feat: TGeo python binding

Examples/Python/CMakeLists.txt

@@ -97,6 +97,13 @@ else()
     target_sources(ActsPythonBindings PRIVATE src/GeoModelStub.cpp)
 endif()
 
+if(ACTS_BUILD_PLUGIN_TGEO)
+    target_link_libraries(ActsPythonBindings PUBLIC ActsPluginTGeo)
+    target_sources(ActsPythonBindings PRIVATE src/TGeo.cpp)
+else()
+    target_sources(ActsPythonBindings PRIVATE src/TGeoStub.cpp)
+endif()
+
 if(ACTS_BUILD_PLUGIN_TRACCC)
     target_link_libraries(ActsPythonBindings PUBLIC ActsPluginDetray)
     target_sources(ActsPythonBindings PRIVATE src/Detray.cpp)

Examples/Python/src/ModuleEntry.cpp

@@ -75,6 +75,7 @@ void addUtilities(Context& ctx);
 void addDigitization(Context& ctx);
 void addPythia8(Context& ctx);
 void addGeoModel(Context& ctx);
+void addTGeo(Context& ctx);
 void addJson(Context& ctx);
 void addDetray(Context& ctx);
 void addHepMC3(Context& ctx);
@@ -146,6 +147,7 @@ PYBIND11_MODULE(ActsPythonBindings, m) {
   addPythia8(ctx);
   addJson(ctx);
   addGeoModel(ctx);
+  addTGeo(ctx);
   addDetray(ctx);
   addHepMC3(ctx);
   addExaTrkXTrackFinding(ctx);

Examples/Python/src/TGeo.cpp

@@ -0,0 +1,87 @@
+// This file is part of the ACTS project.
+//
+// Copyright (C) 2016 CERN for the benefit of the ACTS project
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+#include "Acts/Plugins/Python/Utilities.hpp"
+#include "Acts/Plugins/TGeo/TGeoDetectorElement.hpp"
+#include "Acts/Plugins/TGeo/TGeoLayerBuilder.hpp"
+#include "Acts/Plugins/TGeo/TGeoParser.hpp"
+
+#include <vector>
+
+#include <TGeoManager.h>
+#include <TGeoVolume.h>
+#include <pybind11/pybind11.h>
+#include <pybind11/stl.h>
+#include <pybind11/stl/filesystem.h>
+
+namespace py = pybind11;
+using namespace pybind11::literals;
+
+namespace Acts::Python {
+void addTGeo(Context& ctx) {
+  auto [m, mex] = ctx.get("main", "examples");
+
+  auto tgeo = mex.def_submodule("tgeo");
+
+  {
+    py::class_<Acts::TGeoDetectorElement,
+               std::shared_ptr<Acts::TGeoDetectorElement>>(
+        tgeo, "TGeoDetectorElement")
+        .def("surface", [](const Acts::TGeoDetectorElement& self) {
+          return self.surface().getSharedPtr();
+        });
+  }
+
+  {
+    /// Helper function to test if the automatic geometry conversion works
+    ///
+    /// @param rootFileName is the name of the GDML file
+    /// @param sensitiveMatches is a list of strings to match sensitive volumes
+    /// @param localAxes is the TGeo->ACTS axis conversion convention
+    /// @param scaleConversion is a unit scalor conversion factor
+    tgeo.def("_convertToElements",
+             [](const std::string& rootFileName,
+                const std::vector<std::string>& sensitiveMatches,
+                const std::string& localAxes, double scaleConversion) {
+               // Return vector
+               std::vector<std::shared_ptr<const Acts::TGeoDetectorElement>>
+                   tgElements;
+               // TGeo import
+               TGeoManager::Import(rootFileName.c_str());
+               if (gGeoManager != nullptr) {
+                 auto tVolume = gGeoManager->GetTopVolume();
+                 if (tVolume != nullptr) {
+                   TGeoHMatrix gmatrix = TGeoIdentity(tVolume->GetName());
+
+                   TGeoParser::Options tgpOptions;
+                   tgpOptions.volumeNames = {tVolume->GetName()};
+                   tgpOptions.targetNames = sensitiveMatches;
+                   tgpOptions.unit = scaleConversion;
+                   TGeoParser::State tgpState;
+                   tgpState.volume = tVolume;
+                   tgpState.onBranch = true;
+
+                   TGeoParser::select(tgpState, tgpOptions, gmatrix);
+                   tgElements.reserve(tgpState.selectedNodes.size());
+
+                   for (const auto& snode : tgpState.selectedNodes) {
+                     auto identifier = Acts::TGeoDetectorElement::Identifier();
+                     auto tgElement = TGeoLayerBuilder::defaultElementFactory(
+                         identifier, *snode.node, *snode.transform, localAxes,
+                         scaleConversion, nullptr);
+                     tgElements.emplace_back(tgElement);
+                   }
+                 }
+               }
+               // Return the elements
+               return tgElements;
+             });
+  }
+}
+
+}  // namespace Acts::Python

Examples/Python/src/TGeoStub.cpp

@@ -0,0 +1,15 @@
+// This file is part of the ACTS project.
+//
+// Copyright (C) 2016 CERN for the benefit of the ACTS project
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+namespace Acts::Python {
+struct Context;
+}  // namespace Acts::Python
+
+namespace Acts::Python {
+void addTGeo(Context& /*ctx*/) {}
+}  // namespace Acts::Python