From 5ba961504ae1ab35c5e341d54e52b16db370efa1 Mon Sep 17 00:00:00 2001
From: Paul Gessinger <hello@paulgessinger.com>
Date: Tue, 27 Aug 2024 18:12:37 +0200
Subject: [PATCH] feat(geo): Add method to connect all outer links on portal

This works for single cylinders and for cylinder stacks
---
 Core/include/Acts/Geometry/PortalShell.hpp    |  4 ++
 Core/src/Geometry/PortalShell.cpp             | 10 ++++
 .../Core/Geometry/PortalShellTests.cpp        | 50 +++++++++++++++----
 3 files changed, 54 insertions(+), 10 deletions(-)

diff --git a/Core/include/Acts/Geometry/PortalShell.hpp b/Core/include/Acts/Geometry/PortalShell.hpp
index 3baaf43f69e..35b470d2d78 100644
--- a/Core/include/Acts/Geometry/PortalShell.hpp
+++ b/Core/include/Acts/Geometry/PortalShell.hpp
@@ -27,6 +27,8 @@ class PortalShellBase {
 
   virtual ~PortalShellBase() = default;
 
+  virtual void connectOuter(TrackingVolume& volume) = 0;
+
  private:
 };
 
@@ -51,6 +53,8 @@ class CylinderPortalShell : public PortalShellBase {
   virtual const std::shared_ptr<Portal>& portalPtr(Face face) = 0;
 
   virtual void setPortal(std::shared_ptr<Portal> portal, Face face) = 0;
+
+  void connectOuter(TrackingVolume& volume) override;
 };
 
 class SingleCylinderPortalShell : public CylinderPortalShell {
diff --git a/Core/src/Geometry/PortalShell.cpp b/Core/src/Geometry/PortalShell.cpp
index 0811c5770c4..ecb96cbdd68 100644
--- a/Core/src/Geometry/PortalShell.cpp
+++ b/Core/src/Geometry/PortalShell.cpp
@@ -19,6 +19,16 @@
 
 namespace Acts {
 
+void CylinderPortalShell::connectOuter(TrackingVolume& volume) {
+  for (Face face : {PositiveDisc, NegativeDisc, OuterCylinder, InnerCylinder,
+                    NegativePhiPlane, PositivePhiPlane}) {
+    auto* portalAtFace = portal(face);
+    if (portalAtFace != nullptr) {
+      portalAtFace->fill(volume);
+    }
+  }
+}
+
 SingleCylinderPortalShell::SingleCylinderPortalShell(TrackingVolume& volume) {
   if (volume.volumeBounds().type() != VolumeBounds::BoundsType::eCylinder) {
     throw std::invalid_argument("Invalid volume bounds type");
diff --git a/Tests/UnitTests/Core/Geometry/PortalShellTests.cpp b/Tests/UnitTests/Core/Geometry/PortalShellTests.cpp
index 8a49b41f854..a9bbac95459 100644
--- a/Tests/UnitTests/Core/Geometry/PortalShellTests.cpp
+++ b/Tests/UnitTests/Core/Geometry/PortalShellTests.cpp
@@ -26,6 +26,19 @@ using namespace Acts::UnitLiterals;
 namespace Acts::Test {
 GeometryContext gctx;
 
+std::size_t getVolumeIndex() {
+  static std::size_t i = 1;
+  return i++;
+}
+
+auto makeVolume(auto&&... pars) {
+  TrackingVolume vol(Transform3::Identity(),
+                     std::make_shared<CylinderVolumeBounds>(
+                         std::forward<decltype(pars)>(pars)...));
+  vol.setVolumeName("cyl" + std::to_string(getVolumeIndex()));
+  return std::move(vol);
+};
+
 BOOST_AUTO_TEST_SUITE(PortalShellTests)
 
 BOOST_AUTO_TEST_CASE(ConstructionFromVolume) {
@@ -35,15 +48,6 @@ BOOST_AUTO_TEST_CASE(ConstructionFromVolume) {
   // | rMin > 0  | 1      | 3   |
   // | rMin == 0 | 2      | 4   |
 
-  std::size_t i = 1;
-  auto makeVolume = [&](auto&&... pars) {
-    TrackingVolume vol(Transform3::Identity(),
-                       std::make_shared<CylinderVolumeBounds>(
-                           std::forward<decltype(pars)>(pars)...));
-    vol.setVolumeName("cyl" + std::to_string(i++));
-    return std::move(vol);
-  };
-
   auto cyl1 = makeVolume(30_mm, 40_mm, 100_mm);
   auto cyl2 = makeVolume(0_mm, 40_mm, 100_mm);
   auto cyl3 = makeVolume(30_mm, 40_mm, 100_mm, 45_degree);
@@ -530,7 +534,33 @@ BOOST_AUTO_TEST_CASE(RDirection) {
   }
 }
 
-// @TODO: Should CylinderStackPortalShell also do the fusing?
+BOOST_AUTO_TEST_CASE(ConnectOuter) {
+  auto cyl1 = makeVolume(30_mm, 40_mm, 100_mm);
+  auto cyl2 = makeVolume(0_mm, 50_mm, 110_mm);
+
+  SingleCylinderPortalShell shell{cyl1};
+
+  using enum CylinderPortalShell::Face;
+  BOOST_CHECK_EQUAL(
+      shell.portal(OuterCylinder)->getLink(Direction::AlongNormal), nullptr);
+  BOOST_CHECK_EQUAL(
+      shell.portal(InnerCylinder)->getLink(Direction::OppositeNormal), nullptr);
+  BOOST_CHECK_EQUAL(shell.portal(PositiveDisc)->getLink(Direction::AlongNormal),
+                    nullptr);
+  BOOST_CHECK_EQUAL(
+      shell.portal(NegativeDisc)->getLink(Direction::OppositeNormal), nullptr);
+
+  shell.connectOuter(cyl2);
+
+  BOOST_CHECK_NE(shell.portal(OuterCylinder)->getLink(Direction::AlongNormal),
+                 nullptr);
+  BOOST_CHECK_NE(
+      shell.portal(InnerCylinder)->getLink(Direction::OppositeNormal), nullptr);
+  BOOST_CHECK_NE(shell.portal(PositiveDisc)->getLink(Direction::AlongNormal),
+                 nullptr);
+  BOOST_CHECK_NE(shell.portal(NegativeDisc)->getLink(Direction::OppositeNormal),
+                 nullptr);
+}
 
 BOOST_AUTO_TEST_SUITE_END()  // CylinderStack
 BOOST_AUTO_TEST_SUITE_END()