EIC code displayed by LXR master/​acts/​Core/​include/​Acts/​Surfaces/​SurfaceArray.hpp	Source navigation Diff markup Identifier search General search
	Version: master test Revert   Change

File indexing completed on 2025-10-28 07:53:51

 // This file is part of the ACTS project.
 //
 // Copyright (C) 2016 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 https://mozilla.org/MPL/2.0/.
 
 #pragma once
 
 #include "Acts/Definitions/Algebra.hpp"
 #include "Acts/Geometry/GeometryContext.hpp"
 #include "Acts/Surfaces/BoundaryTolerance.hpp"
 #include "Acts/Surfaces/CylinderBounds.hpp"
 #include "Acts/Surfaces/RegularSurface.hpp"
 #include "Acts/Surfaces/Surface.hpp"
 #include "Acts/Utilities/AnyGridView.hpp"
 #include "Acts/Utilities/AxisDefinitions.hpp"
 #include "Acts/Utilities/Grid.hpp"
 #include "Acts/Utilities/IAxis.hpp"
 #include "Acts/Utilities/Intersection.hpp"
 
 #include <iostream>
 #include <limits>
 #include <vector>
 
 namespace Acts {
 
 using SurfaceVector = std::vector<const Surface*>;
 
 /// @brief Provides Surface binning in 2 dimensions
 ///
 /// Uses @c Grid under the hood to implement the storage and lookup
 /// Contains a lookup struct which talks to the @c Grid
 /// and performs utility actions. This struct needs to be initialised
 /// externally and passed to @c SurfaceArray on construction.
 class SurfaceArray {
  public:
   /// @brief Base interface for all surface lookups.
   struct ISurfaceGridLookup {
     /// @brief Fill provided surfaces into the contained @c Grid.
     /// @param gctx The current geometry context object, e.g. alignment
     /// @param surfaces Input surface pointers
     virtual void fill(const GeometryContext& gctx,
                       const SurfaceVector& surfaces) = 0;
 
     /// @brief Performs lookup at @c pos and returns bin content as const
     /// reference
     /// @param position Lookup position
     /// @param direction Lookup direction
     /// @return @c SurfaceVector at given bin
     virtual const SurfaceVector& lookup(const Vector3& position,
                                         const Vector3& direction) const = 0;
 
     /// @brief Performs lookup at global bin and returns bin content as
     /// reference
     /// @param bin Global lookup bin
     /// @return @c SurfaceVector at given bin
     virtual SurfaceVector& lookup(std::size_t bin) = 0;
 
     /// @brief Performs lookup at global bin and returns bin content as const
     /// reference
     /// @param bin Global lookup bin
     /// @return @c SurfaceVector at given bin
     virtual const SurfaceVector& lookup(std::size_t bin) const = 0;
 
     /// @brief Performs a lookup at @c pos, but returns neighbors as well
     ///
     /// @param position Lookup position
     /// @param direction Lookup direction
     /// @return @c SurfaceVector at given bin. Copy of all bins selected
     virtual const SurfaceVector& neighbors(const Vector3& position,
                                            const Vector3& direction) const = 0;
 
     /// @brief Returns the total size of the grid (including under/overflow
     /// bins)
     /// @return Size of the grid data structure
     virtual std::size_t size() const = 0;
 
     /// @brief Gets the center position of bin @c bin in global coordinates
     /// @param bin the global bin index
     /// @return The bin center
     virtual Vector3 getBinCenter(std::size_t bin) const = 0;
 
     /// @brief Returns copies of the axes used in the grid as @c AnyAxis
     /// @return The axes
     /// @note This returns copies. Use for introspection and querying.
     virtual std::vector<const IAxis*> getAxes() const = 0;
 
     /// @brief Get a view of the grid for inspection
     /// @return Optional grid view containing surface vectors
     virtual std::optional<AnyGridConstView<SurfaceVector>> getGridView()
         const = 0;
 
     /// @brief Get the representative surface used for this lookup
     /// @return Surface pointer
     virtual const Surface* surfaceRepresentation() const = 0;
 
     /// @brief Checks if global bin is valid
     /// @param bin the global bin index
     /// @return bool if the bin is valid
     /// @note Valid means that the index points to a bin which is not a under
     ///       or overflow bin or out of range in any axis.
     virtual bool isValidBin(std::size_t bin) const = 0;
 
     /// @brief The binning values described by this surface grid lookup
     /// They are in order of the axes (optional) and empty for eingle lookups
     /// @return Vector of axis directions for binning
     virtual std::vector<AxisDirection> binningValues() const { return {}; };
 
     /// Pure virtual destructor
     virtual ~ISurfaceGridLookup() = 0;
   };
 
   /// @brief Lookup helper which encapsulates a @c Grid
   /// @tparam Axes The axes used for the grid
   template <class Axis1, class Axis2>
   struct SurfaceGridLookup : ISurfaceGridLookup {
     using Grid_t = Grid<SurfaceVector, Axis1, Axis2>;
 
     /// Construct a surface grid lookup
     /// @param representative The surface which is used as representative
     /// @param tolerance The tolerance used for intersection checks
     /// @param axes The axes used for the grid
     /// @param bValues Optional vector of axis directions for binning
     SurfaceGridLookup(std::shared_ptr<RegularSurface> representative,
                       double tolerance, std::tuple<Axis1, Axis2> axes,
                       std::vector<AxisDirection> bValues = {})
         : m_representative(std::move(representative)),
           m_tolerance(tolerance),
           m_grid(std::move(axes)),
           m_binValues(std::move(bValues)) {
       m_neighborMap.resize(m_grid.size());
     }
 
     /// @brief Fill provided surfaces into the contained @c Grid.
     ///
     /// This is done by iterating, accessing the referencePosition, lookup
     /// and append.
     /// Also populates the neighbor map by combining the filled bins of
     /// all bins around a given one.
     ///
     /// @param gctx The current geometry context object, e.g. alignment
     /// @param surfaces Input surface pointers
     void fill(const GeometryContext& gctx,
               const SurfaceVector& surfaces) override {
       for (const Surface* surface : surfaces) {
         const std::size_t globalBin = fillSurfaceToBinMapping(gctx, *surface);
         if (globalBin == 0) {
           continue;
         }
 
         fillBinToSurfaceMapping(gctx, *surface, globalBin);
       }
 
       populateNeighborCache();
     }
 
     const SurfaceVector& lookup(const Vector3& position,
                                 const Vector3& direction) const override {
       return m_grid.at(findGlobalBin(position, direction,
                                      std::numeric_limits<double>::infinity()));
     }
 
     /// @brief Performs lookup at global bin and returns bin content as
     /// reference
     /// @param bin Global lookup bin
     /// @return @c SurfaceVector at given bin
     SurfaceVector& lookup(std::size_t bin) override { return m_grid.at(bin); }
 
     /// @brief Performs lookup at global bin and returns bin content as const
     /// reference
     /// @param bin Global lookup bin
     /// @return @c SurfaceVector at given bin
     const SurfaceVector& lookup(std::size_t bin) const override {
       return m_grid.at(bin);
     }
 
     /// @brief Performs a lookup at @c pos, but returns neighbors as well
     ///
     /// @param position Lookup position
     /// @param direction Lookup direction
     /// @return @c SurfaceVector at given bin. Copy of all bins selected
     const SurfaceVector& neighbors(const Vector3& position,
                                    const Vector3& direction) const override {
       return m_neighborMap.at(findGlobalBin(
           position, direction, std::numeric_limits<double>::infinity()));
     }
 
     /// @brief Returns the total size of the grid (including under/overflow
     /// bins)
     /// @return Size of the grid data structure
     std::size_t size() const override { return m_grid.size(); }
 
     /// @brief The binning values described by this surface grid lookup
     /// They are in order of the axes
     /// @return Vector of axis directions for binning
     std::vector<AxisDirection> binningValues() const override {
       return m_binValues;
     }
 
     /// @brief Gets the center position of bin @c bin in global coordinates
     /// @param bin the global bin index
     /// @return The bin center
     Vector3 getBinCenter(std::size_t bin) const override {
       GeometryContext gctx;
       return getBinCenterImpl(gctx, bin);
     }
 
     /// @brief Returns copies of the axes used in the grid as @c AnyAxis
     /// @return The axes
     /// @note This returns copies. Use for introspection and querying.
     std::vector<const IAxis*> getAxes() const override {
       auto arr = m_grid.axes();
       return std::vector<const IAxis*>(arr.begin(), arr.end());
     }
 
     std::optional<AnyGridConstView<SurfaceVector>> getGridView()
         const override {
       return AnyGridConstView<SurfaceVector>{m_grid};
     }
 
     const Surface* surfaceRepresentation() const override {
       return m_representative.get();
     }
 
     /// @brief Checks if global bin is valid
     /// @param bin the global bin index
     /// @return bool if the bin is valid
     /// @note Valid means that the index points to a bin which is not a under
     ///       or overflow bin or out of range in any axis.
     bool isValidBin(std::size_t bin) const override {
       std::array<std::size_t, 2> indices = m_grid.localBinsFromGlobalBin(bin);
       std::array<std::size_t, 2> nBins = m_grid.numLocalBins();
       for (std::size_t i = 0; i < indices.size(); ++i) {
         std::size_t idx = indices.at(i);
         if (idx <= 0 || idx >= nBins.at(i) + 1) {
           return false;
         }
       }
       return true;
     }
 
    private:
     /// map surface center to grid
     std::size_t fillSurfaceToBinMapping(const GeometryContext& gctx,
                                         const Surface& surface) {
       const Vector3 pos = surface.referencePosition(gctx, AxisDirection::AxisR);
       const Vector3 normal = m_representative->normal(gctx, pos);
       const std::size_t globalBin = findGlobalBin(pos, normal, m_tolerance);
       if (globalBin != 0) {
         m_grid.at(globalBin).push_back(&surface);
       }
       return globalBin;
     };
 
     /// flood fill neighboring bins given a starting bin
     void fillBinToSurfaceMapping(const GeometryContext& gctx,
                                  const Surface& surface, std::size_t startBin) {
       const std::array<std::size_t, 2> startIndices =
           m_grid.localBinsFromGlobalBin(startBin);
       const auto startNeighborIndices =
           m_grid.neighborHoodIndices(startIndices, 1u);
 
       std::set<std::size_t> visited({startBin});
       std::vector<std::size_t> queue(startNeighborIndices.begin(),
                                      startNeighborIndices.end());
 
       while (!queue.empty()) {
         const std::size_t current = queue.back();
         queue.pop_back();
         if (visited.contains(current)) {
           continue;
         }
 
         const std::array<std::size_t, 2> currentIndices =
             m_grid.localBinsFromGlobalBin(current);
         visited.insert(current);
 
         const std::array<double, 2> gridLocal =
             m_grid.binCenter(currentIndices);
         const Vector2 surfaceLocal = gridToSurfaceLocal(gridLocal);
         const Vector3 normal = m_representative->normal(gctx, surfaceLocal);
         const Vector3 global =
             m_representative->localToGlobal(gctx, surfaceLocal, normal);
 
         const Intersection3D intersection =
             surface.intersect(gctx, global, normal, BoundaryTolerance::None())
                 .closest();
         if (!intersection.isValid() ||
             std::abs(intersection.pathLength()) > m_tolerance) {
           continue;
         }
         m_grid.at(current).push_back(&surface);
 
         const auto neighborIndices =
             m_grid.neighborHoodIndices(currentIndices, 1u);
         queue.insert(queue.end(), neighborIndices.begin(),
                      neighborIndices.end());
       }
     };
 
     void populateNeighborCache() {
       // calculate neighbors for every bin and store in map
       for (std::size_t i = 0; i < m_grid.size(); i++) {
         if (!isValidBin(i)) {
           continue;
         }
         const std::array<std::size_t, 2> indices =
             m_grid.localBinsFromGlobalBin(i);
         std::vector<const Surface*>& neighbors = m_neighborMap.at(i);
         neighbors.clear();
 
         for (std::size_t idx : m_grid.neighborHoodIndices(indices, 1u)) {
           const std::vector<const Surface*>& binContent = m_grid.at(idx);
           std::copy(binContent.begin(), binContent.end(),
                     std::back_inserter(neighbors));
         }
 
         std::ranges::sort(neighbors);
         auto last = std::ranges::unique(neighbors);
         neighbors.erase(last.begin(), last.end());
         neighbors.shrink_to_fit();
       }
     }
 
     Vector3 getBinCenterImpl(const GeometryContext& gctx,
                              std::size_t bin) const {
       const std::array<double, 2> gridLocal =
           m_grid.binCenter(m_grid.localBinsFromGlobalBin(bin));
       const Vector2 surfaceLocal = gridToSurfaceLocal(gridLocal);
       return m_representative->localToGlobal(gctx, surfaceLocal);
     }
 
     const CylinderBounds* getCylinderBounds() const {
       return dynamic_cast<const CylinderBounds*>(&m_representative->bounds());
     }
 
     Vector2 gridToSurfaceLocal(std::array<double, 2> gridLocal) const {
       Vector2 surfaceLocal = Eigen::Map<Vector2>(gridLocal.data());
       if (const CylinderBounds* bounds = getCylinderBounds();
           bounds != nullptr) {
         surfaceLocal[0] *= bounds->get(CylinderBounds::eR);
       }
       return surfaceLocal;
     }
     std::array<double, 2> surfaceToGridLocal(Vector2 local) const {
       std::array<double, 2> gridLocal = {local[0], local[1]};
       if (const CylinderBounds* bounds = getCylinderBounds();
           bounds != nullptr) {
         gridLocal[0] /= bounds->get(CylinderBounds::eR);
       }
       return gridLocal;
     }
 
     std::size_t findGlobalBin(const Vector3& position, const Vector3& direction,
                               double tolerance) const {
       GeometryContext gctx;
 
       const Intersection3D intersection =
           m_representative
               ->intersect(gctx, position, direction,
                           BoundaryTolerance::Infinite())
               .closest();
       if (!intersection.isValid() ||
           std::abs(intersection.pathLength()) > tolerance) {
         return 0;  // overflow bin
       }
       const Vector2 surfaceLocal =
           m_representative
               ->globalToLocal(gctx, intersection.position(), direction)
               .value();
       const std::array<double, 2> gridLocal = surfaceToGridLocal(surfaceLocal);
       return m_grid.globalBinFromPosition(gridLocal);
     }
 
     std::shared_ptr<RegularSurface> m_representative;
     double m_tolerance{};
     Grid_t m_grid;
     std::vector<AxisDirection> m_binValues;
     std::vector<SurfaceVector> m_neighborMap;
   };
 
   /// @brief Lookup implementation which wraps one element and always returns
   ///        this element when lookup is called
   struct SingleElementLookup : ISurfaceGridLookup {
     /// @brief Default constructor.
     /// @param element the one and only element.
     explicit SingleElementLookup(SurfaceVector::value_type element)
         : m_element({element}) {}
 
     /// @brief Default constructor.
     /// @param elements the surfaces that are provided through a single lookup
     explicit SingleElementLookup(const SurfaceVector& elements)
         : m_element(elements) {}
 
     /// @brief Lookup, always returns @c element
     /// @return reference to vector containing only @c element
     const SurfaceVector& lookup(const Vector3& /*position*/,
                                 const Vector3& /*direction*/) const override {
       return m_element;
     }
 
     /// @brief Lookup, always returns @c element
     /// @return reference to vector containing only @c element
     SurfaceVector& lookup(std::size_t /*bin*/) override { return m_element; }
 
     /// @brief Lookup, always returns @c element
     /// @return reference to vector containing only @c element
     const SurfaceVector& lookup(std::size_t /*bin*/) const override {
       return m_element;
     }
 
     /// @brief Lookup, always returns @c element
     /// @return reference to vector containing only @c element
     const SurfaceVector& neighbors(
         const Vector3& /*position*/,
         const Vector3& /*direction*/) const override {
       return m_element;
     }
 
     /// @brief returns 1
     /// @return 1
     std::size_t size() const override { return 1; }
 
     /// @brief Gets the bin center, but always returns (0, 0, 0)
     /// @return (0, 0, 0)
     Vector3 getBinCenter(std::size_t /*bin*/) const override {
       return Vector3(0, 0, 0);
     }
 
     /// @brief Returns an empty vector of @c AnyAxis
     /// @return empty vector
     std::vector<const IAxis*> getAxes() const override { return {}; }
 
     std::optional<AnyGridConstView<SurfaceVector>> getGridView()
         const override {
       return std::nullopt;
     }
 
     const Surface* surfaceRepresentation() const override { return nullptr; }
 
     /// @brief Comply with concept and provide fill method
     /// @note Does nothing
     void fill(const GeometryContext& /*gctx*/,
               const SurfaceVector& /*surfaces*/) override {}
 
     /// @brief Returns if the bin is valid (it is)
     /// @return always true
     bool isValidBin(std::size_t /*bin*/) const override { return true; }
 
    private:
     SurfaceVector m_element;
   };
 
   /// @brief Default constructor which takes a @c SurfaceLookup and a vector of
   /// surfaces
   /// @param gridLookup The grid storage. @c SurfaceArray does not fill it on
   /// its own
   /// @param surfaces The input vector of surfaces. This is only for
   /// bookkeeping, so we can ask
   /// @param transform Optional additional transform for this SurfaceArray
   explicit SurfaceArray(std::unique_ptr<ISurfaceGridLookup> gridLookup,
                         std::vector<std::shared_ptr<const Surface>> surfaces,
                         const Transform3& transform = Transform3::Identity());
 
   /// @brief Constructor with a single surface
   /// @param srf The one and only surface
   explicit SurfaceArray(std::shared_ptr<const Surface> srf);
 
   /// @brief Get all surfaces in bin given by position @p pos.
   /// @param position the lookup position
   /// @param direction the lookup direction
   /// @return const reference to @c SurfaceVector contained in bin at that
   /// position
   const SurfaceVector& at(const Vector3& position,
                           const Vector3& direction) const {
     return p_gridLookup->lookup(position, direction);
   }
 
   /// @brief Get all surfaces in bin given by global bin index @p bin.
   /// @param bin the global bin index
   /// @return reference to @c SurfaceVector contained in bin
   SurfaceVector& at(std::size_t bin) { return p_gridLookup->lookup(bin); }
 
   /// @brief Get all surfaces in bin given by global bin index.
   /// @param bin the global bin index
   /// @return const reference to @c SurfaceVector contained in bin
   const SurfaceVector& at(std::size_t bin) const {
     return p_gridLookup->lookup(bin);
   }
 
   /// @brief Get all surfaces in bin at @p pos and its neighbors
   /// @param position The position to lookup
   /// @param direction The direction to lookup
   /// @return Merged @c SurfaceVector of neighbors and nominal
   /// @note The @c SurfaceVector will be combined. For technical reasons, the
   ///       different bin content vectors have to be copied, so the resulting
   ///       vector contains copies.
   const SurfaceVector& neighbors(const Vector3& position,
                                  const Vector3& direction) const {
     return p_gridLookup->neighbors(position, direction);
   }
 
   /// @brief Get the size of the underlying grid structure including
   /// under/overflow bins
   /// @return the size
   std::size_t size() const { return p_gridLookup->size(); }
 
   /// @brief Get the center of the bin identified by global bin index @p bin
   /// @param bin the global bin index
   /// @return Center position of the bin in global coordinates
   Vector3 getBinCenter(std::size_t bin) const {
     return p_gridLookup->getBinCenter(bin);
   }
 
   /// @brief Get all surfaces attached to this @c SurfaceArray
   /// @return Reference to @c SurfaceVector containing all surfaces
   /// @note This does not reflect the actual state of the grid. It only
   ///       returns what was given in the constructor, without any checks
   ///       if that is actually what's in the grid.
   const SurfaceVector& surfaces() const { return m_surfacesRawPointers; }
 
   /// @brief Get vector of axes spanning the grid as @c AnyAxis
   /// @return vector of @c AnyAxis
   /// @note The axes in the vector are copies. Only use for introspection and
   ///       querying.
   std::vector<const IAxis*> getAxes() const { return p_gridLookup->getAxes(); }
 
   /// @brief Checks if global bin is valid
   /// @param bin the global bin index
   /// @return bool if the bin is valid
   /// @note Valid means that the index points to a bin which is not a under
   ///       or overflow bin or out of range in any axis.
   bool isValidBin(std::size_t bin) const {
     return p_gridLookup->isValidBin(bin);
   }
 
   /// Get the transform of this surface array.
   /// @return Reference to the transformation matrix
   const Transform3& transform() const { return m_transform; }
 
   /// @brief The binning values described by this surface grid lookup
   /// They are in order of the axes
   /// @return Vector of axis directions for binning
   std::vector<AxisDirection> binningValues() const {
     return p_gridLookup->binningValues();
   };
 
   /// @brief String representation of this @c SurfaceArray
   /// @param gctx The current geometry context object, e.g. alignment
   /// @param sl Output stream to write to
   /// @return the output stream given as @p sl
   std::ostream& toStream(const GeometryContext& gctx, std::ostream& sl) const;
 
   /// Return the lookup object
   /// @return Reference to the surface grid lookup interface
   const ISurfaceGridLookup& gridLookup() const { return *p_gridLookup; }
 
  private:
   std::unique_ptr<ISurfaceGridLookup> p_gridLookup;
   // this vector makes sure we have shared ownership over the surfaces
   std::vector<std::shared_ptr<const Surface>> m_surfaces;
   // this vector is returned, so that (expensive) copying of the shared_ptr
   // vector does not happen by default
   SurfaceVector m_surfacesRawPointers;
   // this is only used to keep info on transform applied
   // by l2g and g2l
   Transform3 m_transform;
 };
 
 }  // namespace Acts

This page was automatically generated by the 2.3.7 LXR engine. The LXR team