TrapezoidalPlaneBounds.cc

#include "DataFormats/GeometrySurface/interface/TrapezoidalPlaneBounds.h"
#include "DataFormats/GeometrySurface/interface/LocalError.h"
#include <cmath>

TrapezoidalPlaneBounds::TrapezoidalPlaneBounds( float be, float te, 
						float a, float t) : 
  hbotedge(be), htopedge(te), hapothem(a), hthickness(t) {

  // pre-compute offset of triangle vertex and tg of (half) opening
  // angle of the trapezoid for faster inside() implementation.

  offset = a * (te+be) / (te-be);  // check sign if te < be !!! 
  tan_a = te / std::abs(offset + a);
}


int TrapezoidalPlaneBounds::yAxisOrientation() const {
  return (hbotedge>htopedge) ? -1 : 1;
}

bool TrapezoidalPlaneBounds::inside( const Local2DPoint& p) const {
  return (std::abs(p.y()) < hapothem) & 
    (std::abs(p.x()) < tan_a*std::abs(p.y()+offset));
}

bool TrapezoidalPlaneBounds::inside( const Local3DPoint& p) const {
  return ((std::abs(p.y()) < hapothem) & (std::abs(p.z()) < hthickness)) && std::abs(p.x()) < tan_a*std::abs(p.y()+offset);
}

bool TrapezoidalPlaneBounds::inside( const Local3DPoint& p,
				     const LocalError& err, float scale) const {
  if (scale>=0 && inside(p)) return true;

  TrapezoidalPlaneBounds tmp( hbotedge + std::sqrt(err.xx())*scale,
			      htopedge + std::sqrt(err.xx())*scale,
			      hapothem + std::sqrt(err.yy())*scale,
			      hthickness);
  return tmp.inside(p);
}
  
bool TrapezoidalPlaneBounds::inside( const Local2DPoint& p, const LocalError& err, float scale) const {
  return Bounds::inside(p,err,scale);
}

float TrapezoidalPlaneBounds::howMuchInside(const Local3DPoint& p, const LocalError& err) const {
   return std::max( 
                   (std::abs(p.y())-hapothem)/std::sqrt(err.yy()),
                   (std::abs(p.x())-tan_a*std::abs(p.y()+offset))/std::sqrt(err.xx())
                  );
}



Bounds* TrapezoidalPlaneBounds::clone() const { 
  return new TrapezoidalPlaneBounds(*this);
}



const std::array<const float, 4> TrapezoidalPlaneBounds::parameters() const { 
  // Same order as geant3 for constructor compatibility
  std::array<const float, 4> vec { { hbotedge, htopedge, hthickness, hapothem } };
  return vec;
}