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IdealObliquePrism.cc

Go to the documentation of this file.

#include "Geometry/CaloGeometry/interface/IdealObliquePrism.h"
#include <math.h>

namespace calogeom {
   
   static GlobalPoint etaPhiR( float eta, float phi, float rad )
   {
      return GlobalPoint( rad*cosf(phi)/coshf(eta) , 
                          rad*sinf(phi)/coshf(eta) ,
                          rad*tanhf(eta)            ) ;
   }
   
   static GlobalPoint etaPhiPerp( float eta, float phi, float perp )  
   {
      return GlobalPoint( perp*cosf(phi) ,
                          perp*sinf(phi) ,
                          perp*sinhf(eta) ) ;
   }

   static GlobalPoint etaPhiZ(float eta, float phi, float z) 
   {
      return GlobalPoint( z*cosf(phi)/sinhf(eta) , 
                          z*sinf(phi)/sinhf(eta) ,
                          z                       ) ;
   }

   const CaloCellGeometry::CornersVec& 
   IdealObliquePrism::getCorners() const
   {
      const CornersVec& co ( CaloCellGeometry::getCorners() ) ;
      if( co.uninitialized() )
      {
         CornersVec& corners ( setCorners() ) ;
         if( dz()>0 ) 
         { 
            /* In this case, the faces are parallel to the zaxis.  
               This implies that all corners will have the same 
               cylindrical radius. 
            */
            const GlobalPoint p      ( getPosition() ) ;
            const float       r_near ( p.perp()/cos(dPhi()) ) ;
            const float       r_far  ( r_near*( ( p.mag() + 2*dz() )/p.mag() ) ) ;
            const float       eta    ( p.eta() ) ;
            const float       phi    ( p.phi() ) ;
            corners[ 0 ] = etaPhiPerp( eta + dEta() , phi + dPhi() , r_near ) ; // (+,+,near)
            corners[ 1 ] = etaPhiPerp( eta + dEta() , phi - dPhi() , r_near ) ; // (+,-,near)
            corners[ 2 ] = etaPhiPerp( eta - dEta() , phi - dPhi() , r_near ) ; // (-,-,near)
            corners[ 3 ] = etaPhiPerp( eta - dEta() , phi + dPhi() , r_near ) ; // (-,+,near)
            corners[ 4 ] = etaPhiPerp( eta + dEta() , phi + dPhi() , r_far ) ; // (+,+,far)
            corners[ 5 ] = etaPhiPerp( eta + dEta() , phi - dPhi() , r_far ) ; // (+,-,far)
            corners[ 6 ] = etaPhiPerp( eta - dEta() , phi - dPhi() , r_far ) ; // (-,-,far)
            corners[ 7 ] = etaPhiPerp( eta - dEta() , phi + dPhi() , r_far ) ; // (-,+,far)
         } 
         else 
         {
            /* In this case, the faces are perpendicular to the zaxis.  
               This implies that all corners will have the same 
               z-dimension. 
            */
            const GlobalPoint p      ( getPosition() ) ;
            const float       z_near ( p.z() ) ;
            const float       mag    ( p.mag() ) ;
            const float       z_far  ( z_near*( 1 - 2*dz()/mag ) ) ; // negative to correct sign
            const float       eta    ( p.eta() ) ;
            const float       phi    ( p.phi() ) ;
            
            corners[ 0 ] = etaPhiZ( eta + dEta(), phi + dPhi(), z_near ) ; // (+,+,near)
            corners[ 1 ] = etaPhiZ( eta + dEta(), phi - dPhi(), z_near ) ; // (+,-,near)
            corners[ 2 ] = etaPhiZ( eta - dEta(), phi - dPhi(), z_near ) ; // (-,-,near)
            corners[ 3 ] = etaPhiZ( eta - dEta(), phi + dPhi(), z_near ) ; // (-,+,near)
            corners[ 4 ] = etaPhiZ( eta + dEta(), phi + dPhi(), z_far  ) ; // (+,+,far)
            corners[ 5 ] = etaPhiZ( eta + dEta(), phi - dPhi(), z_far  ) ; // (+,-,far)
            corners[ 6 ] = etaPhiZ( eta - dEta(), phi - dPhi(), z_far  ) ; // (-,-,far)
            corners[ 7 ] = etaPhiZ( eta - dEta(), phi + dPhi(), z_far  ) ; // (-,+,far)

         }
      }
      return co ;
   }

   bool 
   IdealObliquePrism::inside( const GlobalPoint& point ) const 
   {
      // first check eta/phi
      bool is_inside ( false ) ;

      const GlobalPoint& face ( getPosition() ) ;

      // eta
      if( fabs( point.eta() - face.eta() ) <= dEta()  &&
          fabs( point.phi() - face.phi() ) <= dPhi()     )
      {
         // distance (trickier)
         GlobalPoint face2 ( etaPhiR( face.eta(), 
                                      face.phi(), 
                                      face.mag() + 2*fabs( dz() ) ) );
         if( dz() > 0 ) 
         { // 
            const float projection ( point.perp()*cos( point.phi() - face.phi() ) ) ;
            is_inside = ( projection >= face.perp() &&
                          projection <= face2.perp()    ) ;
         } 
         else 
         { // here, it is just a Z test.
            is_inside = ( ( ( face.z()<0 ) ? ( point.z()<=face.z()  ) :
                            ( point.z()>=face.z()  ) ) && // "front" face
                          ( ( face.z()<0 ) ? ( point.z()>=face2.z() ) :
                            ( point.z()<=face2.z() ) ) ); // "back" face
         }
      }
      return is_inside;
   }

   std::ostream& operator<<( std::ostream& s, const IdealObliquePrism& cell ) 
   {
      s << "Center: " <<  cell.getPosition() << std::endl ;
      s << "dEta = " << cell.dEta() << ", dPhi = " << cell.dPhi() << ", dz = " << cell.dz() << std::endl ;
      return s;
}

}

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