geo_vectors_utils.h File Reference

Utilities to extend the interface of geometry vectors. More...

#include "larcoreobj/SimpleTypesAndConstants/geo_vectors.h"
#include <array>
#include <vector>
#include <iterator>
#include <type_traits>
#include <functional>
#include <cassert>

Go to the source code of this file.

Classes
struct	geo::vect::details::AccumulateImpl< Op, T >
struct	geo::vect::details::AccumulateImpl< Op, First, Second, Others... >
struct	geo::vect::details::AccumulateImpl< Op, T >
struct	geo::vect::details::VectorScalar< Vector >
struct	geo::vect::details::HasGetter< Vector >
struct	geo::vect::details::MemberFuncReturnType< T >
struct	geo::vect::details::MemberFuncClassType< T >
struct	geo::vect::details::MemberFuncClassType< Func Class::* >
struct	geo::vect::details::BaseCoordTypes< Vector, SetterType >
struct	geo::vect::details::BaseCoordTypes< Vector, void >
struct	geo::vect::details::BaseCoordTypes< Vector, SetterType >
struct	geo::vect::details::CoordGetterTraits< Vector >
class	geo::vect::details::CoordGetter< Vector >
	Helper class for read of a single vector coordinate. More...
struct	geo::vect::details::CoordManagerTraits< Vector, SetterType >
class	geo::vect::details::CoordManager< Vector, SetterType >
	Helper class for read/write of a single vector coordinate. More...
class	geo::vect::details::BoundCoordGetter< CoordHelper, StoredVector >
class	geo::vect::details::BoundCoordManager< CoordHelper, StoredVector >
class	geo::vect::MiddlePointAccumulatorDim< N >
	Helper class to compute the middle point in a point set. More...
struct	geo::vect::details::AlwaysFalse< typename >
struct	geo::vect::details::CoordManagerImpl< Vector, Dim >
struct	geo::vect::details::CoordManagerImpl< Vector, 1U >
struct	geo::vect::details::CoordManagerImpl< Vector, 2U >
struct	geo::vect::details::CoordManagerImpl< Vector, 3U >
struct	geo::vect::details::CoordManagerImpl< Vector, 4U >
struct	geo::vect::details::CoordManagersImplBase< Vector, N >
struct	geo::vect::details::CoordManagersImpl< Vector, N >
struct	geo::vect::details::CoordManagersImpl< Vector, 2U >
struct	geo::vect::details::CoordManagersImpl< Vector, 3U >
struct	geo::vect::details::CoordManagersImpl< Vector, 4U >
struct	geo::vect::details::BindCoordManagersImplBase< Vector, N >
struct	geo::vect::details::BindCoordManagersImpl< Vector, N >
struct	geo::vect::details::BindCoordManagersImpl< Vector, 2U >
struct	geo::vect::details::BindCoordManagersImpl< Vector, 3U >
struct	geo::vect::details::BindCoordManagersImpl< Vector, 4U >
struct	geo::vect::details::ConvertToImplBase< Dest, Source >
struct	geo::vect::details::ConvertToImpl< Dest, Source, Dim >
struct	geo::vect::details::ConvertToImpl< Dest, Source, 2U >
struct	geo::vect::details::ConvertToImpl< Dest, Source, 3U >
struct	geo::vect::details::ConvertToImpl< Dest, Source, 4U >
struct	geo::vect::details::ConvertToDispatcher< Dest, Source, Dim >
struct	geo::vect::details::ConvertToDispatcher< Vector, Vector, Dim >

Namespaces
	geo
	Namespace collecting geometry-related classes utilities.
	geo::vect
	Utilities to manipulate geometry vectors.The utilities include generic vector interface facilities allowing to use different vector types via templates.
	geo::vect::details
	geo::vect::extra
	Convenience utilities not directly related to vectors.

Typedefs
template<typename Vector >
using	geo::vect::details::VectorScalar_t = typename VectorScalar< Vector >::type
template<typename Vector >
using	geo::vect::details::CoordinateArray_t = std::array< VectorScalar_t< Vector >, dimension< Vector >()>
	A STL array suitable to contain all coordinate values of a Vector. More...
template<typename T >
using	geo::vect::details::MemberFuncReturn_t = typename MemberFuncReturnType< T >::type
template<typename T >
using	geo::vect::details::MemberFuncClass_t = typename MemberFuncClassType< T >::type
template<typename Vector >
using	geo::vect::coordinate_t = details::VectorScalar_t< Vector >
	Type of coordinate of the specified vector type. More...
template<typename Vector >
using	geo::vect::CoordReader_t = decltype(details::makeCoordReader(&Vector::X))
	Type of a coordinate reader for a vector type. More...
template<typename Vector >
using	geo::vect::CoordManager_t = decltype(details::makeCoordManager(&Vector::X,&Vector::SetX))
	Type of a coordinate manager for a vector type. More...
using	geo::vect::MiddlePointAccumulator = MiddlePointAccumulatorDim< 3U >
	Middle-point accumulator for vectors of dimension 3. More...
template<typename Vector >
using	geo::vect::details::VectorIndices_t = std::make_index_sequence< dimension< Vector >()>
	Type of sequence of indices up to Vector size. More...

Functions
template<typename Op , typename... T>
auto	geo::vect::details::extended_accumulate (Op op, T &&...args)
template<typename... T>
auto	geo::vect::details::extended_and (T...args) -> decltype(auto)
template<typename Vector >
constexpr bool	geo::vect::details::HasX ()
template<typename Vector >
constexpr bool	geo::vect::details::HasY ()
template<typename Vector >
constexpr bool	geo::vect::details::HasZ ()
template<typename Vector >
constexpr bool	geo::vect::details::HasT ()
template<typename Vector >
constexpr unsigned int	geo::vect::details::dimension ()
template<typename Getter >
constexpr auto	geo::vect::details::makeCoordReader (Getter getter)
template<typename Getter , typename Setter >
constexpr auto	geo::vect::details::makeCoordManager (Getter getter, Setter setter)
template<typename T >
T	geo::vect::extra::roundValue01 (T value, T tol)
	Returns value, rounded to 0, -1 or +1 if closer than tol. More...
template<typename Vector , typename Coords >
constexpr Vector	geo::vect::makeFromCoords (Coords &&coords)
	Creates a Vector object with coordinates from coords. More...
template<typename Vector >
constexpr auto	geo::vect::coordManager (unsigned int n)
	Returns an object that can be bound to a vector to manage one of its coordinates. More...
template<typename Vector >
constexpr auto	geo::vect::coordManager (unsigned int n, Vector &v)
	Returns an object that can be bound to a vector to manage one of its coordinates. More...
template<typename Vector >
constexpr auto	geo::vect::bindCoord (Vector const &v, CoordReader_t< Vector > helper)
	Binds the specified constant vector to the coordinate reader. More...
template<typename Vector >
auto	geo::vect::bindCoord (Vector &v, CoordManager_t< Vector > helper) -> details::BoundCoordManager< CoordManager_t< Vector >, Vector >
	Binds the specified vector to the coordinate manager. More...
template<typename Vector >
auto	geo::vect::Xcoord (Vector &v)
	Returns an object to manage the coordinate X of the vector v. More...
template<typename Vector >
auto	geo::vect::Ycoord (Vector &v)
	Returns an object to manage the coordinate Y of the vector v. More...
template<typename Vector >
auto	geo::vect::Zcoord (Vector &v)
	Returns an object to manage the coordinate Z of the vector v. More...
template<typename Vector >
auto	geo::vect::Tcoord (Vector &v)
	Returns an object to manage the coordinate T of the vector v. More...
template<typename Vector >
auto	geo::vect::coord (Vector &v, unsigned int n) noexcept
	Returns an object to manage the coordinate n of a vector. More...
template<typename Vector >
constexpr auto	geo::vect::bindCoordManagers (Vector &v)
template<typename Vector >
constexpr auto	geo::vect::bindCoordReaders (Vector const &v)
template<typename Dest , typename Source >
Dest	geo::vect::convertTo (Source const &v)
	Returns a vector of type Dest with the same content as a Src. More...
template<typename Dest , typename Source >
std::vector< Dest >	geo::vect::convertCollTo (std::vector< Source > const &coll)
	Returns a vector of type Dest with the same content as a Src. More...
template<typename Vector , typename Pred >
Vector	geo::vect::transformCoords (Vector const &v, Pred &&pred)
	Returns a new vector applying a predicate to each component. More...
template<>
auto	geo::vect::norm (geo::Vector_t const &v)
template<typename T >
constexpr T &&	geo::vect::details::constexpr_forward (std::remove_reference_t< T > &t)
template<typename T >
constexpr T &&	geo::vect::details::constexpr_forward (std::remove_reference_t< T > &&t)
template<typename Vector >
constexpr auto	geo::vect::details::makeVectorIndices ()
template<typename Vector >
constexpr auto	geo::vect::details::makeVectorIndices (Vector &&)
template<typename T , T... Indices>
constexpr auto	geo::vect::details::makeIndexSeqImpl (std::integer_sequence< T, Indices... >)
template<typename T , T N>
constexpr auto	geo::vect::details::makeIndexSeq ()
template<std::size_t I, typename Data >
constexpr auto	geo::vect::details::accessElement (Data &&data)
template<typename Vector , typename Coords , std::size_t... Indices>
constexpr Vector	geo::vect::details::makeFromCoordsImpl (Coords &&coords, std::index_sequence< Indices... >)
template<typename Point , std::size_t... I>
bool	geo::vect::details::isfiniteImpl (Point const &point, std::index_sequence< I... >)
Vector coordinate access abstraction
This group of utilities provides a common interface for tasks involving geometry vectors, which may have different interface. An example of that is the access of coordinates by an index: it is supported (and "slow") in TVector3 for read/write access, while in GenVector it is not supported (and given that the internal representation might be not cartesian, it's not surprising). We provide utilities which fill the gaps, relying on some looser requirements. Coordinate managers A "coordinate manager" is an object handling a specific coordinate out of a specific vector type; i.e., a coordinate manager object will manage for its entire lifetime the same coordinate, e.g. x or z. A coordinate manager can be: bound to a vector object: that manager handles exclusively its managed coordinate for that vector object; unbound: such a manager can handle the managed coordinate of any vector, which can be passed as an argument; or the unbound manager can be used to create a bound one. Two types of managers are available: reader, accesses the coordinate but can't modify it manager, requires to be bound to a mutable vector and can assign and modify the coordinate via selected operations Note that a coordinate is never returned as a reference, either mutable or constant. Handling a coordinate of a vector object: bound managers A bound coordinate manager can be created directly: geo::Point_t p { 1.0, 2.0, 3.0 }; auto px = geo::vect::Xcoord(p); std::cout << p << " has x=" << px() << std::endl; px += 5.0; std::cout << p << " has now x=" << px() << std::endl; will return something along the line of (1,2,3) has x=1 (6,2,3) has now x=6 Functions Xcoord(), Ycoord(), Zcoord() and Tcoord() (in namespace geo::vect) are available for the supporting vector types. If access by numeric index is necessary, coord() can be used instead: geo::Vector_t const v { 1.0, 2.0, 3.0 }; for (unsigned c = 0; c < 3; ++c) { auto vc = geo::vect::coord(v, c); std::cout << v << "[" << c << "]=" << vc() << std::endl; } (note that for this example we have implicitly obtained a coordinate reader instead of a full coordinate manager because v is constant). This will print: v[0]=1 v[1]=2 v[2]=3 If there are more vectors to access the same coordinate of, it's better to use unbound managers (see below). Handling a coordinate for any vector object Unbound coordinate managers (and readers) can't operate directly on vectors but they need to be bound to one. Binding produces a new bound manager, leaving the unbound manager untouched. Binding is done with geo::vect::bindCoord(). For example: geo::Point_t A { 1.0, 2.0, 3.0 }; auto Ax = geo::vect::bindCoord(A, YcoordManager<geo::Point_t>); std::cout << A << " has y=" << Ax << std::endl; should produce an output like (1,2,3) has y=2 In the example, YcoordManager is a template coordinate manager. There are managers available for X, Y, Z and T coordinates, and each one can deal only with a specific vector type; also, specifying a non-constant vector type will deliver a full manager, which can't operate on constant vectors. The unbound coordinate managers are not as useful, but a possible use is for loops on coordinates from multiple vectors: geo::Point_t A { 1.0, 2.0, 3.0 }, geo::Point_t B {5.0, 7.0, 9.0 }; for (unsigned c = 0; c < 3; ++c) { auto coordMan = geo::vect::coordManager(c); auto Ac = geo::vect::bindCoord(A, coordMan); auto Bc = geo::vect::bindCoord(B, coordMan); std::cout << (Bc() - Ac() * 2.0) << std::endl; } // for which will emit 3 3 3 This is marginally faster than the same code with geo::vect::bindCoord() call replaced by geo::vect::coord(). More convenient still, if the coordinates are treated all just the same and c is not needed (as above): geo::Point_t A { 1.0, 2.0, 3.0 }, geo::Point_t B {5.0, 7.0, 9.0 }; for (auto coordMan: geo::vect::coordManagers<geo::Point_t const>()) { auto Ac = geo::vect::bindCoord(A, coordMan); auto Bc = geo::vect::bindCoord(B, coordMan); std::cout << (Bc() - Ac() * 2.0) << std::endl; } // for Conversion between vector types A convenience function convertTo() is provided to convert a vector into another of a different type (for example, from TVector3 to geo::Vector_t). Vector requirements So far, the requirements for this set of utilities are the following. The vector type must support: a cartesian coordinate constructor: Vector v { 1.0, 2.0, 3.0 }; accessor methods named after the name of the coordinate, acting on constant vectors, taking no arguments, and returning a copy of the coordinate value, e.g. double X() const coordinate assignment methods named SetC, where C is the name of each coordinate, after the name of the coordinate, with a single argument; the return type is not prescribed; e.g. void SetY(double) the coordinate names must be X and Y for 2D vectors, plus Z for 3D vectors and T for 4D vectors (metric is irrelevant here)
template<typename Vector >
constexpr unsigned int	geo::vect::dimension ()
	Returns the dimension of the specified vector type. More...
template<typename Vector >
constexpr unsigned int	geo::vect::dimension (Vector &&)
	Returns the dimension of the specified vector type. More...
template<typename Vector >
constexpr std::array< std::size_t, geo::vect::dimension< Vector >)>	geo::vect::indices ()
	Returns a sequence of indices valid for a vector of the specified type. More...
template<typename Vector >
constexpr auto	geo::vect::indices (Vector const &) -> decltype(indices< Vector >())
	Returns a sequence of indices valid for a vector of the specified type. More...
template<typename Vector >
constexpr auto	geo::vect::coordManagers ()
	Returns an array with all coordinate managers for a type of vector. More...
template<typename Vector >
constexpr auto	geo::vect::coordManagers (Vector &&)
	Returns an array with all coordinate managers for a type of vector. More...
template<typename Vector >
constexpr auto	geo::vect::coordReaders ()
	Returns an array with all coordinate readers for a type of vector. More...
template<typename Vector >
constexpr auto	geo::vect::coordReaders (Vector &&)
	Returns an array with all coordinate readers for a type of vector. More...
Functions for common vector operations.
This group of template functions are meant to be used with vectors in a generic way. The default implementation is for TVector3. Specializations can be easily written for other vector types. In addition, two "standard" representations for vectors and points are provided. Note The representations for vector and point objects are currently the same; this prevents relying on overload resolution to decide which function to use. For example, defining two functions with signature: Vector_t Project(Vector_t const& v); Point_t Project(Point_t const& v); will not compile since these two are exactly the same. A solution might be to derive two different classes from the common one: struct Vector_t: public VectorBase_t { using VectorBase_t::VectorBase_t; }; struct Point_t: public VectorBase_t { using VectorBase_t::VectorBase_t; }; This will likely have consequences though (for example, the sum of two Vector_t or Point_t will become a VectorBase_t).
template<typename Vector , typename Scalar >
Vector	geo::vect::rounded01 (Vector const &v, Scalar tol)
	Returns a vector with all components rounded if close to 0, -1 or +1. More...
template<typename Vector , typename Scalar >
void	geo::vect::round01 (Vector &v, Scalar tol)
	Returns a vector with all components rounded if close to 0, -1 or +1. More...
template<typename Vector >
bool	geo::vect::isfinite (Vector const &v)
	Returns whether all components of the vector are finite. More...
template<typename Vector >
Vector	geo::vect::normalize (Vector const &v)
	Returns a vector parallel to v and with norm 1. More...
template<typename Vector >
Vector	geo::vect::cross (Vector const &a, Vector const &b)
	Return cross product of two vectors. More...
template<typename Vector >
constexpr auto	geo::vect::dot (Vector const &a, Vector const &b)
	Return cross product of two vectors. More...
template<typename Vector >
auto	geo::vect::mag2 (Vector const &v)
	Return norm of the specified vector. More...
template<typename Vector >
auto	geo::vect::norm (Vector const &v)
	Return norm of the specified vector. More...
template<typename Vector >
auto	geo::vect::mixedProduct (Vector const &a, Vector const &b, Vector const &c)
Middle point functions
template<typename Point , typename BeginIter , typename EndIter >
Point	geo::vect::middlePointAs (BeginIter begin, EndIter end)
	Returns the middle of the specified points. More...
template<typename BeginIter , typename EndIter >
geo::Point_t	geo::vect::middlePoint (BeginIter begin, EndIter end)
	Returns the middle of the specified points. More...
template<typename Point >
Point	geo::vect::middlePoint (std::initializer_list< Point > points)
	Returns the middle of the specified points. More...
Support for LArSoft geometry vectors
template<typename Point >
::geo::Point_t	geo::vect::toPoint (Point const &p)
	Convert the specified point into a geo::Point_t. More...
template<typename Vector >
::geo::Vector_t	geo::vect::toVector (Vector const &v)
	Convert the specified vector into a geo::Vector_t. More...
template<typename Point >
std::vector< geo::Point_t >	geo::vect::convertCollToPoint (std::vector< Point > const &coll)
template<typename Vector >
std::vector< geo::Vector_t >	geo::vect::convertCollToVector (std::vector< Vector > const &coll)
template<typename Coords >
GENVECTOR_CONSTEXPR::geo::Point_t	geo::vect::makePointFromCoords (Coords &&coords)
	Creates a geo::Point_t from its coordinates (see makeFromCoords()). More...
template<typename Coords >
GENVECTOR_CONSTEXPR::geo::Vector_t	geo::vect::makeVectorFromCoords (Coords &&coords)
	Creates a geo::Vector_t from its coordinates (see makeFromCoords()). More...

Variables
template<typename Vector >
static constexpr auto	geo::vect::XcoordManager = details::makeCoordManager(&Vector::X, &Vector::SetX)
	Object that can be bound to a vector to manage its X coordinate. More...
template<typename Vector >
static constexpr auto	geo::vect::XcoordManager< Vector const > = details::makeCoordReader(&Vector::X)
	Object that can be bound to a vector to access its X coordinate. More...
template<typename Vector >
static constexpr auto const	geo::vect::YcoordManager = details::makeCoordManager(&Vector::Y, &Vector::SetY)
template<typename Vector >
static constexpr auto	geo::vect::YcoordManager< Vector const > = details::makeCoordReader(&Vector::Y)
template<typename Vector >
static constexpr auto	geo::vect::ZcoordManager = details::makeCoordManager(&Vector::Z, &Vector::SetZ)
template<typename Vector >
static constexpr auto	geo::vect::ZcoordManager< Vector const > = details::makeCoordReader(&Vector::Z)
template<typename Vector >
static constexpr auto	geo::vect::TcoordManager = details::makeCoordManager(&Vector::T, &Vector::SetT)
template<typename Vector >
static constexpr auto	geo::vect::TcoordManager< Vector const > = details::makeCoordReader(&Vector::T)
template<typename Vector >
constexpr CoordManager_t< Vector >	geo::vect::details::NoCoordManager { nullptr, nullptr }

Detailed Description

Utilities to extend the interface of geometry vectors.

Author

Gianluca Petrillo (petri.nosp@m.llo@.nosp@m.fnal..nosp@m.gov)

Date

November 27, 2017

This library provides facilities that can be used for both LArSoft geometry vectors (geo_vectors.h) and ROOT TVector3 and related, with the same interface.

This library depends on ROOT GenVector. In the CET link list in CMakeLists.txt, link to ${ROOT_GENVECTOR}.

Definition in file geo_vectors_utils.h.