Commit 1aa8f1f5 authored by Simon Spannagel's avatar Simon Spannagel
Browse files

DetectorField: move mapping coordinates into separate function

parent cd18ce9a

src/core/geometry/DetectorField.hpp

+12 −0
Original line number Diff line number Diff line
@@ -209,6 +209,18 @@ namespace allpix { 
         */

        T get_field_from_grid(const double x, const double y, const double z, const bool extrapolate_z) const noexcept;



        /**

         * @brief Map x and y coordinates of a position and a reference point onto a pixel given the chosen mapping.

         *

         * @param pos Position to calculate coordinates for

         * @param ref Reference position to calculate relative position to

         *

         * @return Tuple with relative x and y coordinates, mapped into the chosen area, and booleans indicating whether

         *         flipping of vector components is necessary

         */

        std::tuple<double, double, bool, bool> map_coordinates(const ROOT::Math::XYZPoint& pos,

                                                               const ROOT::Math::XYPoint& ref) const;



        /**

         * @brief Fast floor-to-int implementation without overflow protection as std::floor

         * @param x Double-precision floating point value

src/core/geometry/DetectorField.tpp

+54 −42
Original line number Diff line number Diff line
@@ -112,12 +112,37 @@ namespace allpix { 
            return {};

        }



        T ret_val;

        if(type_ == FieldType::GRID) {

            // Map the coordinates onto the chosen pixel fraction

            auto [px, py, flip_x, flip_y] = map_coordinates(pos, ref);



            // Intentionally do floating-point equality comparison to avoid us landing on the edge of the field

            px -= (px == 1.0 ? std::numeric_limits<double>::epsilon() : 0.);

            py -= (py == 1.0 ? std::numeric_limits<double>::epsilon() : 0.);



            ret_val = get_field_from_grid(px, py, z, extrapolate_z);



            // Flip vector if necessary

            flip_vector_components(ret_val, flip_x, flip_y);

        } else {

            // Calculate the coordinates relative to the reference point:

            auto x = pos.x() - ref.x() + offset_[0];

            auto y = pos.y() - ref.y() + offset_[1];



        T ret_val;

        if(type_ == FieldType::GRID) {

            // Calculate the field from the configured function:

            ret_val = function_(ROOT::Math::XYZPoint(x, y, z));

        }



        return ret_val;

    }



    template <typename T, size_t N>

    std::tuple<double, double, bool, bool> DetectorField<T, N>::map_coordinates(const ROOT::Math::XYZPoint& pos,

                                                                                const ROOT::Math::XYPoint& ref) const {

        // Calculate the coordinates relative to the reference point:

        auto x = pos.x() - ref.x() + offset_[0];

        auto y = pos.y() - ref.y() + offset_[1];



        // Do we need to flip the position vector components?

        auto flip_x =
@@ -157,20 +182,7 @@ namespace allpix { 
            py += (y >= 0 ? 0. : 1.0);

        }



            // Intentionally do floating-point equality comparison to avoid us landing on the edge of the field

            px -= (px == 1.0 ? std::numeric_limits<double>::epsilon() : 0.);

            py -= (py == 1.0 ? std::numeric_limits<double>::epsilon() : 0.);



            ret_val = get_field_from_grid(px, py, z, extrapolate_z);



            // Flip vector if necessary

            flip_vector_components(ret_val, flip_x, flip_y);

        } else {

            // Calculate the field from the configured function:

            ret_val = function_(ROOT::Math::XYZPoint(x, y, z));

        }



        return ret_val;

        return {px, py, flip_x, flip_y};

    }



    // Maps the field indices onto the range of -d/2 < x < d/2, where d is the scale of the field in coordinate x.