feat(geo): TrackingVolume gets portal storage

Core/include/Acts/Geometry/Portal.hpp

@@ -212,6 +212,10 @@ class Portal {
   /// @return The portal surface
   const RegularSurface& surface() const;
 
+  /// Access the portal surface that is shared between the two links
+  /// @return The portal surface
+  RegularSurface& surface();
+
  private:
   /// Helper to check surface equivalence without checking material status. This
   /// is needed because we allow fusing portals with surfaces that are

Core/include/Acts/Geometry/TrackingVolume.hpp

@@ -48,6 +48,7 @@ class IVolumeMaterial;
 class Surface;
 class TrackingVolume;
 struct GeometryIdentifierHook;
+class Portal;
 
 /// Interface types of the Gen1 geometry model
 /// @note This interface is being replaced, and is subject to removal
@@ -301,6 +302,26 @@ class TrackingVolume : public Volume {
   /// @return the range of volumes
   MutableVolumeRange volumes();
 
+  using MutablePortalRange =
+      detail::TransformRange<detail::Dereference,
+                             std::vector<std::shared_ptr<Portal>>>;
+
+  using PortalRange =
+      detail::TransformRange<detail::ConstDereference,
+                             const std::vector<std::shared_ptr<Portal>>>;
+
+  /// Return all portals registered under this tracking volume
+  /// @return the range of portals
+  PortalRange portals() const;
+
+  /// Return mutable view of the registered portals under this tracking volume
+  /// @return the range of portals
+  MutablePortalRange portals();
+
+  /// Add a portal to this tracking volume
+  /// @param portal The portal to add
+  void addPortal(std::shared_ptr<Portal> portal);
+
   /// Add a child volume to this tracking volume
   /// @param volume The volume to add
   /// @note The @p volume will have its mother volume assigned to @p this.
@@ -494,6 +515,7 @@ class TrackingVolume : public Volume {
   std::string m_name;
 
   std::vector<std::unique_ptr<TrackingVolume>> m_volumes;
+  std::vector<std::shared_ptr<Portal>> m_portals;
 };
 
 }  // namespace Acts

Core/src/Geometry/Portal.cpp

@@ -172,6 +172,11 @@ const RegularSurface& Portal::surface() const {
   return *m_surface;
 }
 
+RegularSurface& Portal::surface() {
+  assert(m_surface != nullptr);
+  return *m_surface;
+}
+
 Portal Portal::merge(const GeometryContext& gctx, Portal& aPortal,
                      Portal& bPortal, BinningValue direction,
                      const Logger& logger) {

Core/src/Geometry/TrackingVolume.cpp

@@ -11,6 +11,7 @@
 #include "Acts/Definitions/Direction.hpp"
 #include "Acts/Geometry/GeometryIdentifier.hpp"
 #include "Acts/Geometry/GlueVolumesDescriptor.hpp"
+#include "Acts/Geometry/Portal.hpp"
 #include "Acts/Geometry/VolumeBounds.hpp"
 #include "Acts/Material/IMaterialDecorator.hpp"
 #include "Acts/Material/IVolumeMaterial.hpp"
@@ -424,6 +425,18 @@ void TrackingVolume::closeGeometry(
                                         logger);
     }
   }
+
+  GeometryIdentifier::Value iportal = 0;
+  for (auto& portal : portals()) {
+    auto portalId = GeometryIdentifier(volumeID).setBoundary(++iportal);
+    assert(portal.isValid() && "Invalid portal encountered during closing");
+
+    portal.surface().assignGeometryId(portalId);
+  }
+
+  for (auto& volume : volumes()) {
+    volume.closeGeometry(materialDecorator, volumeMap, vol, hook, logger);
+  }
 }
 
 // Returns the boundary surfaces ordered in probability to hit them based on
@@ -641,4 +654,16 @@ TrackingVolume& TrackingVolume::addVolume(
   return *m_volumes.back();
 }
 
+TrackingVolume::PortalRange TrackingVolume::portals() const {
+  return PortalRange{m_portals};
+}
+
+TrackingVolume::MutablePortalRange TrackingVolume::portals() {
+  return MutablePortalRange{m_portals};
+}
+
+void TrackingVolume::addPortal(std::shared_ptr<Portal> portal) {
+  m_portals.push_back(std::move(portal));
+}
+
 }  // namespace Acts