feat: visualization of grids (#552)

Added visualization of acceleration grids. Furthermore simplified parts of the illustrator class. Note that I have added a webpage generation tool with detray in mind to ACTSVG which can be used for debugging purposes to easily merge and switch between svgs

extern/actsvg/CMakeLists.txt

@@ -19,7 +19,7 @@ message( STATUS "Building actsvg as part of the Detray project" )
 # Declare where to get Actsvg from.
 set( DETRAY_ACTSVG_GIT_REPOSITORY "https://github.com/acts-project/actsvg.git"
    CACHE STRING "Git repository to take actsvg from" )
-set( DETRAY_ACTSVG_GIT_TAG "v0.4.35" CACHE STRING "Version of actsvg to build" )
+set( DETRAY_ACTSVG_GIT_TAG "v0.4.37" CACHE STRING "Version of actsvg to build" )
 mark_as_advanced( DETRAY_ACTSVG_GIT_REPOSITORY DETRAY_ACTSVG_GIT_TAG )
 FetchContent_Declare( actsvg
    GIT_REPOSITORY "${DETRAY_ACTSVG_GIT_REPOSITORY}"

plugins/svgtools/include/detray/plugins/svgtools/conversion/grid.hpp

@@ -0,0 +1,164 @@
+/** Detray library, part of the ACTS project (R&D line)
+ *
+ * (c) 2023 CERN for the benefit of the ACTS project
+ *
+ * Mozilla Public License Version 2.0
+ */
+
+#pragma once
+
+// Project include(s)
+#include "detray/core/detector.hpp"
+#include "detray/definitions/units.hpp"
+#include "detray/grids/axis.hpp"
+
+// Actsvg include(s)
+#include "actsvg/proto/grid.hpp"
+
+// System include(s)
+#include <algorithm>
+#include <optional>
+#include <string>
+#include <vector>
+
+namespace detray::svgtools::conversion {
+
+/// A functor to access the bin edges.
+template <typename scalar_t, detray::n_axis::label axis_label>
+struct edge_getter {
+    template <typename group_t, typename index_t, typename... Args>
+    DETRAY_HOST_DEVICE inline auto operator()(
+        [[maybe_unused]] const group_t& group,
+        [[maybe_unused]] const index_t index) const {
+        using accel_t = typename group_t::value_type;
+        if constexpr (detray::detail::is_grid_v<accel_t>) {
+            const auto grid = group[index];
+            const auto axis_bin_edges =
+                grid.axes().template get_axis<axis_label>().bin_edges();
+            std::vector<scalar_t> edges;
+            std::copy(axis_bin_edges.cbegin(), axis_bin_edges.cend(),
+                      std::back_inserter(edges));
+            return edges;
+        }
+        return std::vector<scalar_t>{};
+    }
+};
+
+/// @return the bin edges of the grid.
+template <typename detray::n_axis::label axis_label, typename detector_t,
+          typename link_t>
+auto bin_edges(const detector_t& detector, const link_t& link) {
+    using d_scalar_t = typename detector_t::scalar_type;
+    return detector.accelerator_store()
+        .template visit<edge_getter<d_scalar_t, axis_label>>(link);
+}
+
+// Calculating r under the assumption that the cylinder grid is closed in phi:
+// (bin_edge_min - bin_edge_max) / (2*pi).
+template <typename d_scalar_t>
+auto r_phi_split(const std::vector<d_scalar_t>& edges_rphi) {
+    const auto r = edges_rphi.back() * detray::constant<d_scalar_t>::inv_pi;
+    std::vector<d_scalar_t> edges_phi;
+    std::transform(edges_rphi.cbegin(), edges_rphi.cend(),
+                   std::back_inserter(edges_phi),
+                   [r](d_scalar_t e) { return e / r; });
+    return std::tuple(edges_phi, r);
+}
+
+/// @returns the actsvg grid type and edge values for a detray cylinder
+/// grid.
+template <typename detector_t, typename link_t, typename view_t>
+auto cylinder2_grid_type_and_edges(const detector_t& detector,
+                                   const link_t& link, const view_t&) {
+    assert(link.id() == detector_t::accel::id::e_cylinder2_grid);
+    auto edges_rphi = bin_edges<detray::n_axis::label::e_rphi>(detector, link);
+    auto edges_z = bin_edges<detray::n_axis::label::e_cyl_z>(detector, link);
+    auto [edges_phi, r] = r_phi_split(edges_rphi);
+    std::vector edges_r{r, r};
+
+    if (std::is_same_v<view_t, actsvg::views::x_y>) {
+        return std::tuple(actsvg::proto::grid::e_r_phi, edges_r, edges_phi);
+    }
+    if (std::is_same_v<view_t, actsvg::views::z_r>) {
+        return std::tuple(actsvg::proto::grid::e_x_y, edges_z, edges_r);
+    }
+    if (std::is_same_v<view_t, actsvg::views::z_phi>) {
+        return std::tuple(actsvg::proto::grid::e_x_y, edges_z, edges_phi);
+    }
+    if (std::is_same_v<view_t, typename actsvg::views::z_rphi>) {
+        return std::tuple(actsvg::proto::grid::e_x_y, edges_z, edges_rphi);
+    }
+    using scalar_t = typename detector_t::scalar_type;
+    return std::tuple(actsvg::proto::grid::e_x_y, std::vector<scalar_t>{},
+                      std::vector<scalar_t>{});
+}
+
+/// @returns the actsvg grid type and edge values for a detray disc grid.
+template <typename detector_t, typename link_t, typename view_t>
+auto disc_grid_type_and_edges(const detector_t& detector, const link_t& link,
+                              const view_t&) {
+    assert(link.id() == detector_t::accel::id::e_disc_grid);
+    auto edges_r = bin_edges<detray::n_axis::label::e_r>(detector, link);
+    auto edges_phi = bin_edges<detray::n_axis::label::e_phi>(detector, link);
+
+    if (std::is_same_v<view_t, typename actsvg::views::x_y>) {
+        return std::tuple(actsvg::proto::grid::e_r_phi, edges_r, edges_phi);
+    }
+    using scalar_t = typename detector_t::scalar_type;
+    return std::tuple(actsvg::proto::grid::e_x_y, std::vector<scalar_t>{},
+                      std::vector<scalar_t>{});
+}
+
+/// @returns the detray grids respective actsvg grid type and edge
+/// values.
+template <typename detector_t, typename link_t, typename view_t>
+auto get_type_and_axes(const detector_t& detector, const link_t& link,
+                       const view_t& view) {
+    using accel_ids_t = typename detector_t::accel::id;
+    switch (link.id()) {
+        case accel_ids_t::e_cylinder2_grid: {
+            return cylinder2_grid_type_and_edges(detector, link, view);
+        }
+        case accel_ids_t::e_disc_grid: {
+            return disc_grid_type_and_edges(detector, link, view);
+        }
+        default: {
+            using scalar_t = typename detector_t::scalar_type;
+            return std::tuple(actsvg::proto::grid::e_x_y,
+                              std::vector<scalar_t>{}, std::vector<scalar_t>{});
+        }
+    }
+}
+
+/// @brief Converts a detray grid to a actsvg proto grid.
+/// @param detector the detector
+/// @param index the index of the grid's volume
+/// @param view the view
+/// @returns a proto grid
+template <typename a_scalar_t, typename detector_t, typename view_t>
+std::optional<actsvg::proto::grid> grid(const detector_t& detector,
+                                        const std::size_t index,
+                                        const view_t& view) {
+    using d_scalar_t = typename detector_t::scalar_type;
+    using geo_object_ids = typename detector_t::geo_obj_ids;
+
+    const auto vol_desc = detector.volumes()[index];
+    const auto link = vol_desc.template link<geo_object_ids::e_sensitive>();
+    actsvg::proto::grid p_grid;
+
+    if (not link.is_invalid()) {
+        const auto [type, edges0, edges1] =
+            get_type_and_axes(detector, link, view);
+        p_grid._type = type;
+        std::transform(edges0.cbegin(), edges0.cend(),
+                       std::back_inserter(p_grid._edges_0),
+                       [](d_scalar_t v) { return static_cast<a_scalar_t>(v); });
+        std::transform(edges1.cbegin(), edges1.cend(),
+                       std::back_inserter(p_grid._edges_1),
+                       [](d_scalar_t v) { return static_cast<a_scalar_t>(v); });
+        return p_grid;
+    }
+    return {};
+}
+
+}  // namespace detray::svgtools::conversion

plugins/svgtools/include/detray/plugins/svgtools/conversion/information_section.hpp

@@ -24,6 +24,7 @@
 
 namespace detray::svgtools::conversion {
 
+/// @returns a point as a string.
 template <typename point3_t>
 inline std::string point_to_string(point3_t point) {
 
@@ -33,6 +34,7 @@ inline std::string point_to_string(point3_t point) {
     return stream.str();
 }
 
+/// @returns the information section for a detray surface.
 template <typename point3_t, typename detector_t>
 inline auto information_section(
     const typename detector_t::geometry_context& context,

plugins/svgtools/include/detray/plugins/svgtools/conversion/intersection_record.hpp

@@ -11,12 +11,26 @@
 #include "detray/intersection/intersection.hpp"
 #include "detray/plugins/svgtools/conversion/landmark.hpp"
 #include "detray/plugins/svgtools/meta/proto/intersection_record.hpp"
+#include "detray/plugins/svgtools/utils/intersection_utils.hpp"
 
 // System include(s)
 #include <vector>
 
 namespace detray::svgtools::conversion {
 
+/// @returns The proto intersection record from a list of points
+template <typename point3_t, typename container_t>
+inline auto intersection_record(const container_t& points) {
+    using p_intersection_record_t =
+        svgtools::meta::proto::intersection_record<point3_t>;
+    p_intersection_record_t p_ir;
+    for (const auto& point : points) {
+        const auto p_lm = svgtools::conversion::landmark<point3_t>(point);
+        p_ir._landmarks.push_back(p_lm);
+    }
+    return p_ir;
+}
+
 /// @returns The proto intersection record of a detray intersection record.
 template <typename point3_t, typename detector_t>
 inline auto intersection_record(
@@ -27,17 +41,13 @@ inline auto intersection_record(
                   detray::intersection2D<typename detector_t::surface_type,
                                          typename detector_t::transform3>>>&
         intersection_record) {
-    using p_intersection_record_t =
-        svgtools::meta::proto::intersection_record<point3_t>;
-    p_intersection_record_t p_ir;
-    std::vector<typename p_intersection_record_t::landmark_type> landmarks;
+    std::vector<typename detector_t::point3> points;
     for (const auto& record : intersection_record) {
-        const auto p_lm = svgtools::conversion::landmark<point3_t>(
+        const auto point = svgtools::utils::intersection_point(
             context, detector, record.second);
-        landmarks.push_back(p_lm);
+        points.push_back(point);
     }
-    p_ir._landmarks = landmarks;
-    return p_ir;
+    return svgtools::conversion::intersection_record<point3_t>(points);
 }
 
 }  // namespace detray::svgtools::conversion

plugins/svgtools/include/detray/plugins/svgtools/conversion/landmark.hpp

@@ -12,6 +12,7 @@
 #include "detray/intersection/intersection.hpp"
 #include "detray/plugins/svgtools/conversion/point.hpp"
 #include "detray/plugins/svgtools/meta/proto/landmark.hpp"
+#include "detray/plugins/svgtools/utils/intersection_utils.hpp"
 
 namespace detray::svgtools::conversion {
 
@@ -23,15 +24,17 @@ inline auto landmark(
     const detray::intersection2D<typename detector_t::surface_type,
                                  typename detector_t::transform3>&
         d_intersection) {
-    using p_landmark_t = svgtools::meta::proto::landmark<point3_t>;
-
-    const typename detector_t::vector3 dir{};
-    const detray::surface surface{detector, d_intersection.sf_desc};
-    const auto position = svgtools::conversion::point<point3_t>(
-        surface.local_to_global(context, d_intersection.local, dir));
+    const auto position =
+        svgtools::utils::intersection_point(context, detector, d_intersection);
+    return svgtools::conversion::landmark<point3>(position);
+}
 
+/// @returns The proto landmark of a detray point.
+template <typename point3_t, typename d_point3_t>
+inline auto landmark(d_point3_t& position) {
+    using p_landmark_t = svgtools::meta::proto::landmark<point3_t>;
     p_landmark_t p_lm;
-    p_lm._position = position;
+    p_lm._position = svgtools::conversion::point<point3_t>(position);
     return p_lm;
 }
 

plugins/svgtools/include/detray/plugins/svgtools/conversion/link.hpp

@@ -29,8 +29,8 @@ inline auto link(const typename detector_t::geometry_context& context,
 
     typename detector_t::vector3 dir{};
 
-    // Length of link arrow is currently hardcoded to 3.
-    constexpr double link_length = 3.;
+    // Length of link arrow is currently hardcoded.
+    constexpr double link_length = 4.;
 
     const auto [start, end] = svgtools::utils::link_points(
         context, detector, d_portal, dir, link_length);