Acts::Experimental::SphericalSpacePointGrid Class Reference

A spherical space point grid for seeding, binned in (phi, eta, r). More...

#include <Acts/Seeding/SphericalSpacePointGrid.hpp>

Inheritance diagram for Acts::Experimental::SphericalSpacePointGrid:

Collaboration diagram for Acts::Experimental::SphericalSpacePointGrid:

Classes
struct	Config
	Configuration parameters for the spherical space point grid. More...

Public Types
using	CotThetaAxisType = GridBase::AxisTypeAt<1>
	Type alias for the middle (cot(theta)) axis with variable binning and open boundaries.
using	GridBase
	Type alias for the CRTP base class.
using	PhiAxisType = GridBase::AxisTypeAt<0>
	Type alias for the phi axis (equidistant binning, closed boundaries).
using	RAxisType = GridBase::AxisTypeAt<2>
	Type alias for the r axis (variable binning, open boundaries).

Public Member Functions
	SphericalSpacePointGrid (const Config &config, std::unique_ptr< const Logger > logger=getDefaultLogger("SphericalSpacePointGrid", Logging::Level::INFO))
	Construct a spherical space point grid with the given configuration and an optional logger.
std::optional< std::size_t >	binIndex (float phi, float cotTheta, float r) const
	Get the bin index for a space point.
Range1D< float >	computeRadiusRange (const SpacePointContainer &spacePoints) const
	Compute the range of radii in the grid.
std::optional< std::size_t >	insert (const ConstSpacePointProxy &sp)
	Insert a space point into the grid, binning it by cot(theta) = z / r (a single division; assumes r > 0); see the class documentation.
std::optional< std::size_t >	insert (SpacePointIndex index, float phi, float cotTheta, float r)
	Insert a space point into the grid.
void	sortBinsByR (const SpacePointContainer &spacePoints)
	Sort the bins in the grid by the space point radius, which is required by some algorithms that operate on the grid.

Detailed Description

A spherical space point grid for seeding, binned in (phi, eta, r).

A space point's eta bin is found from cot(theta) = z / r (a single division), matched against bin edges that are stored as sinh(eta). Since cot(theta) = sinh(eta), comparing z / r against those edges places the point into exactly its eta bin, with no atan2 / tan / log / asinh.

Member Typedef Documentation

CotThetaAxisType

using Acts::Experimental::SphericalSpacePointGrid::CotThetaAxisType = GridBase::AxisTypeAt<1>

Type alias for the middle (cot(theta)) axis with variable binning and open boundaries.

Edges are stored as sinh(eta) = cot(theta), so the binning is configured in eta while space points are placed by z / r (see class doc).

GridBase

using Acts::Experimental::SphericalSpacePointGrid::GridBase

Initial value:

 
      Acts::detail::SpacePointGridBase<SphericalSpacePointGrid, GridType>

Type alias for the CRTP base class.

Constructor & Destructor Documentation

SphericalSpacePointGrid()

Acts::Experimental::SphericalSpacePointGrid::SphericalSpacePointGrid ( const Config & config, std::unique_ptr< const Logger > logger = getDefaultLogger("SphericalSpacePointGrid", Logging::Level::INFO) )

explicit

Construct a spherical space point grid with the given configuration and an optional logger.

Parameters

config	Configuration for the spherical grid
logger	Optional logger instance for debugging output

Member Function Documentation

binIndex()

std::optional< std::size_t > Acts::Experimental::SphericalSpacePointGrid::binIndex	(	float	phi,
		float	cotTheta,
		float	r ) const

Get the bin index for a space point.

Parameters

phi	The azimuthal angle of the space point in radians
cotTheta	cot(theta) = z / r, used to place the point in its eta bin via cot(theta) = z / r = sinh(eta)
r	The radial distance of the space point from the origin

Returns

The index of the bin in which the space point is located, or std::nullopt if the space point is outside the grid bounds.

computeRadiusRange()

Range1D< float > Acts::Experimental::SphericalSpacePointGrid::computeRadiusRange

(

const SpacePointContainer &

spacePoints

)

const

Compute the range of radii in the grid.

This requires the grid to be filled with space points and sorted by radius. The sorting can be done with the sortBinsByR method.

Parameters

spacePoints

The space point container to compute the radius range

Returns

The range of radii in the grid

insert() [1/2]

std::optional< std::size_t > Acts::Experimental::SphericalSpacePointGrid::insert

(

const ConstSpacePointProxy &

sp

)

Insert a space point into the grid, binning it by cot(theta) = z / r (a single division; assumes r > 0); see the class documentation.

Parameters

sp	The space point to insert

Returns

The index of the bin in which the space point was inserted, or std::nullopt if the space point is outside the grid bounds.

insert() [2/2]

std::optional< std::size_t > Acts::Experimental::SphericalSpacePointGrid::insert	(	SpacePointIndex	index,
		float	phi,
		float	cotTheta,
		float	r )

Insert a space point into the grid.

Parameters

index	The index of the space point to insert
phi	The azimuthal angle of the space point in radians
cotTheta	cot(theta) = z / r, used to place the point in its eta bin via cot(theta) = z / r = sinh(eta)
r	The radial distance of the space point from the origin

Returns

The index of the bin in which the space point was inserted, or std::nullopt if the space point is outside the grid bounds.

sortBinsByR()

void Acts::Experimental::SphericalSpacePointGrid::sortBinsByR

(

const SpacePointContainer &

spacePoints

)

Sort the bins in the grid by the space point radius, which is required by some algorithms that operate on the grid.

Parameters

spacePoints

The space point container to sort the bins by radius