GRASS topology layers - display internal topo info

src/plugins/grass/qgsgrassplugin.cpp

@@ -321,11 +321,14 @@ void QgsGrassPlugin::addVector()
     QString field;
     QString type;
 
-    QRegExp rx( "(\\d+)_(.+)" );
-    if ( rx.indexIn( sel->layer ) != -1 )
+    if ( !sel->layer.startsWith( "topo_" ) )
     {
-      field = rx.cap( 1 );
-      type = rx.cap( 2 );
+      QRegExp rx( "(\\d+)_(.+)" );
+      if ( rx.indexIn( sel->layer ) != -1 )
+      {
+        field = rx.cap( 1 );
+        type = rx.cap( 2 );
+      }
     }
 
     // Set location
@@ -355,26 +358,33 @@ void QgsGrassPlugin::addVector()
 
       if ( level >= 2 )
       {
-        // Count layers
-        int cnt = 0;
-        int ncidx = Vect_cidx_get_num_fields( &map );
-
-        for ( int i = 0; i < ncidx; i++ )
+        if ( !sel->layer.startsWith( "topo_" ) )
         {
-          int field = Vect_cidx_get_field_number( &map, i );
+          // Count layers
+          int cnt = 0;
+          int ncidx = Vect_cidx_get_num_fields( &map );
 
-          if ( Vect_cidx_get_type_count( &map, field, GV_POINT | GV_LINE | GV_AREA ) > 0 ||
-               ( field > 1 && Vect_cidx_get_type_count( &map, field, GV_BOUNDARY ) ) )
+          for ( int i = 0; i < ncidx; i++ )
           {
-            cnt++;
+            int field = Vect_cidx_get_field_number( &map, i );
+
+            if ( Vect_cidx_get_type_count( &map, field, GV_POINT | GV_LINE | GV_AREA ) > 0 ||
+                 ( field > 1 && Vect_cidx_get_type_count( &map, field, GV_BOUNDARY ) ) )
+            {
+              cnt++;
+            }
           }
-        }
 
-        if ( cnt > 1 )
-        {
-          name.append( " " + field );
+          if ( cnt > 1 )
+          {
+            name.append( " " + field );
 
-          // No need to ad type, the type is obvious from the legend
+            // No need to ad type, the type is obvious from the legend
+          }
+        }
+        else
+        {
+          name.append( " " + sel->layer );
         }
       }
 

src/providers/grass/qgsgrass.cpp

@@ -877,6 +877,21 @@ QStringList GRASS_LIB_EXPORT QgsGrass::vectorLayers( QString gisdbase,
       list.append( l );
     }
   }
+
+  // add topology layers
+  if ( Vect_get_num_primitives( &map, GV_POINTS ) > 0 )
+  {
+    list.append( "topo_point" );
+  }
+  if ( Vect_get_num_primitives( &map, GV_LINES ) > 0 )
+  {
+    list.append( "topo_line" );
+  }
+  if ( Vect_get_num_nodes( &map ) > 0 )
+  {
+    list.append( "topo_node" );
+  }
+
   Vect_close( &map );
 
   return list;

src/providers/grass/qgsgrassfeatureiterator.cpp

@@ -71,23 +71,28 @@ void QgsGrassFeatureIterator::setSelectionRect( const QgsRectangle& rect, bool u
   //apply selection rectangle
   resetSelection( 0 );
 
+  BOUND_BOX box;
+  box.N = rect.yMaximum(); box.S = rect.yMinimum();
+  box.E = rect.xMaximum(); box.W = rect.xMinimum();
+  box.T = PORT_DOUBLE_MAX; box.B = -PORT_DOUBLE_MAX;
+
   if ( !useIntersect )
   { // select by bounding boxes only
-    BOUND_BOX box;
-    box.N = rect.yMaximum(); box.S = rect.yMinimum();
-    box.E = rect.xMaximum(); box.W = rect.xMinimum();
-    box.T = PORT_DOUBLE_MAX; box.B = -PORT_DOUBLE_MAX;
     if ( P->mLayerType == QgsGrassProvider::POINT || P->mLayerType == QgsGrassProvider::CENTROID ||
          P->mLayerType == QgsGrassProvider::LINE || P->mLayerType == QgsGrassProvider::FACE ||
-         P->mLayerType == QgsGrassProvider::BOUNDARY )
+         P->mLayerType == QgsGrassProvider::BOUNDARY ||
+         P->mLayerType == QgsGrassProvider::TOPO_POINT || P->mLayerType == QgsGrassProvider::TOPO_LINE )
     {
       Vect_select_lines_by_box( P->mMap, &box, P->mGrassType, mList );
     }
     else if ( P->mLayerType == QgsGrassProvider::POLYGON )
     {
       Vect_select_areas_by_box( P->mMap, &box, mList );
     }
-
+    else if ( P->mLayerType == QgsGrassProvider::TOPO_NODE )
+    {
+      Vect_select_nodes_by_box( P->mMap, &box, mList );
+    }
   }
   else
   { // check intersection
@@ -106,14 +111,20 @@ void QgsGrassFeatureIterator::setSelectionRect( const QgsRectangle& rect, bool u
 
     if ( P->mLayerType == QgsGrassProvider::POINT || P->mLayerType == QgsGrassProvider::CENTROID ||
          P->mLayerType == QgsGrassProvider::LINE || P->mLayerType == QgsGrassProvider::FACE ||
-         P->mLayerType == QgsGrassProvider::BOUNDARY )
+         P->mLayerType == QgsGrassProvider::BOUNDARY ||
+         P->mLayerType == QgsGrassProvider::TOPO_POINT || P->mLayerType == QgsGrassProvider::TOPO_LINE )
     {
       Vect_select_lines_by_polygon( P->mMap, Polygon, 0, NULL, P->mGrassType, mList );
     }
     else if ( P->mLayerType == QgsGrassProvider::POLYGON )
     {
       Vect_select_areas_by_polygon( P->mMap, Polygon, 0, NULL, mList );
     }
+    else if ( P->mLayerType == QgsGrassProvider::TOPO_NODE )
+    {
+      // There is no Vect_select_nodes_by_polygon but for nodes it is the same as by box
+      Vect_select_nodes_by_box( P->mMap, &box, mList );
+    }
 
     Vect_destroy_line_struct( Polygon );
   }
@@ -153,7 +164,8 @@ bool QgsGrassFeatureIterator::nextFeature( QgsFeature& feature )
     return false;
   }
 
-  if ( P->mCidxFieldIndex < 0 || mNextCidx >= P->mCidxFieldNumCats )
+  // TODO: is this necessary? the same is checked below
+  if ( !P->isTopoType()  && ( P->mCidxFieldIndex < 0 || mNextCidx >= P->mCidxFieldNumCats ) )
   {
     close();
     return false; // No features, no features in this layer
@@ -163,17 +175,39 @@ bool QgsGrassFeatureIterator::nextFeature( QgsFeature& feature )
 
   // Get next line/area id
   int found = 0;
-  while ( mNextCidx < P->mCidxFieldNumCats )
+  while ( true )
   {
-    Vect_cidx_get_cat_by_index( P->mMap, P->mCidxFieldIndex, mNextCidx++, &cat, &type, &id );
-    // Warning: selection array is only of type line/area of current layer -> check type first
-    if ( !( type & P->mGrassType ) )
-      continue;
+    QgsDebugMsgLevel( QString( "mNextTopoId = %1" ).arg( mNextTopoId ), 3 );
+    if ( P->mLayerType == QgsGrassProvider::TOPO_POINT || P->mLayerType == QgsGrassProvider::TOPO_LINE )
+    {
+      if ( mNextTopoId > Vect_get_num_lines( P->mMap ) ) break;
+      id = mNextTopoId;
+      type = Vect_read_line( P->mMap, 0, 0, mNextTopoId++ );
+      if ( !( type & P->mGrassType ) ) continue;
+      featureId = id;
+    }
+    else if ( P->mLayerType == QgsGrassProvider::TOPO_NODE )
+    {
+      if ( mNextTopoId > Vect_get_num_nodes( P->mMap ) ) break;
+      id = mNextTopoId;
+      type = 0;
+      mNextTopoId++;
+      featureId = id;
+    }
+    else
+    {
+      if ( mNextCidx >= P->mCidxFieldNumCats ) break;
 
-    // The 'id' is a unique id of a GRASS geometry object (point, line, area)
-    // but it cannot be used as QgsFeatureId because one geometry object may
-    // represent more features because it may have more categories.
-    featureId = makeFeatureId( id, cat );
+      Vect_cidx_get_cat_by_index( P->mMap, P->mCidxFieldIndex, mNextCidx++, &cat, &type, &id );
+      // Warning: selection array is only of type line/area of current layer -> check type first
+      if ( !( type & P->mGrassType ) )
+        continue;
+
+      // The 'id' is a unique id of a GRASS geometry object (point, line, area)
+      // but it cannot be used as QgsFeatureId because one geometry object may
+      // represent more features because it may have more categories.
+      featureId = makeFeatureId( id, cat );
+    }
 
     if ( filterById && featureId != mRequest.filterFid() )
       continue;
@@ -202,10 +236,52 @@ bool QgsGrassFeatureIterator::nextFeature( QgsFeature& feature )
   else
     setFeatureGeometry( feature, id, type );
 
-  if ( mRequest.flags() & QgsFeatureRequest::SubsetOfAttributes )
-    P->setFeatureAttributes( P->mLayerId, cat, &feature, mRequest.subsetOfAttributes() );
+  if ( ! P->isTopoType() )
+  {
+    if ( mRequest.flags() & QgsFeatureRequest::SubsetOfAttributes )
+      P->setFeatureAttributes( P->mLayerId, cat, &feature, mRequest.subsetOfAttributes() );
+    else
+      P->setFeatureAttributes( P->mLayerId, cat, &feature );
+  }
   else
-    P->setFeatureAttributes( P->mLayerId, cat, &feature );
+  {
+    feature.setAttribute( 0, id );
+    if ( P->mLayerType == QgsGrassProvider::TOPO_POINT || P->mLayerType == QgsGrassProvider::TOPO_LINE )
+    {
+      feature.setAttribute( 1, P->primitiveTypeName( type ) );
+
+      int node1, node2;
+      Vect_get_line_nodes( P->mMap, id, &node1, &node2 );
+      feature.setAttribute( 2, node1 );
+      if ( P->mLayerType == QgsGrassProvider::TOPO_LINE )
+      {
+        feature.setAttribute( 3, node2 );
+      }
+    }
+
+    if ( P->mLayerType == QgsGrassProvider::TOPO_LINE )
+    {
+      if ( type == GV_BOUNDARY )
+      {
+        int left, right;
+        Vect_get_line_areas( P->mMap, id, &left, &right );
+        feature.setAttribute( 4, left );
+        feature.setAttribute( 5, right );
+      }
+    }
+    else if ( P->mLayerType == QgsGrassProvider::TOPO_NODE )
+    {
+      QString lines;
+      int nlines = Vect_get_node_n_lines( P->mMap, id );
+      for ( int i = 0; i < nlines; i++ )
+      {
+        int line = Vect_get_node_line( P->mMap, id, i );
+        if ( i > 0 ) lines += ",";
+        lines += QString::number( line );
+      }
+      feature.setAttribute( 1, lines );
+    }
+  }
 
   feature.setValid( true );
 
@@ -227,6 +303,7 @@ bool QgsGrassFeatureIterator::rewind()
   P->ensureUpdated();
 
   mNextCidx = 0;
+  mNextTopoId = 1;
 
   return true;
 }
@@ -258,6 +335,7 @@ void QgsGrassFeatureIterator::resetSelection( bool sel )
   QgsDebugMsg( "entered." );
   memset( mSelection, ( int ) sel, mSelectionSize );
   mNextCidx = 0;
+  mNextTopoId = 1;
 }
 
 
@@ -291,12 +369,26 @@ void QgsGrassFeatureIterator::setFeatureGeometry( QgsFeature& feature, int id, i
   int wkbsize;
 
   // TODO int may be 64 bits (memcpy)
-  if ( type & ( GV_POINTS | GV_LINES | GV_FACE ) ) /* points or lines */
+  if ( type & ( GV_POINTS | GV_LINES | GV_FACE ) || P->mLayerType == QgsGrassProvider::TOPO_NODE ) /* points or lines */
   {
-    Vect_read_line( P->mMap, mPoints, mCats, id );
+    if ( P->mLayerType == QgsGrassProvider::TOPO_NODE )
+    {
+      double x, y, z;
+      Vect_get_node_coor( P->mMap, id, &x, &y, &z );
+      Vect_reset_line( mPoints );
+      Vect_append_point( mPoints, x, y, z );
+    }
+    else
+    {
+      Vect_read_line( P->mMap, mPoints, 0, id );
+    }
     int npoints = mPoints->n_points;
 
-    if ( type & GV_POINTS )
+    if ( P->mLayerType == QgsGrassProvider::TOPO_NODE )
+    {
+      wkbsize = 1 + 4 + 2 * 8;
+    }
+    else if ( type & GV_POINTS )
     {
       wkbsize = 1 + 4 + 2 * 8;
     }

src/providers/grass/qgsgrassfeatureiterator.h

@@ -60,7 +60,9 @@ class QgsGrassFeatureIterator : public QgsAbstractFeatureIterator
     char    *mSelection;           // !UPDATE!
     int     mSelectionSize;        // !UPDATE! Size of selection array
 
+    // Either mNextCidx or mNextTopoId is used according to type
     int    mNextCidx;          // !UPDATE! Next index in cidxFieldIndex to be read, used to find nextFeature
+    int    mNextTopoId;          // !UPDATE! Next topology id to be read, used to find nextFeature, starts from 1
 
     /*! reset selection */
     void resetSelection( bool sel );