fix!: Propagate the alignable volume to the Multilayer navigation policy

Core/include/Acts/Geometry/IndexGrid.hpp

@@ -20,6 +20,7 @@
 
 #include <algorithm>
 #include <array>
+#include <functional>
 #include <set>
 #include <string>
 #include <vector>
@@ -233,17 +234,38 @@ class IndexGrid {
   /// These are the cast parameters - copied from constructor
   std::array<AxisDirection, grid_type::DIM> casts{};
 
-  /// A transform to be applied to the position
-  Transform3 transform = Transform3::Identity();
+  /// Abrivation of the delegate to transform the
+  /// external point into the grid's coordinate system
+  using Delegate_t =
+      std::function<const Transform3&(const GeometryContext& gctx)>;
 
-  /// @brief  Constructor for a grid based surface attacher
+  /// Delegate to transform the external points into the grid's
+  /// coordinate system
+  Delegate_t toLocalFrame = nullptr;
+
+  /// Constructor for a grid based surface attacher
   /// @param igrid the grid that is moved into this attacher
   /// @param icasts is the cast values array
   /// @param itr a transform applied to the global position
   IndexGrid(grid_type&& igrid,
             const std::array<AxisDirection, grid_type::DIM>& icasts,
             const Transform3& itr = Transform3::Identity())
-      : grid(std::move(igrid)), casts(icasts), transform(itr) {}
+      : grid{std::move(igrid)},
+        casts{icasts},
+        toLocalFrame{
+            [itr](const GeometryContext& /*gctx*/) -> const Transform3& {
+              return itr;
+            }} {}
+  /// Constructor for a grid based surface attacher with alignable delegate
+  /// @param igrid the grid that is moved into this attacher
+  /// @param icasts is the cast values array
+  /// @param trfFunc a transform applied to the global position
+  IndexGrid(grid_type&& igrid,
+            const std::array<AxisDirection, grid_type::DIM>& icasts,
+            Delegate_t trfFunc)
+      : grid{std::move(igrid)},
+        casts{icasts},
+        toLocalFrame{std::move(trfFunc)} {}
 
   IndexGrid() = delete;
 };
@@ -299,7 +321,7 @@ struct IndexGridFiller {
         // Cast the transform according to the grid binning
         gridQueries.push_back(
             GridAccessHelpers::castPosition<decltype(iGrid.grid)>(
-                iGrid.transform * ref, iGrid.casts));
+                iGrid.toLocalFrame(gctx) * ref, iGrid.casts));
       }
       ACTS_DEBUG(gridQueries.size() << " reference points generated.");
       // These are now in the grid frame, can be expanded

Core/include/Acts/Navigation/IndexGridNavigationPolicy.hpp

@@ -105,7 +105,7 @@ class IndexGridNavigationPolicy : public INavigationPolicy {
     const auto& surfaces = m_volume.surfaces();
     const auto& indices =
         m_indexGrid.grid.atPosition(GridAccessHelpers::castPosition<GridType>(
-            m_indexGrid.transform * position, m_indexGrid.casts));
+            m_indexGrid.toLocalFrame(gctx) * position, m_indexGrid.casts));
     // Fill the navigation stream with the container
     for (const auto& idx : indices) {
       stream.addSurfaceCandidate(surfaces[idx], args.tolerance);

Core/src/Geometry/AlignablePortalVisitor.cpp

@@ -63,7 +63,7 @@ void AlignablePortalVisitor::visitVolume(TrackingVolume& volume) {
     assert(alignable.back() != nullptr);
   }
   ACTS_DEBUG("AlignablePortalVisitor() - Associate "
-             << alignable.size() << " porttals with the volume.");
+             << alignable.size() << " portals with the volume.");
   std::vector<Transform3> portalTrfBefore{};
   // If the visitor is in inspection mode, cache the transforms of the
   // unaligned portals
@@ -94,6 +94,18 @@ void AlignablePortalVisitor::visitVolume(TrackingVolume& volume) {
   }
   // Ensure that the portal remain where they were supposed to be
   for (std::size_t p = 0; p < alignable.size(); ++p) {
+    if (!alignable[p]->isAlignable()) {
+      ACTS_ERROR("AlignablePortalVisitor() - the "
+                 << p << "-the portal remains not alignable");
+      throw std::runtime_error(
+          "AlignablePortalVisitor() - The portal alignment failed");
+    }
+    if (alignable[p]->isSensitive()) {
+      ACTS_ERROR("AlignablePortalVisitor() - the "
+                 << p << "-the portal became sensitive");
+      throw std::runtime_error(
+          "AlignablePortalVisitor() - The portal alignment failed");
+    }
     if (!isSame(alignable[p]->localToGlobalTransform(m_gctx),
                 portalTrfBefore[p])) {
       ACTS_ERROR("AlignablePortalVisitor() - the "

Core/src/Geometry/MultiWireVolumeBuilder.cpp

@@ -97,10 +97,19 @@ MultiWireVolumeBuilder::createNavigationPolicyFactory() const {
                                                                         axisB);
 
   // The indexed grid to be filled from the navigation policy
-  IndexGrid<decltype(grid)> indexedGrid(
-      std::move(grid),
-      {protoAxisA.getAxisDirection(), protoAxisB.getAxisDirection()},
-      m_config.transform.inverse());
+  const auto* placement = m_config.alignablePlacement;
+  auto indexedGrid =
+      placement == nullptr
+          ? IndexGrid<decltype(grid)>{std::move(grid),
+                                      {protoAxisA.getAxisDirection(),
+                                       protoAxisB.getAxisDirection()},
+                                      m_config.transform.inverse()}
+          : IndexGrid<decltype(grid)>{
+                std::move(grid),
+                {protoAxisA.getAxisDirection(), protoAxisB.getAxisDirection()},
+                [placement](const GeometryContext& gctx) -> const Transform3& {
+                  return placement->localToGlobalTransform(gctx);
+                }};
 
   TryAllNavigationPolicy::Config tryAllConfig;
   tryAllConfig.portals = true;

Core/src/Navigation/MultiLayerNavigationPolicy.cpp

@@ -11,6 +11,16 @@
 #include "Acts/Geometry/ReferenceGenerators.hpp"
 #include "Acts/Surfaces/detail/IntersectionHelper2D.hpp"
 #include "Acts/Utilities/GridAccessHelpers.hpp"
+#include "Acts/Utilities/StringHelpers.hpp"
+namespace {
+std::string printCandidates(const std::vector<const Acts::Surface*>& surfaces) {
+  std::stringstream sstr{};
+  for (const auto* surf : surfaces) {
+    sstr << " --- " << surf->geometryId() << std::endl;
+  }
+  return sstr.str();
+}
+}  // namespace
 
 namespace Acts::Experimental {
 
@@ -40,7 +50,9 @@ void MultiLayerNavigationPolicy::initializeCandidates(
     NavigationPolicyState& /*state*/, AppendOnlyNavigationStream& stream,
     const Logger& logger) const {
   ACTS_VERBOSE("MultiLayerNavigationPolicy Candidates initialization for volume"
-               << m_volume.volumeName());
+               << m_volume.volumeName() << " @ "
+               << toString(m_volume.localToGlobalTransform(gctx)));
+
   const Transform3& itransform = m_volume.globalToLocalTransform(gctx);
   const Vector3 locPosition = itransform * args.position;
   const Vector3 locDirection = itransform.linear() * args.direction;
@@ -61,7 +73,8 @@ void MultiLayerNavigationPolicy::initializeCandidates(
   }
 
   ACTS_VERBOSE("MultiLayerNavigationPolicy Candidates reported "
-               << surfCandidates.size() << " candidates");
+               << surfCandidates.size() << " candidates. "
+               << "\n " << printCandidates(surfCandidates));
 
   // fill the navigation stream with the container
   for (const auto* surf : surfCandidates) {

Plugins/Json/src/IndexGridNavigationJsonConverter.cpp

@@ -50,7 +50,8 @@ void writeSurfacesAndProjections(
             std::array<Acts::AxisDirection, 2u> rphi = {
                 Acts::AxisDirection::AxisR, Acts::AxisDirection::AxisPhi};
             auto pVertex = Acts::GridAccessHelpers::castPosition<
-                Acts::RegularDiscIndexGrid>(indexGrid.transform * vertex, rphi);
+                Acts::RegularDiscIndexGrid>(
+                indexGrid.toLocalFrame(gctx) * vertex, rphi);
             // Update reference range
             referenceRange[0] = std::min(referenceRange[0], pVertex[0]);
             referenceRange[1] = std::max(referenceRange[1], pVertex[0]);
@@ -61,7 +62,7 @@ void writeSurfacesAndProjections(
             // Write the projected vertices
             jProjectedSurface.push_back(
                 Acts::GridAccessHelpers::castPosition<decltype(indexGrid.grid)>(
-                    indexGrid.transform * vertex, indexGrid.casts));
+                    indexGrid.toLocalFrame(gctx) * vertex, indexGrid.casts));
           }
         }
         jProjectedSurfaces.push_back(jProjectedSurface);