Acts/Utilities/IGrid.hpp

0001 // This file is part of the ACTS project.
0002 //
0003 // Copyright (C) 2016 CERN for the benefit of the ACTS project
0004 //
0005 // This Source Code Form is subject to the terms of the Mozilla Public
0006 // License, v. 2.0. If a copy of the MPL was not distributed with this
0007 // file, You can obtain one at https://mozilla.org/MPL/2.0/.
0008
0009 #pragma once
0010
0011 #include "Acts/Utilities/IAxis.hpp"
0012
0013 #include <algorithm>
0014 #include <any>
0015 #include <typeinfo>
0016
0017 #include <boost/container/small_vector.hpp>
0018
0019 namespace Acts {
0020
0021 namespace detail {
0022
0023 template <typename>
0024 class AnyGridView;
0025 template <typename>
0026 class AnyGridConstView;
0027
0028 }  // namespace detail
0029
0030 /// Base class for all grid types
0031 class IGrid {
0032  public:
0033   virtual ~IGrid() = default;
0034
0035   /// Get a dynamically sized vector of axis objects for inspection
0036   /// @return a vector of axis pointers
0037   virtual boost::container::small_vector<const IAxis*, 3> axes() const = 0;
0038
0039   /// Get the number of dimensions of the grid
0040   /// @return The number of dimensions of the grid
0041   virtual std::size_t dimensions() const = 0;
0042
0043   /// Get the type of the values stored in the grid
0044   /// @return The type of the values stored in the grid
0045   virtual std::type_info const& valueType() const = 0;
0046
0047   /// Type-erased interface to access the contents of the grid
0048   ///
0049   /// @note This interface has non-negligible runtime overhead due to packing
0050   ///       and unpacking from/to @c std::any and the dynamically sized index and
0051   ///       point types. **USE WITH CARE!**
0052   ///
0053   /// @{
0054   using AnyIndexType = boost::container::small_vector<std::size_t, 3>;
0055   /// Type alias for dynamic point type (coordinates as vector of doubles)
0056   using AnyPointType = boost::container::small_vector<double, 3>;
0057
0058   /// Get the lower left edge of a bin for a given set of indices
0059   /// @param indices The indices to get the lower left edge of the bin for
0060   /// @return The lower left edge of the bin
0061   virtual AnyPointType lowerLeftBinEdgeAny(AnyIndexType indices) const = 0;
0062
0063   /// Get the upper right edge of a bin for a given set of indices
0064   /// @param indices The indices to get the upper right edge of the bin for
0065   /// @return The upper right edge of the bin
0066   virtual AnyPointType upperRightBinEdgeAny(AnyIndexType indices) const = 0;
0067
0068   /// Get the center of a bin for a given set of indices
0069   /// @param indices The indices to get the center of the bin for
0070   /// @return The center of the bin
0071   virtual AnyPointType binCenterAny(AnyIndexType indices) const = 0;
0072
0073   /// Get the number of local bins for a given set of indices
0074   /// @return The number of local bins
0075   virtual AnyIndexType numLocalBinsAny() const = 0;
0076
0077   /// @}
0078
0079   /// Helper to print out the grid
0080   /// @param os the output stream
0081   /// @param grid the grid to print
0082   /// @return the output stream
0083   friend std::ostream& operator<<(std::ostream& os, const IGrid& grid) {
0084     grid.toStream(os);
0085     return os;
0086   }
0087
0088   friend bool operator==(const IGrid& lhs, const IGrid& rhs) {
0089     auto lhsAxes = lhs.axes();
0090     auto rhsAxes = rhs.axes();
0091     return lhsAxes.size() == rhsAxes.size() &&
0092            std::equal(lhsAxes.begin(), lhsAxes.end(), rhsAxes.begin(),
0093                       [](const IAxis* a, const IAxis* b) { return *a == *b; });
0094   }
0095
0096  protected:
0097   /// @param os Output stream to write grid representation to
0098   virtual void toStream(std::ostream& os) const = 0;
0099
0100   /// Get the value of a bin for a given set of indices
0101   /// @param indices The indices to get the value of the bin for
0102   /// @return The value of the bin: the @c std::any contains a const pointer to
0103   ///         the value
0104   virtual std::any atLocalBinsAny(AnyIndexType indices) const = 0;
0105
0106   /// Get the value of a bin for a given set of indices
0107   /// @param indices The indices to get the value of the bin for
0108   /// @return The value of the bin: the @c std::any contains a pointer to the
0109   ///         value
0110   virtual std::any atLocalBinsAny(AnyIndexType indices) = 0;
0111
0112   template <typename>
0113   friend class AnyGridView;
0114   template <typename>
0115   friend class AnyGridConstView;
0116 };
0117
0118 }  // namespace Acts