geo::ROOTGeometryNavigator Class Reference

Executes an operation on all the nodes of the ROOT geometry. More...

#include <ROOTGeometryNavigator.h>

Public Member Functions
	ROOTGeometryNavigator (TGeoManager const &manager)
	Constructor: picks the manager. More...
template<typename Op >
bool	apply (geo::GeoNodePath &path, Op &&op) const
	Applies the specified operation to all nodes under the path. More...
template<typename Op >
bool	apply (TGeoNode const &node, Op &&op) const
	Applies the specified operation to all nodes under node. More...
template<typename Op >
bool	apply (Op &&op) const
	Applies the specified operation to all nodes. More...

Private Attributes
TGeoNode const *	fTopNode = nullptr

Detailed Description

Executes an operation on all the nodes of the ROOT geometry.

For example, to collect the path (see geo::GeoNodePath) of all the volumes named "volTPC" in the geometry loaded in LArSoft:

std::string const volumeName = "volTPC";

auto const& geom = *(lar::providerFrom<geo::Geometry>());

geo::ROOTGeometryNavigator navigator { *(geom.ROOTGeoManager()) };

// the operation executed on all nodes accumulates the paths in `volumePaths`
std::vector<geo::GeoNodePath> volumePaths;
auto findVolume = [&volumePaths, volumeName](auto& path)
  {
    if (path.current().GetVolume()->GetName() == volumeName)
      volumePaths.push_back(path);
    return true;
  };

geo::ROOTGeometryNavigator navigator { *(geom.ROOTGeoManager()) };

navigator.apply(findVolume);

Definition at line 64 of file ROOTGeometryNavigator.h.

Constructor & Destructor Documentation

geo::ROOTGeometryNavigator::ROOTGeometryNavigator ( TGeoManager const &  manager )

inline

Constructor: picks the manager.

Definition at line 71 of file ROOTGeometryNavigator.h.

    : fTopNode(manager.GetTopNode())
    {}

Member Function Documentation

template<typename Op >

bool geo::ROOTGeometryNavigator::apply	(	geo::GeoNodePath &	path,
		Op &&	op
	)		const

Applies the specified operation to all nodes under the path.

Template Parameters

Op	type of operation (see description)

Parameters

path	the path to the first node to operate on
op	operation to be applied

Returns

whether all nodes in the path were processed

The operation Op must be a callable accepting a geo::GeoNodePath immutable argument and returning a value convertible to boolean. If a call to op results into a false value, the recursion is terminated and false is returned. path will be pointing to the last node already processed.

The node at the head of the path is processed first, then for each daughter node, first the daughter itself then its own daughters, recursively.

Definition at line 128 of file ROOTGeometryNavigator.h.

                                                                        {
  if (!op(path)) return false;
  
  TGeoNode const& node = path.current();
  TGeoVolume const* pVolume = node.GetVolume();
  if (pVolume) { // is it even possible not to?
    int const nDaughters = pVolume->GetNdaughters();
    for (int iDaughter: util::counter<int>(nDaughters)) {
      TGeoNode const* pDaughter = pVolume->GetNode(iDaughter);
      if (!pDaughter) continue; // fishy...
      
      path.append(*pDaughter);
      if (!apply(path, std::forward<Op>(op))) return false;
      path.pop();
    } // for
  } // if we have a volume
  
  return true;
} // geo::ROOTGeometryNavigator::apply()

template<typename Op >

bool geo::ROOTGeometryNavigator::apply	(	TGeoNode const &	node,
		Op &&	op
	)		const

Applies the specified operation to all nodes under node.

Template Parameters

Op	type of operation (see description)

Parameters

node	the node to start from
op	operation to be applied

Returns

whether all nodes in the path were processed

See Also

apply(geo::GeoNodePath&, Op&&) const

The operation Op must be a callable accepting a geo::GeoNodePath immutable argument.

Definition at line 151 of file ROOTGeometryNavigator.h.

                                                                        {
  geo::GeoNodePath path { &node };
  return apply(path, std::forward<Op>(op));
} // geo::ROOTGeometryNavigator::apply()

template<typename Op >

bool geo::ROOTGeometryNavigator::apply

(

Op &&

op

)

const

Applies the specified operation to all nodes.

Template Parameters

Op	type of operation (see description)

Parameters

op	operation to be applied

Returns

whether all nodes in the path were processed

The operation Op must be a callable accepting a geo::GeoNodePath immutable argument.

Definition at line 159 of file ROOTGeometryNavigator.h.

                                                  {
  assert(fTopNode);
  return apply(*fTopNode, std::forward<Op>(op));
} // geo::ROOTGeometryNavigator::apply()

Member Data Documentation

TGeoNode const* geo::ROOTGeometryNavigator::fTopNode = nullptr

private

Definition at line 66 of file ROOTGeometryNavigator.h.

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

• ROOTGeometryNavigator.h