genie::geometry::FidCylinder Class Reference

#include <FidShape.h>

Inheritance diagram for genie::geometry::FidCylinder:

Collaboration diagram for genie::geometry::FidCylinder:

Public Member Functions
	FidCylinder (const TVector3 &base, const TVector3 &axis, Double_t radius, const PlaneParam &cap1, const PlaneParam &cap2)
RayIntercept	Intercept (const TVector3 &start, const TVector3 &dir) const
RayIntercept	InterceptUncapped (const TVector3 &start, const TVector3 &dir) const
void	ConvertMaster2Top (const ROOTGeomAnalyzer *rgeom)
void	Print (std::ostream &stream) const
Public Member Functions inherited from genie::geometry::FidShape
	FidShape ()
virtual	~FidShape ()

Protected Attributes
TVector3	fCylBase
TVector3	fCylAxis
	base point on cylinder axis More...
Double_t	fCylRadius
	direction cosines of cylinder axis More...
PlaneParam	fCylCap1
	radius of cylinder More...
PlaneParam	fCylCap2
	define a plane for 1st cylinder cap More...

Detailed Description

Definition at line 118 of file FidShape.h.

Constructor & Destructor Documentation

genie::geometry::FidCylinder::FidCylinder ( const TVector3 &  base, const TVector3 &  axis, Double_t  radius, const PlaneParam &  cap1, const PlaneParam &  cap2  )

inline

Definition at line 120 of file FidShape.h.

   : fCylBase(base), fCylAxis(axis), fCylRadius(radius), fCylCap1(cap1), fCylCap2(cap2) { ; }

Member Function Documentation

void FidCylinder::ConvertMaster2Top ( const ROOTGeomAnalyzer *  rgeom )

virtual

derived classes must implement the ConvertMaster2Top() method which transforms the shape specification from master coordinates to "top vol"

Implements genie::geometry::FidShape.

Definition at line 194 of file FidShape.cxx.

References genie::geometry::ROOTGeomAnalyzer::Master2Top(), and genie::geometry::ROOTGeomAnalyzer::Master2TopDir().

{
  rgeom->Master2Top(fCylBase);
  rgeom->Master2TopDir(fCylAxis);
  fCylCap1.ConvertMaster2Top(rgeom);
  fCylCap2.ConvertMaster2Top(rgeom);
}

RayIntercept FidCylinder::Intercept ( const TVector3 &  start, const TVector3 &  dir  ) const

virtual

derived classes must implement the Intercept() method which calculates the entry/exit point of a ray w/ the shape

Implements genie::geometry::FidShape.

Definition at line 159 of file FidShape.cxx.

References genie::geometry::RayIntercept::fDistIn, genie::geometry::RayIntercept::fDistOut, genie::geometry::RayIntercept::fIsHit, genie::geometry::RayIntercept::fSurfIn, genie::geometry::RayIntercept::fSurfOut, genie::geometry::PlaneParam::IsValid(), genie::geometry::PlaneParam::Vd(), and genie::geometry::PlaneParam::Vn().

{
  // A new neutrino ray has been set, calculate the entrance/exit distances.

  RayIntercept intercept = InterceptUncapped(start,dir);  // find where ray hits the infinite cylinder
  // trim this down by applying the end caps
  if ( ! intercept.fIsHit ) return intercept;
  for ( int icap=1; icap <= 2; ++icap ) {
    const PlaneParam& cap = (icap==1) ? fCylCap1 : fCylCap2;
    if ( ! cap.IsValid() ) continue;
    Double_t vd = cap.Vd(dir);
    Double_t vn = cap.Vn(start);
    //std::cout << "FidCyl::Intercept cap " << icap
    //          << " vd " << vd << " vn " << vn;
    if ( vd == 0.0 ) { // parallel to surface, is it on the right side?
      //std::cout << " vd=0, vn " << ((vn>0)?"wrong":"right") << "side " << std::endl;
      if ( vn > 0 ) { intercept.fIsHit = false; break; } // wrong side
    } else {
      Double_t t = -vn / vd;
      //std::cout << " t " << t << " in/out "
      //          << intercept.fDistIn << "/" << intercept.fDistOut << std::endl;
      if ( vd < 0.0 ) { // t is the entering point
        if ( t > intercept.fDistIn  )
          { intercept.fDistIn  = t;  intercept.fSurfIn  = 1; }
      } else { // t is the exiting point
        if ( t < intercept.fDistOut )
          { intercept.fDistOut = t;  intercept.fSurfOut = 1; }
      }
    }
  }
  if ( intercept.fDistIn > intercept.fDistOut ) intercept.fIsHit = false;
  return intercept;
}

RayIntercept FidCylinder::InterceptUncapped	(	const TVector3 &	start,
		const TVector3 &	dir
	)		const

Definition at line 113 of file FidShape.cxx.

References genie::geometry::RayIntercept::fDistIn, genie::geometry::RayIntercept::fDistOut, genie::geometry::RayIntercept::fIsHit, genie::geometry::RayIntercept::fSurfIn, genie::geometry::RayIntercept::fSurfOut, and genie::units::s.

{
  // A new neutrino ray has been set, calculate the entrance/exit distances.
  // This sets fDistIn/fDistOut for an infinite cylinder
  // Take as "hit" if the ray is parallel to the axis but inside the radius
  RayIntercept intercept;

  TVector3 rc   = start - fCylBase;
  TVector3 n    = dir.Cross(fCylAxis);
  Double_t len  = n.Mag();
  Double_t dist = 0;
  if ( len == 0.0 ) {
    // ray is parallel to axis
    dist = rc.Dot(fCylAxis);
    TVector3 d = rc - dist*fCylAxis;
    dist = d.Mag();
    //LOG("GeomVolSel", pNOTICE) << " len = " << len << " is parallel, dist " << dist << ", " << fCylRadius;
    if ( dist <= fCylRadius ) {
      intercept.fIsHit   = true;  // inside is considered a hit
      intercept.fSurfIn  = 0;
      intercept.fSurfOut = 0;
    }
    return intercept;
  }
  // ray is not parallel
  if ( len != 1.0 ) n.SetMag(1.);  // normalize if it isn't already
  dist = TMath::Abs(rc.Dot(n));    // closest approach distance
  //LOG("GeomVolSel", pNOTICE) << " len = " << len << " not parallel, dist " << dist << ", " << fCylRadius;
  if ( dist <= fCylRadius ) {
    intercept.fIsHit = true; // yes, it hits
    intercept.fSurfIn  = 0;
    intercept.fSurfOut = 0;
    TVector3 o = rc.Cross(fCylAxis);
    Double_t t = - o.Dot(n)/len;
    o = n.Cross(fCylAxis);
    o.SetMag(1.);
    Double_t s = TMath::Abs( TMath::Sqrt(fCylRadius*fCylRadius-dist*dist) /
                             dir.Dot(o)    );
    intercept.fDistIn  = t - s;
    intercept.fDistOut = t + s;
    //LOG("GeomVolSel", pNOTICE) << " hits, t = " << t << " s = " << s;
  }
  return intercept;
}

void FidCylinder::Print ( std::ostream &  stream ) const

virtual

Implements genie::geometry::FidShape.

Definition at line 203 of file FidShape.cxx.

{
  stream << "FidCylinder @ ["
         << fCylBase.X() << ","
         << fCylBase.Y() << ","
         << fCylBase.Z() << "]  dir ["
         << fCylAxis.X() << ","
         << fCylAxis.Y() << ","
         << fCylAxis.Z() << "]  r = " << fCylRadius;
  stream << " cap1=" << fCylCap1 << " cap2=" << fCylCap2;
}

Member Data Documentation

TVector3 genie::geometry::FidCylinder::fCylAxis

protected

base point on cylinder axis

Definition at line 130 of file FidShape.h.

TVector3 genie::geometry::FidCylinder::fCylBase

protected

Definition at line 129 of file FidShape.h.

PlaneParam genie::geometry::FidCylinder::fCylCap1

protected

radius of cylinder

Definition at line 132 of file FidShape.h.

PlaneParam genie::geometry::FidCylinder::fCylCap2

protected

define a plane for 1st cylinder cap

Definition at line 133 of file FidShape.h.

Double_t genie::geometry::FidCylinder::fCylRadius

protected

direction cosines of cylinder axis

Definition at line 131 of file FidShape.h.

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

• FidShape.h
• FidShape.cxx