_lwt_HealEdges()

static LWT_ELEMID _lwt_HealEdges ( LWT_TOPOLOGY *  topo, LWT_ELEMID  eid1, LWT_ELEMID  eid2, int  modEdge  )

static

Definition at line 4186 of file lwgeom_topo.c.

{
  LWT_ELEMID ids[2];
  LWT_ELEMID commonnode = -1;
  int caseno = 0;
  LWT_ISO_EDGE *node_edges;
  int num_node_edges;
  LWT_ISO_EDGE *edges;
  LWT_ISO_EDGE *e1 = NULL;
  LWT_ISO_EDGE *e2 = NULL;
  LWT_ISO_EDGE newedge, updedge, seledge;
  int nedges, i;
  int e1freenode;
  int e2sign, e2freenode;
  POINTARRAY *pa;
  char buf[256];
  char *ptr;
  size_t bufleft = 256;
 
  ptr = buf;
 
  /* NOT IN THE SPECS: see if the same edge is given twice.. */
  if ( eid1 == eid2 )
  {
    lwerror("Cannot heal edge %" LWTFMT_ELEMID
            " with itself, try with another", eid1);
    return -1;
  }
  ids[0] = eid1;
  ids[1] = eid2;
  nedges = 2;
  edges = lwt_be_getEdgeById(topo, ids, &nedges, LWT_COL_EDGE_ALL);
  if ((nedges == -1) || (edges == NULL))
  {
    lwerror("Backend error: %s", lwt_be_lastErrorMessage(topo->be_iface));
    return -1;
  }
  for ( i=0; i<nedges; ++i )
  {
    if ( edges[i].edge_id == eid1 ) {
      if ( e1 ) {
        _lwt_release_edges(edges, nedges);
        lwerror("Corrupted topology: multiple edges have id %"
                LWTFMT_ELEMID, eid1);
        return -1;
      }
      e1 = &(edges[i]);
    }
    else if ( edges[i].edge_id == eid2 ) {
      if ( e2 ) {
        _lwt_release_edges(edges, nedges);
        lwerror("Corrupted topology: multiple edges have id %"
                LWTFMT_ELEMID, eid2);
        return -1;
      }
      e2 = &(edges[i]);
    }
  }
  if ( ! e1 )
  {
          _lwt_release_edges(edges, nedges);
          lwerror(
              "SQL/MM Spatial exception - non-existent edge %" LWTFMT_ELEMID,
              eid1);
          return -1;
  }
  if ( ! e2 )
  {
          _lwt_release_edges(edges, nedges);
          lwerror(
              "SQL/MM Spatial exception - non-existent edge %" LWTFMT_ELEMID,
              eid2);
          return -1;
  }
 
  /* NOT IN THE SPECS: See if any of the two edges are closed. */
  if ( e1->start_node == e1->end_node )
  {
    _lwt_release_edges(edges, nedges);
    lwerror("Edge %" LWTFMT_ELEMID " is closed, cannot heal to edge %"
            LWTFMT_ELEMID, eid1, eid2);
    return -1;
  }
  if ( e2->start_node == e2->end_node )
  {
    _lwt_release_edges(edges, nedges);
    lwerror("Edge %" LWTFMT_ELEMID " is closed, cannot heal to edge %"
            LWTFMT_ELEMID, eid2, eid1);
    return -1;
  }
 
  /* Find common node */
 
  if ( e1->end_node == e2->start_node )
  {
    commonnode = e1->end_node;
    caseno = 1;
  }
  else if ( e1->end_node == e2->end_node )
  {
    commonnode = e1->end_node;
    caseno = 2;
  }
  /* Check if any other edge is connected to the common node, if found */
  if ( commonnode != -1 )
  {
    num_node_edges = 1;
    node_edges = lwt_be_getEdgeByNode( topo, &commonnode,
                                       &num_node_edges, LWT_COL_EDGE_EDGE_ID );
    if ( num_node_edges == -1 ) {
      _lwt_release_edges(edges, nedges);
      lwerror("Backend error: %s", lwt_be_lastErrorMessage(topo->be_iface));
      return -1;
    }
    for (i=0; i<num_node_edges; ++i)
    {
      int r;
      if ( node_edges[i].edge_id == eid1 ) continue;
      if ( node_edges[i].edge_id == eid2 ) continue;
      commonnode = -1;
      /* append to string, for error message */
      if ( bufleft > 0 ) {
        r = snprintf(ptr, bufleft, "%s%" LWTFMT_ELEMID,
                     ( ptr==buf ? "" : "," ), node_edges[i].edge_id);
        if ( r >= (int) bufleft )
        {
          bufleft = 0;
          buf[252] = '.';
          buf[253] = '.';
          buf[254] = '.';
          buf[255] = '\0';
        }
        else
        {
          bufleft -= r;
          ptr += r;
        }
      }
    }
    lwfree(node_edges);
  }
 
  if ( commonnode == -1 )
  {
    if ( e1->start_node == e2->start_node )
    {
      commonnode = e1->start_node;
      caseno = 3;
    }
    else if ( e1->start_node == e2->end_node )
    {
      commonnode = e1->start_node;
      caseno = 4;
    }
    /* Check if any other edge is connected to the common node, if found */
    if ( commonnode != -1 )
    {
      num_node_edges = 1;
      node_edges = lwt_be_getEdgeByNode( topo, &commonnode,
                                         &num_node_edges, LWT_COL_EDGE_EDGE_ID );
      if ( num_node_edges == -1 ) {
        _lwt_release_edges(edges, nedges);
        lwerror("Backend error: %s", lwt_be_lastErrorMessage(topo->be_iface));
        return -1;
      }
      for (i=0; i<num_node_edges; ++i)
      {
        int r;
        if ( node_edges[i].edge_id == eid1 ) continue;
        if ( node_edges[i].edge_id == eid2 ) continue;
        commonnode = -1;
        /* append to string, for error message */
        if ( bufleft > 0 ) {
          r = snprintf(ptr, bufleft, "%s%" LWTFMT_ELEMID,
                       ( ptr==buf ? "" : "," ), node_edges[i].edge_id);
          if ( r >= (int) bufleft )
          {
            bufleft = 0;
            buf[252] = '.';
            buf[253] = '.';
            buf[254] = '.';
            buf[255] = '\0';
          }
          else
          {
            bufleft -= r;
            ptr += r;
          }
        }
      }
      if ( num_node_edges ) lwfree(node_edges);
    }
  }
 
  if ( commonnode == -1 )
  {
    _lwt_release_edges(edges, nedges);
    if ( ptr != buf )
    {
      lwerror("SQL/MM Spatial exception - other edges connected (%s)",
              buf);
    }
    else
    {
      lwerror("SQL/MM Spatial exception - non-connected edges");
    }
    return -1;
  }
 
  if ( ! lwt_be_checkTopoGeomRemNode(topo, commonnode,
                                     eid1, eid2 ) )
  {
    _lwt_release_edges(edges, nedges);
    lwerror("%s", lwt_be_lastErrorMessage(topo->be_iface));
    return -1;
  }
 
  /* Construct the geometry of the new edge */
  switch (caseno)
  {
    case 1: /* e1.end = e2.start */
      pa = ptarray_clone_deep(e1->geom->points);
      //pa = ptarray_merge(pa, e2->geom->points);
      ptarray_append_ptarray(pa, e2->geom->points, 0);
      newedge.start_node = e1->start_node;
      newedge.end_node = e2->end_node;
      newedge.next_left = e2->next_left;
      newedge.next_right = e1->next_right;
      e1freenode = 1;
      e2freenode = -1;
      e2sign = 1;
      break;
    case 2: /* e1.end = e2.end */
    {
      POINTARRAY *pa2;
      pa2 = ptarray_clone_deep(e2->geom->points);
      ptarray_reverse_in_place(pa2);
      pa = ptarray_clone_deep(e1->geom->points);
      //pa = ptarray_merge(e1->geom->points, pa);
      ptarray_append_ptarray(pa, pa2, 0);
      ptarray_free(pa2);
      newedge.start_node = e1->start_node;
      newedge.end_node = e2->start_node;
      newedge.next_left = e2->next_right;
      newedge.next_right = e1->next_right;
      e1freenode = 1;
      e2freenode = 1;
      e2sign = -1;
      break;
    }
    case 3: /* e1.start = e2.start */
      pa = ptarray_clone_deep(e2->geom->points);
      ptarray_reverse_in_place(pa);
      //pa = ptarray_merge(pa, e1->geom->points);
      ptarray_append_ptarray(pa, e1->geom->points, 0);
      newedge.end_node = e1->end_node;
      newedge.start_node = e2->end_node;
      newedge.next_left = e1->next_left;
      newedge.next_right = e2->next_left;
      e1freenode = -1;
      e2freenode = -1;
      e2sign = -1;
      break;
    case 4: /* e1.start = e2.end */
      pa = ptarray_clone_deep(e2->geom->points);
      //pa = ptarray_merge(pa, e1->geom->points);
      ptarray_append_ptarray(pa, e1->geom->points, 0);
      newedge.end_node = e1->end_node;
      newedge.start_node = e2->start_node;
      newedge.next_left = e1->next_left;
      newedge.next_right = e2->next_right;
      e1freenode = -1;
      e2freenode = 1;
      e2sign = 1;
      break;
    default:
      pa = NULL;
      e1freenode = 0;
      e2freenode = 0;
      e2sign = 0;
      _lwt_release_edges(edges, nedges);
      lwerror("Coding error: caseno=%d should never happen", caseno);
      break;
  }
  newedge.geom = lwline_construct(topo->srid, NULL, pa);
 
  if ( modEdge )
  {
    /* Update data of the first edge */
    newedge.edge_id = eid1;
    i = lwt_be_updateEdgesById(topo, &newedge, 1,
                               LWT_COL_EDGE_NEXT_LEFT|
                               LWT_COL_EDGE_NEXT_RIGHT |
                               LWT_COL_EDGE_START_NODE |
                               LWT_COL_EDGE_END_NODE |
                               LWT_COL_EDGE_GEOM);
    if ( i == -1 )
    {
      lwline_free(newedge.geom);
      _lwt_release_edges(edges, nedges);
      lwerror("Backend error: %s", lwt_be_lastErrorMessage(topo->be_iface));
      return -1;
    }
    else if ( i != 1 )
    {
      lwline_free(newedge.geom);
      if ( edges ) _lwt_release_edges(edges, nedges);
      lwerror("Unexpected error: %d edges updated when expecting 1", i);
      return -1;
    }
  }
  else
  {
    /* Add new edge */
    newedge.edge_id = -1;
    newedge.face_left = e1->face_left;
    newedge.face_right = e1->face_right;
    i = lwt_be_insertEdges(topo, &newedge, 1);
    if ( i == -1 ) {
      lwline_free(newedge.geom);
      _lwt_release_edges(edges, nedges);
      lwerror("Backend error: %s", lwt_be_lastErrorMessage(topo->be_iface));
      return -1;
    } else if ( i == 0 ) {
      lwline_free(newedge.geom);
      _lwt_release_edges(edges, nedges);
      lwerror("Insertion of split edge failed (no reason)");
      return -1;
    }
  }
  lwline_free(newedge.geom);
 
  /*
  -- Update next_left_edge/next_right_edge for
  -- any edge having them still pointing at the edge being removed
  -- (eid2 only when modEdge, or both otherwise)
  --
  -- NOTE:
  -- e#freenode is 1 when edge# end node was the common node
  -- and -1 otherwise. This gives the sign of possibly found references
  -- to its "free" (non connected to other edge) endnode.
  -- e2sign is -1 if edge1 direction is opposite to edge2 direction,
  -- or 1 otherwise.
  --
  */
 
  /* update edges connected to e2's boundary from their end node */
  seledge.next_left = e2freenode * eid2;
  updedge.next_left = e2freenode * newedge.edge_id * e2sign;
  i = lwt_be_updateEdges(topo, &seledge, LWT_COL_EDGE_NEXT_LEFT,
                               &updedge, LWT_COL_EDGE_NEXT_LEFT,
                               NULL, 0);
  if ( i == -1 )
  {
    _lwt_release_edges(edges, nedges);
    lwerror("Backend error: %s", lwt_be_lastErrorMessage(topo->be_iface));
    return -1;
  }
 
  /* update edges connected to e2's boundary from their start node */
  seledge.next_right = e2freenode * eid2;
  updedge.next_right = e2freenode * newedge.edge_id * e2sign;
  i = lwt_be_updateEdges(topo, &seledge, LWT_COL_EDGE_NEXT_RIGHT,
                               &updedge, LWT_COL_EDGE_NEXT_RIGHT,
                               NULL, 0);
  if ( i == -1 )
  {
    _lwt_release_edges(edges, nedges);
    lwerror("Backend error: %s", lwt_be_lastErrorMessage(topo->be_iface));
    return -1;
  }
 
  if ( ! modEdge )
  {
    /* update edges connected to e1's boundary from their end node */
    seledge.next_left = e1freenode * eid1;
    updedge.next_left = e1freenode * newedge.edge_id;
    i = lwt_be_updateEdges(topo, &seledge, LWT_COL_EDGE_NEXT_LEFT,
                                 &updedge, LWT_COL_EDGE_NEXT_LEFT,
                                 NULL, 0);
    if ( i == -1 )
    {
      _lwt_release_edges(edges, nedges);
      lwerror("Backend error: %s", lwt_be_lastErrorMessage(topo->be_iface));
      return -1;
    }
 
    /* update edges connected to e1's boundary from their start node */
    seledge.next_right = e1freenode * eid1;
    updedge.next_right = e1freenode * newedge.edge_id;
    i = lwt_be_updateEdges(topo, &seledge, LWT_COL_EDGE_NEXT_RIGHT,
                                 &updedge, LWT_COL_EDGE_NEXT_RIGHT,
                                 NULL, 0);
    if ( i == -1 )
    {
      _lwt_release_edges(edges, nedges);
      lwerror("Backend error: %s", lwt_be_lastErrorMessage(topo->be_iface));
      return -1;
    }
  }
 
  /* delete the edges (only second on modEdge or both) */
  i = lwt_be_deleteEdges(topo, e2, LWT_COL_EDGE_EDGE_ID);
  if ( i == -1 )
  {
    _lwt_release_edges(edges, nedges);
    lwerror("Backend error: %s", lwt_be_lastErrorMessage(topo->be_iface));
    return -1;
  }
  if ( ! modEdge ) {
    i = lwt_be_deleteEdges(topo, e1, LWT_COL_EDGE_EDGE_ID);
    if ( i == -1 )
    {
      _lwt_release_edges(edges, nedges);
      lwerror("Backend error: %s", lwt_be_lastErrorMessage(topo->be_iface));
      return -1;
    }
  }
 
  _lwt_release_edges(edges, nedges);
 
  /* delete the common node */
  i = lwt_be_deleteNodesById( topo, &commonnode, 1 );
  if ( i == -1 )
  {
    lwerror("Backend error: %s", lwt_be_lastErrorMessage(topo->be_iface));
    return -1;
  }
 
  /*
  --
  -- NOT IN THE SPECS:
  -- Drop composition rows involving second
  -- edge, as the first edge took its space,
  -- and all affected TopoGeom have been previously checked
  -- for being composed by both edges.
  */
  if ( ! lwt_be_updateTopoGeomEdgeHeal(topo,
                                eid1, eid2, newedge.edge_id) )
  {
    lwerror("%s", lwt_be_lastErrorMessage(topo->be_iface));
    return -1;
  }
 
  return modEdge ? commonnode : newedge.edge_id;
}

References _lwt_release_edges(), LWT_TOPOLOGY_T::be_iface, LWT_ISO_EDGE::edge_id, LWT_ISO_EDGE::end_node, LWT_ISO_EDGE::face_left, LWT_ISO_EDGE::face_right, LWT_ISO_EDGE::geom, lwerror(), lwfree(), lwline_construct(), lwline_free(), lwt_be_checkTopoGeomRemNode(), lwt_be_deleteEdges(), lwt_be_deleteNodesById(), lwt_be_getEdgeById(), lwt_be_getEdgeByNode(), lwt_be_insertEdges(), lwt_be_lastErrorMessage(), lwt_be_updateEdges(), lwt_be_updateEdgesById(), lwt_be_updateTopoGeomEdgeHeal(), LWT_COL_EDGE_ALL, LWT_COL_EDGE_EDGE_ID, LWT_COL_EDGE_END_NODE, LWT_COL_EDGE_GEOM, LWT_COL_EDGE_NEXT_LEFT, LWT_COL_EDGE_NEXT_RIGHT, LWT_COL_EDGE_START_NODE, LWTFMT_ELEMID, LWT_ISO_EDGE::next_left, LWT_ISO_EDGE::next_right, LWLINE::points, ptarray_append_ptarray(), ptarray_clone_deep(), ptarray_free(), ptarray_reverse_in_place(), r, LWT_TOPOLOGY_T::srid, and LWT_ISO_EDGE::start_node.

Referenced by lwt_ModEdgeHeal(), and lwt_NewEdgeHeal().

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