gar::geo::ROOTGeoNodeForwardIterator Class Reference

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

#include <GeometryCore.h>

Classes
struct	NodeInfo_t

Public Member Functions
	ROOTGeoNodeForwardIterator (TGeoNode const *start_node)
	Constructor: start from this node. More...
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...

Protected Types
using	Node_t = TGeoNode const *

Protected Member Functions
void	reach_deepest_descendant ()
void	init (TGeoNode const *start_node)

Protected 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 1310 of file GeometryCore.h.

Member Typedef Documentation

using gar::geo::ROOTGeoNodeForwardIterator::Node_t = TGeoNode const*

protected

Definition at line 1325 of file GeometryCore.h.

Constructor & Destructor Documentation

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

inline

Constructor: start from this node.

Definition at line 1313 of file GeometryCore.h.

{ init(start_node); }

Member Function Documentation

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

(

)

const

Returns the full path of the current node.

Definition at line 2013 of file GeometryCore.cxx.

                                                                          {

      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;

    } // ROOTGeoNodeForwardIterator::path()

void gar::geo::ROOTGeoNodeForwardIterator::init ( TGeoNode const *  start_node )

protected

Definition at line 2034 of file GeometryCore.cxx.

                                                                    {
      current_path.clear();
      if (!start_node) return;
      current_path.emplace_back(start_node, 0U);
      reach_deepest_descendant();
    } // ROOTGeoNodeForwardIterator::init()

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

inline

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

Definition at line 1316 of file GeometryCore.h.

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

ROOTGeoNodeForwardIterator & gar::geo::ROOTGeoNodeForwardIterator::operator++

(

)

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

Definition at line 1994 of file GeometryCore.cxx.

                                                                        {
      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;
    } // ROOTGeoNodeForwardIterator::operator++

void gar::geo::ROOTGeoNodeForwardIterator::reach_deepest_descendant ( )

protected

Definition at line 2025 of file GeometryCore.cxx.

                                                              {
      Node_t descendent = current_path.back().self;
      while (descendent->GetNdaughters() > 0) {
        descendent = descendent->GetDaughter(0);
        current_path.emplace_back(descendent, 0U);
      } // while
    } // ROOTGeoNodeForwardIterator::reach_deepest_descendant()

Member Data Documentation

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

protected

which node, which sibling?

Definition at line 1333 of file GeometryCore.h.

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

• garsoft/Geometry/GeometryCore.h
• garsoft/Geometry/GeometryCore.cxx