Detailed Description

Base class used for handling geometry in a multidetector array.

Each KVPosition object represents an element of solid angle, with a domain in polar angle (theta) and azimuthal angle (phi). All methods necessary to inquire about relative positions of such elements (overlaps, inclusion, etc.) are provided.

The coordinate system has the target position for its centre. The beam direction defines the positive z axis, with respect to which polar angles are measured. The +ve x-axis is taken to be vertical, and azimuthal angles increase when going clockwise from the +ve x-axis, looking towards the +ve z direction:

           phi=0
(x) beam    |
            |
            |
            +------- phi=90

All angles are in degrees.

Polar angles (theta) vary between 0 and 180 degrees Azimuthal angles (phi) vary between 0 and 359.999... degrees.

An element is defined by theta-min/max and phi-min/max:

Theta-min is the polar angle of the edge closest the beam (+ve z) axis
Theta-max is the polar angle of the edge furthest from the beam (+ve z) axis
Phi-min is the phi angle of the edge which is the most anticlockwise when looking as in the figure shown above
Phi-max is the phi angle of the edge which is the most clockwise when looking as in the figure shown above

The above definitions mean that phi-min is not necessarily smaller than phi-max: we redefine "smaller" for phi angles to mean "more anticlockwise than" or "less clockwise than". Some examples:

an element with phi-min = 20 and phi-max = 40 has an azimuthal width of 20 degrees;
an element with phi-min = 40 and phi-max = 20 has an azimuthal width of 340 degrees;
an element with phi-min = 350 and phi-max = 10 has an azimuthal width of 20 degrees.

Examples of use of KVPosition objects

Generating a random unit vector within a given angular range

KVPosition pos;                 |
pos.SetPolarMinMax(20, 30);     |  --  or:  KVPosition pos(20, 30, 0, 90);
pos.SetAzimuthalMinMax(0, 90);  |
TVector3 dir1 = pos.GetDirection();              //unit vector in direction theta=25, phi=45
TVector3 dir2 = pos.GetRandomDirection();        //isotropic direction within angular limits of pos
TVector3 dir3 = pos.GetRandomDirection("random");//random direction

Examples: ExampleAnalysis_KVEventMixerN_2Body.cpp, and ExampleCorrelationAnalysis.cpp.

Definition at line 91 of file KVPosition.h.

#include <KVPosition.h>

Inheritance diagram for KVPosition:

[legend]

Public Member Functions
	KVPosition ()=default

	KVPosition (const KVPosition &o)

	KVPosition (Double_t thmin, Double_t thmax, Double_t phmin, Double_t phmax, Double_t dist=0.0)

	KVPosition (KVPosition &&other) noexcept

virtual	~KVPosition ()=default

void	CalculateEstimatedAngularLimits (int N=10000)

Double_t	GetAzimuthalWidth (Double_t phmin=-1., Double_t phimax=-1.) const

void	GetCornerCoordinates (TVector3 *, Double_t=0)

void	GetCornerCoordinatesInOwnFrame (TVector3 *, Double_t=0)

virtual Double_t	GetCosineMaximumMisalignmentAngle () const

virtual Double_t	GetCosTheta () const

virtual TVector3	GetDirection ()

virtual Double_t	GetDistance (void) const

virtual TGeoHMatrix *	GetMatrix () const

virtual Double_t	GetMaximumMisalignmentAngle () const

virtual TVector3	GetNormalIntoShape () const

virtual Double_t	GetPhi () const

Double_t	GetPhiMax () const

Double_t	GetPhiMin () const

virtual void	GetRandomAngles (Double_t &th, Double_t &ph, Option_t *t="isotropic")

virtual TVector3	GetRandomDirection (Option_t *t="isotropic")

TRotation	GetRandomIsotropicRotation ()

virtual TVector3	GetRandomPointOnSurface () const

virtual TGeoBBox *	GetShape () const

virtual Double_t	GetSinTheta () const

virtual Double_t	GetSolidAngle (void) const

virtual Double_t	GetSurfaceArea (int npoints=100000) const

virtual TVector3	GetSurfaceCentre () const

virtual Double_t	GetTheta () const

Double_t	GetThetaMax () const

Double_t	GetThetaMin () const

virtual TVector3	GetVolumeCentre () const

void	GetWidthsFromDimension (Double_t lin_dim)

Bool_t	IsAlignedWith (KVPosition *pos)
	kTRUE if one of the two solid angle elements is completely contained within the other. More...

Bool_t	IsAzimuthallyWiderThan (KVPosition *pos)

Bool_t	IsInPhiRange (const Double_t phi)

Bool_t	IsInPolarRange (const Double_t theta)
	kTRUE if given angle theta is within the polar range of this solid angle element More...

Bool_t	IsOverlappingWith (KVPosition *pos)
	kTRUE if there is at least partial overlap between two solid angle elements More...

Bool_t	IsSmallerThan (KVPosition *pos)
	kTRUE if "this" is entirely contained within "pos" More...

KVPosition &	operator= (KVPosition other)

virtual Bool_t	ROOTGeo () const

virtual void	SetAzimuthalAngle (Double_t ph)

virtual void	SetAzimuthalMinMax (Double_t min, Double_t max)
	Set min and max azimuthal angles and calculate (mean) phi. More...

virtual void	SetAzimuthalWidth (Double_t aw)

void	SetDistance (Double_t d)

virtual void	SetMatrix (const TGeoHMatrix *)
	Set the global transformation matrix for this volume. More...

void	SetPhi (Double_t p)

void	SetPhiMinMax (Double_t min, Double_t max)

virtual void	SetPolarAngle (Double_t th)

virtual void	SetPolarMinMax (Double_t min, Double_t max)
	Set min and max polar angles and calculate (mean) theta. More...

virtual void	SetPolarWidth (Double_t pw)

virtual void	SetShape (TGeoBBox *)

void	SetTheta (Double_t t)

Friends
void	swap (KVPosition &p1, KVPosition &p2)

Constructor & Destructor Documentation

◆ KVPosition() [1/4]

KVPosition::KVPosition ( )

default

◆ KVPosition() [2/4]

KVPosition::KVPosition	(	Double_t	thmin,
		Double_t	thmax,
		Double_t	phmin,
		Double_t	phmax,
		Double_t	dist = `0.0`
	)

Definition at line 39 of file KVPosition.cpp.

◆ ~KVPosition()

virtual KVPosition::~KVPosition ( )

virtualdefault

◆ KVPosition() [3/4]

KVPosition::KVPosition ( const KVPosition & o )

inline

Definition at line 130 of file KVPosition.h.

◆ KVPosition() [4/4]

KVPosition::KVPosition ( KVPosition && other )

inlinenoexcept

Definition at line 138 of file KVPosition.h.

Member Function Documentation

◆ CalculateEstimatedAngularLimits()

void KVPosition::CalculateEstimatedAngularLimits ( int N = 10000 )

For ROOT geometries, perform a Monte-Carlo sampling in order to estimate the min/max polar and azimuthal angles of this volume

Definition at line 294 of file KVPosition.cpp.

◆ GetAzimuthalWidth()

Double_t KVPosition::GetAzimuthalWidth	(	Double_t	phmin = `-1.`,
		Double_t	phmax = `-1.`
	)		const

Calculate azimuthal width taking phi-min as the most anticlockwise point of the element and phi-max the most clockwise. If no arguments are given, width calculated for this object Otherwise, width calculated for given phi-min and phi-max

Examples: ExampleAnalysis_KVEventMixerN_2Body.cpp, and ExampleCorrelationAnalysis.cpp.

Definition at line 590 of file KVPosition.cpp.

◆ GetCornerCoordinates()

void KVPosition::GetCornerCoordinates	(	TVector3 *	corners,
		Double_t	depth = `0`
	)

Fill the array (TVector3 corner[4]) with the coordinates of the 4 'corners' of the solid angle element.

These 'corners' are the points of intersection between the plane defined by the normal to the centre of the solid angle (direction: theta,phi), at a distance fDistance [cm] from the origin, and the four lines starting at the origin with directions (thetamin,phimin), (thetamax,phimin), (thetamax,phimax), (thetamin,phimax).

If optional argument 'depth' [cm] is given, the coordinates are calculated for the plane situated at distance (fDistance+depth) from the origin.

The order of the 4 corners is as follows: corners[3] : theta-min, phi-min corners[2] : theta-max, phi-min corners[1] : theta-max, phi-max corners[0] : theta-min, phi-max

Coordinates are in CENTIMETRES

Definition at line 483 of file KVPosition.cpp.

◆ GetCornerCoordinatesInOwnFrame()

void KVPosition::GetCornerCoordinatesInOwnFrame	(	TVector3 *	corners,
		Double_t	depth = `0`
	)

Like GetCornerCoordinates(), except that the coordinates correspond to a reference frame in which the +ve z-axis goes through the centre of the solid angle

Definition at line 531 of file KVPosition.cpp.

◆ GetCosineMaximumMisalignmentAngle()

virtual Double_t KVPosition::GetCosineMaximumMisalignmentAngle ( ) const

inlinevirtual

Returns: cosine of the maximum angle between all directions from the origin to a point on the surface of this volume and the normal to the volume's surface (i.e. the axis of the volume, along which the nominal thickness is calculated).

The maximum effective thickness of the volume 'seen' from the origin is then \(e/\cos\theta\).

Reimplemented in KVDetector.

Definition at line 291 of file KVPosition.h.

◆ GetCosTheta()

virtual Double_t KVPosition::GetCosTheta ( ) const

inlinevirtual

Reimplemented in KVDetector.

Definition at line 224 of file KVPosition.h.

◆ GetDirection()

TVector3 KVPosition::GetDirection ( )

virtual

Returns a unit vector corresponding to the direction of fTheta, fPhi i.e. the centre of the solid angle element.

Reimplemented in KVDetector.

Definition at line 450 of file KVPosition.cpp.

◆ GetDistance()

virtual Double_t KVPosition::GetDistance ( void ) const

inlinevirtual

Reimplemented in KVDetector.

Definition at line 246 of file KVPosition.h.

◆ GetMatrix()

TGeoHMatrix * KVPosition::GetMatrix ( ) const

virtual

ROOT Geometry * Return global transformation matrix for this detector

Definition at line 746 of file KVPosition.cpp.

◆ GetMaximumMisalignmentAngle()

virtual Double_t KVPosition::GetMaximumMisalignmentAngle ( ) const

inlinevirtual

Returns: the maximum angle [deg] between all directions from the origin to a point on the surface of this volume and the normal to the volume's surface (i.e. the axis of the volume, along which the nominal thickness is calculated).

Reimplemented in KVDetector.

Definition at line 282 of file KVPosition.h.

◆ GetNormalIntoShape()

virtual TVector3 KVPosition::GetNormalIntoShape ( ) const

inlinevirtual

normal to shape, i.e. axis along which shape has its nominal thickness, pointing away from the origin i.e. into the shape

Definition at line 275 of file KVPosition.h.

◆ GetPhi()

virtual Double_t KVPosition::GetPhi ( ) const

inlinevirtual

Reimplemented in KVDetector.

Definition at line 228 of file KVPosition.h.

◆ GetPhiMax()

Double_t KVPosition::GetPhiMax ( ) const

inline

Definition at line 196 of file KVPosition.h.

◆ GetPhiMin()

Double_t KVPosition::GetPhiMin ( ) const

inline

Definition at line 190 of file KVPosition.h.

◆ GetRandomAngles()

void KVPosition::GetRandomAngles	(	Double_t &	th,
		Double_t &	ph,
		Option_t *	t = `"isotropic"`
	)

virtual

Set th and ph to random values between the max and min limits defining the solid angle element. Depending on the optional option string, the direction is either drawn at "random" among the corresponding angles, or "isotropic". By default, the direction is "isotropic".

ROOT Geometry * th and ph correspond to a random position on the detector's entrance window. The "isotropic" option has no effect.

Reimplemented in KVDetector.

Definition at line 238 of file KVPosition.cpp.

◆ GetRandomDirection()

TVector3 KVPosition::GetRandomDirection ( Option_t * t = "isotropic" )

virtual

Returns a unit vector in a random direction corresponding to this detector. Depending on the optional option string, the direction is either drawn at "random" among the corresponding angles, or "isotropic". By default, the direction is "isotropic".

ROOT Geometry * Direction corresponds to a random position on the entrance surface of the volume. The "isotropic" option has no effect.

Reimplemented in KVDetector.

Definition at line 200 of file KVPosition.cpp.

◆ GetRandomIsotropicRotation()

TRotation KVPosition::GetRandomIsotropicRotation ( )

Generates a rotation which, if applied to a unit vector in the Z-direction, will transform it into an isotropically-distributed vector in this angular range.

Definition at line 643 of file KVPosition.cpp.

◆ GetRandomPointOnSurface()

TVector3 KVPosition::GetRandomPointOnSurface ( ) const

virtual

ROOT Geometry * Generate a vector in the world (laboratory) frame from the origin to a random point on the entrance surface of this volume.

It is assumed that the volume was defined in such a way that the entrance window corresponds to the facet in the X-Y plane placed at -dZ.

NOTE: we force the use of TGeoBBox::GetPointsOnFacet. For TGeoArb8, the method has been overridden and does nothing. We use the TGeoBBox method, and then use TGeoShape::Contains to check that the point does actually correspond to the TGeoArb8.

Definition at line 782 of file KVPosition.cpp.

◆ GetShape()

TGeoBBox * KVPosition::GetShape ( ) const

virtual

ROOT Geometry * Return shape of this detector

Definition at line 759 of file KVPosition.cpp.

◆ GetSinTheta()

virtual Double_t KVPosition::GetSinTheta ( ) const

inlinevirtual

Reimplemented in KVDetector.

Definition at line 220 of file KVPosition.h.

◆ GetSolidAngle()

Double_t KVPosition::GetSolidAngle ( void ) const

virtual

Return values of the solid angle (in msr) seen by the geometric ensemble For simple geometries defined by theta_min/max etc., this is exact. For ROOT geometries we calculate the area of the entrance window and divide it by the square of the distance to the detector.

Reimplemented in KVDetector.

Definition at line 554 of file KVPosition.cpp.

◆ GetSurfaceArea()

Double_t KVPosition::GetSurfaceArea ( int npoints = 100000 ) const

virtual

Monte Carlo calculation of entrance surface area for TGeoArb8 shapes Area is calculated as area of bounding box facet multiplied by the ratio between number of random points actually on the shape surface to the number of points npoints generated over the surface of the bounding box facet

npoints is the number of points to test

Definition at line 902 of file KVPosition.cpp.

◆ GetSurfaceCentre()

virtual TVector3 KVPosition::GetSurfaceCentre ( ) const

inlinevirtual

Definition at line 267 of file KVPosition.h.

◆ GetTheta()

virtual Double_t KVPosition::GetTheta ( ) const

inlinevirtual

Reimplemented in KVDetector.

Definition at line 216 of file KVPosition.h.

◆ GetThetaMax()

Double_t KVPosition::GetThetaMax ( ) const

inline

Definition at line 208 of file KVPosition.h.

◆ GetThetaMin()

Double_t KVPosition::GetThetaMin ( ) const

inline

Definition at line 202 of file KVPosition.h.

◆ GetVolumeCentre()

virtual TVector3 KVPosition::GetVolumeCentre ( ) const

inlinevirtual

Definition at line 271 of file KVPosition.h.

◆ GetWidthsFromDimension()

void KVPosition::GetWidthsFromDimension ( Double_t lin_dim )

Calculate azimuthal and polar widths for a square element placed at a given distance from the origin with linear dimension 'lin_dim' (in mm). SetDistance, SetTheta and SetPhi must already have been called.

Definition at line 617 of file KVPosition.cpp.

◆ IsAlignedWith()

Bool_t KVPosition::IsAlignedWith ( KVPosition * pos )

kTRUE if one of the two solid angle elements is completely contained within the other.

Definition at line 382 of file KVPosition.cpp.

◆ IsAzimuthallyWiderThan()

Bool_t KVPosition::IsAzimuthallyWiderThan ( KVPosition * pos )

kTRUE if "this" has larger azimuthal width than "pos". Takes care of cases where the solid angle straddles 0 degrees

Definition at line 433 of file KVPosition.cpp.

◆ IsInPhiRange()

Bool_t KVPosition::IsInPhiRange ( const Double_t phi )

kTRUE if given angle phi is within the azimuthal range of this solid angle element

Definition at line 323 of file KVPosition.cpp.

◆ IsInPolarRange()

Bool_t KVPosition::IsInPolarRange ( const Double_t theta )

kTRUE if given angle theta is within the polar range of this solid angle element

Definition at line 349 of file KVPosition.cpp.

◆ IsOverlappingWith()

Bool_t KVPosition::IsOverlappingWith ( KVPosition * pos )

kTRUE if there is at least partial overlap between two solid angle elements

Definition at line 395 of file KVPosition.cpp.

◆ IsSmallerThan()

Bool_t KVPosition::IsSmallerThan ( KVPosition * pos )

kTRUE if "this" is entirely contained within "pos"

Definition at line 366 of file KVPosition.cpp.

◆ operator=()

KVPosition& KVPosition::operator= ( KVPosition other )

inline

Definition at line 161 of file KVPosition.h.

◆ ROOTGeo()

virtual Bool_t KVPosition::ROOTGeo ( ) const

inlinevirtual

Returns kTRUE if ROOT geometry is used, kFALSE if not

Definition at line 257 of file KVPosition.h.

◆ SetAzimuthalAngle()

void KVPosition::SetAzimuthalAngle ( Double_t ph )

virtual

Sets the azimuthal angle corresponding to the centre of this telescope/solid angle element/etc. If the azimuthal width has been set already (KVPosition::SetAzimuthalWidth), the limits phi-min and phi-max are calculated.

Definition at line 75 of file KVPosition.cpp.

◆ SetAzimuthalMinMax()

void KVPosition::SetAzimuthalMinMax	(	Double_t	min,
		Double_t	max
	)

virtual

Set min and max azimuthal angles and calculate (mean) phi.

Reimplemented in KVINDRADetector.

Definition at line 174 of file KVPosition.cpp.

◆ SetAzimuthalWidth()

void KVPosition::SetAzimuthalWidth ( Double_t aw )

virtual

Set phi_min and phi_max from width (in degrees) If phi is already known, use to set phi_min and phi_max If not, keep relative values (negative) of phi_min and phi_max, to be used when phi is set

Definition at line 147 of file KVPosition.cpp.

◆ SetDistance()

void KVPosition::SetDistance ( Double_t d )

inline

Definition at line 242 of file KVPosition.h.

◆ SetMatrix()

void KVPosition::SetMatrix ( const TGeoHMatrix * m )

virtual

Set the global transformation matrix for this volume.

Definition at line 713 of file KVPosition.cpp.

◆ SetPhi()

void KVPosition::SetPhi ( Double_t p )

inline

Definition at line 238 of file KVPosition.h.

◆ SetPhiMinMax()

void KVPosition::SetPhiMinMax	(	Double_t	min,
		Double_t	max
	)

inline

Definition at line 173 of file KVPosition.h.

◆ SetPolarAngle()

void KVPosition::SetPolarAngle ( Double_t th )

virtual

Sets the polar angle corresponding to the centre of this telescope/solid angle element/etc. If the polar width has been set already (KVPosition::SetPolarWidth), the limits theta-min and theta-max are calculated.

Definition at line 54 of file KVPosition.cpp.

◆ SetPolarMinMax()

void KVPosition::SetPolarMinMax	(	Double_t	min,
		Double_t	max
	)

virtual

Set min and max polar angles and calculate (mean) theta.

Reimplemented in KVINDRADetector.

Definition at line 129 of file KVPosition.cpp.

◆ SetPolarWidth()

void KVPosition::SetPolarWidth ( Double_t pw )

virtual

Set theta_min and theta_max from width (in degrees). If theta is already known, use to set theta_min and theta_max. If not, keep relative values (negative) of theta_min and theta_max, to be used when theta is set

Definition at line 105 of file KVPosition.cpp.

◆ SetShape()

void KVPosition::SetShape ( TGeoBBox * b )

virtual

Set the shape of this volume

Definition at line 729 of file KVPosition.cpp.

◆ SetTheta()

void KVPosition::SetTheta ( Double_t t )

inline

Definition at line 234 of file KVPosition.h.

Friends And Related Function Documentation

◆ swap

void swap	(	KVPosition &	p1,
		KVPosition &	p2
	)

friend

Definition at line 144 of file KVPosition.h.

Detailed Description

Examples of use of KVPosition objects

Public Member Functions

Friends

Constructor & Destructor Documentation

◆ KVPosition() [1/4]

◆ KVPosition() [2/4]

◆ ~KVPosition()

◆ KVPosition() [3/4]

◆ KVPosition() [4/4]

Member Function Documentation

◆ CalculateEstimatedAngularLimits()

◆ GetAzimuthalWidth()

◆ GetCornerCoordinates()

◆ GetCornerCoordinatesInOwnFrame()

◆ GetCosineMaximumMisalignmentAngle()

◆ GetCosTheta()

◆ GetDirection()

◆ GetDistance()

◆ GetMatrix()

◆ GetMaximumMisalignmentAngle()

◆ GetNormalIntoShape()

◆ GetPhi()

◆ GetPhiMax()

◆ GetPhiMin()

◆ GetRandomAngles()

◆ GetRandomDirection()

◆ GetRandomIsotropicRotation()

◆ GetRandomPointOnSurface()

◆ GetShape()

◆ GetSinTheta()

◆ GetSolidAngle()

◆ GetSurfaceArea()

◆ GetSurfaceCentre()

◆ GetTheta()

◆ GetThetaMax()

◆ GetThetaMin()

◆ GetVolumeCentre()

◆ GetWidthsFromDimension()

◆ IsAlignedWith()

◆ IsAzimuthallyWiderThan()

◆ IsInPhiRange()

◆ IsInPolarRange()

◆ IsOverlappingWith()

◆ IsSmallerThan()

◆ operator=()

◆ ROOTGeo()

◆ SetAzimuthalAngle()

◆ SetAzimuthalMinMax()

◆ SetAzimuthalWidth()

◆ SetDistance()

◆ SetMatrix()

◆ SetPhi()

◆ SetPhiMinMax()

◆ SetPolarAngle()

◆ SetPolarMinMax()

◆ SetPolarWidth()

◆ SetShape()

◆ SetTheta()

Friends And Related Function Documentation

◆ swap