    return distance;
   }
 
-    if ( qAbs( cross_product( mx[0], my[0], mx[2], my[2], xp, yp ) / h ) < w / 2 )
+  bool LabelPosition::isBorderCrossingLine( PointSet* line ) const
   {
-      dist = cross_product( x[1], y[1], x[0], y[0], xp, yp ) / w;
-      if ( qAbs( dist ) < qAbs( dist_min ) )
-        dist_min = dist;
+    if ( !mGeos )
+      createGeosGeom();
 
-      dist = cross_product( x[3], y[3], x[2], y[2], xp, yp ) / w;
-      if ( qAbs( dist ) < qAbs( dist_min ) )
-        dist_min = dist;
-    }
+    if ( !line->mGeos )
+      line->createGeosGeom();
 
-    if ( qAbs( cross_product( mx[1], my[1], mx[3], my[3], xp, yp ) / w ) < h / 2 )
+    GEOSContextHandle_t geosctxt = geosContext();
+    if ( GEOSPreparedIntersects_r( geosctxt, preparedGeom(), line->mGeos ) == 1 )
     {
-      dist = cross_product( x[2], y[2], x[1], y[1], xp, yp ) / h;
-      if ( qAbs( dist ) < qAbs( dist_min ) )
-        dist_min = dist;
-
-      dist = cross_product( x[0], y[0], x[3], y[3], xp, yp ) / h;
-      if ( qAbs( dist ) < qAbs( dist_min ) )
-        dist_min = dist;
-    }
-
-    for ( i = 0; i < 4; i++ )
-    {
-      dist = dist_euc2d( x[i], y[i], xp, yp );
-      if ( qAbs( dist ) < qAbs( dist_min ) )
-        dist_min = dist;
-    }
-
-    if ( nextPart && dist_min > 0 )
-      return qMin( dist_min, nextPart->getDistanceToPoint( xp, yp ) );
-
-    return dist_min;
-  }
-
-
-  bool LabelPosition::isBorderCrossingLine( PointSet* feat )
-  {
-    double ca, cb;
-    for ( int i = 0; i < 4; i++ )
-    {
-      for ( int j = 0; j < feat->getNumPoints() - 1; j++ )
-      {
-        ca = cross_product( x[i], y[i], x[( i+1 ) %4], y[( i+1 ) %4],
-                            feat->x[j], feat->y[j] );
-        cb = cross_product( x[i], y[i], x[( i+1 ) %4], y[( i+1 ) %4],
-                            feat->x[j+1], feat->y[j+1] );
-
-        if (( ca < 0 && cb > 0 ) || ( ca > 0 && cb < 0 ) )
-        {
-          ca = cross_product( feat->x[j], feat->y[j], feat->x[j+1], feat->y[j+1],
-                              x[i], y[i] );
-          cb = cross_product( feat->x[j], feat->y[j], feat->x[j+1], feat->y[j+1],
-                              x[( i+1 ) %4], y[( i+1 ) %4] );
-          if (( ca < 0 && cb > 0 ) || ( ca > 0 && cb < 0 ) )
       return true;
     }
+    else if ( nextPart )
+    {
+      return nextPart->isBorderCrossingLine( line );
     }
-    }
-
-    if ( nextPart )
-      return nextPart->isBorderCrossingLine( feat );
 
     return false;
   }

src/core/pal/labelposition.h

@@ -45,7 +45,7 @@ namespace pal
   /**
    * \brief LabelPosition is a candidate feature label position
    */
-  class CORE_EXPORT LabelPosition
+  class CORE_EXPORT LabelPosition : public PointSet
   {
       friend class CostCalculator;
       friend class PolygonCostCalculator;
@@ -126,10 +126,10 @@ namespace pal
       void getBoundingBox( double amin[2], double amax[2] ) const;
 
       /** Get distance from this label to a point. If point lies inside, returns negative number. */
-      double getDistanceToPoint( double xp, double yp );
+      double getDistanceToPoint( double xp, double yp ) const;
 
       /** Returns true if this label crosses the specified line */
-      bool isBorderCrossingLine( PointSet* feat );
+      bool isBorderCrossingLine( PointSet* line ) const;
 
       /** Returns number of intersections with polygon (testing border and center) */
       int getNumPointsInPolygon( PointSet* polygon ) const;
@@ -258,7 +258,6 @@ namespace pal
 
       int nbOverlap;
 
-      double x[4], y[4];
       double alpha;
       double w;
       double h;

src/core/pal/pointset.cpp

@@ -109,7 +109,7 @@ namespace pal
     type = GEOS_POINT;
   }
 
-  PointSet::PointSet( PointSet &ps )
+  PointSet::PointSet( const PointSet &ps )
       : mGeos( 0 )
       , mOwnsGeom( false )
       , parent( 0 )
@@ -211,6 +211,17 @@ namespace pal
     return mPreparedGeom;
   }
 
+  void PointSet::invalidateGeos()
+  {
+    GEOSContextHandle_t geosctxt = geosContext();
+    if ( mOwnsGeom ) // delete old geometry if we own it
+      GEOSGeom_destroy_r( geosctxt, mGeos );
+    GEOSPreparedGeom_destroy_r( geosctxt, mPreparedGeom );
+    mOwnsGeom = false;
+    mGeos = 0;
+    mPreparedGeom = 0;
+  }
+
   PointSet::~PointSet()
   {
     GEOSContextHandle_t geosctxt = geosContext();
@@ -867,7 +878,7 @@ namespace pal
     return finalBb;
   }
 
-  double PointSet::minDistanceToPoint( double px, double py, double *rx, double *ry )
+  double PointSet::minDistanceToPoint( double px, double py, double *rx, double *ry ) const
   {
     if ( !mGeos )
       createGeosGeom();

src/core/pal/pointset.h

@@ -98,7 +98,7 @@ namespace pal
                                  QLinkedList<PointSet *> &shapes_final,
                                  double xrm, double yrm, const QString &uid );
 
-      /** Returns the minimum distance between the point set geometry and the point (px,py)
+      /** Returns the squared minimum distance between the point set geometry and the point (px,py)
        * Optionally, the nearest point is stored in (rx,ry).
        * @param px x coordinate of the point
        * @param py y coordinate of the points
@@ -106,7 +106,7 @@ namespace pal
        * @param ry pointer to y coorinates of the nearest point (can be NULL)
        * @returns minimum distance
        */
-      double minDistanceToPoint( double px, double py, double *rx = 0, double *ry = 0 );
+      double minDistanceToPoint( double px, double py, double *rx = 0, double *ry = 0 ) const;
 
       void getCentroid( double &px, double &py, bool forceInside = false ) const;
 
@@ -156,11 +156,12 @@ namespace pal
 
       PointSet( double x, double y );
 
-      PointSet( PointSet &ps );
+      PointSet( const PointSet &ps );
 
       void deleteCoords();
       void createGeosGeom() const;
       const GEOSPreparedGeometry* preparedGeom() const;
+      void invalidateGeos();
 
       double xmin;
       double xmax;