db/dfa/VolumeMaterialInteraction_8hpp_source.html

// This file is part of the Acts project.

//

// Copyright (C) 2019 CERN for the benefit of the Acts project

//

// This Source Code Form is subject to the terms of the Mozilla Public

// License, v. 2.0. If a copy of the MPL was not distributed with this

// file, You can obtain one at http://mozilla.org/MPL/2.0/.


#pragma once


#include "Acts/Geometry/TrackingVolume.hpp"

#include "Acts/Material/ISurfaceMaterial.hpp"

#include "Acts/Material/MaterialProperties.hpp"

#include "Acts/Surfaces/Surface.hpp"


namespace Acts {

namespace detail {

struct VolumeMaterialInteraction {

  const TrackingVolume* volume;


  const Vector3D pos;

  const double time;

  const Vector3D dir;

  const double momentum;

  const double q;

  const double qOverP;


  const double mass;

  const int pdg;

  const bool performCovarianceTransport;

  const NavigationDirection nav;


  MaterialProperties slab;

  double pathCorrection;


  double variancePhi = 0.;

  double varianceTheta = 0.;

  double varianceQoverP = 0.;


  double Eloss = 0.;

  double nextP;


  template <typename propagator_state_t, typename stepper_t>

  VolumeMaterialInteraction(const TrackingVolume* vVolume,

                            const propagator_state_t& state,

                            const stepper_t& stepper)

      : volume(vVolume),

        pos(stepper.position(state.stepping)),

        time(stepper.time(state.stepping)),

        dir(stepper.direction(state.stepping)),

        momentum(stepper.momentum(state.stepping)),

        q(stepper.charge(state.stepping)),

        qOverP(q / momentum),

        mass(state.options.mass),

        pdg(state.options.absPdgCode),

        performCovarianceTransport(state.stepping.covTransport),

        nav(state.stepping.navDir),

        variancePhi(state.stepping.cov(ePHI, ePHI)),

        varianceTheta(state.stepping.cov(eTHETA, eTHETA)),

        varianceQoverP(state.stepping.cov(eQOP, eQOP)) {}


  template <typename propagator_state_t>

  bool evaluateMaterialProperties(const propagator_state_t& state) {

    pathCorrection = 0;

    slab = MaterialProperties(

        state.navigation.currentVolume->volumeMaterial()->material(pos),

        1);  // state.stepping.StepSize

    return slab;

  }

};

}  // namespace detail

}  // end of namespace Acts