lwt_AddIsoNode()

LWT_ELEMID lwt_AddIsoNode	(	LWT_TOPOLOGY *	topo,
		LWT_ELEMID	face,
		LWPOINT *	pt,
		int	skipChecks
	)

Add an isolated node.

For ST_AddIsoNode

Parameters

topo	the topology to operate on
face	the identifier of containing face or -1 for "unknown"
pt	the node position
skipChecks	if non-zero skips consistency checks (coincident nodes, crossing edges, actual face containement)

Returns

ID of the newly added node, or -1 on error (liblwgeom error handler will be invoked with error message)

Definition at line 525 of file lwgeom_topo.c.

References LWT_TOPOLOGY_T::be_iface, LWT_ISO_NODE::containing_face, LWT_ISO_NODE::geom, lwerror(), lwt_be_ExistsCoincidentNode(), lwt_be_ExistsEdgeIntersectingPoint(), lwt_be_getFaceContainingPoint(), lwt_be_insertNodes(), lwt_be_lastErrorMessage(), and LWT_ISO_NODE::node_id.

Referenced by lwt_AddPoint().

{
  LWT_ELEMID foundInFace = -1;

  if ( ! skipISOChecks )
  {
    if ( lwt_be_ExistsCoincidentNode(topo, pt) ) /*x*/
    {
      lwerror("SQL/MM Spatial exception - coincident node");
      return -1;
    }
    if ( lwt_be_ExistsEdgeIntersectingPoint(topo, pt) ) /*x*/
    {
      lwerror("SQL/MM Spatial exception - edge crosses node.");
      return -1;
    }
  }

  if ( face == -1 || ! skipISOChecks )
  {
    foundInFace = lwt_be_getFaceContainingPoint(topo, pt); /*x*/
    if ( foundInFace == -2 ) {
      lwerror("Backend error: %s", lwt_be_lastErrorMessage(topo->be_iface));
      return -1;
    }
    if ( foundInFace == -1 ) foundInFace = 0;
  }

  if ( face == -1 ) {
    face = foundInFace;
  }
  else if ( ! skipISOChecks && foundInFace != face ) {
#if 0
    lwerror("SQL/MM Spatial exception - within face %d (not %d)",
            foundInFace, face);
#else
    lwerror("SQL/MM Spatial exception - not within face");
#endif
    return -1;
  }

  LWT_ISO_NODE node;
  node.node_id = -1;
  node.containing_face = face;
  node.geom = pt;
  if ( ! lwt_be_insertNodes(topo, &node, 1) )
  {
    lwerror("Backend error: %s", lwt_be_lastErrorMessage(topo->be_iface));
    return -1;
  }

  return node.node_id;
}

Here is the call graph for this function:

Here is the caller graph for this function: