geo::ROOTGeoNodeForwardIterator Class Reference

Iterator to navigate through all the nodes. More...

Classes
struct	NodeInfo_t

Public Member Functions
	ROOTGeoNodeForwardIterator (TGeoNode const *start_node)
TGeoNode const *	operator* () const
	Returns the pointer to the current node, or nullptr if none. More...
ROOTGeoNodeForwardIterator &	operator++ ()
	Points to the next node, or to nullptr if there are no more. More...
std::vector< TGeoNode const * >	get_path () const
	Returns the full path of the current node. More...

Private Member Functions
void	reach_deepest_descendant ()

Private Attributes
std::vector< NodeInfo_t >	current_path
	which node, which sibling? More...

Detailed Description

Iterator to navigate through all the nodes.

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Note that this is not a fully standard forward iterator in that it lacks of the postfix operator. The reason is that it's too expensive and it should be avoided. Also I did not bother declaring the standard type definitions (that's just laziness).

An example of iteration:

TGeoNode const* pCurrentNode;

ROOTGeoNodeForwardIterator iNode(geom->ROOTGeoManager()->GetTopNode());
while ((pCurrentNode = *iNode)) {
  // do something with pCurrentNode
  ++iNode;
} // while

These iterators are one use only, and they can't be reset after a loop is completed.

Definition at line 562 of file GeometryCore.cxx.

Constructor & Destructor Documentation

geo::ROOTGeoNodeForwardIterator::ROOTGeoNodeForwardIterator ( TGeoNode const *  start_node )

explicit

Definition at line 1675 of file GeometryCore.cxx.

  {
    if (start_node) {
      current_path.push_back({start_node, 0U});
      reach_deepest_descendant();
    }
  }

Member Function Documentation

std::vector< TGeoNode const * > geo::ROOTGeoNodeForwardIterator::get_path

(

)

const

Returns the full path of the current node.

Definition at line 1706 of file GeometryCore.cxx.

Referenced by geo::CollectPathsByName::operator()().

  {
    std::vector<TGeoNode const*> node_path(current_path.size());
    std::transform(current_path.begin(),
                   current_path.end(),
                   node_path.begin(),
                   [](NodeInfo_t const& node_info) { return node_info.self; });
    return node_path;
  }

TGeoNode const* geo::ROOTGeoNodeForwardIterator::operator* ( ) const

inline

Returns the pointer to the current node, or nullptr if none.

Definition at line 567 of file GeometryCore.cxx.

    {
      return current_path.empty() ? nullptr : current_path.back().self;
    }

ROOTGeoNodeForwardIterator & geo::ROOTGeoNodeForwardIterator::operator++

(

)

Points to the next node, or to nullptr if there are no more.

Definition at line 1683 of file GeometryCore.cxx.

References geo::ROOTGeoNodeForwardIterator::NodeInfo_t::self, and geo::ROOTGeoNodeForwardIterator::NodeInfo_t::sibling.

  {
    if (current_path.empty()) return *this;
    if (current_path.size() == 1) {
      current_path.pop_back();
      return *this;
    }

    // I am done; all my descendants were also done already;
    // first look at my younger siblings
    NodeInfo_t& current = current_path.back();
    NodeInfo_t const& parent = current_path[current_path.size() - 2];
    if (++(current.sibling) < parent.self->GetNdaughters()) {
      // my next sibling exists, let's parse his descendents
      current.self = parent.self->GetDaughter(current.sibling);
      reach_deepest_descendant();
    }
    else
      current_path.pop_back(); // no sibling, it's time for mum
    return *this;
  }

void geo::ROOTGeoNodeForwardIterator::reach_deepest_descendant ( )

private

Definition at line 1717 of file GeometryCore.cxx.

  {
    TGeoNode const* descendent = current_path.back().self;
    while (descendent->GetNdaughters() > 0) {
      descendent = descendent->GetDaughter(0);
      current_path.push_back({descendent, 0U});
    }
  }

Member Data Documentation

std::vector<NodeInfo_t> geo::ROOTGeoNodeForwardIterator::current_path

private

which node, which sibling?

Definition at line 585 of file GeometryCore.cxx.

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The documentation for this class was generated from the following file:

• larcorealg/v09_13_01/source/larcorealg/Geometry/GeometryCore.cxx